Full Question & Answer Text (for Search Engines)
Question 1:
A 54-year-old man presents with low back pain and lower extremity weakness. Imaging shows a solitary lesion located in the conus medullaris with enhancement after administration of gadolinium. The most likely diagnosis is:
Options:
- Epidermoid cyst
- Lymphoma
- Meningioma
- Ependymoma
- Astrocytoma
Correct Answer: Ependymoma
Explanation:
Ependymomas are the most common intramedullary tumor in adults and are found with equal prevalence in middle-aged men and women. They are most prevalent in the caudal regions of the spinal cord around the conus medullaris and filum terminale. Epidermoid cysts and dural-based meningiomas are extramedullary tumors. Astrocytomas are most commonly found in the lower cervical region, and a patient presents with neck pain and upper extremity deficits.
Question 2:
Which of the following diagnostic modalities is used most often to evaluate suspected malignant astrocytomas of the spinal cord:
Options:
- History and physical examination is often sufficient to make the diagnosis.
- Imaging characteristics of malignant astrocytomas on magnetic resonance imaging (MRI) are specific enough to make the diagnosis.
- Malignant astrocytoma of the spinal cord is a clinical diagnosis and is only confirmed after post-mortem tissue evaluation.
- An open biopsy with tissue evaluation is the only way to make the diagnosis.
- C omputed tomography with a myelogram
Correct Answer: An open biopsy with tissue evaluation is the only way to make the diagnosis.
Explanation:
Clinically, early symptoms of intramedullary tumors are nonspecific. Almost all intramedullary tumors show contrast uptake. Even though there are specific MRI characteristics to each tumor, enough variability and overlap exists in their radiologic appearance that histological examination is still required for definitive diagnosis.
Question 3:
The most effective treatment for malignant intramedullary tumors of the spinal cord is:
Options:
- Surgical excision
- Radiation therapy
- Chemotherapy
- Surgical excision followed by a combination of chemotherapy and radiation therapy.
- Neither a single treatment modality nor a combination of treatment modalities has proven effective in significantly improving mortality.
Correct Answer: Neither a single treatment modality nor a combination of treatment modalities has proven effective in significantly improving mortality.
Explanation:
Despite treatment, a poor prognosis is given to patients with malignant intramedullary tumors. The median survival time for patients with cervical tumors is 3 to 6 months. Surgical excision, radiation, and chemotherapy are not found to significantly improve survival. Treatment is generally supportive.
Question 4:
Initially, the most appropriate method to evaluate a patient with suspected peripheral nerve injury involves:
Options:
- An imaging study, preferably magnetic resonance imaging (MRI), of the injured region
- Electromyography and nerve conduction velocity studies
- A doppler ultrasound to study blood flow to the injured area
- An MRI of the entire spine to evaluate possible spinal cord injury
- A detailed neurologic evaluation noting distal motor function
Correct Answer: A detailed neurologic evaluation noting distal motor function
Explanation:
After a traumatic injury to peripheral nerves, early clinical examination is imperative. The key is to test for motor function in the most distal aspect of the nerve and be able to localize the site of injury. Imaging studies are far less sensitive than clinical examinations. Electromyography and nerve conduction velocity studies are usually performed during the follow-up examination to assess for residual, or recovery of, function.
Question 5:
The type of peripheral nerve injury that requires acute repair is:
Options:
- A sharp transection
- A blunt transection
- A contusion injury
- A stretch injury
- No peripheral nerve injury should be acutely repaired.
Correct Answer: A sharp transection
Explanation:
The type of traumatic peripheral nerve injury dictates the timing of repair. If a nerve has been sharply transected, then repair should be performed within 72 hours. This can be accomplished during the repair of associated skin, vessels, muscles, and tendons. For a sharply transected but partially cut nerve, early repair is also recommended. Bluntly transected nerves require delayed repair. Contusion and stretch injuries may require delayed surgery.
Question 6:
The proper treatment plan for contusion and stretch peripheral nerve injuries involves:
Options:
- Immediate surgical exploration and repair
- Delayed surgical repair 2 weeks after injury
- Immediate surgical exploration followed by delayed repair weeks to months later
- Observation only
- Observation followed by delayed surgical exploration if no functional recovery is found
Correct Answer: Delayed surgical repair 2 weeks after injury
Explanation:
For contusion and stretch peripheral nerve injuries, delayed surgery is recommended. Patients are followed for several weeks to months and monitored for functional nerve recovery. If there is no evidence of regeneration, then surgical exploration is performed.
Question 7:
The most common type(s) of peripheral nerve injury is:
Options:
- A sharp laceration injury
- A blunt laceration injury
- Contusion and stretch injuries
- A proximal root avulsion
- Traumatic peripheral nerve injuries occur with approximately the same frequency.
Correct Answer: Contusion and stretch injuries
Explanation:
The most common types of traumatic nerve injuries are contusion and stretch injuries. A severe blow to soft tissues or even a fracture can cause a contusion. Gunshot wounds, for example, may produce contusion injuries. Stretch injuries usually result from extreme movements of the limbs, most commonly the shoulder joint with involvement of the brachial plexus.
Question 8:
Which of the following is the anatomic origin of the Brown-Sequardâ s syndrome:
Options:
- Ischemic damage to the periphery of the cord
- Shear injury to the central cord
- Contusion to the dorsal cord
- Traumatic hemisection of the cord
- Complete transection of the cord
Correct Answer: Traumatic hemisection of the cord
Explanation:
Brown-Sequardâ s syndrome often results from penetrating wounds that cause anatomical hemisection of the cord. Shear injury to the central cord usually results in the central cord syndrome. Contusions to the spinal cord lead to level-specific and long-tract findings depending on the location of contusion. Complete transsection leads to complete neurologic loss.
Question 9:
Which of the following is the most common cause of and the treatment for conus medullaris syndrome:
Options:
- Traumatic injury treated with steroids
- Ischemic injury treated by medical management
- C hronic metabolic treated by correcting the underlying cause
- C ompressive lesion treated by surgical decompression
- Idiopathic, no treatment is needed
Correct Answer: C ompressive lesion treated by surgical decompression
Explanation:
Conus medullaris syndrome is caused by upper and lower motor neuron injury because of a combined spinal cord and nerve root injury caused by thoracolumbar injuries (levels between T-11 and L-1). Causative agents are compressive in nature such as a compression fracture or herniated disk. Treatment is emergent surgical decompression. The prognosis is better for incomplete injuries.
Question 10:
Which of the following is the most important prognostic sensory modality during examination of a patient with a spinal cord injury:
Options:
- Pain and temperature sensation carried by the spinothalamic tracts
- Light touch and joint position carried by the dorsal column tracts
- Joint position carried by the spinocerebellar tract
- All modalities carry the same prognostic value
- Sensory examination has no prognostic value in evaluation of spinal cord injury patients
Correct Answer: Pain and temperature sensation carried by the spinothalamic tracts
Explanation:
The most important prognostic sensory modalities are those carried in the lateral spinothalamic tract rather than dorsal columns.
Question 11:
Which of the following is the time window from the time of injury during which treatment of nonpenetrating spinal cord injury with methylprednisolone is indicated:
Options:
- 2 hours
- 4 hours
- 8 hours
- 12 hours
- 24 hours
Correct Answer: 8 hours
Explanation:
Administration of methylprednisolone within 8 hours of injury provides benefit to patients with spinal cord injury. Treatment of patients arriving after 8 hours of treatment has been shown to worsen morbidity. Therefore, patients arriving at trauma centers within this time receive methylprednisolone treatment as part of the standard of care. The exception is the group of patients with penetrating spinal cord injuries where the risk of treatment outweighs the potential benefits.
Question 12:
Pain from a herniated lumbar disk is caused by:
Options:
- Rupture of the thecal sac
- Local instability due to a ruptured nucleus pulposus
- Ischemia and potential necrosis of the nerve root
- Associated spinal stenosis
- Herniated nucleus pulposus and the resulting local inflammation
Correct Answer: Herniated nucleus pulposus and the resulting local inflammation
Explanation:
The annulus is composed of alternating laminae that are primarily composed of type I and type II collagen. The annulus is thinnest posterolaterally and thickest anteriorly. As the disk is loaded, the nucleus transfers axial loads to the annulus in the form of hoop stresses. With degenerative or traumatic processes, fissures or tears may develop in the annulus and the nucleus can become herniated. A herniated nucleus pulposus is a foreign material to the surrounding structures. The combination of mechanical pressure on a nerve root and local inflammation can lead to neurologic signs and symptoms.
Question 13:
The term Schmorlâ s nodule refers to:
Options:
- A giant synovial cyst
- An enlarged paravertebral lymph node
- A pathologic dorsal root ganglion
- Superior or inferior displacement of an intervertebral disk
- Anterior displacement of an intervertebral disk
Correct Answer: Superior or inferior displacement of an intervertebral disk
Explanation:
Superior and inferior displacements into the vertebral body are known as Schmorlâ s nodules.
Question 14:
A far lateral herniated nucleus pulposus at the L4-L5 level would lead to signs and symptoms of which nerve root on the affected side:
Options:
- L3
- L4
- L5
- S1
- None of the above
Correct Answer: L4
Explanation:
A far lateral herniated nucleus pulposus, which is less common, can lead to compression of the nerve root that has already exited the supra-adjacent foramen. Therefore, a far lateral L4-L5 herniated nucleus pulposus leads to L4 nerve root compression.
Question 15:
A sequestered disk herniation refers to:
Options:
- Bulging of the nucleus through a weakened annulus
- Rupture of the nucleus through the annulus
- Rupture of the nucleus through the annulus and the posterior longitudinal ligament
- Rupture of the nucleus through the posterior longitudinal ligament
- Separation of a herniated fragment from the disk
Correct Answer: Separation of a herniated fragment from the disk
Explanation:
A sequestered herniation is a separation of a herniated fragment from the disk from which it came.
Question 16:
Common presentations of cauda equina syndrome include:
Options:
- Severe low back pain with nausea and vomiting
- Acute onset unilateral foot drop
- Progressive chronic low back pain radiating to the gluteal region
- Saddle anesthesia and bowel and/or bladder dysfunction
- Fever, photophobia, and nuchal rigidity
Correct Answer: Saddle anesthesia and bowel and/or bladder dysfunction
Explanation:
In patients with suspected central herniated nucleus pulposus, cauda equina syndrome must not be missed as it could cause irreversible neurological damage. C auda equina syndrome presents with saddle anesthesia and bowel or bladder changes.
Question 17:
Which of the following statements is true regarding the natural history of a herniated lumbar disk:
Options:
- The natural history of a herniated lumbar disk is usually consistent with approximately 90% spontaneous resolution without intervention by 3 monthsâ follow-up.
- Surgical intervention is often required for definitive and long-term treatment.
- Despite aggressive surgical correction, permanent neurological deficits are common.
- Surgical diskectomy is a contraindication in patients with neurologic deficit.
- The natural history of lumbar disk herniations has not been studied.
Correct Answer: The natural history of a herniated lumbar disk is usually consistent with approximately 90% spontaneous resolution without intervention by 3 monthsâ follow-up.
Explanation:
A period of rest is prescribed for 1 to 2 days with supports under the knees and neck to minimize root tension. Also, nonsteroidal anti-inflammatory drugs are used. Prolonged bed rest is no longer advocated because it can lead to deconditioning of compensatory musculature. Ambulation is begun as tolerated after the first few days of an acute event. More than one-half of patients who initially present with low back pain recover within 1 week and more than 90% of patients recover in 1 to 3 months. Physical therapy is started as tolerated.
Question 18:
Long-term follow-up studies of surgical versus conservative treatment of herniated lumbar disks indicate:
Options:
- Conservative management yields better long-term outcome.
- Surgical intervention has better long-term results.
- No statistically significant difference in outcome is noted despite the type of treatment used.
- No long-term data are available.
- None of the above
Correct Answer: No statistically significant difference in outcome is noted despite the type of treatment used.
Explanation:
The prognosis of herniated lumbar disks is generally good regardless of treatment. Patients operated on for proven disk herniations improved more rapidly than patients treated nonoperatively. However, within 4 to 5 years, the outcomes begin to approximate each other.
Question 19:
The predominant cause of low back pain in the general population, aside from the general sprain and strains of the paraspinal structures, is attributed to:
Options:
- Spondylolisthesis
- Herniated nucleus pulposus
- Spinal stenosis
- Degenerative disk disease
- Vascular insufficiency
Correct Answer: Degenerative disk disease
Explanation:
The consequences of normal aging of the spine include progressive disk dehydration, chemical alterations and subsequent mechanical incompetenceâ of the intervertebral disk, which may be manifested in low back pain, although an exact correlation between disk degeneration and low back pain has not been established. Nevertheless, many believe that the predominant cause of persistent low back pain is degeneration of the disk.
Question 20:
Initial work-up of an otherwise healthy individual with acute onset low back pain should include:
Options:
- A complete history, physical examination, and follow-up imaging studies only if indicated
- A complete history, physical examination, and plain radiographs
- A magnetic resonance imaging study of the lumbar spine
- A computed tomography of the lumbar spine
- No evaluation is needed on initial visit as most low back pain resolves spontaneously
Correct Answer: A complete history, physical examination, and follow-up imaging studies only if indicated
Explanation:
All patients presenting with back pain should have a thorough history taken and a complete physical exam including a detailed neurologic exam. In the recently published Agency for Health C are Policy and Research C linical Practice Guideline on Acute Low Back Pain Problems in Adults, it was concluded that a focused physical exam was sufficient to assess a patient with acute or recurrent low back pain of fewer than 4 weeks duration, unless findings suggested an underlying tumor, or an infectious, a traumatic or a major neurologic syndrome.
