Question 1

In obstetric brachial plexus injury, an indicator of plexus recovery at 3 months is the return of the:

Explanation

Biceps recovery at 3 months is the single most important indicator of recovery in obstetric plexus palsy.

Question 2

A 15-year-old boy presented with inability to elevate his right shoulder and flex his elbow. He sustained a fall from an all-terrain vehicle 8 weeks ago. He landed on the right shoulder and twisted his neck. Radiographs of the skull, chest, cervical and thoracic spine, and shoulder were normal. There was no loss of consciousness, chest pain, or breathing difficulties. The patient was observed in the hospital until stable and referred for follow-up in the hand clinic at 4 weeks. An electromyelogram (EMG) was scheduled. Clinical examination revealed weakness of deltoid, supraspinatus, infraspinatus, teres minor, biceps, brachialis, brachioradialis, and extensor carpi radialis longus. The remainder of his forearm musculature was preserved and he could grasp, release, and pinch. Sensations were decreased along the distribution of the axillary nerve. There was 3 cm wasting of his arm and 2 cm of the forearm. Tinelâ s sign is positive around the clavicle. Hornerâ s signs are absent and his arm lies against the body. The EMG report showed fibrillation potentials in the weak muscles. The patient can now flex his elbow. When asked to demonstrate, he flexes his wrist and pronates his forearm to swing his elbow into flexion. Diagnosis of the condition is:

Explanation

The involved muscles have C 5, C 6 root innervations. Positive Tinelâ s sign, functioning rhomboids and serratus anterior, and the absence of Hornerâ s syndrome rule out a preganglionic lesion. The EMG finding confirms the clinical finding. Subclinical involvement of any other muscle is not shown. Neuropraxia usually recovers in 6 weeks and EMG shows fibrillation, which is inconsistent with neuropraxia. Brachial plexus neuritis, Parsonage-Turner syndrome, has an acute presentation following a painful episode involving the whole arm. There is significant history of a fall in this case.

Question 3

A 15-year-old boy presented with inability to elevate his right shoulder and flex his elbow. He sustained a fall from an all-terrain vehicle 8 weeks ago. He landed on the right shoulder and twisted his neck. Radiographs of the skull, chest, cervical and thoracic spine, and shoulder were normal. There was no loss of consciousness, chest pain, or breathing difficulties. The patient was observed in the hospital until stable and referred for follow-up in the hand clinic at 4 weeks. An electromyelogram (EMG) was scheduled. C linical examination revealed weakness of deltoid, supraspinatus, infraspinatus, teres minor, biceps, brachialis, brachioradialis, and extensor carpi radialis longus. The remainder of his forearm musculature was preserved and he could grasp, release, and pinch. Sensations were decreased along the distribution of the axillary nerve. There was 3-cm wasting of his arm and 2 cm of the forearm. Tinels sign is positive around the clavicle. Hornerâ s signs are absent and his arm lies against the body. The EMG report showed fibrillation potentials in the weak muscles. The patient can now flex his elbow. When asked to demonstrate, he flexes his wrist and pronates his forearm to swing his elbow into flexion. The level of lesion is:

Explanation

The involved muscles have C 5, C 6 root innervations. Positive Tinelâ s sign, functioning rhomboids and serratus anterior, and the absence of Horners syndrome rule out a preganglionic lesion. The EMG finding confirms the clinical finding. Subclinical involvement of any other muscle is not shown. Neuropraxia usually recovers in 6 weeks and EMG shows fibrillation, which is inconsistent with neuropraxia. Brachial plexus neuritis, Parsonage-Turner syndrome, has an acute presentation following a painful episode involving the whole arm. There is significant history of a fall in this case.

Question 4

A 15-year-old boy presented with inability to elevate his right shoulder and flex his elbow. He sustained a fall from an all-terrain vehicle 8 weeks ago. He landed on the right shoulder and twisted his neck. Radiographs of the skull, chest, cervical and thoracic spine, and shoulder were normal. There was no loss of consciousness, chest pain, or breathing difficulties. The patient was observed in the hospital until stable and referred for follow-up in the hand clinic at 4 weeks. An electromyelogram (EMG) was scheduled. C linical examination revealed weakness of deltoid, supraspinatus, infraspinatus, teres minor, biceps, brachialis, brachioradialis, and extensorcarpi radialis longus. The remainder of his forearm musculature was preserved and he could grasp, release, and pinch. Sensations were decreased along the distribution of the axillary nerve. There was 3 cm wasting of his arm and 2 cm of the forearm. Tinelâ s sign is positive around the clavicle. Hornerâ s signs are absent and his arm lies against the body. The EMG report showed fibrillation potentials in the weak muscles. The patient can now flex his elbow. When asked to demonstrate, he flexes his wrist and pronates his forearm to swing his elbow into flexion. The least helpful test in further management of this patient is:

Explanation

Computed tomography scan of the cervical spine will not show the pseudomeningoceles nor provide any information on brachial plexus. Computed tomography may be needed in case of a suspected neck injury but does not form part of a brachial plexus work up.

Question 5

A 15-year-old boy presented with inability to elevate his right shoulder and flex his elbow. He sustained a fall from an all-terrain vehicle 8 weeks ago. He landed on the right shoulder and twisted his neck. Radiographs of the skull, chest, cervical and thoracic spine, and shoulder were normal. There was no loss of consciousness, chest pain, or breathing difficulties. The patient was observed in the hospital until stable and referred for follow-up in the hand clinic at 4 weeks. An electromyelogram (EMG) was scheduled. C linical examination revealed weakness of deltoid, supraspinatus, infraspinatus, teres minor, biceps, brachialis, brachioradialis, and extensor carpi radialis longus. The remainder of his forearm musculature was preserved and he could grasp, release, and pinch. Sensations were decreased along the distribution of the axillary nerve. There was 3 cm wasting of his arm and 2 cm of the forearm. Tinelâ s sign is positive around the clavicle. Hornerâ s signs are absent and his arm lies against the body. The EMG report showed fibrillation potentials in the weak muscles. The patient can now flex his elbow. When asked to demonstrate, he flexes his wrist and pronates his forearm to swing his elbow into flexion. The plan of management in this patient 5 months postinjury with no clinical improvement should be:

Explanation

Neurotization is appropriate in preganglionic lesions. If at 6 months a patient shows no evidence of recovery, it is time for plexus exploration. Further observation will not change the picture. Tendon transfers are reconstructive procedures, which are done at a later stage.

Question 6

A 15-year-old boy presented with inability to elevate his right shoulder and flex his elbow. He sustained a fall from an all-terrain vehicle 8 weeks ago. He landed on the right shoulder and twisted his neck. Radiographs of the skull, chest, cervical and thoracic spine, and shoulder were normal. There was no loss of consciousness, chest pain, or breathing difficulties. The patient was observed in the hospital until stable and referred for follow-up in the hand clinic at 4 weeks. An electromyelogram (EMG) was scheduled. C linical examination revealed weakness of deltoid, supraspinatus, infraspinatus, teres minor, biceps, brachialis, brachioradialis, and extensor carpi radialis longus. The remainder of his forearm musculature was preserved and he could grasp, release, and pinch. Sensations were decreased along the distribution of the axillary nerve. There was 3 cm wasting of his arm and 2 cm of the forearm. Tinelâ s sign is positive around the clavicle. Horners signs are absent and his arm lies against the body. The EMG report showed fibrillation potentials in the weak muscles. The patient can now flex his elbow. When asked to demonstrate, he flexes his wrist and pronates his forearm to swing his elbow into flexion. The most important indication for early exploration in this patient is:

Explanation

An important indication for early exploration is the recovery of a distally supplied muscle, EC RL C 6, in the absence of a proximally supplied muscle, bicepsâ C 5. Trick movements are adaptive movements employed by the patient by recruiting other muscles, for example, the use of flexor- pronator as elbow flexors in this patient. Bony deformity is a late sequelae and biceps recovery at 3 months is important in obstetric brachial palsy.

Question 7

A 15-year-old boy presented with inability to elevate his right shoulder and flex his elbow. He sustained a fall from an all-terrain vehicle eight weeks prior. He landed on the right shoulder and twisted his neck. Radiographs of the skull, chest, cervical and thoracic spine, and shoulder were normal. There was no loss of consciousness, chest pain, or breathing difficulties. The patient was observed in the hospital until stable and referred for follow-up in the hand clinic at 4 weeks. An electromyelogram (EMG) was scheduled. C linical examination revealed weakness of deltoid, supraspinatus, infraspinatus, teres minor, biceps, brachialis, brachioradialis, and extensor carpi radialis longus. The remainder of his forearm musculature was preserved and he could grasp, release, and pinch. Sensations were decreased along the distribution of the axillary nerve. There was 3-cm wasting of his arm and 2 cm of the forearm. Tinelâ s sign is positive around the clavicle. Hornerâ s signs are absent and his arm lies against the body. The EMG report showed fibrillation potentials in the weak muscles. The patient can now flex his elbow. When asked to demonstrate, he flexes his wrist and pronates his forearm to swing his elbow into flexion. The most important function that needs to be restored in this patient is:

Explanation

Elbow flexion is central to management of brachial plexus management because it serves the most important function of feeding.

Question 8

An 18-month-old boy presents with a clawing deformity of the right hand. He was born full term after a difficult delivery complicated by shoulder dystocia. He weighed 9.5 lbs at birth. The patient had a brief episode of apnea with an APGAR score of 5 at birth and needed resuscitation and admission to the neonatal intensive care unit. A tender bump was noted on the patients right clavicle, which was diagnosed as clavicle fracture. A week later, the patient could not flex the fingers of his right hand. The neonatologist informed the parents that the fracture was managed conservatively and the absence of finger flexion was due to fracture and would recover. However, recovery can be prolonged and may take up to two years. The patient has grown and his immunization is complete. His right hand has extension at all the metacarpal joints of the fingers while the proximal interphalangeal and distal interphalangeal joints are flexed. The thumb is in an adducted position, and it is difficult to passively bring the thumb to full abduction. There is obvious wasting of the hand and forearm. The patient moves the arm well with no abnormalities noticed at the shoulder, elbow, and wrist. Radiograph of the chest shows a healed clavicle fracture with no evidence of diaphragmatic paralysis. There is no evidence of Hornerâ s syndrome and the grasp reflex is absent. Diagnosis of this condition is:

Explanation

This is a case of obstetric brachial plexus injury involving the C 8, T1 roots (Klumpkeâ s palsy). Erbâ s palsy involves upper roots only. C ombined nerve injuries can present in a similar fashion, however low ulnar and median nerve lesions will not have weakness of the flexor digitorum profundus and flexor digitorum sublimis. History of a large baby, shoulder dystocia, and clavicle fracture point to difficult labor. The most common type of brachial plexus injury related to birth is Erbâ s palsy, which is usually associated with a breech presentation. Isolated Klumpkeâ s palsy is quite rare and the involvement of C 8 and T1 usually occurs as part of global plexus injury.

Question 9

An 18-month-old boy presents with a clawing deformity of the right hand. He was born full term after a difficult delivery complicated by shoulder dystocia. He weighed 9.5 lbs at birth. The patient had a brief episode of apnea with an APGAR score of 5 at birth and needed resuscitation and admission to the neonatal intensive care unit. A tender bump was noted on the patients right clavicle, which was diagnosed as clavicle fracture. A week later, the patient could not flex the fingers of his right hand. The neonatologist informed the parents that the fracture was managed conservatively and the absence of finger flexion was due to fracture and would recover. However, recovery can be prolonged and may take up to two years. The patient has grown and his immunization is complete. His right hand has extension at all the metacarpal joints of the fingers while the proximal interphalangeal and distal interphalangeal joints are flexed. The thumb is in an adducted position, and it is difficult to passively bring the thumb to full abduction. There is obvious wasting of the hand and forearm. The patient moves the arm well with no abnormalities noticed at the shoulder, elbow, and wrist. Radiograph of the chest shows a healed clavicle fracture with no evidence of diaphragmatic paralysis. There is no evidence of Horners syndrome and the grasp reflex is absent. The level of the lesion in this patient is:

Explanation

It is difficult to clinically differentiate between a pre- and postganglionic lesion of C 8, T1 in a child. Absence of Hornerâ s syndrome and hemi- diaphragmatic palsy in this case indicates that this is not a preganglionic lesion. The ability of the patient to hold his head suggests that the paravertebral muscles are functional, as is true in postganglionic lesions.

Question 10

An 18-month-old boy presents with a clawing deformity of the right hand. He was born full term after a difficult delivery complicated by shoulder dystocia. He weighed 9.5 lbs at birth. The patient had a brief episode of apnea with an APGAR score of 5 at birth and needed resuscitation and admission to the neonatal intensive care unit. A tender bump was noted on the patients right clavicle, which was diagnosed as clavicle fracture. A week later, the patient could not flex the fingers of his right hand. The neonatologist informed the parents that the fracture was managed conservatively and the absence of finger flexion was due to fracture and would recover. However, recovery can be prolonged and may take up to two years. The patient has grown and his immunization is complete. His right hand has extension at all the metacarpal joints of the fingers while the proximal interphalangeal and distal interphalangeal joints are flexed. The thumb is in an adducted position, and it is difficult to passively bring the thumb to full abduction. There is obvious wasting of the hand and forearm. The patient moves the arm well with no abnormalities noticed at the shoulder, elbow, and wrist. Radiograph of the chest shows a healed clavicle fracture with no evidence of diaphragmatic paralysis. There is no evidence of Horners syndrome and the grasp reflex is absent. Appropriate surgical management in this case is:

Explanation

Neurotization is done for preganglionic lesions and has not been shown to produce successful results for lower root involvement. At 18 months, exploration and nerve grafting must be carried out. Neurolysis is reserved for cases in which recovery is partial or plateaus. Tendon transfers in children less than 3 years old do not work as well. Younger children do not cooperate well in rehabilitation. It is also difficult to decide upon the functioning motors for transfer.

Question 11

An 18-month-old boy presents with a clawing deformity of the right hand. He was born full term after a difficult delivery complicated by shoulder dystocia. He weighed 9.5 lbs at birth. The patient had a brief episode of apnea with an APGAR score of 5 at birth and needed resuscitation and admission to the neonatal intensive care unit. A tender bump was noted on the patients right clavicle, which was diagnosed as clavicle fracture. A week later, the patient could not flex the fingers of his right hand. The neonatologist informed the parents that the fracture was managed conservatively and the absence of finger flexion was due to fracture and would recover. However, recovery can be prolonged and may take up to two years. The patient has grown and his immunization is complete. His right hand has extension at all the metacarpal joints of the fingers while the proximal interphalangeal and distal interphalangeal joints are flexed. The thumb is in an adducted position, and it is difficult to passively bring the thumb to full abduction. There is obvious wasting of the hand and forearm. The patient moves the arm well with no abnormalities noticed at the shoulder, elbow, and wrist. Radiograph of the chest shows a healed clavicle fracture with no evidence of diaphragmatic paralysis. There is no evidence of Hornerâ s syndrome and the grasp reflex is absent. Reconstructive surgery includes all of the following except:

Explanation

This patient has developed contractures of first web space, which will not respond to passive stretching. Fusion of the MP joint is unneccesary, as tendon transfers will provide lateral and tip pinch as well as opposition.

Question 12

Which mechanism and long-term deformity is most often associated with a dorsal avulsion fracture at the base of the middle phalanx:

Explanation

Three types of PIP joint dislocations are identified: volar, dorsal, and central depression. Volar PIP joint dislocations result in avulsion of the dorsal fragment of the base of the middle phalanx, which represents the central tendons attachment. If displacement persists, than a boutonniere deformity may result. Volar avulsion fractures of the PIP joint are often due to a hyperextension injury at the attachment of the volar plate.

Question 13

At what degree of flexion is ulnar collateral ligament injury tested:

Explanation

At 30º of MCP joint flexion, the ulnar collateral ligament is isolated from the volar plate.

Question 14

Which of the following structures are found within the first dorsal compartment:

Explanation

The first dorsal compartment encompasses the abductor pollicis longus and extensor pollicis brevis. Multiple slips of abductor pollicus brevis may be present, which is important in de Quervainâ s release.

Question 15

A 28-year-old man fell off his bike and sustained a fall onto his outstretched hand. He experiences thumb and index finger numbness. Attempts at reduction of his grade I open extra-articular distal radius fracture are unsuccessful. The next appropriate step of management is:

Explanation

A patient with this injury represents a high-energy fracture in a high demand individual. The patient will require incision and drainage of his open wound, open reduction with internal fixation, and carpal tunnel release. Bone grafting would not be appropriate in a patient with open fracture.

Question 16

Which of the following is not usually associated with radial deficiency:

Explanation

Patients with thrombocytopenia absent radii, Fanconi anemia, Holt-Oram syndrome, and cardiac anomolies all are associated with radial deficiency. Larsen syndrome is associated with multiple, larger joint dislocation.

Question 17

Which of the following is the most common carpal coalition in the hand:

Explanation

Lunotriquetral coalition has a 1.6% prevalence in the general population. The second most common coalition is the capitohamate. Incomplete coalition is treated by arthrodesis of the lunotriquetral joint.

Question 18

A 6-year-old boy presents with a Salter-Harris II distal radius fracture 3 weeks after injury. He is nontender and neurologically intact. On radiographs, he has a 35Âº dorsal angulation. The appropriate course of treatment is:

Explanation

For a patient with delayed presentation of a distal radius fracture, appropriate management includes casting and observation for at least 2 years to assess physeal damage and remodeling. The patient may require osteotomy if remodeling does not occur.

Question 19

The oblique retinacular ligament connects with what two structures:

Explanation

Landsmeer (oblique retinacular ligament) runs from the flexor tendon sheath of the proximal phalanx to the lateral extensor tendon as they insert onto the base of the proximal phalanx. A stay or retaining ligament maintains centralization of the extensor tendons.

Question 20

A patient presents with hand weakness. On examination, she has no sensory deficient, decreased strength with pronation, and her elbow is at 90º of flexion and pulp-to-pulp contact on key pinch. The most likely diagnosis is:

Explanation

Anterior interosseous nerve syndrome is due to compression of the anterior interosseous nerve (AIN) in the forearm by lacterus fibrosis, flexor digitorum superficialis, or pronator teres. The AIN innervates the pronator quadratus, flexor digitorum profundus (FDP) to the index finger and the flexor pollicis longus (FPL). Anatomy variation exists where the AIN may innervate part of the flexor digitorum superficialis. In this patient, she has decreased pronation at 90º flexion, which relaxes the humeral attachment of the pronator from the pronator quadrus weakness. She also has pulp-to-pulp contract due to weakness of the FPL and FDP to the index finger.

Question 21

Indications for operative treatment in an acute elbow dislocation include:

Explanation

Recurrent dislocations with extension past 50° represent a significant injury to the elbow and require a stabilization period. Instability to valgus stress represents injury to the anterior band of the medial collateral ligament of the elbow and will heal with protected motion. The majority of radial head fractures (Mason type I and II) that are less than 30º of the radial head and less than 30º angulation heal with good functional results. Most dislocations will have osteochondral lesions. Ulnar nerve parathesias can be associated with dislocations but is not an indication for operative fixation.

Question 22

When performing open reduction and internal fixation of radial neck fractures, the plate should be placed:

Explanation

The "nonarticular safe-zone" comprising only 90Âº of the radial head circumference is achieved by placing the plate posterior with the arm in supination.

Question 23

Heterotopic ossification after elbow dislocations is not associated with which of the following:

Explanation

Heterotopic ossification is commonly associated with delay of surgical intervention, closed head injury, aggressive passive range of motion after dislocation, and extensive surgical dissection. Radiographic evidence of heterotopic ossification is present in 75% of patients with elbow dislocations but only 5% of these are clinically significant.

Question 24

What is the order of joint destruction in a patient with scapholunate disassociation:

Explanation

Patients with scapholunate disassociation can develop a scapholunate advanced collapsed wrist. The progression is from the radial styloid to proximal radioscaphoid, to midcarpal (capitolunate). The lunate is extended and unloaded due to its concentric design, which results in preservation of the radiolunate.

Question 25

Which of the following is not characteristic of Dupuytrenâ s disease:

Explanation

Dupuytrens disease is characteristically unpredictable in its clinical progression. It may spontaneously resolve or quickly to advanced disease.

Question 26

Operative indications for Dupuytrenâ s contracture include:

Explanation

As a general guideline the "table test" is used as an indication for operative intervention. If the patient cannot lay his/her hand flat onto a table, the disease has usually progressed to the point where surgery is required. A metacarpophalangeal joint contracture of 30º to 40º or a proximal interphalangeal joint contracture of 30º or more is an indication for surgery.

Question 27

Favorable indications for attempted replantation include:

Explanation

Favorable indications for replantation include thumb amputations because of the functional importance of the thumb. Warm ischemias less than 8 hours or cold ischemia time less than 16 hours are more favorable for replantation.

Question 28

Injuries to the central articular disk portion of the triangular fibrocartilage complex are related to all of the following except:

Explanation

Scaphoid nonunion is not related to central triangular fibrocartilage complex injuries. A positive ulnar variance is most strongly associated with triangular fibrocartilage complex central disk injuries.

Question 29

All of the following transfers may be used to improve function in a patient who has had radial nerve paralysis longer than 6 months, except:

Explanation

Radial nerve paralysis is a common injury, and many patients recover after repair. Tendon transfers should be delayed until sufficient time for reinnervation has passed. Pronator to extensor carpi radialis brevis can be performed at time of nerve repair to provide wrist extension and grasp during period of nerve recovery. Transfers for radial nerve palsy need to address wrist extension, thumb extension, and finger extenstion. All of the above transfer would provide these functions except a transfer to the brachioradialis.

Question 30

A 24-year-old man presents with a short forearm and a hand deformity. The patient is otherwise healthy with no other congenital defects. The clinical appearance of his forearm is shown (Slide). Your diagnosis is:

Explanation

This is a classic appearance of a radial club hand, which is often referred to as preaxial longitudinal deficiency. Ulnar club hand and postaxial longitudinal deficiency are synonymous.

Question 31

A 24-year-old man presents with a short forearm and a hand deformity. The patient is otherwise healthy with no other congenital defects. The clinical appearance of his forearm is shown (Slide). The patient has an elbow flexion contracture of 70° and desires lengthening. Which of the following statements is not true regarding lengthening:

Explanation

In most cases of radial club hand, excluding a hypoplastic radius, full correction cannot be achieved. Orthopedic Prometric Exam Question

Question 32

A 24-year-old man presents with a short forearm and a hand deformity. The patient is otherwise healthy with no other congenital defects. The clinical appearance of his forearm is shown (Slide). The potential complications of lengthening are discussed, and the patient is advised against it. However, the elbow flexion contracture is corrected by gradual distraction. One year postoperatively, the patient has attained a 30° correction of the flexion deformity, which remains mobile. Now, he desires that his wrist deformity be corrected. The procedure of choice is:

Explanation

Wrist arthrodesis is the best solution for this patient and his recurrent deformity because it provides a stable platform for grasp.C orrect Answer: Arthrodesis

Question 33

A 24-year-old man presents with a short forearm and a hand deformity. The patient is otherwise healthy with no other congenital defects. The clinical appearance of his forearm is shown (Slide). Although the patient has a thumb, it is in an abnormal position. Any attempt to make his thumb more functional will be influenced by:

Explanation

The pattern of usage of the hand is established in the brain by 2 to 3 years of age. Although pollicization has been performed in adolescents, patients continue to prefer a scissor pinch. At 24 years of age, this pattern will be well established. The patient can be coaxed to use his thumb, but it will not be involuntary and automatic.C orrect Answer: Presence of a side-to-side finger grip

Question 34

A radial club hand is the result of an insult during which phase of the gestation period:

Explanation

A radial club hand is the result of an insult during weeks 4 to 7 of gestation.

Question 35

A 15-day-old boy presents with deformity of the right hand. The boy was delivered prematurely and underwent an urgent arterial switch for transposition of great vessels. The patient is in stable condition. He has a radial club hand, and because the radial head cannot be palpated, total absence of radius is suspected. The thumb is absent and the index finger has camptodactyly. The forearm is short compared to the left side, and the patient flexes his elbow upon stimulation. Spontaneous finger motion is also present. A thorough physical examination is performed and a set of investigations is ordered. The results are as follows: complete blood count 10,000 mcu/L; platelet 254 254×103 mcu/L; neutophils 50%; Hb 14.2 mg/dL; lymphocytes 40%; Hct 45; and monocytes 10%. No renal abnormalities were noted on ultrasonogram of the abdomen. A radiograph of the spine is normal. Diagnosis is:

Explanation

The patient has a radial club hand with a cardiac defect. Because the spine radiograph is normal, the diagnosis cannot be VATER or VAC TERL anomaly as both involve vertebrae. Blood work up is normal, making this diagnosis Holt-Oram syndrome.

Question 36

The principal abnormality associated with Holt-Oram syndrome is:

Explanation

Holt-Oram syndrome is associated with cardiac defects. The most common defect is aldosterone secretion.

Question 37

The hereditary pattern for Holt-Oram syndrome is:

Explanation

Holt-Oram syndrome is inherited in an autosomal dominant manner.

Question 38

A 15-day-old boy presents with deformity of the right hand. The boy was delivered prematurely and underwent an urgent arterial switch for transposition of great vessels. The patient is in stable condition. He has a radial club hand, and because the radial head cannot be palpated, total absence of radius is suspected. The thumb is absent and the index finger has camptodactyly. The forearm is short compared to the left side, and the patient flexes his elbow upon stimulation. Spontaneous finger motion is also present. A thorough physical examination is performed and a set of investigations is ordered. The results are as follows: complete blood count 10,000 mcu/L; 254×103 mcu/L; neutophils 50%; Hb 14.2 mg/dL; lymphocytes 40%; Hct 45; and monocytes 10%. No renal abnormalities were noted on ultrasonogram of the abdomen. A radiograph of the spine is normal. The next step in the management of the radial club hand is:

Explanation

For the first 6 to 9 months, parents and therapists perform passive stretching. Serial casting and splinting may also be used. Sometimes, preoperative soft-tissue distraction is performed, usually before a wrist stabilization procedure. Correct Answer : Stretching

Question 39

A 15-day-old boy presents with deformity of the right hand. The boy was delivered prematurely and underwent an urgent arterial switch for transposition of great vessels. The patient is in stable condition. He has a radial club hand, and because the radial head cannot be palpated, total absence of radius is suspected. The thumb is absent and the index finger has camptodactyly. The forearm is short compared to the left side, and the patient flexes his elbow upon stimulation. Spontaneous finger motion is also present. A thorough physical examination is performed and a set of investigations is ordered. The results are as follows: complete blood count 10,000 mcu/L; platelet 254×103 mcu/L; neutophils 50%; Hb 14.2 mg/dL; lymphocytes 40%; Hct 45; and monocytes 10%. No renal abnormalities were noted on ultrasonogram of the abdomen. A radiograph of the spine is normal. Centralization will be performed on the patient. All of the following statements are true about centralization except:

Explanation

In a centralization procedure, the forearm is aligned with the third metacarpal, not the second.

Question 40

A 15-day-old boy presents with deformity of the right hand. The boy was delivered prematurely and underwent an urgent arterial switch for transposition of great vessels. The patient is in stable condition. He has a radial club hand, and because the radial head cannot be palpated, total absence of radius is suspected. The thumb is absent and the index finger has camptodactyly. The forearm is short compared to the left side, and the patient flexes his elbow upon stimulation. Spontaneous finger motion is also present. A thorough physical examination is performed and a set of investigations is ordered. The results are as follows: complete blood count 10,000 mcu/L; 254 103 mcu/L; neutophils 50%; Hb 14.2 mg/dL; lymphocytes 40%; Hct 45; and monocytes 10%. No renal abnormalities were noted on ultrasonogram of the abdomen. A radiograph of the spine is normal. When the patient is 10 years old, he is not satisfied with the length of his forearm and wishes to lengthen it. Which of the following is not a satisfactory recommendation:

Explanation

Acute lengthening is done for small defects and, if performed in this patient, may result in severe neurovascular compromise.

Question 41

Which of the following conditions is present in patients with radial club hand but not in patients with ulnar club hand:

Explanation

Ulnar club hand differs from radial club hand in that cardiopulmonary, hematopoeitic, gastrointestinal, and genitourinary anomalies are uncommon.

Question 42

All of the following developmental anomalies are associated with ulnar club hand except:

Explanation

Atrial septal defects are developmental abnormalities present in patients with radial club hand or Holt-Oram syndrome.

Question 43

Which of the following syndromes is associated with ulnar club hand:

Explanation

VATER, VAC TERL, Holt-Oram syndrome, and TAR syndrome are associated with radial club hand. Femur-fibular-ulnar syndrome is characterized by proximal femoral focal deficiency, fibular agenesis, and ulnar ray defects.

Question 44

Which of the following areas is not involved in ulnar club hand:

Explanation

Vertebrae are usually not involved in ulnar club hand.

Question 45

All of the following are true statements regarding elbow involvement in ulnar club hand except:

Explanation

Elbow instability does not correspond with severity of involvement. Fifty percent of patients with total aplasia have radiohumeral synostosis, which provides adequate stability.

Question 46

All of the following statements are true regarding the carpal bones in patients with ulnar club hand except:

Explanation

A notch is often created in centralization procedures for radial club hand. Wrist stabilization procedures are not performed for ulnar club hand.

Question 47

All of the following anomalies are present in patients with ulnar club hand except:

Explanation

Vertebral anomalies are not common in patients with ulnar club hand.

Question 48

A 1-year-old boy was born full-term and pregnancy was uneventful. However, the parents noticed deformity of the patientâ s forearm, which progressed with growth. The parents consulted a pediatric orthopaedic surgeon 4 months prior and were advised to observe the growth. Multiple investigations in the form of two-dimensional echogram, abdomen ultrasonography, radiographs of the spine, and complete blood work did not reveal any abnormalities. No genetic or syndromic abnormality was reported. A radiograph taken 4 months prior is shown.

Explanation

The ulnar deficiency is longitudinal and the ulna is considered a postaxial bone. Ulnar agenesis means absence while radial club hand is a pre-axial longitudinal deficiency and cleft hand is a central deficiency.

Question 49

A 45-year-old man presents with marked lateral elbow pain. He says that the pain has been present for 3 weeks. He has no history of recent trauma. He is an avid tennis player, and he feels increased pain after playing tennis and when doing wrist extension exercises in the gym. His pain is maximally reproduced with resisted middle finger extension and with forearm supination with the elbow extended. Electromyography would confirm the diagnosis as:

Explanation

The clinical picture is similar to that of lateral epicondylitis. However, the maximal tenderness is slightly more distal, just beyond the radial head. Diagnosis may be confirmed using provocative maneuvers (resisted middle finger extension or forearm supination with the elbow extended) or with electromyography.

Question 50

A 45-year-old man presents with marked lateral elbow pain. He says that the pain has been present for 3 weeks. He has no history of recent trauma. He is an avid tennis player, and he feels increased pain after playing tennis and when doing wrist extension exercises in the gym. His pain is maximally reproduced with resisted middle finger extension and with forearm supination with the elbow extended. Which of the following is the appropriate initial treatment:

Explanation

Ninety to 95% of all patients with tennis elbow respond to nonoperative treatment, which should always be tried first. Treatment begins with a period of rest, ice, and nonsteroidal anti-inflammatory medications.

Question 51

A 24-year-old motorcyclist sustains a traction injury to his right brachial plexus. Exam shows absent shoulder abduction, elbow flexion, and wrist extension. Sensation is absent in the C5, C6, and C7 dermatomes. Sensory nerve action potentials (SNAPs) for the median and radial nerves are normal in the right upper extremity. What does this indicate?

Explanation

Intact SNAPs in the presence of clinical anesthesia indicate a preganglionic lesion (root avulsion). The dorsal root ganglion is intact and connected to the peripheral nerve, maintaining the sensory axon despite loss of central connection.

Question 52

A 32-year-old woman presents with knee pain. Radiographs show an eccentric, lytic epiphyseal lesion in the distal femur. Biopsy reveals mononuclear cells and multinucleated giant cells.

What is the most appropriate definitive management?

Explanation

The clinical and radiographic picture suggests a Giant Cell Tumor of bone. Extended intralesional curettage using a high-speed burr and adjuvants (like phenol or liquid nitrogen) followed by PMMA or bone graft is the standard treatment.

Question 53

A 4-month-old girl is placed in a Pavlik harness for developmental dysplasia of the hip. At a follow-up visit 2 weeks later, the parents report the infant has stopped kicking her left leg. On exam, she lacks active knee extension on the left. What is the most likely cause?

Explanation

Excessive hip flexion in a Pavlik harness can compress the femoral nerve against the inguinal ligament. Treatment involves loosening the anterior straps or temporarily discontinuing the harness.

Question 54

A 45-year-old male is brought to the ED after a crush injury. He is hemodynamically unstable with a blood pressure of 75/40 mmHg. Radiographs show an anteroposterior compression (APC) type III pelvic ring injury. A pelvic binder is applied. To maximize biomechanical efficacy, the binder should be centered over which anatomic landmark?

Explanation

Pelvic binders are most effective at reducing pelvic volume when centered directly over the greater trochanters. Placement over the iliac crests is less effective and can sometimes worsen the deformity by externally rotating the hemipelvis.

Question 55

A 13-year-old gymnast presents with progressive lower back pain. Radiographs reveal a grade III L5-S1 isthmic spondylolisthesis. She has failed conservative management and reports radicular pain in the L5 distribution. What is the recommended surgical intervention?

Explanation

High-grade (Grade III-V) isthmic spondylolisthesis in adolescents typically requires surgical stabilization. L5-S1 posterior fusion with instrumentation is the standard approach, with or without partial reduction depending on the slip angle and surgeon preference.

Question 56

A 65-year-old man presents with groin pain 8 years after a metal-on-metal total hip arthroplasty. Aspiration yields cloudy fluid with negative cultures.

Histology of the periprosthetic tissue is most likely to show:

Explanation

The scenario describes an adverse local tissue reaction (ALTR) or ALVAL associated with metal-on-metal implants. Histologically, this is characterized by an aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) with extensive tissue necrosis.

Question 57

During the surgical repair of a "terrible triad" injury of the elbow, which of the following sequences is the standard algorithm for reconstruction?

Explanation

The standard surgical algorithm for a terrible triad injury works deep to superficial: repair the coronoid first, then fix or replace the radial head, and finally repair the lateral ulnar collateral ligament (LUCL).

Question 58

A patient presents with inability to actively flex the distal interphalangeal joint of the index finger and the interphalangeal joint of the thumb. To differentiate Anterior Interosseous Nerve (AIN) syndrome from flexor tendon rupture, which finding is pathognomonic for AIN syndrome?

Explanation

AIN syndrome causes weakness of the FPL, FDP to the index/long fingers, and pronator quadratus. The tenodesis effect remains intact because the tendon is continuous, unlike in a flexor tendon rupture.

Question 59

A 13-year-old obese boy presents with a 3-week history of right groin pain and a limp. He walks with an externally rotated foot. AP and frog-leg lateral pelvis radiographs confirm a mild stable slipped capital femoral epiphysis (SCFE) on the right. What is the most appropriate management?

Explanation

The gold standard treatment for a stable SCFE is in situ pinning with a single, centrally placed cannulated screw. Attempting closed reduction increases the risk of avascular necrosis.

Question 60

Bone morphogenetic proteins (BMPs) are used to enhance bone healing. Which of the following BMPs is an FDA-approved osteoinductive agent commonly used in anterior lumbar interbody fusion?

Explanation

Recombinant human BMP-2 (rhBMP-2) is heavily utilized and FDA-approved for specific spinal fusions, including ALIF with a specific cage. BMP-2 and BMP-7 are the primary osteoinductive BMPs used clinically.

Question 61

A 25-year-old overhead athlete presents with deep shoulder pain. MR arthrogram reveals a type II SLAP tear. During arthroscopy, a "peel-back" lesion is noted. This mechanism primarily involves which force applied to the biceps anchor during the late cocking phase of throwing?

Explanation

The "peel-back" mechanism occurs during the late cocking phase of throwing when the shoulder is maximally abducted and externally rotated. This places a torsional force on the biceps root, causing it to peel back from the posterior superior glenoid.

Question 62

A 70-year-old woman undergoes a right total knee arthroplasty. During the trial phase, the knee is stable in extension but opens symmetrically on the medial and lateral sides by 4 mm in flexion. What is the most appropriate surgical adjustment?

Explanation

Symmetrical laxity in flexion with stability in extension indicates a loose flexion gap. This is best managed by upsizing the femoral component (increasing the anteroposterior dimension) or translating it slightly posteriorly, without altering the extension gap.

Question 63

A 62-year-old man presents with dropping objects and a stiff gait. Exam shows hyperreflexia in the lower extremities and a positive Hoffmann sign.

T2-weighted MRI of the cervical spine is most likely to demonstrate which of the following?

Explanation

The clinical presentation is classic for cervical spondylotic myelopathy. MRI typically shows spinal stenosis and may show high T2 signal intensity within the cord, reflecting edema, myelomalacia, or gliosis at the level of compression.

Question 64

A 25-year-old male presents with a complete C5-C6 root avulsion following a motorcycle accident 3 months ago. Clinical examination demonstrates absent elbow flexion and shoulder abduction, with preserved hand function. What is the most appropriate nerve transfer to restore active elbow flexion in this patient?

Explanation

The Oberlin transfer involves transferring a fascicle of the ulnar nerve (and often the median nerve in a double transfer) to the motor branches of the biceps and brachialis. It is highly effective for restoring elbow flexion in upper trunk (C5-C6) avulsion injuries because the ulnar nerve (C8-T1) remains intact.

Question 65

A 6-week-old infant is being treated with a Pavlik harness for developmental dysplasia of the hip. At the 2-week follow-up, the mother reports the infant has stopped kicking the affected leg. On examination, active knee extension is absent but ankle movements are preserved. What is the most likely cause of this complication?

Explanation

Femoral nerve palsy in a Pavlik harness is typically caused by excessive hip hyperflexion, which compresses the nerve against the inguinal ligament. Treatment involves loosening the anterior straps or temporarily removing the harness until nerve function returns.

Question 66

An 8-year-old child sustains a displaced extension-type supracondylar fracture of the humerus. After closed reduction and percutaneous pinning, examination reveals an inability to flex the interphalangeal joint of the thumb and the distal interphalangeal joint of the index finger. Which nerve structure is most likely injured?

Explanation

The anterior interosseous nerve (AIN) is the most commonly injured nerve in extension-type supracondylar humeral fractures. It innervates the flexor pollicis longus and the radial half of the flexor digitorum profundus, leading to the inability to make an "OK" sign.

Question 67

A 22-year-old man presents with wrist pain after a fall on an outstretched hand. Radiographs confirm a displaced fracture of the proximal pole of the scaphoid. The high risk of avascular necrosis and nonunion in this region is primarily due to the blood supply originating from branches of the:

Explanation

The scaphoid receives its primary blood supply from the dorsal carpal branch of the radial artery, which enters the distal pole and flows in a retrograde fashion to the proximal pole. Fractures at the waist or proximal pole disrupt this delicate supply, predisposing to avascular necrosis.

Question 68

A 45-year-old man presents with acute onset of severe lower back pain, bilateral sciatica, saddle anesthesia, and urinary retention following a heavy lifting episode. MRI reveals a massive L4-L5 central disc herniation. What is the most critical next step in management?

Explanation

This patient presents with Cauda Equina Syndrome, an absolute surgical emergency. Urgent surgical decompression, ideally within 24 to 48 hours, is required to optimize the recovery of bowel, bladder, and sexual function.

Question 69

A 12-year-old boy presents with progressive knee pain and swelling. Radiographs show a destructive, permeative metaphyseal lesion in the distal femur with a "sunburst" periosteal reaction and Codman's triangle. Histological examination reveals malignant spindle cells producing osteoid matrix. What is the most likely diagnosis?

Explanation

Osteosarcoma classically presents in the metaphysis of long bones in adolescents with a sunburst periosteal reaction and Codman's triangle. The histological hallmark is the production of malignant osteoid by the tumor cells.

Question 70

During a posterior approach for a total hip arthroplasty, the surgeon meticulously repairs the short external rotators and the posterior capsule to the greater trochanter. This specific closure is primarily performed to reduce the risk of which postoperative complication?

Explanation

A meticulous posterior capsular and short external rotator repair significantly decreases the incidence of posterior dislocation following a total hip arthroplasty performed via the posterior approach.

Question 71

An 80-year-old female sustains a fall and complains of severe left hip pain. Radiographs reveal an intracapsular femoral neck fracture with complete displacement and no continuity of the trabecular lines. According to the Garden classification, this represents:

Explanation

The Garden classification assesses femoral neck fractures. Garden I is incomplete/valgus impacted, Garden II is complete but nondisplaced, Garden III is completely fractured with partial displacement, and Garden IV is completely displaced with no trabecular continuity.

Question 72

When comparing bone-patellar tendon-bone (BPTB) autograft to hamstring autograft for anterior cruciate ligament (ACL) reconstruction, which of the following is a recognized disadvantage of the BPTB graft?

Explanation

A primary disadvantage of the BPTB autograft is donor site morbidity, particularly anterior knee pain and pain with kneeling. BPTB offers excellent initial fixation and faster bone-to-bone healing compared to soft tissue grafts.

Question 73

A 55-year-old woman presents with advanced, neglected carpal tunnel syndrome, exhibiting severe thenar atrophy. Which specific intrinsic hand muscle is most classically atrophied and visible in this condition?

Explanation

The abductor pollicis brevis (APB) is innervated by the recurrent motor branch of the median nerve. Severe compression in the carpal tunnel leads to denervation and classic wasting of the APB, which constitutes the bulk of the superficial thenar eminence.

Question 74

A 13-year-old overweight boy presents with a limp and right groin pain for 3 weeks. On physical examination, as the right hip is passively flexed, the limb obligatorily rotates externally. What is the most likely diagnosis?

Explanation

Obligatory external rotation with passive hip flexion is the classic clinical sign of a Slipped Capital Femoral Epiphysis (SCFE). This occurs most commonly in overweight adolescents during their growth spurt.

Question 75

A 28-year-old male sustains a closed comminuted tibial shaft fracture. Twelve hours post-injury, he develops severe pain out of proportion to the injury, pain with passive stretch of his toes, and a tense calf. What is the generally accepted threshold for intracompartmental pressure relative to diastolic blood pressure (Delta P) indicating the need for an emergent fasciotomy?

Explanation

A Delta P (diastolic blood pressure minus compartment pressure) of less than 30 mmHg strongly correlates with inadequate tissue perfusion and is a standard indication for emergent four-compartment fasciotomy of the leg.

Question 76

In the process of secondary bone healing, which physiological phase is characterized by the replacement of the cartilaginous soft callus with woven bone through endochondral ossification?

Explanation

The hard callus phase of secondary fracture healing involves the mineralization of the fibrocartilaginous soft callus, converting it into woven bone. This is primarily achieved via endochondral ossification.

Question 77

During a total knee arthroplasty, the surgeon performs gap assessment and notes that the knee is tight in flexion but perfectly balanced in extension. Which of the following surgical adjustments is most appropriate to specifically increase the flexion gap?

Explanation

A tight flexion gap with an adequate extension gap requires addressing only the flexion side. Downsizing the femoral component (to decrease the posterior condylar offset) or releasing the PCL (if retaining it) effectively increases the flexion gap without altering the extension gap.

Question 78

A 15-year-old gymnast presents with lower back pain exacerbated by spinal extension. Radiographs show a bilateral defect in the pars interarticularis of L5 with a 25% anterior translation of L5 over S1. Neurological examination is normal. What is the most appropriate initial management?

Explanation

This patient has an isthmic spondylolisthesis (Grade I). Initial management in a neurologically intact adolescent with a low-grade slip is conservative, consisting of activity restriction, bracing if acute, and core stabilization exercises.

Question 79

A 35-year-old man feels a sudden "pop" in his posterior ankle while playing basketball. He has a positive Thompson test on examination. Which specific clinical finding constitutes a positive Thompson test?

Explanation

The Thompson test evaluates the integrity of the Achilles tendon. Squeezing the calf muscle in a prone patient should normally cause passive ankle plantarflexion; an absence of this movement is a positive test, indicating a complete rupture.

Question 80

Articular cartilage derives its unique resilience and capacity to resist extreme compressive forces primarily from which of the following molecular interactions?

Explanation

The compressive stiffness of articular cartilage is governed by the osmotic swelling pressure of the negatively charged glycosaminoglycans on aggrecan molecules, which strongly attract and retain water within the Type II collagen meshwork.

Question 81

Review the clinical image

. A 40-year-old male arrives in the trauma bay in hemorrhagic shock following a high-energy crush injury. The AP radiograph demonstrates an "open book" pelvic fracture with wide symphyseal diastasis. What is the most critical initial orthopaedic intervention to control hemodynamics?

Explanation

In a hemodynamically unstable patient with an open book (APC) pelvic ring injury, the application of a pelvic binder centered precisely over the greater trochanters reduces pelvic volume, promoting tamponade of venous bleeding.

Question 82

In the Ponseti method for the conservative management of idiopathic clubfoot, the sequence of deformity correction is strictly protocolized. Which of the following represents the correct order of correction?

Explanation

The Ponseti technique follows the CAVE sequence: Cavus is corrected first by elevating the first ray, followed simultaneously by Adductus and Varus correction by abducting the foot around the talar head, and finally Equinus is addressed (often requiring an Achilles tenotomy).

Question 83

A 60-year-old man presents with progressive deep pelvic pain. Radiographs reveal a large, lobulated lytic lesion in the ilium with "popcorn" stippled calcifications. Biopsy demonstrates a hyaline cartilage matrix with atypical chondrocytes. What is the mainstay of treatment for conventional low-grade chondrosarcoma of the pelvis?

Explanation

Conventional chondrosarcoma is notoriously resistant to both chemotherapy and radiation. Wide surgical excision with negative margins is the definitive treatment and offers the only chance for a cure.

Question 84

A 4-month-old infant with obstetric brachial plexus palsy presents with an internal rotation contracture of the shoulder and complete absence of active biceps function. Wrist extension is also absent. What is the most appropriate next step in management?

Explanation

The absolute absence of biceps recovery by 3 to 4 months of age in obstetric brachial plexus palsy is a widely accepted surgical indication for nerve exploration. Delaying microsurgical reconstruction beyond this period leads to significantly poorer functional motor recovery.

Question 85

A 25-year-old man suffered a C5-C6 root avulsion injury resulting in a permanent loss of elbow flexion. Hand and wrist functions remain entirely normal. A Steindler flexorplasty is planned to restore active elbow flexion. Which of the following anatomical structures is transferred during this procedure?

Explanation

The Steindler flexorplasty involves surgically transferring the flexor-pronator muscle origin from the medial epicondyle proximally to the anterior aspect of the humerus. This effectively changes their moment arm, providing active elbow flexion in patients with preserved hand and wrist musculature.

Question 86

A 40-year-old male presents with sudden, severe, unprovoked right shoulder pain lasting for 2 weeks. As the pain subsides, he notices profound weakness in shoulder abduction and external rotation. EMG demonstrates denervation potentials in the supraspinatus and infraspinatus muscles. What is the most likely diagnosis?

Explanation

Parsonage-Turner syndrome (acute brachial neuritis) classically presents with an initial phase of severe shoulder girdle pain followed by patchy muscle weakness and atrophy as the pain abates. It most commonly affects the suprascapular nerve, long thoracic nerve, or axillary nerve, and is primarily treated conservatively.

Question 87

During the clinical and electrodiagnostic evaluation of a patient with a traumatic closed brachial plexus injury, which of the following findings is most strongly indicative of a preganglionic root avulsion rather than a postganglionic lesion?

Explanation

In a preganglionic root avulsion, the injury is proximal to the dorsal root ganglion (DRG). Because the DRG remains intact and connected to the peripheral nerve, sensory axons do not undergo Wallerian degeneration, resulting in normal SNAPs despite profound clinical anesthesia.

Question 88

A 30-year-old man sustains a closed midshaft humeral fracture after a fall.

Upon initial clinical examination in the emergency department, he exhibits an inability to actively extend his wrist and metacarpophalangeal joints. Sensation is decreased over the dorsal first web space. What is the most appropriate initial management for this neurological deficit?

Explanation

The standard of care for a primary radial nerve palsy associated with a closed midshaft humeral fracture is observation and supportive dynamic splinting. The vast majority of these injuries are neuropraxias or axonotmeses that will spontaneously recover within 3 to 4 months.

Question 89

A newborn infant presents with a claw hand deformity, an absent grasp reflex, but a completely preserved Moro reflex in the upper arm and shoulder. Examination also reveals mild ptosis and miosis on the ipsilateral side. Which nerve roots of the brachial plexus are predominantly involved in this injury?

Explanation

This presentation is classic for Klumpke's palsy, which involves an injury to the lower roots of the brachial plexus (C8 and T1). The concurrent ptosis and miosis indicate an ipsilateral Horner's syndrome due to involvement of the adjacent sympathetic chain.

Question 90

A 28-year-old female overhead athlete complains of vague pain, numbness, and tingling in her medial forearm and fourth and fifth digits. Symptoms are exacerbated by overhead activities. Provocative maneuvers such as the Roos stress test and Adson's test are positive. Which anatomical structure is most frequently responsible for this specific pattern of neural compression?

Explanation

Neurogenic thoracic outlet syndrome most commonly affects the lower trunk (C8-T1) of the brachial plexus, leading to medial arm and hand symptoms. It is frequently caused by compression from a true cervical rib or an anomalous fibrous band extending from C7 in the scalene triangle.

Question 91

A 22-year-old patient with an upper trunk (C5-C6) brachial plexus injury is scheduled for an Oberlin transfer to restore elbow flexion, as his lower trunk function is fully intact. Which of the following best describes the standard surgical technique for an Oberlin transfer?

Explanation

The classic Oberlin transfer is a nerve transfer procedure that restores elbow flexion by mobilizing a redundant motor fascicle from the uninjured ulnar nerve and coapting it directly to the motor branch of the biceps muscle.

Question 92

A 32-year-old professional volleyball player presents with an insidious onset of posterior shoulder pain and progressive weakness in external rotation. Clinical examination shows isolated atrophy of the infraspinatus muscle with a completely normal supraspinatus muscle bulk and strength. Where is the most likely site of nerve compression?

Explanation

Compression of the suprascapular nerve at the spinoglenoid notch affects only the distal branch that supplies the infraspinatus, leading to isolated infraspinatus weakness. Conversely, compression at the suprascapular notch would affect both the supraspinatus and infraspinatus muscles.

Question 93

A 22-year-old male is evaluated 6 months after sustaining a massive upper extremity crush injury. He has intact shoulder abduction and elbow flexion but cannot actively extend his wrist or fingers.

EMG demonstrates absent motor units in the extensor carpi radialis brevis (ECRB) and extensor digitorum communis (EDC) with no signs of reinnervation. Tendon transfers are planned. Which of the following is the most standard and reliable tendon transfer to restore active wrist extension?

Explanation

In the setting of an irreversible radial nerve palsy, the standard tendon transfer to restore functional wrist extension utilizes the pronator teres (PT) transferred to the ECRB. The ECRB is chosen over the ECRL because its central insertion at the base of the third metacarpal prevents unwanted radial deviation.

Orthopedic Prometric Exam Preparation MCQs - Part 1

Orthopedic Prometric Exam Preparation MCQs - Part 11

Orthopedic Prometric Exam Preparation MCQs - Part 11

Chapter Index