Full Question & Answer Text (for Search Engines)
Question 1:
Which of the following physical findings is uncommon in a patient with a unilateral untreated clubfoot:
Options:
- Thin calf
- Loss of prominence of the heel
- Plantar-medial prominence of the talus in the foot
- Medial midfoot crease
- Decreased length of the foot
Correct Answer: Plantar-medial prominence of the talus in the foot
Explanation:
In a patient with unilateral untreated clubfoot, certain findings are apparent when compared with the unaffected foot. Common findings include a thinner calf, shorter-appearing foot, loss of heel prominence, and a medial midfoot crease. The talus is prominent anterolaterally in the foot but not on the plantar-medial side.
Question 2:
Which of the following radiographic findings is present in a varus foot:
Options:
- Increased parallelism of the talus and calcaneus on lateral film
- Superimposition of the anterior portions of the talus and calcaneus on the lateral film
- Increased divergence of the talus and calcaneus on the anteroposterior film
- Increased abduction of the forefoot on the hindfoot
- Increased superimposition of the metatarsal heads on lateral film
Correct Answer: Increased parallelism of the talus and calcaneus on lateral film
Explanation:
Plain radiographs of a foot that is in varus show increased parallelism of the talus and the calcaneus on both the anteroposterior and lateral films. There is decreased superimposition of the talus, the calcaneus, and the metatarsal heads. By contrast, in a valgus foot, there is increased divergence on both the anteroposterior and lateral films.
Question 3:
Although all of the following conditions may present in patients with skeletal dysplasia, which is the only condition that does not have a high frequency of spontaneous improvement:
Options:
- Infantile foramen magnum stenosis in patients with achondroplasia
- Infantile thoracolumbar kyphosis in patients with achondroplasia
- C ervical kyphosis in patients with diastrophic dysplasia
- C ervical kyphosis in patients with Larsen syndrome
- Hypotonia in patients with achondroplasia
Correct Answer: C ervical kyphosis in patients with diastrophic dysplasia
Explanation:
Cervical kyphosis does not improve in patients with Larsen syndrome and may cause myelopathy. Early arthrodesis (posterior only, if not too severe) is indicated. All of the other conditions have a high incidence of spontaneous improvement, so they are most appropriately treated with observation. In a minority of cases, the deformity does not improve and surgery is indicated.
Question 4:
All of the following conditions may affect lower extremities in children. Which one of the conditions does not have a high incidence of spontaneous improvement:
Options:
- Posteromedial bow of the tibia
- C alcaneovalgus foot
- Metatarsus adductus
- Internal tibial torsion
- Anterolateral bowing of the tibia
Correct Answer: Anterolateral bowing of the tibia
Explanation:
Anterolateral bowing of the tibia is usually associated with tibial dysplasia and may progress to pseudarthrosis. Anterolateral bowing of the tibia does not resolve in most patients. Posteromedial bowing of the tibia usually resolves, although there may be a residual shortening of the tibia. All of the other conditions often completely resolve.
Question 5:
The anterior interosseous nerve enables:
Options:
- Sensation and flexion of the thumb and index fingers
- Flexion of the thumb and index fingers
- Flexion of the lateral (ulnar) two fingers
- Flexion and sensation of the ulnar two fingers
- Abduction of the thumb
Correct Answer: Sensation and flexion of the thumb and index fingers
Explanation:
The anterior interosseous nerve does not carry any sensory fibers. The anterior interosseous nerve enables flexion of the thumb (flexor digitorum pollicis) and index fingers (flexor digitorum profundus). This is the most commonly injured nerve in a supracondylar fracture, and it nearly always spontaneously recovers.
Question 6:
Closed reduction without internal fixation is most likely to produce a satisfactory result in which of the following types of supracondylar fracture:
Options:
- An intact posterior hinge and 20° of hyperextension
- An intact lateral hinge and 15° of varus
- Posterior and medial translation with no intact hinge
- Posterior and lateral translation with no intact hinge
- Anterior translation with 10° of varus
Correct Answer: An intact posterior hinge and 20° of hyperextension
Explanation:
There are many options when treating a supracondylar fracture, but a surgeon should always choose the method with the highest percentage of good results for a given fracture. Answer A describes a type II supracondylar fracture with hyperextension and no varus-valgus displacement. The posterior hinge is intact, and it is relatively simple to reduce the fracture with flexion, immobilizing it at 120°. For the other fractures listed as possible answer choices, the reduction as well as the assessment of reduction is more complex. Therefore, most experts would prefer percutaneous fixation of these fractures once reduced.
Question 7:
The highest rate of success in restoring growth after physeal bar resection is found in which location:
Options:
- Proximal femur
- Distal femur
- Proximal tibia
- Distal tibia
- Proximal humerus
Correct Answer: Distal tibia
Explanation:
The highest rate of success after physeal bar resection is found in the distal tibia. The mean growth after resection in the series by Peterson was 93% of that expected, which is greater than the success rates of the other locations. The reasons for this remain speculative but may be due to the more peripheral location of the bar at the ankle, less complex physeal shape, and lower energy of injury. Physeal bars in the proximal femur and humerus are rarely surgically treated.
Question 8:
Which of the following fracture types are most prone to nonunion or refracture in patients with osteogenesis imperfecta:
Options:
- Supracondylar humeral fractures
- Olecranon apophysis fractures
- Supracondylar femur fractures
- Tibial fractures
- C alcaneal fractures
Correct Answer: Olecranon apophysis fractures
Explanation:
Unless they are internally fixed, olecranon fractures are notoriously prone to nonunion or refracture in patients with osteogenesis imperfecta. The remaining fractures can be treated nonoperatively with cast immobilization.
Question 9:
An 11-year-old boy has multiple, hard, tender nodules in his posterior shoulder girdle and paraspinous muscles. He also has a shortened first metatarsal with a delta-shaped first proximal phalanx. The diagnosis is:
Options:
- Dysplasia epiphysialis hemimelica
- Multiple exostoses
- Fibrodysplasia ossificans progressiva
- Myositis ossificans
- Metastatic osteosarcoma
Correct Answer: Fibrodysplasia ossificans progressiva
Explanation:
Fibrodysplasia ossificans progressiva is a disorder of the BMP4 signaling pathway. This condition is characterized by multiple osseous masses occurring in muscle, especially in the dorsal and axial regions. There is also a characteristic dysmorphology of the great toe, consisting of a shortened first metatarsal, delta-shaped phalanx, and some valgus.
Question 10:
Klippel-Trenaunay syndrome is characterized by cutaneous capillary venous malformation, varicose veins, and which of the following:
Options:
- Multiple enchondromas
- Multiple osteochondromas
- Limb hypertrophy
- Seizure disorder
- C ongenital pseudarthrosis of the tibia
Correct Answer: Limb hypertrophy
Explanation:
Klippel-Trenaunay syndrome has three essential features: cutaneous capillary venous malformation, varicose veins, and hypertrophy of the involved limb in length and/or width. The syndrome usually presents before adolescence. The tissue abnormalities typically do not cross the midline, and the entire limb is not uniformly affected.
Question 11:
Which of the following characterizes Russell-Silver syndrome:
Options:
- Hemihypertrophy
- Hemiatrophy
- Acromegaly
- Macrodactyly
- Precocious puberty
Correct Answer: Hemiatrophy
Explanation:
Russell-Silver syndrome is characterized by a small triangular face, hemiatrophy of up to 5 cm, delay in skeletal age, and sometimes a developmental delay. Scoliosis is commonly found in patients with Russell- Silver syndrome.
Question 12:
Macrodactyly is associated with all of the following syndromes except:
Options:
- Neurofibromatosis
- Proteus syndrome
- Klippel-Trenaunay syndrome
- Marfan syndrome
- Multiple enchondromatosis
Correct Answer: Marfan syndrome
Explanation:
Macrodactyly is an increase in length and width of a digit or two adjacent digits. It may be associated with all of the above syndromes except for Marfan syndrome. Macrodactyly is also a common isolated condition.
Question 13:
Which of the following conditions is inherited in an X-linked dominant fashion:
Options:
- Hemophilia A
- Familial hypophosphatemic rickets
- Marfan syndrome
- Prader-Willi syndrome
- Sickle cell anemia
Correct Answer: Familial hypophosphatemic rickets
Explanation:
Familial hypophosphatemic rickets is inherited in an X-linked dominant fashion, meaning that there is an excess of affected females. Hemophilia A is sex-linked recessive like most X-linked conditions (seen primarily in males). Marfan syndrome is autosomal dominant, sickle cell anemia is autosomal recessive, and Prader-Willi syndrome is a partial deletion of chromosome 15.
Question 14:
Which of the following statements is true regarding congenital pseudarthrosis of the tibia:
Options:
- Congenital pseudarthrosis of the tibia is nearly always associated with neurofibromatosis.
- Congenital pseudarthrosis of the tibia usually occurs in the proximal one- third of the tibia.
- Congenital pseudarthrosis of the tibia usually presents with a valgus deformity.
- Congenital pseudarthrosis of the tibia usually presents with an apex- posterior bow.
- The surrounding bone is usually dysplastic.
Correct Answer: The surrounding bone is usually dysplastic.
Explanation:
Congenital pseudarthrosis of the tibia is associated with neurofibromatosis in approximately one-half of patients. It usually occurs in the distal portion of the tibia, presents with a varus position, and an apex-anterior bow. The surrounding bone is usually dysplastic, displaying segments of sclerosis, tapering, and/or cystic changes. The fibula is often dysplastic as well.
Question 15:
Which of the following elements is most critical to the success of the Williams rod procedure (intramedullary rod fixation) for congenital pseudarthrosis of the tibia:
Options:
- Fibular fixation
- Leaving the rod across the ankle at the time of surgery
- Prolonged orthotic protection
- Electrical stimulation
- Ultrasound stimulation
Correct Answer: Fibular fixation
Explanation:
Fixation of the fibula allows shortening and compression of the tibia, as well as providing mechanical stability. Neither leaving the rod across the ankle nor prolonged orthotic protection beyond the initial postoperative period appears to be essential. Electrical stimulation does not have a quantifiable effect on the success of the procedure. Ultrasound has not been studied in this condition.
Question 16:
Which of the following is considered the cutoff for normal loss of C 1-C 2 articular contact in dynamic computed tomography (C T) in normal patients:
Options:
Correct Answer: 80%
Explanation:
Up to 80% loss of contact between the C 1 and C 2 facet joints may be seen in normal patients. Therefore, dynamic C T is an oversensitive test and the dynamic feature does not add to C T in diagnosis.
Question 17:
In the absence of surgery, which of the following gait parameters in children with cerebral palsy tends to remain static with increasing age:
Options:
- Knee range of motion
- Ankle range of motion
- Normalized walking velocity
- Femoral anteversion
- Knee stiffness
Correct Answer: Femoral anteversion
Explanation:
Most parameters of gait deteriorate over time in the absence of intervention in children with cerebral palsy. Knee and ankle range of motion decrease, as does walking velocity when normalized for height. Femoral anteversion remains unchanged. Knee stiffness increases.
Question 18:
In patients with cerebral palsy, which of the following factors usually leads to an improvement in walking ability:
Options:
- Increased body mass index
- Increased external tibial torsion
- Increased age
- Valgus of the ankle
- Alignment of the foot rocker with the line of progression
Correct Answer: Alignment of the foot rocker with the line of progression
Explanation:
Gait in patients with cerebral palsy declines with increases in age, body mass index, external tibial torsion, and significant ankle valgus (due to worsened mechanics of pushoff). Gait is improved by aligning the foot rocker with the line of progression.
Question 19:
Nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) have the following effect on spinal fusion:
Options:
- Increased speed of fusion
- Increased volume of fusion bone
- Decreased bleeding
- Decreased fusion rate
- Unplanned extension of fusion
Correct Answer: Decreased fusion rate
Explanation:
Nonselective NSAIDs have been shown to decrease fusion rates in both animal models and in humans. The mechanism is most likely through an inhibition of cyclooxygenase (C OX)-1 because C OX-2 inhibitors do not show this effect.
Question 20:
The upper-end vertebra for measurement of kyphosis should always be:
Options:
- T1
- T2
- T3
- T4
- The most inclined upper vertebra on the sagittal plane.
Correct Answer: The most inclined upper vertebra on the sagittal plane.
Explanation:
As in measurement of any spinal curve, the upper-end reference is the most inclined upper vertebra. One should carefully select this level and ensure that comparison measurements utilize the same vertebral levels.
