Full Question & Answer Text (for Search Engines)
Question 1:
Which of the following aspects of reconstruction of chronic posttraumatic dislocation of the radial head has not been shown to improve the success rate:
Options:
- Apex-posterior angulation
- Rigid fixation
- Slight lengthening
- Early range of motion
- Radiocapitellar pin fixation
Correct Answer: Radiocapitellar pin fixation
Explanation:
Reconstruction with an ulnar osteotomy with apex-posterior angulation and slight lengthening with rigid fixation to allow early range of motion have been shown to improve results. Radiocapitellar pin fixation may cause arthrosis, breakage, and infection so it is not routinely recommended.
Question 2:
In patients with idiopathic adolescent scoliosis, clinically noticeable shortness of breath from restrictive lung disease begins to occur at a mean curve of:
Options:
- 45° thoracic
- 45° lumbar
- 55° thoracic
- 75° thoracic
- 95° thoracic
Correct Answer: 75° thoracic
Explanation:
Clinically noticeable pulmonary compromise begins to occur at a mean curve of 75° thoracic, although a decrease can be measured by pulmonary function testing with curves as little as 50°. C or pulmonale does not occur until a curve is larger then 100°.
Question 3:
Which of the following statements is true of patients with idiopathic scoliosis not treated surgically (long-term follow-up data) when compared to nonscoliotic controls:
Options:
- Patients had an increased mortality rate.
- Patients had an increased rate of neuropathy.
- Patients had an increased prevalence of back pain.
- Patientsâ curves did not worsen after adulthood.
- Patients had an increased rate of spinal fractures.
Correct Answer: Patients had an increased mortality rate.
Explanation:
Patients with idiopathic scoliosis have a mortality rate that is not statistically different from the general population. They do not have a significant risk of neuropathy or spine fracture. Their curves worsen in maturity if they are greater than approximately 40°. They also have an increased prevalence of back pain.
Question 4:
The cause of Ehlers-Danlos syndrome types I (gravis) and II (mitis) is a mutation in which of the following:
Options:
- Fibrillin
- Fibroblast growth factor
- C ollagen type I
- C ollagen type II
- C ollagen type V
Correct Answer: C ollagen type I
Explanation:
Ehlers-Danlos syndrome is subclassified into at least nine types. Types I and II result from defects in type V collagen.
Question 5:
The most common neural injury after a supracondylar fracture of the distal humerus is:
Options:
- Anterior interosseous nerve
- Median nerve
- Posterior interosseous nerve
- Radial nerve
- Ulnar nerve
Correct Answer: Anterior interosseous nerve
Explanation:
The most commonly injured nerve after a supracondylar fracture of the distal humerus is the anterior interosseous nerve. An injury to this nerve results in the inability to flex the interphalangeal joint of the thumb and the distal interphalangeal joint of the index finger.
Question 6:
Which of the following conditions does not have a risk of cervical deformity greater than the general population:
Options:
- Neurofibromatosis
- Larsen syndrome
- Diastrophic dysplasia
- Achondroplasia
- Down syndrome
Correct Answer: Achondroplasia
Explanation:
Achondroplasia is associated with frequent stenosis of the foramen magnum in infancy, as well as lower cervical stenosis. However, it is not associated with an actual deformity of the cervical spine. By contrast, neurofibromatosis, Larsen syndrome, and diastrophic dysplasia are associated with infantile cervical kyphosis. Down syndrome is associated with the risk of upper cervical instability.
Question 7:
Which of the following iliac osteotomies provides the greatest freedom of mobilization of the acetabular segment:
Options:
- Salter osteotomy
- Pemberton osteotomy
- Steel osteotomy
- Chiari osteotomy
- Ganz osteotomy
Correct Answer: Ganz osteotomy
Explanation:
Osteotomies that are made closest to the acetabulum provide the greatest freedom of mobilization. Of the choices provided, the Ganz or Bernese osteotomy is made closest to the acetabulum.
Question 8:
Displaced tibial eminence fractures contain the attachment of which of the following structures in addition to the anterior cruciate ligament:
Options:
- The lateral meniscus
- The medial meniscus
- The posterior cruciate ligament
- The patellar ligament
- The fat pad
Correct Answer: The lateral meniscus
Explanation:
Displaced tibial eminence fractures have been shown by arthroscopy to routinely contain the anterior attachment of the lateral meniscus. In addition, the anterior tibial attachment of the meniscus is torn. The cruciate and the meniscus pull the fragment in different directions.
Question 9:
A 10-year-old boy sustains a type III avulsion of the anterior tibial eminence. When his knee is placed in extension, the fragment does not reduce. Which of the following factors is likely preventing its reduction:
Options:
- Interposed anterior horn of medial meniscus
- Interposed stump of anterior cruciate ligament
- Interposed cartilage flap of tibial plateau
- Increased intra-articular pressure from hematoma
- Opposing pull of cruciate and lateral meniscus
Correct Answer: Opposing pull of cruciate and lateral meniscus
Explanation:
Type III tibial eminence fractures usually contain attachments of both the anterior cruciate ligament and the lateral meniscus. The opposing pull of both of these structures often prevents reduction during extension of the knee.
Question 10:
A 13-year-old boy who underwent in situ fixation of slipped capital femoral epiphysis 1 year ago calls your office to complain of knee pain on the other side. He is able to bear his weight on the leg. You recommend:
Options:
- No sports for 1 month and an office visit if the symptoms continue
- An office visit within the next 2 weeks for evaluation
- C rutches and an office visit within 24 hours
- Magnetic resonance image of the knee and an office visit if the results are abnormal
- Arthroscopy of the knee
Correct Answer: An office visit within the next 2 weeks for evaluation
Explanation:
This patient most likely has a contralateral slipped capital femoral epiphysis. It may even be in the â preslipâ category. Acute progression to an unstable slip is possible at any time and may lead to avascular necrosis and permanent loss of motion. Therefore, urgent examination with physical examination and plain radiographs is necessary.
Question 11:
An 8-year-old boy suffers a hip dislocation while playing tackle football. His hip is reduced by closed means, and he is immobilized in abduction for a month. Radiographs at that time demonstrate a normal appearance of the hip. You recommend:
Options:
- Discharge from follow-up
- Return to all sports and follow-up in 2 months
- No sports and return to clinic in 2 months
- Hip abduction orthosis
- Femoral varus osteotomy
Correct Answer: No sports and return to clinic in 2 months
Explanation:
This patient may suffer avascular necrosis as a result of the dislocation. Avascular necrosis may not become evident until 1 year after the accident, so continued surveillance and protection are recommended.
Question 12:
Which population of patients with cerebral palsy is at greatest risk of neuromuscular hip subluxation:
Options:
- Monoplegics
- Spastic hemiplegics
- Spastic diplegics
- Total-involvement
- Athetoid
Correct Answer: Total-involvement
Explanation:
Patients with total-involvement cerebral palsy are at the greatest risk of hip subluxation. The rate is documented to be between 25% and 60%.
Question 13:
Which group of children with cerebral palsy are at greatest risk of hip subluxation after selective dorsal rhizotomy:
Options:
- Under age 4
- Over age 10
- Spastic diplegics
- Nonambulators
- Spastic hemiplegics
Correct Answer: Nonambulators
Explanation:
Nonambulators with some degree of pre-existing hip migration are at highest risk of hip subluxation after selective dorsal rhizotomy. Patients over the age of 10 and those with hemiplegia are not typically offered selective rhizotomy.
Question 14:
Which of the following muscles is most often preserved during adductor tenotomy for patients with cerebral palsy:
Options:
- Adductor longus
- Adductor brevis
- Gracilis
- Adductor magnus
- Pectineus
Correct Answer: Adductor magnus
Explanation:
Adductor tenotomy performed on patients with cerebral palsy typically involves multiple releases until abduction of more than 60° is obtained. This usually begins with release of the longus, brevis, and gracilis (with the pectineus if necessary). The adductor magnus is almost never released because of its important extensor function.
Question 15:
The parameter most often recommended to follow the reciprocal relationship of the femoral head to the acetabulum in patients with cerebral palsy is known as the:
Options:
- Migration index
- Epiphyseal extrusion index
- Stulberg index
- Acetabular index
- Tonnis index
Correct Answer: Migration index
Explanation:
The migration index (of Reimer) is most commonly used to track the femoral-acetabular relationship in patients with cerebral palsy because it most accurately portrays the progressive migration of the femoral head that may occur. The acetabular index only measures the acetabular response. The epiphyseal extrusion index is used for patients with Perthes disease (where the epiphysis deforms). The Stulberg index is for late outcome of Perthes, and the Tonnis index is for developmental dysplasia of the hip.
Question 16:
The upper limit for a normal migration index in young children is less than:
Options:
Correct Answer: 5%
Explanation:
The migration index (of Reimer) is the percentage of the femoral head lateral to the Perkins line. The index is used to quantify hip migration in patients with cerebral palsy. It is more useful than the center-edge angle because it is a linear variable angle and because the center of the aspherical, immature femoral head may be hard to accurately identify. The upper limit of a normal migration in young children is listed as 25%.
Question 17:
The acetabular sourcil is best described as:
Options:
- The lateral articular border
- The teardrop
- The acetabular angle
- A degenerative osteophyte
- A cyst forming in hip dysplasia
Correct Answer: The lateral articular border
Explanation:
The acetabular sourcil is a lateral articular border, which normally should be downsloping and below the dome of the acetabulum. In dysplastic hips, the femoral head pushes the acetabular sourcil up and gives it an upsloping shape.
Question 18:
In patients with single thoracic idiopathic scoliosis treated with posterior pedicle screw constructs, the distal extent of the fusion may be stopped at which of the following levels with respect to the neutral vertebra and still routinely maintain balance:
Options:
- Three levels above
- Two levels above
- One level above
- One level below
- Two levels below
Correct Answer: One level above
Explanation:
In single thoracic idiopathic scoliosis, the distal extent of the fusion may be stopped at one level above the neutrally rotated vertebra and still maintain trunk balance.
Question 19:
The greatest number of malpractice suits in pediatric orthopedics relates to which diagnosis:
Options:
- Fractures
- C ompartment syndromes
- Spinal deformities
- Tumors
- C ongenital anomalies
Correct Answer: Fractures
Explanation:
The largest number of malpractice claims in pediatric orthopedics relates to fractures. This diagnosis accounts for 77% of all claims, in contrast to 57% for adults. However, the mean amount paid for each claim is lower than other diagnostic groups. Orthopedic surgeons should be aware of the issue when taking care of children with fractures.
Question 20:
For a given femur fracture pattern and age, which method of treatment causes the longest time to union in children ages 6 to 12 years:
Options:
- Traction and cast
- Immediate hip spica
- External fixation
- Flexible nails
- Rigid nails
Correct Answer: External fixation
Explanation:
External fixation produces the longest times to healing, presumably because of load-shielding. The fracture ends may also be distracted.
