Orthopedic Board Review MCQs: Spine & Trauma | Part 61

Question 1

Sacral fractures are most likely to be associated with neurologic deficits when they involve what portion of the sacrum?

Explanation

DISCUSSION: Denis divided the sacrum into three zones: zone 1 represents the lateral ala, zone 2 represents the foramina, and zone 3 represents the central canal. A fracture is classified according to its most medial extension. Those in zone 3 are typically bursting-type fractures or fracture-dislocations and are most prone to neurologic sequelae.
REFERENCES: Denis F, Davis S, Comfort T: Sacral fractures: An important problem.

A retrospective analysis of 236 cases. Clin Orthop Relat Res 1988;227:67-81.
Wood KB, Denis F: Fractures of the sacrum and coccyx, in Vacarro AR (ed): Fractures of the Cervical, Thoracic and Lumbar Spine. New York, NY, Marcel Dekker, 2003, pp 473-488.

Question 2

Which of the following is associated with the use of bisphosphonates in the setting of metastatic breast cancer to the spine?

Explanation

DISCUSSION: The indications of bisphosphonate therapy in breast cancer patients range from the correction of hypercalcemia to the prevention of cancer treatment-induced bone loss. Bisphosphonates reduce metastatic bone pain in at least 50% of patients and can reduce the frequency of skeletal-related events by 30% to 40%. Osteonecrosis of the jaw could occur in up to 2.5% of breast cancer patients during long-term bisphosphonate therapy.
REFERENCE: Body JJ: Breast cancer: Bisphosphonate therapy for metastatic bone disease. Clin Cancer Res 2006;12:6258s-6263s.

Question 3

A 67-year-old retired steelworker was involved in a motor vehicle accident and sustained a midcervical spinal cord injury. Radiographs and MRI scans reveal severe cervical stenosis and spondylosis without fractures or dislocations. Neurologic examination reveals an ASIA C spinal cord impairment with greater motor involvement of the upper extremities than the lower extremities. What is the probability that the patient eventually will become ambulatory?

Explanation

DISCUSSION: The patient sustained an incomplete spinal cord injury known as central cord syndrome. Central cord syndrome characteristically has disproportionate involvement of the upper extremities with the lower extremities being relatively spared. It is most commonly seen after cervical injuries in elderly patients with spondylosis and spinal stenosis, often without fracture. Penrod and associates noted that 23 of 59 patients with central cord syndrome

(ASIA C and D) ultimately walked. The poorest prognosis, however, was in ASIA C patients older than age 50, in which only 40% walked.
REFERENCES: Penrod LE, Hegde SK, Ditunno JF Jr: Age effect on prognosis for functional recovery in acute, traumatic central cord syndrome. Arch Phys Med Rehab 1990;71:963-968.
Northrup BE: Acute injuries to the spine and spinal cord: Evaluation and early treatment, in Clark CR (ed): The Cervical Spine, ed 4. Philadelphia, PA, Lippincott Williams & Wilkins, 2005, p 735.

Question 4

A 20-year-old man involved in a motor vehicle accident is brought to the emergency department with a C6-7 unilateral facet dislocation. His neurologic examination reveals a focal left-sided C7 nerve root palsy. He is awake and cooperative with questioning and has no other obvious traumatic injuries. What is the most appropriate treatment at this time?

Explanation

DISCUSSION: In the patient who is neurologically intact or has an incomplete injury from a cervical facet dislocation, a closed reduction with weighted tong traction is appropriate when the patient is awake, alert, and cooperative. Although there is a risk that a cervical facet dislocation could occur with an underlying cervical disk herniation, Vaccaro and associates have shown that closed reduction can be safely carried out in the awake, responsive patient. Closed reduction can be performed in the emergency department with traction with skull tongs or a halo ring. A slow stepwise application of weight is added until a reduction is achieved. Any worsening of the neurologic status of the patient requires immediate termination of the closed reduction and further diagnostic imaging before proceeding with further treatment.
REFERENCES: Vaccaro AR, Falatyn SP, Flanders AE, et al: Magnetic resonance evaluation of the intervertebral disc, spinal ligaments, and spinal cord before and after closed traction reduction of cervical spine dislocations. Spine 1999;24:1210-1217.
Hart RA: Cervical facet dislocation: When is magnetic resonance imaging indicated? Spine 2002;27:116-117.
Cotler JM, Herbison GJ, Nasuti JF, et al: Closed reduction of traumatic cervical spine dislocation using traction weights up to 140 pounds. Spine 1993;18:386-390.

Question 5

A 66-year-old man reports a 2-week history of worsening low back and leg pain. He reports that his pain is aggravated by lying down and relieved by standing and walking. He notes that he has been losing weight recently and that his pain has been awakening him during the night. His medical history is significant for hypertension, coronary artery disease, and prostate cancer. His physical examination is essentially unremarkable. Lumbar radiographs are within normal limits. What is the most appropriate management for this patient?

Explanation

DISCUSSION: In the initial assessment of acute low back pain in adults, no diagnostic testing is indicated during the first 4 weeks in the absence of “red flags” for a serious underlying condition. The purpose of the initial assessment of acute low back pain in adults is to rule out serious underlying conditions presenting as low back pain. The Agency for Healthcare Policy and Research, in its 1994 clinical practice guideline, identified four serious conditions that may present with low back pain, including fracture, tumor, infection, and cauda equina syndrome. This patient has five “red flags” for a spinal tumor as a possible etiology of his low back pain, including age of older than 50 years, constitutional symptoms (recent weight loss), pain worse when supine, severe nighttime pain, and a history of cancer. Of these, his history of cancer is most significant, as greater than 90% of spinal tumors are metastatic. In order of frequency, breast, prostate, lung, and kidney make up approximately 80% of all secondary spread to the spine. In the presence of “red flags” for tumor or infection, it is recommended that the clinician obtain a CBC count, ESR, and a urinalysis. If these are within normal limits and suspicions still remain, consider consultation or seek further evidence with a bone scan, radiographs, or additional laboratory studies. Negative radiographs alone are insufficient to rule out disease. If radiographs are positive, the anatomy can be better defined with MRI.
REFERENCES: Agency for Health Care Policy and Research, Bigos SJ (ed): Acute Low Back Problems in Adults. Rockville, MD, US Department of Health and Human Services, AHCPR Publication 95-0642, Clinical Practice Guideline #14, 1994.
Gertzbein SD: Metastatic spine tumors, in Herkowitz HN, Dvorak J, Bell G, et al (eds): The Lumbar Spine, ed 3. Philadelphia, PA, Lippincott Williams & Wilkins, 2004, pp 792-802.

Question 6

Which of the following increases radiation exposure to patients and personnel during surgery?

Explanation

DISCUSSION: Continuous fluoroscopy and cine radiography expose the patient and personnel to markedly increased levels of direct and scatter radiation exposure. Continuous fluoroscopy should be limited to only what is absolutely needed for safe completion of the procedure. By orienting the cathode ray tube beneath the patient and placing the image intensifier as close as clinically possible to the patient, scatter radiation exposure to the personnel is minimized.
REFERENCE: Wagner L, Archer B: Minimizing Risks from Fluoroscopic X-rays: A Credentialing Program for Anesthesiologists, Cardiologists, Surgeons, Radiologists, and Urologists, ed 3. The Woodlands, TX, Partners in Radiation Management, 2000.

Question 7

A 78-year-old woman undergoes her third lumbar decompression and fusion from L3 to L5 without complication. On the morning of postoperative day 3, examination reveals painless, flaccid weakness of both lower extremities. She also has an absent bulbocavernous reflex and a mild saddle paresthesia. MRI scans of the lumbar spine are shown in Figures 26a and 26b. What is the most appropriate management at this time?

Explanation

DISCUSSION: The MRI scans reveal a large postoperative hematoma causing significant thecal compression. An epidural hematoma with neurologic deficit is a surgical emergency requiring immediate evacuation of the hematoma. Although the incidence of postoperative epidural hematomas is rare, the consequences of a missed diagnosis can be catastrophic. Early recognition and evacuation are essential in preserving or restoring neurologic function. Uribe and associates attributed delayed postoperative hematomas to previous multiple lumbar surgeries as a possible contributing factor.
REFERENCES: Yi S, Yoon do H, Kim KN, et al: Postoperative spinal epidural hematoma: Risk factor and clinical outcome. Yonsei Med J 2006;47:326-332.
Uribe J, Moza K, Jimenez O, et al: Delayed postoperative spinal epidural hematomas. Spine J 2003;3:125-129.

Question 8

Figures 27a through 27c show the radiographs and CT scan of a 27-year-old man who sustained a low-velocity gunshot wound to the neck. He is quadriplegic (ASIA A), hemodynamically stable, and does not have drainage from his wound. After initial resuscitation and stabilization, the cervical spine and spinal cord injuries are best managed by

Explanation

DISCUSSION: Although the spinal canal has been penetrated, the lateral masses are intact bilaterally with only partial destruction of the vertebral body and penetration of the lamina on one side, thus the cervical spine is not unstable and surgical stabilization is not indicated. Dural repair is not indicated since there is no external cerebrospinal fluid leakage. Surgical treatment should be based on the need to treat extraspinal pathology only.
REFERENCES: Bono CM, Heary RF: Gunshot wounds to the spine. Spine J 2004;4:230-240.
Punjabi MM, Jue JJ, Dvorak J, et al: Cervical spine kinematics and clinical instability, in Clark CR (ed): The Cervical Spine, ed 4. Philadelphia, PA, Lippincott Williams & Wilkins, 2005,

pp 55-87.

Question 9

Which of the following is a true statement regarding thoracic disk herniations?

Explanation

DISCUSSION: Symptomatic herniations of the thoracic spine are much less common than those of the cervical or lumbar region. They tend to occur most commonly during the third to fifth decades of life and although they can be found at all levels, they are most common in the lower third near the thoracolumbar region. Posterior laminectomy and disk excision has the highest rate of neurologic deterioration and is not recommended. Multiple studies have shown that herniated thoracic disks can be found at one or more levels in 40% of asymptomatic individuals.
REFERENCES: Shah RP, Grauer JN: Thoracoscopic excision of thoracic herniated disc, in Vaccaro AR, Bono CM (eds): Minimally Invasive Spine Surgery. New York, NY, Informa Healthcare, 2007, pp 73-80.
Bohlman HH, Zdeblick TA: Anterior excision of herniated thoracic discs. J Bone Joint Surg Am 1988;70:1038-1047.

Question 10

A sentinel event is defined as an unexpected occurrence involving death or serious physical or psychological injury, or the risk thereof. What is the most common sentinel event related to spine surgery?

Explanation

DISCUSSION: Patient safety and prevention of medical errors is a major focus of recent national advocacy groups. Analysis has shown that the most common sentinel event in spine surgery is surgery on the wrong level. Therefore, it is recommended that every patient have the surgical site signed, the level of surgery marked intraoperatively, and a radiograph taken. Surgery on the wrong level is most likely to occur in single-level decompressive procedures.
REFERENCES: Wong DA, Watters WC III: To err is human: Quality and safety issues in spine care. Spine 2007;32:S2-S8.
Wong DA: Spinal surgery and patient safety: A systems approach. J Am Acad Orthop Surg 2006;14:226-232.

Question 11

What structure is most at risk with anterior penetration of C1 lateral mass screws?

Explanation

DISCUSSION: Posterior screw fixation of the upper cervical spine has gained a great deal of popularity due to its stable fixation, obviating the use of halo vest immobilization, and its high fusion rates. The use of screws in this location, however, has introduced a whole new set of potential complications. Vertebral artery injury is one of the most feared complications associated with screws in the C1/C2 region. This structure, however, is lateral and posterior at the C2 level and then penetrates the foramen transversarium of C1 to lie cephalad to the arch of C1 before entering the foramen magnum. It is the internal carotid artery that lies immediately anterior to the arch of C1 that is particularly at risk by anterior penetration of C1 lateral mass or C1-C2 transarticular screws as demonstrated by Currier and associates. The internal carotid artery lies posterior to the pharynx. The external carotid artery and the glossopharyngeal nerve are not at risk with this method of fixation.
REFERENCES: Currier BL, Todd LT, Maus TP, et al: Anatomic relationship of the internal carotid artery to the C1 vertebra: A case report of cervical reconstruction for chordoma and pilot study to assess the risk of screw fixation of the atlas. Spine 2003;28:E461-E467.
Grant JC: Grant’s Atlas of Anatomy, ed 6. Baltimore, MD, Williams & Wilkins, 1972.
Harms J, Melcher RP: Posterior C1-C2 fusion with polyaxial screw and rod fixation. Spine 2001;26:2467-2471.

Question 12

During the application of halo skeletal fixation, the most appropriate position for the placement of the anterior halo pins is approximately 1 cm above the superior orbital rim and

Explanation

DISCUSSION: Halo fixation is the most rigid form of cervical orthosis, but complications can arise from improper placement of the initial halo ring. A relatively safe zone for anterior pin placement is located 1 cm above the orbital rim and superior to the lateral two thirds of the orbit. This position avoids the supraorbital and supratrochlear nerves and arteries over the medial one third of the orbit. The more lateral positions in the temporal fossa have very thin bone and can interfere with the muscles of mastication. Posterior pin site locations are less critical; positioning on the posterolateral aspect of the skull, diagonal to the contralateral anterior pins, is generally desirable.
REFERENCES: Botte MJ, Byrne TP, Abrams RA, et al: Halo skeletal fixation: Techniques of application and prevention of complications. J Am Acad Orthop Surg 1996;4:44-53.
Garfin SR, Botte MJ, Nickel VL: Complications in the use of the halo fixation device. J Bone Joint Surg Am 1987;69:954.

Question 13

Figures 28a and 28b show the sagittal and axial lumbar MRI scans of a 72-year-old man who reports dull aching back pain that spreads to his legs, calves, and buttocks. He has had the pain for several years and it is precipitated by standing and walking and relieved by sitting. His symptoms have been worsening over the past year and he notes that he is leaning forward while walking to help relieve his symptoms. He has had no treatment to date. What is his prognosis if he chooses to pursue nonsurgical management for this condition?

Explanation

DISCUSSION: The patient has lumbar spinal stenosis and the MRI scans reveal the pathology at L4-5, which is secondary to posterior disk bulging and hypertrophy and infolding of the ligamentum flavum, as well as degenerative facet arthrosis. The degree of spinal stenosis is moderate and his symptoms are positional in nature. Tadokoro and associates reported on a prospective study of 89 patients older than 70 years of age who underwent nonsurgical management for lumbar spinal stenosis. They found the prognosis to be relatively good with patients scoring at “excellent” or “good” for activities of daily living at final follow-up. However, they did note that patients with a complete block on myelography did not respond favorably to nonsurgical management. Amundsen and associates reported on a 10-year prospective study comparing surgical care to nonsurgical management. They concluded that, while the long-term results largely favored surgical treatment, more than half of the nonsurgically managed patients had a satisfactory outcome. They also concluded that a delay of surgery for some months did not worsen the prognosis. Therefore, their recommendation was for an initial primarily nonsurgical approach.
REFERENCES: Amundsen T, Weber H, Nordal HJ, et al: Lumbar spinal stenosis: Conservative or surgical management? A prospective 10-year study. Spine 2000;25:1424-1435.
Hilibrand AS, Rand N: Degenerative lumbar stenosis: Diagnosis and management. J Am Acad Orthop Surg 1999;7:239-249.
Tadokoro K, Miyamoto H, Sumi M, et al: The prognosis of conservative treatments for lumbar spinal stenosis: Analysis of patients over 70 years of age. Spine 2005;30:2458-2463.

Question 14

Which of the following vertebrae has the smallest pedicle isthmic width in a nondeformity patient?

Explanation

DISCUSSION: The smallest pedicle isthmic width is at L1, whereas T12 has the largest pedicle width in the upper lumbar and lower thoracic spine. Although smaller in diameter than T12, both T10 and T11 have larger pedicle widths than L1.
REFERENCE: Ofiram E, Polly DW, Gilbert TJ Jr, et al: Is it safe to place pedicle screws in the lower thoracic spine than in the upper lumbar spine? Spine 2007;32:49-54.

Question 15

Which of the following represents a contraindication for interspinous process decompression for the treatment of lumbar spinal stenosis?

Explanation

DISCUSSION: Kondrashov and associates noted stable good outcomes at 4 years in 14 of 18 patients treated with X-STOP interspinous process decompression as defined as an improvement over preoperative Oswestry scores of 15 points or more. Similar results were seen after 1 year in a European study by Siddiqui and associates. Exclusion and inclusion criteria for these studies varied somewhat, but cauda equina syndrome was the only exclusion criteria listed in both studies. All of the other choices did not represent exclusion criteria in either study.
REFERENCES: Kondrashov DG, Hannibal M, Hsu KY, et al: Interspinous process decompression with the X-STOP device for lumbar spinal stenosis: A 4-year follow-up study.

J Spinal Disord Tech 2006;19:323-327.
Siddiqui M, Smith FW, Wardlaw D: One-year results of X Stop interspinous implant for the treatment of lumbar spinal stenosis. Spine 2007;32:1345-1348.

Question 16

Which of the following statements about hoarseness due to vocal cord paralysis after anterior cervical diskectomy and fusion is most accurate?

Explanation

DISCUSSION: It has been traditionally taught that a left-sided approach to the anterior cervical spine is associated with a lower incidence of injury compared to the right-sided approach. This is due in part to the anatomic differences in the path the recurrent laryngeal nerve (RLN) takes on the right as compared to the left. Both nerves ascend in the tracheoesophageal groove after branching off the vagus nerve in the upper thorax. The left-sided RLN loops around the aortic arch and stays relatively medial as compared to the right-sided RLN which loops around the right subclavian artery and is somewhat more lateral at this point, and therefore is theoretically more vulnerable as it ascends toward the larynx before becoming protected in the tracheoesophageal groove. Furthermore, the variant of a nonrecurrent inferior laryngeal nerve branching directly off the vagus nerve at the level of the midcervical spine is much more common on the right than the left. Despite this reasoning, there has been no clinical evidence to suggest that laterality of approach for anterior cervical surgery makes any difference in the incidence of vocal cord paralysis. Furthermore, two recent studies have shown that the incidence of RLN injury and vocal cord paralysis is equal with either side of approach.
REFERENCES: Beutler WJ, Sweeney CA, Connolly PJ: Recurrent laryngeal nerve injury with anterior cervical spine surgery risk with laterality of surgical approach. Spine 2001;26:1337-1342.
Kilburg C, Sullivan HG, Mathiason MA: Effect of approach side during anterior cervical discectomy and fusion on the incidence of recurrent laryngeal nerve injury. J Neurosurg Spine 2006;4:273-277.

Question 17

A 23-year-old man is involved in a motor vehicle accident. An AP radiograph is shown in Figure 29a, and axial and sagittal CT scans are shown in Figures 29b and 29c. Neurologic examination shows 1/5 strength of his quadriceps and iliopsoas on the right, with 1/5 quadriceps function on the left. Definitive treatment of his injury should consist of

Explanation

DISCUSSION: The imaging studies show a fracture-dislocation. Surgical treatment of this injury consists of a decompression reduction, stabilization, and fusion. A posterolateral decompression can also be performed as necessary. An isolated anterior procedure in this type of injury is contraindicated. The anterior longitudinal ligament is most likely intact; therefore, an anterior procedure further destabilizes the spine. Reduction by an anterior approach would also be difficult. Nonsurgical management of the neurologic injury in this patient is not indicated.
REFERENCES: Theiss SM: Thoracolumbar and lumbar spine trauma, in Stannard JP, Schmidt AH, Kregor PJ (eds): Surgical Treatment of Orthopaedic Trauma. New York, NY, Thieme, 2007, pp 179-207.
Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 201-216.

Question 18

Surgical treatment for symptomatic disk herniations is associated with which of the following?

Explanation

DISCUSSION: The recently published SPORT trial verifies that surgical treatment of symptomatic disk herniations is associated with early and sustained pain relief. The trial also verifies that nonsurgical management is associated with improved symptoms as well. Nerve root injury, recurrent herniation, and diskitis are known complications of surgery, but all are less common than described above.
REFERENCE: Weinstein JN, Lurie JD, Tosteson TD, et al: Surgical vs nonoperative treatment for lumbar disk herniation: The Spine Patient Outcomes Research Trial (SPORT) observational cohort. JAMA 2006;296:2451-2459.

Question 19

A 25-year-old man is unresponsive at the scene of a high-speed motor vehicle accident and remains obtunded. Initial evaluation in the emergency department reveals a left-sided femoral shaft fracture and a right-sided humeral shaft fracture. The cervical spine remains immobilized in a semi-rigid cervical collar, and the initial AP and lateral radiographs obtained in the emergency department are unremarkable. What is the most appropriate management at this time?

Explanation

DISCUSSION: Clearance of the cervical spine can be difficult in the obtunded or unresponsive patient. Various trauma series have been reported to detect up to 95% of cervical fractures but only when ideal imaging views have been obtained, which is not often possible in the unresponsive or uncooperative patient. Passively performed cervical flexion-extension under live fluoroscopy has been suggested but is not without inherent risk in the potentially unstable cervical spine. CT of the cervical spine has gained acceptance for the evaluation of these patients given the excellent evaluation of the osseous anatomy and for the common availability in most emergency departments. Sanchez and associates, using a protocol to evaluate for cervical spine injuries after blunt trauma, were able to detect 99% of cervical fractures with 100% specificity.
REFERENCES: Chiu WC, Haan JM, Cushing BM, et al: Ligamentous injuries of the cervical spine in unreliable blunt trauma patients: Incidence, evaluation, and outcome. J Trauma 2001;50:457-463.
Sanchez B, Waxman K, Jones T, et al: Cervical spine clearance in blunt trauma: Evaluation of a computed tomography-based protocol. J Trauma 2005;59:179-183.
Nunez D Jr: Value of complete cervical helical computed tomographic scanning in identifying cervical spine injury in the unevaluable blunt trauma patient with multiple injuries:

A prospective study. J Trauma 2000;48:988-989.

Question 20

A 55-year-old woman undergoes an anterior cervical diskectomy and fusion at C5-C6 through a left-sided approach. One year later, she requires an anterior cervical diskectomy and fusion on another level. Which of the following is considered a contraindication to performing a right-sided approach for the revision procedure?

Explanation

DISCUSSION: When attempting a revision anterior cervical approach from the side opposite the original approach, it is important to evaluate the function of the vocal cords. If this evaluation reveals dysfunction of the vocal cord on the side of the original approach, then an approach on the contralateral side should not be attempted. Injury to the stellate ganglion, which causes a Horner’s syndrome, should not preclude an approach on the contralateral side. While the side of the symptomatology can influence the surgeon’s choice as to the side of an anterior approach, it does not preclude a certain approach. When approaching the lower cervical spine from the right side, the recurrent laryngeal nerve can cross the surgical field and should be preserved. Excessive intraoperative pressure on the esophagus can increase the incidence of dysphagia, but its incidence is no different with either approach.
REFERENCES: Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 387-394.
Edwards CC II, Riew KD, Anderson PA, et al: Cervical myelopathy: Current diagnostic and treatment strategies. Spine J 2003;3:68-81.

Question 21

A 56-year-old woman sustained the fracture shown in Figures 30a and 30b in a motor vehicle accident. What mechanism is most likely responsible for the injury?

Explanation

DISCUSSION: The CT scans show a burst fracture that results from an axial load injury. The radiographic hallmark of a burst fracture is compression of the posterior cortex of the vertebral body with retropulsion of bone into the spinal canal. AP radiographs often show widening of the interpedicular distance with a fracture of the lamina.
REFERENCES: Theiss SM: Thoracolumbar and lumbar spine trauma, in Stannard JP, Schmidt AH, Kregor PJ (eds): Surgical Treatment of Orthopaedic Trauma. New York, NY, Thieme, 2007, pp 179-207.
Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 201-216.

Question 22

In providing culturally competent care to a Muslim woman with a cervical spine injury, which of the following most accurately describes the steps a male orthopaedist should take to respect her religious beliefs during his examination?

Explanation

DISCUSSION: In examining a traditional Muslim woman, a male physician should have another woman present, and the patient’s husband, if possible. Only the affected limb or area needing examination should be exposed.
REFERENCE: Jimenez R, Lewis VO (eds): Culturally Competent Care Guidebook. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2007.

Question 23

Figure 31 shows the radiograph of a 64-year-old woman who is seen in the emergency department following a motor vehicle accident. She has no voluntary motor function in her distal upper extremities or lower extremities. She does not have a bulbocavernosus reflex. She has a blood pressure of 80/50 mm Hg with a pulse of 50/min. Her hypotension does not improve with initial fluid resuscitation. Further treatment of her hypotension should consist of

Explanation

DISCUSSION: The hallmark of neurogenic shock is hypotension without tachycardia. It is associated most commonly with high cervical spinal cord injuries and results from loss of function of the sympathetic nervous system. Because the peripheral vasculature is dilated due to loss of its sympathetic tone, continued rapid administration of fluid corrects the hypotension and can quickly lead to fluid overload and congestive heart failure. Therefore, neurogenic shock is best treated by the use of pressors. Cardioversion or administration of antibiotics or systemic steroids is not appropriate treatment for this patient’s hypotension.
REFERENCES: Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 179-187.
Nockels RP: Nonoperative management of acute spinal cord injury. Spine 2001;26:S31-S37.

Question 24

What is the typical axial plane transverse angulation of the thoracic pedicles?

Explanation

DISCUSSION: Thoracic pedicles typically are angled 25 degrees medially at T₁ so the

starting point is more lateral. T₂ angles about 15 degrees, and then the pedicles average about

5 to 7 degrees down to T10. At T11 and 12, the angulation is minimal.
REFERENCES: Weinstein L: Pediatric Spine Principles and Practice. New York, NY, Raven Press, 1994, pp 1659-1681.
Lenke LG, Orchowski J: Segmental posterior spinal instrumentation: Thoracic spine to sacrum, in Frymoyer JW, Wiesel SW (eds): The Adult and Pediatric Spine, ed 3. Philadelphia, PA, Lippincott Williams and Wilkins, 2004, pp 537-552.

Question 25

What muscle is most often encountered during surgical approaches to C5-6?

Explanation

DISCUSSION: The omohyoid muscle crosses the surgical field from inferior lateral to anterior superior traveling from the scapula to the hyoid bone and may need to be transected. The posterior digastric crosses the field as well but higher near C3-4. The other muscles run longitudinally.
REFERENCES: Chang U, Lee MC, Kim DH: Anterior approach to the midcervical spine, in Kim DH, Henn JS, Vaccaro AR, et al (eds): Surgical Anatomy and Techniques to the Spine. Philadelphia, PA, Saunders Elsevier, 2006, pp 45-56.
Netter GH: Atlas of Human Anatomy. Summit, NJ, Ciba-Geigy Corporation, 1989.

Question 26

Which of the following lumbar disk components has the highest tensile modulus to resist torsional, axial, and tensile loads?

Explanation

DISCUSSION: The annulus fibrosis has a multilayer lamellar architecture mode of type I collagen fibers. Each successive layer is oriented at 30 degrees to the horizontal in the opposite direction, leading to a “criss-cross” type pattern. This composition allows the annulus, which has the highest tensile modulus, to resist torsional, axial, and tensile loads.
REFERENCE: Rhee JM, Schaufele M, Abdu WA: Radiculopathy and the herniated lumbar disc: Controversies regarding pathophysiology and management. J Bone Joint Surg Am 2006;88:2070-2080.

Question 27

When comparing the overall outcomes of surgical versus nonsurgical treatment of stable thoracolumbar burst fractures in patients without neurologic injury, 5 years following injury, the principle differences lie in

Explanation

DISCUSSION: When patients are compared at 5 years follow-up, there are no statistically significant differences between the two groups with respect to kyphosis, the degree of retropulsed bone resorption, pain and function levels, or the ability to return to work. Nonsurgical management of stable neurologically intact burst fractures has a very low incidence of complications.
REFERENCES: Wood K, Butterman G, Mehbod A, et al: Operative compared with nonoperative treatment of a thoracolumbar burst fracture without neurological deficit: A prospective, randomized study. J Bone Joint Surg Am 2003;85:773-781.
Shen WJ, Liu TJ, Shen YS: Nonoperative treatment versus posterior fixation for thoracolumbar junction burst fractures without neurologic deficit. Spine 2001;26:1038-1045.

Question 28

A 42-year-old woman who has had an 18-month history of severe low back pain is referred to your office for surgical evaluation. She reports that the pain initially began with right lower extremity pain and management consisted of oral analgesics, nonsteroidal anti-inflammatory drugs, and muscle relaxants. She has seen a chiropractor as well as a pain management specialist and she is status-post epidural steroid injections. She has also completed exhaustive physical therapy, as she is a certified athletic trainer and runs a health fitness program at a community hospital. Currently, she denies lower extremity pain and her pain is isolated to her low back and is subjectively graded as 8/10, with 10 being the worst pain she has ever experienced. The pain is interfering with her activities of daily living and she is seeking definitive treatment. Figures 32a through 32c show current MRI scans. Based on the current available medical literature, what is the most appropriate treatment?

Explanation

DISCUSSION: The MRI scans reveal advanced degenerative disk disease at L5-S1. Nonsurgical management has failed to provide relief and the patient is quite debilitated as a result of her back pain. Fritzell and associates demonstrated that in a well-informed and selected group of patients with severe low back pain, lumbar fusion can diminish pain and decrease disability more efficiently than commonly used nonsurgical treatments. In a recent updated Cochrane Review of surgery for degenerative lumbar spondylosis, it was noted that while Fritzell and associates appeared to provide strong evidence in favor of fusion, a more recent trial by Brox and associates demonstrated no difference between those patients undergoing lumbar fusion compared to those receiving cognitive intervention and exercise. The Cochrane Review suggests that this may reflect a difference between the control groups. Fritzell and associates compared lumbar fusion to standard 1990s “usual care,” whereas Brox and associates compared lumbar fusion to a “modern rehabilitation program.” Bear in mind that this patient is a certified athletic trainer and runs a hospital health fitness department; therefore, at least for purposes of this question, it can be assumed that she has participated in a “modern rehabilitation program.” The Cochrane Review goes on to state that preliminary results of three small trials of intradiskal electrotherapy suggest that it is ineffective and that preliminary data from three trials of disk arthroplasty do not permit firm conclusions.
REFERENCES: Gibson JN, Waddell G: Surgery for degenerative lumbar spondylosis: Updated Cochrane Review. Spine 2005;30:2312-2320.
Fritzell P, Hagg O, Wessberg P, et al: 2001 Volvo Award Winner in Clinical Studies: Lumbar fusion versus nonsurgical treatment for chronic low back pain: A multicenter randomized controlled trial from the Swedish Lumbar Spine Study Group. Spine 2001;26:2521-2532.
Brox JI, Sorensen R, Friis A, et al: Randomized clinical trial of lumbar instrumented fusion and cognitive intervention and exercises in patients with chronic low back pain and disc degeneration. Spine 2003;28:1913-1921.

Question 29

Figure 33 shows the MRI scan of a 55-year-old woman who has had a 6-week history of back and leg pain. Which of the following clinical scenarios is most consistent with the MRI scan findings at L4-L5?

Explanation

DISCUSSION: The MRI scan reveals a L4-L5 foraminal disk herniation originating from the L4-5 disk space that has migrated up into the foramen, compressing the left L4 nerve root. There is normal distribution of the roots in the cerebrospinal fluid, excluding arachnoiditis as a diagnosis, and disk herniation in this location would not result in cauda equina syndrome or myelopathy.
REFERENCE: McCullouch JA, Transfeldt EE: Macnab’s Backache, ed 3. Philadelphia, PA, Williams and Wilkins, 1997, pp 569-608.

Question 30

Intradiskal electrothermal therapy (IDET) uses an intradiskal catheter to deliver controlled thermal energy to the inner periphery of the annulus fibrosis of a chronically painful intervertebral disk. Lumbar diskography is used diagnostically to identify the presumed pain generator to be targeted with IDET. Based on the medical literature, what can be said about the current status of IDET?

Explanation

DISCUSSION: Intradiskal electrothermal therapy (IDET) initial clinical results were reported in 2000. The early case series were quite encouraging with reported therapeutic success rates of 60% to 80%. Early enthusiasm was high as IDET provided a nonsurgical treatment option for an otherwise complex and difficult clinical entity, chronic diskogenic low back pain. The actual mechanism of action was not well understood, and while the theoretic explanation made good sense, it did not hold up under laboratory testing. Soon clinical results from the field did not meet the high expectations set by the developers of the technique. Since those early case studies, a few level I evidence studies have been conducted, one by Freeman and associates and one by Pauza and associates. These randomized, placebo-controlled trials demonstrated no significant benefit of IDET over the placebo.
REFERENCES: Freeman BJ, Fraser RD, Cain CM, et al: A randomized, double-blind, controlled trial: Intradiscal electrothermal therapy versus placebo for the treatment of chronic discogenic low back pain. Spine 2005;30:2369-2377.
Pauza KJ, Howell S, Dreyfuss P, et al: A randomized, placebo-controlled trial of intradiscal electrothermal therapy for the treatment of discogenic low back pain. Spine J 2004;4:27-35.
Wetzel FT, McNally TA: Treatment of chronic discogenic low back pain with intradiskal electrothermal therapy. J Am Acad Orthop Surg 2003;11:6-11.

Question 31

A 56-year-old mechanic has had pain in the hypothenar region of his dominant right hand for the past 6 months. He reports weakness in his grip and pain is worse with activity. Which of the following examination findings is most suggestive of a cervical etiology?

Explanation

DISCUSSION: Hypothenar atrophy is a nonspecific sign that can be seen in ulnar neuropathy, C8 radiculopathy, or even cervical myelopathy; however, the atrophy usually is not unilateral and includes other muscle groups. The Spurling test is an excellent method of eliciting cervical radicular pain but involves hyperextension and ipsilateral rotation of the cervical spine, resulting in nerve root compression by reducing the cross-sectional area of the ipsilateral neuroforamen. Tinel’s sign at the levator scapulae, if present, is indicative of an upper cervical (C3 or C4) radiculopathy. A subluxable ulnar nerve at the cubital tunnel, while often asymptomatic, points toward cubital tunnel syndrome as an etiology for this patient’s pain. The shoulder abduction relief (SAR) sign (relief of upper extremity pain with shoulder abduction) is virtually pathognomic of cervical radiculopathy because this maneuver results in relaxation of a compressed and/or inflamed cervical nerve root. The SAR sign is the converse analog of the straight leg raising sign in the lumbar examination for lumbar radiculopathy, as it relieves tension in the nerve root, thereby relieving symptoms.
REFERENCES: Ducker TB, Zeidman SM: Neurologic and functional evaluation, in Clark CR (ed): The Cervical Spine, ed 3. Philadelphia, PA, Lippincott Raven, 1998, pp 143-161.
An HS: Clinical presentation of discogenic neck pain, radiculopathy, and myelopathy, in Clark CR (ed): The Cervical Spine, ed 3. Philadelphia, PA, Lippincott Raven, 1998, pp 755-764.
Hoppenfeld S: Physical examination of the cervical spine and temporomandibular joint, in Physical Examination of the Spine and Extremities. New York, NY, Appleton-Century-Crofts, 1976, pp 105-132.

Question 32

A 35-year-old woman reports an 8-week history of neck pain radiating to her right upper extremity. She denies any history of trauma or provocative event. Examination reveals decreased pinprick sensation in her right middle finger, otherwise sensation is intact bilaterally. Finger flexors and interossei demonstrate 5/5 motor strength bilaterally. Finger extensors are 4/5 on the right and 5/5 on the left. The triceps reflex is 1+ on the right and 2+ on the left. The most likely diagnosis is a herniated nucleus pulposus at what level?

Explanation

DISCUSSION: The patient’s neurologic examination is consistent with a C7 radiculopathy on the right side. In a patient with this symptom complex in the absence of trauma, a cervical disk herniation is the most common etiology for a C7 radiculopathy. There are eight cervical nerve roots and the C7 nerve exits at the C6-7 disk space and is most frequently impinged by a disk herniation at this level.
REFERENCES: Houten JK, Errico TJ: Cervical spondylotic myelopathy and radiculopathy: Natural history and clinical presentation, in Clark CR (ed): The Cervical Spine, ed 4. Philadelphia, PA, Lippincott Williams & Wilkins, 2005, pp 985-990.
Hoppenfeld S: Orthopaedic Neurology: A Diagnostic Guide to Neurologic Levels. Philadelphia, PA, JB Lippincott, 1977, pp 7-43.

Question 33

What is the most common nonanesthetic-related reversible cause of changes in intraoperative neurophysiologic monitoring data?

Explanation

DISCUSSION: Patient positioning that results in local nerve compression, plexus traction, or improper neck alignment is the most common nonanesthetic-related cause of changes in intraoperative neurophysiologic monitoring data during spinal surgery.
REFERENCES: Jones SC, Fernau R, Woeltjen BL: Use of somatosensory evoked potentials to detect peripheral ischemia and potential injury resulting from positioning of the surgical patient: Case reports and discussion. Spine J 2004;4:360-362.
Schwartz DM, Sestokas AK, Hilibrand AS, et al: Neurophysiological identification of position-induced neurologic injury during anterior cervical spine surgery. J Clin Monit Comput 2006;20:437-444.

Question 34

During a left-sided transforaminal lumbar interbody fusion at the L4-5 level, the surgeon notes a significant amount of bleeding that cannot be controlled while using a pituitary rongeur. What anatomic structure has been injured?

Explanation

DISCUSSION: The surgeon perforated the anterior longitudinal ligament and injured the common iliac artery. Bingol and associates described injuries to the vascular structures during lumbar disk surgery. The common iliac artery was most commonly affected and constituted 76.9% of injuries.
REFERENCE: Bingol H, Cingoz F, Yilmaz AT, et al: Vascular complications related to lumbar disc surgery: J Neurosurg 2004;100:249-253.

Question 35

Six weeks after onset, what is the most clearly accepted indication for surgical management for lumbar disk herniation?

Explanation

DISCUSSION: In the absence of a cauda equina syndrome or progressive weakness, the best indication for surgical management is refractory radicular pain. Surgical decision-making should not be based on the size of the herniation. Large extruded herniations tend to resolve more predictably than smaller herniations. Stable motor weakness and numbness resolve similarly in both surgical and nonsurgical management, although surgery hastens the process. When intractable radicular pain is the strict indication for surgery, surgical intervention provides substantial and more rapid pain relief than nonsurgical care.
REFERENCES: Rhee JM, Schaufele M, Abdu WA: Radiculopathy and the herniated lumbar disc: Controversies regarding pathophysiology and management. J Bone Joint Surg Am 2006;88:2070-2080.
Atlas SJ, Keller RB, Wu YA, et al: Long-term outcomes of surgical and nonsurgical management of sciatica secondary to a lumbar disc herniation: 10 year results from the Maine lumbar spine study. Spine 2005;30:927-935.

Question 36

A 45-year-old woman has idiopathic scoliosis. Surgery is to include an anterior thoracic release through an open left thoracotomy. The thoracotomy will have what effect on the patient’s pulmonary function postoperatively?

Explanation

DISCUSSION: A thoracotomy in an adult with idiopathic scoliosis causes a reduction in pulmonary function that often does not return to preoperative levels. What pulmonary function that does recover, recovers over many months. Long-term improvement in pulmonary function, compared to preoperative function, is rarely seen. This should be considered in planning surgical intervention in adults with scoliosis.
REFERENCES: Graham EJ, Lenke LG, Lowe TG, et al: Prospective pulmonary function evaluation following open thoracotomy for anterior spinal fusion in adolescent idiopathic scoliosis. Spine 2000;25:2319-2325.
Kishan S, Bastrom T, Betz RR, et al: Thoracoscopic scoliosis surgery affects pulmonary function less than thoracotomy at 2 years postsurgery. Spine 2007;32:453-458.

Question 37

Figure 1 shows the radiograph of a 60-year-old woman who underwent a previous operation for great toe pain 20 years ago. She has had increasing pain over the past 5 years and now reports pain with any motion, swelling, and clicking. She also reports pain under the ball of foot. What is the most appropriate management to alleviate her metatarsalgia and great toe pain?

Explanation

DISCUSSION: The patient has a failed Silastic implant. Nonsurgical management will not work at this point. A Keller resection will only exacerbate her metatarsalgia. Implant removal with structural bone grafting and MTP fusion is the most appropriate choice because restoration of length is needed to alleviate the forefoot pain and bone grafting is required to fuse the MTP joint because there is an abundance of osteolysis. Total toe implants do not offer good long-term outcomes and are very difficult to fit into the large exploded-out cavity of the proximal phalanx.
REFERENCES: Hecht PJ, Gibbons MJ, Wapner KL, et al: Arthrodesis of the first metatarsophalangeal joint to salvage failed silicone implant arthroplasty. Foot Ankle Int 1997;18:383-390.
Myerson MS, Schon LC, McGuigan FX, et al: Results of arthrodesis of the hallux metatarsophalangeal joint using bone graft for restoration of length. Foot Ankle Int

2000;21:297-306.

Question 38

A 47-year-old man with Charcot-Marie-Tooth (CMT) disease was treated with a fifth metatarsal head resection for a symptomatic bunionette 2 years ago. What is the most likely complication seen at this time?

Explanation

DISCUSSION: CMT is characterized by a cavovarus foot position that increases weight-bearing stresses along the lateral border. Removal of the fifth metatarsal head carries the risk of creating a transfer lesion at the fourth metatarsal head, particularly with a cavovarus foot. Claw toes are common in CMT, but the fifth toe would be flail in this situation. Ulceration is unlikely given the lack of underlying bone. Peroneal atrophy is associated with CMT but would not be a complication of this procedure. Charcot arthropathy is a neuropathic process frequently seen in individuals with diabetes mellitus.
REFERENCES: Kitaoka HB, Holiday AD Jr: Metatarsal head resection for bunionette: Long-term followup. Foot Ankle 1991;11:345-349.
Coughlin MJ, Mann RA, Saltzman CL: Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby, 2007, pp 1312-1315.

Question 39

A 19-year-old man was struck by a car and is seen in the emergency department with a grade IIIC open distal tibia and fibula fracture. Examination reveals that the toes are cool and dusky with a sluggish capillary refill. Angiography reveals a lesion in the posterior tibial artery amenable to repair. There is no sensation on the plantar aspect of the foot, and he is unable to flex his toes. A clinical photograph and radiograph are shown in Figures 2a and 2b. What is the next most appropriate step in management?

Explanation

DISCUSSION: In the past, loss of plantar sensation in this grade IIIC tibial fracture would have been an indication for below-knee amputation regardless of the potential for vascular repair. However the 2002 LEAP study divided 55 patients with loss of plantar sensation into two groups, the insensate amputation group and the insensate limb salvage group, with 55% of patients in the insensate salvage group regaining normal sensation 2 years after injury. Furthermore, those in the salvage group who remained insensate after 2 years had equivalent outcomes to those in the amputation group. Because of these findings, limb salvage with vascular repair and external stabilization with delayed closure is deemed appropriate treatment. Immediate intramedullary fixation is not indicated. Because ischemia, contusion, and stretch can adversely affect the tibial nerve, the additional insult of exploration of the nerve is also not advisable given the soft-tissue compromise.
REFERENCES: Bosse MJ, McCarthy ML, Jones AL, et al: The insensate foot following severe lower extremity trauma: An indication for amputation? J Bone Joint Surg Am 2005;87:2601-2608.
Lange RH, Bach AW, Hansen ST Jr, et al: Open tibial fractures with associated vascular injuries: Prognosis for limb salvage. J Trauma 1985;25:203-208.
Mackenzie EJ, Bosse MJ, Kellam JF, et al: Factors influencing the decision to amputate or reconstruct after high-energy lower extremity trauma. J Trauma 2002;52:641-649.
Baumgaertner MR, Tornetta P III (eds): Orthopaedic Knowledge Update: Trauma 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 65-74.

Question 40

The pathophysiology of a claw toe deformity includes muscular imbalance caused by which of the following relatively strong structures?

Explanation

DISCUSSION: The dynamic forces acting to maintain the position of the proximal phalanx at the head of the metatarsal are a balance between the extensor digitorum longus and the weaker intrinsic muscles. With hyperextension at the metatarsophalangeal joint, the intrinsic muscles become less efficient as plantar flexors. Consequently, the hyperextension deformity progresses in the metatarsophalangeal joint as the opposition of the intrinsic muscles to the extensor tendon lessens. This is in contrast to the situation in the interphalangeal joints, where the stronger flexors overpower the weaker intrinsic muscles, which act as the extensors. This combination of events leads to hyperextension at the metatarsophalangeal joint and flexion deformities at the interphalangeal joints, resulting in claw toe.
REFERENCES: Mizel MS, Yodlowski ML: Disorders of the lesser metatarsophalangeal Joints.

J Am Acad Orthop Surg 1995;3:166-173.
Coughlin MJ, Mann RA: Surgery of the Foot and Ankle, ed. 7. St Louis, MO, Mosby, 1999,

pp 325-328.

Question 41

A 26-year-old woman is seen in the emergency department with an intra-articular distal tibia fracture and a fibular fracture (pilon). The patient, her husband, and three small children have recently immigrated to the United States from Mexico. The husband and wife have both been in a migrant labor camp but have no immediate relatives in the States. What factor is most important when considering her recommended care and treatment?

Explanation

DISCUSSION: With documented use of a competent interpreter, informed consent should not be an issue. In Hispanic families, the husband often makes the ultimate decision regarding proceeding with surgery; however, he would not be expected to withhold recommended treatment. Hispanics may have a higher risk of comorbidities, but you do not expect this to be a significant concern with this patient. Claustrophobia and some fear of the unfamiliar may make additional imaging studies more difficult to arrange, but not impossible. The real concern is that with no extended family and three small children, the postoperative demand on the patient could significantly jeopardize her ability to comply with weight-bearing restrictions and overall ambulatory demands. Discharge planning and appropriate help may be paramount for a good outcome.
REFERENCES: Jimenez R, Lewis VO (eds): Culturally Competent Care Guidebook. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2007.

Question 42

A 57-year-old man with type II diabetes mellitus was successfully treated for a first occurrence forefoot full-thickness (Wagner II) diabetic foot ulcer underlying the third metatarsal head with associated hammertoe with a series of weight-bearing total contact casts. There was no evidence of osteomyelitis. The ulcer is now fully healed. He is insensate to the Semmes-Weinstein 5.07 (10 gm) monofilament. What is the next most appropriate step in management?

Explanation

DISCUSSION: This is the first occurrence of diabetic foot-specific morbidity. The patient has a foot deformity, a history of a diabetic foot ulcer, and is insensate to the monofilament. He is at moderate risk for the development of a recurrent ulcer. This is best avoided with therapeutic footwear. Commercially available depth-inlay shoes should be combined with a custom accommodative foot orthosis to accommodative the deformity.
REFERENCES: Pinzur MS, Slovenkai MP, Trepman E, et al: Guidelines for diabetic foot care: Recommendations endorsed by the Diabetes Committee of the American Orthopaedic Foot and Ankle Society. Foot Ankle Int 2005;26:113-119.
Pinzur MS, Dart HC: Pedorthic management of the diabetic foot. Foot Ankle Clin 2001;6:205-214.

Question 43

A 28-year-old man has had a 2-year history of progressive lateral ankle pain. History reveals that he underwent a triple arthrodesis at age 13 for a tarsal coalition. The pain has been refractory to braces, custom inserts, and nonsteroidal anti-inflammatory drugs. Weight-bearing radiographs of the ankle and foot are shown in Figures 3a through 3d. Surgical management should include which of the following?

Explanation

DISCUSSION: The patient has a valgus-supination triple arthrodesis malunion. Weight-bearing radiographs show excessive residual valgus through the subtalar joint, producing lateral subfibular impingement, and residual forefoot abduction and midfoot supination through the talonavicular joint, lateralizing the weight-bearing forces through the foot. The deformity is best managed with a medial displacement calcaneal osteotomy and transverse tarsal derotational osteotomy. Ankle arthroscopy and lateral ligament reconstruction are indicated in the event of ligament instability. Tendon transfer, lateral column lengthening, and heel cord lengthening are used for treatment of adult flatfoot from posterior tibial tendon insufficiency. Ankle arthrodesis and ankle arthroplasty are not indicated in this patient because the lateral ankle symptoms are the result of the underlying deformity in the hindfoot, the patient is young, and the ankle joint is relatively normal.
REFERENCES: Haddad SL, Myerson MS, Pell RF IV: Clinical and radiographic outcome of revision surgery for failed triple arthrodesis. Foot Ankle Int 1997;18:489-499.
Mäenpää H, Lehto MU, Belt EA: What went wrong in triple arthrodesis? An analysis of failures in 21 patients. Clin Orthop Relat Res 2001;391:218-223.

Question 44

If heel varus corrects with a Coleman block test, then the hindfoot deformity is flexible. This test proves that the varus is due to a

Explanation

DISCUSSION: The Coleman block test is used to evaluate the effect of the forefoot on the rearfoot varus. If the deformity corrects with the block, then the hindfoot deformity is flexible and the varus position is secondary to the plantar flexed first ray or valgus position of the forefoot. A rearfoot orthotic will not correct the forefoot cause of the deformity. The patient still may need a lateralizing calcaneal osteotomy to realign the hindfoot.
REFERENCES: Younger AS, Hansen ST Jr: Adult cavovarus foot. J Am Acad Orthop Surg 2005;13:302-315.
Alexander IJ, Johnson KA: Assessment and management of pes cavus in Charcot-Marie-Tooth disease. Clin Orthop Relat Res 1989;246:273-281.

Question 45

A 27-year-old man now reports dorsiflexion and inversion weakness after an automobile collision 6 months ago in which compartment syndrome developed isolated to the anterior and deep posterior compartments. Examination reveals the development of a progressive cavovarus deformity, but the ankle and hindfoot remain flexible. In addition to Achilles tendon lengthening, which of the following procedures is most likely to improve the motor balance of his foot and ankle?

Explanation

DISCUSSION: Compartment syndrome of the anterior and deep posterior compartments results in anterior tibialis and posterior tibialis tendon weakness, respectively. Furthermore, the long flexors to the hallux and lesser toes will be weak as well. The intact peroneus longus overpowers the weak anterior tibialis tendon, resulting in plantar flexion of the first metatarsal, cavus, and hindfoot varus. Therefore, transferring the peroneus longus to the dorsolateral midfoot reduces the first metatarsal plantar flexion torque, and possibly augments ankle dorsiflexion torque.
REFERENCES: Hansen ST: Functional Reconstruction of the Foot and Ankle. Philadelphia, PA, Lippincott, Williams & Wilkins, 2000, pp 433-435.
Vienne P, Schoniger R, Helmy N, et al: Hindfoot instability in cavovarus deformity: Static and dynamic balancing. Foot Ankle Int 2007;28:96-102.

Question 46

Figures 4a through 4c show the radiographs of a 43-year-old woman who sustained a twisting injury to her right ankle. She has ankle pain and tenderness medially and laterally. To help determine the optimal treatment, an external rotation stress radiograph of the ankle is obtained. This test is designed to evaluate the integrity of what structure?

Explanation

DISCUSSION: In the presence of a supination external rotation-type fracture of the distal fibula (Weber type B), stability of the ankle is best assessed by performing an external rotation stress AP view of the ankle. This test is used to assess the integrity of the deltoid ligament. The presence of a deltoid ligament rupture results in instability and generally is best managed surgically. The gravity stress test can also be used.
REFERENCES: Egol KA, Amirtharajah M, Tejwani NC, et al: Ankle stress test for predicting the need for surgical fixation of isolated fibular fractures. J Bone Joint Surg Am 2004;86:2393-2398.
McConnell T, Creevy W, Tornetta P III: Stress examination of supination external rotation-type fibular fractures. J Bone Joint Surg Am 2004;86:2171-2178.
Schock HJ, Pinzur M, Manion L, et al: The use of the gravity or manual-stress radiographs in the assessment of supination-external rotation fractures of the ankle. J Bone Joint Surg Br 2007;89:1055-1059.

Question 47

A 29-year-old patient sustains a closed, displaced joint depression intra-articular calcaneus fracture. In discussing potential complications of surgical intervention through an extensile lateral approach, which of the following is considered the most common complication following surgery?

Explanation

DISCUSSION: Delayed wound healing and wound dehiscence is the most common complication of surgical management of calcaneal fractures through an extensile lateral approach, occurring in up to 25% of patients. Most wounds ultimately heal with local treatment; the deep infection rate is approximately 1% to 4% in closed fractures. Posttraumatic arthritis may develop despite open reduction and internal fixation, but the percentages remain low. Peroneal tendinitis may occur from adhesions within the tendon sheath or from prominent hardware but is relatively uncommon. Nonunion of a calcaneal fracture is rare.
REFERENCES: Sanders RW, Clare MP: Fractures of the calcaneus, in Coughlin MJ, Mann RA, Saltzman CL (eds): Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby-Elsevier, 2007, vol 2, pp 2017-2073.
Sanders RW, Clare MP: Fractures of the calcaneus, in Bucholz RW, Heckman JD,

Court-Brown C (eds): Rockwood and Green’s Fractures in Adults, ed 6. Philadelphia, PA, Lippincott Williams & Wilkins, 2006, vol 2, pp 2293-2336.

Question 48

Figures 5a and 5b show the radiographs of a 56-year-old man who was seen in the emergency department following a twisting injury to his left ankle. Examination in your office 3 days later reveals marked swelling and diffuse tenderness to palpation about the ankle and leg. What is the next most appropriate step in management?

Explanation

DISCUSSION: The radiographs show an isolated posterior malleolus fracture which, given the injury mechanism, is highly suspicious for a Maisonneuve injury. As with any suspected extremity injury, radiographs including the joints above and below the level of injury are acutely indicated. Although MRI may reveal a ligamentous injury to the ankle and CT may show asymmetry of the ankle mortise or syndesmosis, both studies are considerably more costly and are not indicated in the absence of a complete radiographic work-up. Technetium bone scan is nonspecific and would be of limited value in this instance, as would repeat radiographs of the ankle.
REFERENCES: Walling AK, Sanders RW: Ankle fractures, in Coughlin MJ, Mann RA, Saltzman CL (eds): Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby-Elsevier, 2007, vol 2,

pp 1973-2016.
Marsh JL, Saltzman CL: Ankle fractures, in Bucholz RW, Heckman JD, Court-Brown C (eds): Rockwood and Green’s Fractures in Adults, ed 6. Philadelphia, PA, Lippincott Williams & Wilkins, 2006, vol 2, pp 2147-2247.

Question 49

A 61-year-old man has a symptomatic bunionette that is refractory to nonsurgical management. A radiograph is shown in Figure 6. What is the optimal surgical correction?

Explanation

DISCUSSION: The patient has a bunionette with a large 4-5 intermetatarsal angle. This requires not only ostectomy of the lateral prominence but metatarsal osteotomy to decrease the intermetatarsal angle. Excising the head results in a flail joint and creates the possibility of a transfer lesion. Condylectomy can reduce plantar pressures but does not address the bunionette. The joint surface is well maintained, thus there are no indications for resection.
REFERENCES: Coughlin MJ: Treatment of bunionette deformity with longitudinal diaphyseal osteotomy with distal soft tissue repair. Foot Ankle 1991;11:195-203.
Koti M, Maffulli N: Bunionette. J Bone Joint Surg Am 2001;83:1076-1082.

Question 50

A 25-year-old woman with a healed proximal tibiofibular fracture treated with an intramedullary nail 2 years ago is currently wearing an ankle-foot orthosis (AFO) and reports a persistent foot drop. She is unhappy with the AFO and has not seen any functional improvement despite months of physical therapy. Serial electromyograms (EMG) show no recent change over the past year. Examination and EMG findings are consistent with a tibialis anterior 1/5, extensor hallucis longus 2/5, extensor digitorum longus 2/5, posterior tibial tendon (PTT) 5/5, peroneals 3/5, flexor hallucis longus 5/5, and gastrocsoleus 5/5. No discrete nerve lesion was identified. The patient has a flexible equinovarus contracture. What is the most appropriate management?

Explanation

DISCUSSION: This pattern of injury is consistent with an unrecognized compartment syndrome of the anterior and lateral compartments. Transfer of the PTT through a long incision in the interosseous membrane corrects the foot drop deformity, and allows adequate dorsiflexion provided that the tendon to be transferred has a strength of 5/5. Muscles/tendons typically lose one grade of strength after transfer. Transfer into the tendons at the level of the ankle prevents overtensioning or pullout of a PTT tendon that is not long enough. Debridement of the scarred muscle in the anterior compartment decreases the risk of scarring down to the tendon transfer. Transfer of the peroneus longus is not preferred given its relative lack of strength and line of pull. Continued therapy and bracing are unlikely to lead to further improvement at 2 years after injury. An ankle fusion would correct the foot drop but would not address the tendon imbalances between the tibialis anterior and the peroneus longus, and the PTT and the peroneus brevis.
REFERENCES: Hansen ST Jr: Functional Reconstruction of the Foot and Ankle. Philadelphia, PA, Lippincott Williams & Wilkins, 2000, p 192.
Atesalp AS, Yildiz C, Komurcu M, et al: Posterior tibial tendon transfer and tendo-Achilles lengthening for equinovarus foot deformity due to severe crush injury. Foot Ankle Int 2002;23:1103-1106.
Scott AC, Scarborough N: The use of dynamic EMG in predicting the outcome of split posterior tibial tendon transfers in spastic hemiplegia. J Pediatr Orthop 2006;26:777-780.
Williams PF: Restoration of muscle balance of the foot by transfer of the tibialis posterior. J Bone Joint Surg Br 1976;58:217-219.

Question 51

In the Levine-Edwards classification of traumatic spondylolisthesis of the axis (Hangman's fracture), which fracture type is strictly contraindicated for the use of cervical traction?

Explanation

Type IIA fractures are characterized by severe angulation with minimal translation and are caused by flexion-distraction injuries. Application of cervical traction can exacerbate the injury by over-distracting the fracture site, risking iatrogenic spinal cord injury.

Question 52

A 28-year-old male sustains a closed, distal-third spiral fracture of the humerus. On initial exam, he has full wrist and finger extension. Following a closed reduction and splint application, he is unable to extend his wrist or fingers. What is the most appropriate next step in management?

Explanation

A secondary radial nerve palsy that develops immediately after a closed reduction of a humeral shaft fracture is an absolute indication for surgical exploration. This is due to the high risk of the nerve being entrapped within the fracture fragments during the reduction maneuver.

Question 53

A 65-year-old male with long-standing ankylosing spondylitis presents to the emergency department after a low-energy ground-level fall. He complains of severe lower neck pain but has no focal neurological deficits. Initial plain radiographs of the cervical spine are unremarkable. What is the most appropriate next step in management?

Explanation

Patients with ankylosing spondylitis are at high risk for highly unstable, transcortical or transdiscal spinal fractures even after minor trauma. Because these fractures are easily obscured by abnormal anatomy on plain radiographs, advanced imaging (CT or MRI) is mandatory.

Question 54

A 35-year-old female sustains a severe pelvic crush injury resulting in spinopelvic dissociation (U-type sacral fracture). On examination, she has profound weakness of the gastrocnemius-soleus complex and loss of perianal sensation. Which of the following nerve root levels is most likely directly compromised by the fracture pattern?

Explanation

Spinopelvic dissociation often involves Denis Zone III sacral fractures, which frequently injure the S1-S3 nerve roots. Compromise of these roots leads to plantarflexion weakness (S1, S2), loss of bowel/bladder control, and perianal numbness (S2-S4).

Question 55

A 24-year-old motorcyclist sustains a traumatic brachial plexus injury. Clinical examination reveals complete paralysis of the right upper extremity, an ipsilateral ptosis, and miosis. What does the presence of Horner's syndrome indicate regarding his nerve injury?

Explanation

Horner's syndrome (ptosis, miosis, anhidrosis) in the setting of a brachial plexus injury indicates disruption of the sympathetic chain. This is pathognomonic for a preganglionic avulsion of the lower roots (C8 and T1), which carries a poor prognosis for spontaneous recovery.

Question 56

An 82-year-old male presents with severe neck pain following a fall. CT demonstrates a Type II odontoid fracture with 4 mm of posterior displacement. He is neurologically intact and lives independently. What is the most significant advantage of posterior C1-C2 segmental instrumentation compared to halo-vest immobilization in this patient?

Explanation

In elderly patients with Type II odontoid fractures, halo-vest immobilization is associated with high respiratory morbidity and high mortality. Surgical stabilization (e.g., C1-C2 posterior fusion) significantly improves union rates and decreases long-term mortality despite higher initial surgical risks.

Question 57

A 25-year-old man sustains a C1 ring fracture after diving into a shallow pool. An open-mouth odontoid radiograph is obtained. According to the Rule of Spence, a sum of lateral mass displacement greater than 6.9 mm strongly implies an incompetent or ruptured injury to which of the following structures?

Explanation

A combined lateral mass overhang of more than 6.9 mm on an open-mouth view implies a rupture of the transverse ligament. This marks the fracture as an unstable injury pattern often requiring halo immobilization or surgical fusion.

Question 58

A 32-year-old woman sustains a closed, spiral fracture of the distal third of the humeral shaft (Holstein-Lewis fracture). Neurological examination prior to manipulation is fully intact. Immediately following closed reduction and splinting, she exhibits complete loss of wrist and finger extension and numbness in the first dorsal web space. What is the most appropriate next step in management?

Explanation

A radial nerve palsy that appears immediately after a closed reduction of a humeral shaft fracture requires immediate surgical exploration. The nerve is at high risk of being entrapped within the fracture site.

Question 59

A 55-year-old intravenous drug user presents with fever, severe thoracic back pain, and progressive paraparesis over 48 hours. MRI reveals extensive discitis/osteomyelitis at T7-T8 with a large ventral epidural abscess causing severe spinal cord compression and localized kyphosis. What is the most likely causative organism and the optimal initial surgical approach?

Explanation

S. aureus is the most common cause of spinal epidural abscesses. When accompanied by ventral cord compression and kyphosis from osteomyelitis/discitis, an anterior approach (corpectomy and fusion) is preferred to adequately decompress the cord and provide structural support.

Question 60

A 19-year-old restrained passenger in a high-speed motor vehicle collision sustains a flexion-distraction injury (Chance fracture) of the L2 vertebra. Based on the mechanism of injury, this patient is at highest risk for which of the following associated conditions?

Explanation

Chance fractures typically occur via a seatbelt mechanism, causing severe flexion and distraction. They are highly associated with intra-abdominal injuries, particularly hollow viscus injuries (bowel rupture) in up to 40-50% of cases.

Question 61

A 28-year-old man falls from a motorcycle, sustaining a traction injury to his right upper extremity. Clinical examination reveals profound weakness of the right upper limb, accompanied by right-sided ptosis, miosis, and anhidrosis. The presence of these specific facial findings most strongly indicates an avulsion injury to which nerve root?

Explanation

Ptosis, miosis, and anhidrosis describe Horner syndrome, which is caused by disruption of the cervical sympathetic chain. In the context of a brachial plexus injury, this reliably indicates an avulsion of the T1 nerve root.

Question 62

A 14-year-old boy presents with progressive thoracic back pain and a visible rounding of his upper back. Standing lateral radiographs are obtained to evaluate for Scheuermann kyphosis. According to the classic Sorensen criteria, radiographic confirmation of this diagnosis requires anterior wedging of at least what magnitude, involving how many consecutive vertebrae?

Explanation

The Sorensen criteria for diagnosing Scheuermann kyphosis define the condition radiographically by the presence of anterior wedging of 5 degrees or more in at least 3 consecutive thoracic vertebrae.

Question 63

A 6-year-old boy falls from monkey bars and sustains an extension-type supracondylar humerus fracture. Radiographs show a Gartland Type III pattern with posteromedial displacement of the distal fragment. Which peripheral nerve is at the greatest risk of injury in this specific displacement pattern?

Explanation

Posteromedial displacement of the distal fragment causes the proximal metaphyseal fragment to spike anterolaterally, placing the radial nerve at the highest risk of injury. Posterolateral displacement endangers the median nerve (or AIN).

Question 64

A 45-year-old man with a history of recurrent low back pain presents to the emergency department with acute worsening of his symptoms, radiating down both legs. Which of the following clinical findings is the most sensitive early clinical indicator of cauda equina syndrome?

Explanation

Urinary retention is the most sensitive symptom (approaching 90%) for true cauda equina syndrome. Postvoid residual volumes > 100-200 mL can help confirm this diagnosis prior to definitive MRI.

Question 65

A 38-year-old construction worker sustains a pelvic crush injury resulting in a sacral fracture. CT scan characterizes the fracture as Denis Zone III. This specific zone of injury is most strongly associated with which of the following complications?

Explanation

Denis Zone III sacral fractures involve the central sacral canal. Because they disrupt the sacral nerve roots bilaterally within the canal, they have the highest incidence of severe neurologic compromise, including bowel and bladder dysfunction (cauda equina injury).

Question 66

A 40-year-old avid cyclist presents with hand weakness. Examination shows isolated profound weakness of the adductor pollicis and dorsal interossei muscles of the right hand. Sensation in the small finger is completely normal, and the hypothenar muscles demonstrate normal bulk and strength. An ulnar nerve compression is most likely localized to which zone of Guyon's canal?

Explanation

Zone 2 of Guyon's canal contains the deep motor branch of the ulnar nerve. Compression here (especially distal to the hypothenar motor branches) produces isolated motor weakness of the interossei and adductor pollicis without sensory loss.

Question 67

An 82-year-old man with a long-standing history of ankylosing spondylitis presents to the emergency department complaining of severe neck pain after tripping on a rug. Initial plain AP and lateral radiographs of the cervical spine demonstrate extensive syndesmophytes but no obvious fracture. Neurological exam is intact. What is the most appropriate next step in management?

Explanation

Patients with ankylosing spondylitis have rigidly fused, brittle spines highly susceptible to occult fractures even from low-energy trauma. A CT scan of the cervical spine is mandatory in these patients complaining of neck pain, as plain radiographs are notoriously difficult to interpret and often miss fractures.

Question 68

A 75-year-old man presents with neck pain after a minor fall and is diagnosed with a Type II odontoid fracture. Non-operative management with a cervical orthosis is being considered. Which of the following represents the strongest independent risk factor for nonunion in this scenario?

Explanation

The two most significant risk factors for nonunion in Type II odontoid fractures treated non-operatively are initial fracture displacement > 5 mm and patient age > 50 years.

Question 69

A 22-year-old collegiate pitcher is diagnosed with true neurogenic thoracic outlet syndrome (TOS). In this condition, the compression typically involves a cervical rib or fibrous band compressing which specific component of the brachial plexus?

Explanation

True neurogenic thoracic outlet syndrome is rare and usually involves compression of the lower trunk of the brachial plexus (C8 and T1 roots) by a cervical rib or tight fibrous band, leading to intrinsic hand weakness and sensory symptoms.

Question 70

During a routine physical examination of a 60-year-old man with progressive gait unsteadiness and hand clumsiness, the examiner aggressively flicks the distal phalanx of the middle finger, causing reflex flexion of the thumb and index finger. This positive Hoffmann sign is indicative of compression or injury to which of the following?

Explanation

A positive Hoffmann sign represents an upper motor neuron lesion (hyperreflexia), classically seen in cervical myelopathy. It indicates compression or dysfunction of the descending corticospinal tract.

Question 71

A 30-year-old man sustains a completely displaced, vertically oriented femoral neck fracture (Pauwels Type III) following a high-energy fall. Surgical fixation is planned to preserve the native hip joint. Biomechanically, which of the following constructs provides the highest resistance to shear forces for this specific fracture pattern?

Explanation

Pauwels Type III fractures have high vertical shear angles. A sliding hip screw coupled with a derotation screw has been shown biomechanically to provide superior stability against vertical shear forces compared to multiple parallel cancellous screws.

Question 72

A 68-year-old woman presents with bilateral lower extremity pain and cramping that worsens with walking. You are attempting to differentiate between neurogenic and vascular claudication. Which of the following historical features is highly characteristic of neurogenic claudication?

Explanation

Neurogenic claudication (due to lumbar spinal stenosis) is classically relieved by lumbar flexion (e.g., sitting, leaning forward on a shopping cart), which increases the cross-sectional area of the spinal canal. Relief with simply standing still or worsened symptoms walking uphill are typical of vascular claudication.

Question 73

During an anterior shoulder stabilization procedure, the surgeon is carefully identifying the structures in the axilla to avoid injury to the axillary nerve. The axillary nerve exits the axilla posteriorly through the quadrilateral space. Which vascular structure directly accompanies the nerve through this space?

Explanation

The axillary nerve passes through the quadrilateral space accompanied by the posterior circumflex humeral artery. The boundaries of the space are the teres minor (superior), teres major (inferior), long head of triceps (medial), and the surgical neck of the humerus (lateral).

Question 74

A 70-year-old man presents with profound back stiffness. Radiographs show confluent, flowing ossification along the anterolateral aspect of the thoracic and lumbar spine. To radiographically differentiate diffuse idiopathic skeletal hyperostosis (DISH) from ankylosing spondylitis, the clinician should look for which of the following characteristic features of DISH?

Explanation

DISH is characterized by flowing anterolateral ossification across at least four contiguous vertebrae with relative preservation of the intervertebral disc heights. Unlike ankylosing spondylitis, DISH lacks severe sacroiliac joint erosions and marginal syndesmophytes.

Question 75

A 25-year-old man sustains a severely comminuted, closed tibial shaft fracture. Two hours later, he complains of severe leg pain out of proportion to the injury. An intracompartmental pressure monitor is placed. What absolute tissue pressure threshold is classically cited as an indication for immediate four-compartment fasciotomy?

Explanation

An absolute compartment pressure greater than 30 mm Hg is classically considered the threshold for performing a fasciotomy to prevent ischemic muscle necrosis. Alternatively, a delta pressure (diastolic blood pressure minus compartment pressure) of less than 30 mm Hg is also widely used.

Question 76

Which of the following is considered the most significant risk factor for nonunion of an Anderson-D'Alonzo Type II odontoid fracture treated with halo vest immobilization?

Explanation

The most significant risk factors for nonunion of a Type II odontoid fracture include initial displacement greater than 5 mm, angulation greater than 10 degrees, and advanced age (typically >50 years). Displacement >5 mm can lead to nonunion rates as high as 80% with nonoperative management.

Question 77

A 35-year-old man sustains a closed spiral fracture of the distal third of the humeral shaft. Upon initial evaluation, he is unable to extend his wrist or fingers. Following a successful closed reduction and splinting, his radial nerve palsy persists but has not worsened. What is the most appropriate next step in management?

Explanation

Primary radial nerve palsies associated with closed humeral shaft fractures are typically a neuropraxia and should be treated with observation and supportive splinting. Surgical exploration is indicated for open fractures, penetrating trauma, or if a secondary palsy develops after a closed reduction.

Question 78

A 45-year-old woman presents with severe right-sided neck pain radiating down her arm. Physical examination reveals weakness in wrist flexion and finger extension, a diminished triceps reflex, and decreased sensation over the dorsal aspect of the middle finger. Which cervical nerve root is most likely compressed?

Explanation

A C7 radiculopathy is characterized by weakness in the triceps (elbow extension), wrist flexors, and finger extensors. It presents with a diminished triceps reflex and sensory deficits over the middle finger.

Question 79

A 28-year-old man sustains a posterior fracture-dislocation of the hip. Following closed reduction, he is found to have weakness in ankle dorsiflexion and great toe extension, but intact plantar flexion. Sensation is decreased over the dorsum of the foot. Which specific neural structure is most likely injured?

Explanation

The peroneal division of the sciatic nerve is most commonly injured in posterior hip dislocations. It is more susceptible to stretch injury than the tibial division because its fascicles are larger, have less protective connective tissue, and are securely tethered at the fibular head.

Question 80

A 55-year-old diabetic patient presents with severe back pain, fevers, progressive bilateral lower extremity weakness, and urinary retention. MRI reveals a large ventral fluid collection with peripheral enhancement in the lumbar epidural space. What is the most likely causative organism and the optimal immediate management?

Explanation

Staphylococcus aureus is the most common causative organism of spinal epidural abscesses. The presence of progressive neurologic deficits, including cauda equina syndrome, mandates emergent surgical decompression.

Question 81

A 22-year-old motorcyclist sustains a severe traction injury to his right upper extremity, resulting in a flail, insensate arm. He is also noted to have right-sided ptosis, miosis, and anhidrosis. This specific facial presentation indicates an injury at which of the following anatomic levels, and what is its prognostic significance?

Explanation

Horner syndrome (ptosis, miosis, anhidrosis) indicates a preganglionic avulsion of the T1 nerve root due to disruption of the proximal sympathetic ganglion. Preganglionic avulsion injuries have an extremely poor prognosis for spontaneous recovery and are not amenable to primary nerve grafting.

Question 82

In the evaluation of a patient with a neurologically intact L1 burst fracture, which of the following MRI findings most strongly dictates the need for surgical stabilization over nonoperative management?

Explanation

Disruption of the posterior ligamentous complex (PLC) renders the spine mechanically unstable and is the strongest indication for surgical stabilization. Under the Thoracolumbar Injury Classification and Severity (TLICS) score, PLC disruption alone scores 3 points, tipping a burst fracture into a surgical recommendation.

Question 83

A 32-year-old man is admitted with a comminuted fracture of the tibial diaphysis. Twelve hours post-injury, his diastolic blood pressure is 85 mmHg and he complains of severe, unremitting leg pain. Intracompartmental pressure monitoring of the anterior compartment reveals a pressure of 60 mmHg. What is the most appropriate next step in management?

Explanation

The patient has a Delta P (Diastolic BP - Compartment Pressure) of 25 mmHg (85 - 60). A Delta P of 30 mmHg or less is an absolute indication for an immediate four-compartment fasciotomy to prevent irreversible muscle and nerve necrosis.

Question 84

A 72-year-old man with a known history of diffuse idiopathic skeletal hyperostosis (DISH) presents after a minor mechanical fall with moderate mid-back pain. His neurologic examination is normal, and initial plain radiographs of the thoracic spine are interpreted as negative. What is the most appropriate next step?

Explanation

Patients with ankylosing spinal conditions like DISH are highly susceptible to unstable extension-type fractures from even minor trauma. Because plain radiographs frequently miss these fractures, a CT scan of the entire spine is mandatory.

Question 85

A 48-year-old carpenter presents with progressive numbness in his small and ring fingers, accompanied by intrinsic hand muscle weakness. Clinical evaluation suggests ulnar nerve entrapment at the elbow. Which of the following structures is the most common site of compression for this condition?

Explanation

Osborne's ligament (the cubital tunnel retinaculum), which spans from the medial epicondyle to the olecranon, is the most common anatomic site of ulnar nerve compression at the elbow. The Arcade of Struthers is a more proximal, less common site of ulnar nerve entrapment.

Orthopedic Surgery Board Review MCQs: Arthroplasty, Trauma & Spine Part 255

Orthopedic Board Review MCQs: Spine, Trauma & Nerve | Part 61

Key Takeaway

Orthopedic Board Review MCQs: Spine, Trauma & Nerve | Part 61

Chapter Index