AAOS & ABOS Shoulder Board Review MCQs (Set 4)

Question 1

A 50-year-old electrician who is right-hand dominant has had right shoulder pain and stiffness after sustaining an electric shock 2 months ago. An AP radiograph obtained at the time of injury was considered negative, and the patient was diagnosed with a shoulder sprain. The patient now reports continued shoulder pain and restricted motion. AP and axillary radiographs and a CT scan are shown in Figures 41a through 41c. Management should consist of

Explanation

Open reduction and transfer of the subscapularis and lesser tuberosity into the humeral head defect is the treatment of choice for chronic posterior dislocations in which the articular defect consists of 20% to 40% of the articular surfaces. Closed reduction can be used if the dislocation is recognized early and the articular defect is less than 20% of the articular surface. Humeral arthroplasty is reserved for patients with an articular defect that is greater than 45% to 50% of the head. Hawkins RJ, Neer CS II, Pianta RM, Mendoza FX: Locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1987;69:9-18.

Question 2

Figure 42 shows the radiograph of a 70-year-old woman who has had a painful near ankylosis of her dominant elbow for 1 year. Treatment should consist of

Explanation

The patient has arthritis and supracondylar nonunion of the elbow. Total elbow replacement has been shown to give almost immediate return of function as it can be performed while leaving the triceps intact and resecting the distal humerus fragment. Attempts at osteosynthesis are indicated in younger individuals with good joint surface. Resection arthroplasty yields poor function and is reserved as a salvage procedure. Ramsey ML, Morrey BF: Total elbow arthroplasty for nonunion and dysfunctional instability, in Morrey BF (ed): The Elbow and Its Disorders, ed 3. Philadelphia, PA, WB Saunders, 2000, pp 655-661.

Question 3

A 72-year-old woman who was doing well after undergoing total shoulder arthroplasty for arthritis 4 months ago is suddenly unable to elevate her arm. Examination reveals 70 degrees of external rotation compared with 45 degrees on the uninvolved side, and she is unable to lift her hand off her lower back. Radiographs are shown in Figures 43a through 43c. Treatment should consist of

Explanation

Results of treatment of subscapularis rupture are best when immediate repair is performed. When the cause of the anterior instability is the result of rupture of the subscapularis tendon and the component position is acceptable, revising the position of the component is unnecessary. Restoring the coracoacromial arch and subacromial decompression are related to superior instability and rotator cuff pathology, respectively, and would not correct the instability caused by subscapularis rupture. Moeckel BH, Altchek DW, Warren RF, Wickiewicz TL, Dines DM: Instability of the shoulder after arthroplasty. J Bone Joint Surg Am 1993;75:492-497.

Question 4

A 25-year-old man underwent a Putti-Platt repair for recurrent anterior dislocation of his right shoulder 9 months ago. He reports no further episodes of instability but continues to have severely restricted motion, with external rotation limited to less than 0 degrees with the arm at the side. He has pain at the ends of range of motion and restricted activities of daily living despite undergoing nearly 9 months of physical therapy. Radiographs of the shoulder show no arthritic changes. Management should now consist of

Explanation

Open release allows lengthening of the shortened subscapularis and is preferred when there are extra-articular contractures. Arthroscopic release, combined with the use of an interscalene catheter postoperatively, is an excellent treatment for capsular contractures but is contraindicated after procedures that result in extracapsular shortening (ie, Magnuson-Stack, Putti-Platt). Additional physical therapy or manipulation under anesthesia is not likely to be helpful. Shoulder hemiarthroplasty is contraindicated with normal articular surfaces, but prosthetic arthroplasty is sometimes necessary for arthritis associated with instability or overly tight instability repairs. Harryman DT II, Matsen FA III, Sidles JA: Arthroscopic management of refractory shoulder stiffness. Arthroscopy 1997;13:133-147. Warner JJ: Frozen shoulder: Diagnosis and management. J Am Acad Orthop Surg 1997;5:130-140. Warner JJ, Allen AA, Marks PH, Wong P: Arthroscopic release of postoperative capsular contracture of the shoulder. J Bone Joint Surg Am 1997;79:1151-1158.

Question 5

A 43-year-old bus driver sustains a hyperextension injury to her arm and shoulder 4 months after undergoing an open Bankart repair. Examination reveals increased external rotation, anterior shoulder pain, and internal rotation weakness. Her examination also reveals the findings shown in Figure 44. What is the most likely diagnosis?

Explanation

An isolated tear of the subscapularis tendon has been noted as early as 1835 by Smith. In Gerber and associates' 1991 report of 16 men with an average age of 51 years, isolated subscapularis tendon rupture was often caused by a violent hyperextension injury. All patients reported pain anteriorly along with night pain. They also noted pain and weakness of the arm. The lift-off test is performed by having the patient lift the palm of the hand away from the small of the back. The patient must have sufficient internal rotation to allow this test to be performed. A subscapularis rupture is likely if the patient cannot perform the lift-off test. Hertel R, Ballmer FT, Lombert SM, Gerber C: Lag signs in the diagnosis of rotator cuff rupture. J Shoulder Elbow Surg 1996;5:307-313. Gerber C, Krushell RJ: Isolated rupture of the tendon of the subscapularis muscle: Clinical features in 16 cases. J Bone Joint Surg Br 1991;73:389-394. Greis PE, Kuhn JE, Schultheis J, Hintermeister R, Hawkins R: Validation of the lift-off test and analysis of subscapularis activity during maximal internal rotation. Am J Sports Med 1996;24:589-593.

Question 6

Radial nerve palsy is most commonly associated with which of the following types of humeral fractures?

Explanation

Although the Holstein-Lewis fracture, described as an oblique distal one third fracture, is best known for its association with neurologic injury, radial nerve palsy is most commonly associated with middle one third humeral fractures. Most nerve injuries are neurapraxias or axonotmeses, with up to 90% resolving in 3 to 4 months. Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 271-286.

Question 7

A 30-year-old firefighter sustained a longitudinal pulling injury to the arm while attempting to move a heavy object during a fire. Figure 45 shows an MRI scan of the elbow. Initial management should consist of

Explanation

Because the MRI scan shows a complete rupture of the distal biceps tendon, the preferred treatment is anatomic repair of the tendon to the radial tuberosity either with the use of suture anchors or transosseous sutures through a two-incision technique. Several studies have documented superior results with anatomic repair of the distal biceps tendon when compared with results of nonsurgical management or repair of the tendon by attachment to the brachialis muscle. Patients undergoing anatomic repair of the distal biceps tendon through a two-incision technique typically regain a functional range of motion and nearly normal strength. D'Alessandro DF, Shields CL Jr, Tibone JE, Chandler RW: Repair of distal biceps tendon ruptures in athletes. Am J Sports Med 1993;21:114-119. Boyd JB, Anderson LD: A method for reinsertion of the distal biceps brachii tendon. J Bone Joint Surg Am 1961;43:1041-1043. Morrey BF, Askew LJ, An KN, Dobyns JH: Rupture of the distal tendon of the biceps brachii: A biomechanical study. J Bone Joint Surg Am 1985;67:418-421.

Question 8

Which of the following is considered a reasonable goal for arthroplasty surgery in rotator cuff arthropathy?

Explanation

Absence of the rotator cuff results in superior migration of the humeral head because of unopposed deltoid function. This proximal migration results in eccentric loading of glenoid components with early loosening. Hemiarthroplasty yields good pain relief with limited goals of active elevation of 90 degrees. The coracoacromial arch should be preserved. Achieving satisfactory subscapularis tension is preferred to the use of an oversized humeral component. Zeman CA, Arcand MA, Cantrell JS, Skedros JG, Burkhead WZ Jr: The rotator cuff-deficient arthritic shoulder: Diagnosis and surgical management. J Am Acad Orthop Surg 1998;6:337-348. Arntz CT, Jackins S, Matsen FA III: Prosthetic replacement of the shoulder for the treatment of defects in the rotator cuff and the surface of the glenohumeral joint. J Bone Joint Surg Am 1993;75:485-491. Williams GR Jr, Rockwood CA Jr: Hemiarthroplasty in rotator cuff-deficient shoulders. J Shoulder Elbow Surg 1996;5:362-367.

Question 9

What is the best surgical approach for the scapular fracture shown in Figure 46?

Explanation

Indications for open reduction of glenoid intra-articular fractures include those fractures with a 5-mm articular surface displacement or when the humeral head is subluxated with the fracture fragment. Kavanaugh and associates and Leung and Lam have shown that the posterior approach with plate fixation is best for most glenoid fractures, including the Ideberg type II fracture shown here. The anterior approach is best used for anterior rim and transverse fractures. Kavanagh BF, Bradway JK, Cofield RH: Open reduction and internal fixation of displaced intra-articular fractures of the glenoid fossa. J Bone Joint Surg Am 1993;75:479-484. Leung KS, Lam TP: Open reduction and internal fixation of ipsilateral fractures of the scapular neck and clavicle. J Bone Joint Surg Am 1993;75:1015-1018.

Question 10

Management of a grade IV osteochondritis dissecans lesion of the capitellum should consist of

Explanation

Osteochondritis dissecans of the capitellum is seen most commonly in adolescent athletes. It should be distinguished from osteochondrosis of the capitellum (Panner's disease), a self-limiting condition seen in younger patients. Lesions are graded I through V based on radiographic and arthroscopic appearance. Grade I lesions show intact but soft cartilage. Grade II lesions show fissuring of the overlying cartilage. Grade III lesions show exposed bone or an attached osteoarticular flap that is not loose. Grade IV lesions show a loose but nondisplaced osteoarticular flap. Grade V lesions show a displaced fragment. Simple excision of the loose osteoarticular flap is the treatment of choice for grade IV and V lesions. More complex procedures such as drilling of the in situ lesion, bone grafting, or internal fixation are associated with significantly worse results. While some authors advocate abrasion chondroplasty, the long-term benefits of the procedure are yet to be proven. Baumgarten TE: Osteochondritis dissecans of the capitellum. Sports Med Arthroscopy Rev 1995;3:219-223.

Question 11

What preoperative factor correlates best with the outcome of rotator cuff repair?

Explanation

The size of the rotator cuff tear in both anteroposterior and mediolateral dimensions has been found to correlate best with outcome. Older patient age and rupture of the long head of the biceps tend to be associated with larger tears and, therefore, may be associated indirectly with a poorer outcome. Iannotti JP: Full-thickness rotator cuff tears: Factors affecting surgical outcome. J Am Acad Orthop Surg 1994;2:87-95.

Question 12

A 55-year-old woman with polyarticular rheumatoid arthritis has had progressively increasing left shoulder pain for the past 2 years despite nonsurgical management. No focal weakness is noted during examination of the shoulder. AP and axillary radiographs are shown in Figures 47a and 47b. Treatment should consist of

Explanation

Unconstrained total shoulder arthroplasty has been found to yield satisfactory results in a high percentage of patients with rheumatoid involvement of the glenohumeral joint. Pain relief has been more predictable with total shoulder arthroplasty than humeral arthroplasty, and a glenoid component is favored when there is sufficient glenoid bone stock and an intact rotator cuff. Constrained or fixed-fulcrum devices have an unacceptably high failure rate because of loosening. Glenohumeral arthrodesis is avoided when the deltoid or rotator cuff is functioning because the functional results after arthroplasty are superior when compared with results of arthrodesis. Arthroscopic synovectomy may be helpful in early stages of the disease before extensive cartilage damage has occurred. Boyd AD Jr, Thomas WH, Scott RD, Sledge CB, Thornhill TS: Total shoulder arthroplasty versus hemiarthroplasty: Indications for glenoid resurfacing. J Arthroplasty 1990;5:329-336.

Question 13

When elevating the arm, the ratio of scapulothoracic to glenohumeral motion over the total range of motion is best described as

Explanation

The ratio of scapulothoracic to glenohumeral motion with elevation has been shown to vary depending on what portion of elevation is examined, how much load is on the arm, and the technique used to measure increments of elevation. However, almost every study shows that the ratio of scapulothoracic to glenohumeral motion is 1:2 for the contributions over a full range of elevation to 170 degrees. In the first 30 degrees of elevation, there is significant variability in the ratio, and there may be significant variability up to around 60 degrees. Inman VT, Saunders JR, Abbott LC: Observations of the function of the shoulder joint. Clin Orthop 1996;330:3-12.

Question 14

Figure 48 shows the initial AP chest radiograph of a 21-year-old motorcycle rider who sustained multiple injuries after striking a telephone pole at high speed. What is the most significant radiographic finding leading to a diagnosis?

Explanation

Scapulothoracic dissociation is a rare, violent traumatic injury in which the scapula is torn away from the chest wall but the skin remains intact. Massive swelling and ecchymosis are common. Neurovascular injury is the rule with possible subclavian or axillary artery disruption and severe partial or complete brachial plexus paralysis. The diagnosis is made on a nonrotated chest radiograph that shows significant lateral displacement of the medial scapular border from the sternal notch. A right midshaft clavicular fracture is present but is not considered the most significant finding. Ebraheim NA, An HS, Jackson WT, et al: Scapulothoracic dissociation. J Bone Joint Surg Am 1988;70:428-432. Ebraheim NA, Pearlstein SR, Savolaine ER, et al: Scapulothoracic dissociation. J Orthop Trauma 1987;1:18-23. Sampson LN, Britton JC, Eldrup-Jorgensen J, et al: The neurovascular outcome of scapulothoracic dissociation. J Vasc Surg 1993;17:1083-1088.

Question 15

A 21-year-old man who underwent repair of a distal biceps tendon rupture using a two-incision approach 4 months ago now reports difficulty gaining rotation of his forearm. Figures 49a and 49b show the AP and lateral radiographs. What is the most likely cause of his problem?

Explanation

The radiographs show early ectopic bone formation originating between the ulna and the radius. The development of ectopic bone in this area following a two-incision approach for anatomic repair of the distal biceps tendon is thought to be related to exposure of the periosteum of the lateral ulna during surgery. This can be avoided by the use of a muscle-splitting incision between the extensor carpi ulnaris and common extensor muscles. Full pronation of the forearm allows for the necessary exposure of the radial tuberosity during the procedure and for fixation of the tendon at its maximal length. Morrey BF: Tendon injuries about the elbow, in Morrey BF (ed): The Elbow and Its Disorders, ed. 2. Philadelphia, PA, WB Saunders, 1993, pp 492-503.

Question 16

A 53-year-old man reports acute, severe left shoulder pain after undergoing abdominal surgery 10 days ago. Initial management, consisting of anti-inflammatory drugs, physical therapy, and a subacromial injection of corticosteroid, fails to provide relief. Reexamination of the shoulder 2 months after the onset of symptoms reveals atrophy of the infraspinous and supraspinous fossa and profound weakness of active abduction and external rotation. His neck is supple with a full range of motion. Plain radiographs and an MRI scan of the shoulder are normal. What diagnostic study should be performed next in the evaluation of this patient?

Explanation

Suprascapular nerve palsy is a fairly uncommon yet well-known cause of shoulder pain and weakness. A variety of causes have been described, including compression by a ganglion cyst, an anomalous or thickened superior transverse scapular ligament, a humeral and scapular fracture, and traction or kinking of the nerve in the suprascapular notch. In this patient, the injury is most likely caused by traction or compression of the nerve in the suprascapular notch as the result of positioning during abdominal surgery; therefore, the studies of choice are electromyography and nerve conduction velocity studies. While MRI of the cervical spine may be of some value in ruling out a radiculopathy, the clinical history does not support such a cause for this condition. Rengachary SS, Neff JP, Singer PA, Brackett CE: Suprascapular entrapment neuropathy: A clinical, anatomical, and comparative study. Part 1: Clinical study. Neurosurgery 1979;5:441-446. Rengachary SS, Burr D, Lucas S, Hassanein KM, Mohn MP, Matzke H: Suprascapular entrapment neuropathy: A clinical, anatomical and comparative study. Part 2: Anatomical study. Neurosurgery 1979;5:447-451.

Question 17

A 58-year-old reports pain and stiffness in his left shoulder following a seizure episode. Diagnosis at the time of the seizure is a frozen shoulder, and management consists of an aggressive physical therapy program of stretching exercises. Four months later he continues to have shoulder pain and has not gained any additional range of motion. A CT scan is shown in Figure 50. Management should now consist of

Explanation

Humeral arthroplasty is indicated for chronic posterior dislocations when the impression defect in the humeral head is greater than 45% to 50%. If the condition remains undiagnosed for more than 9 to 12 months, secondary degenerative changes on the glenoid may occur, necessitating total shoulder arthroplasty. Open reduction and transfer of the subscapularis and lesser tuberosity are used for impression defects that consist of 20% to 40% of the humeral articular surface. Closed reduction and immobilization with the arm in slight extension and external rotation is useful when the posterior dislocation is diagnosed within the first 6 weeks and the articular defect is less than 20%. Hawkins RJ, Neer CS II, Pianta RM, Mendoza FX: Locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1987;69:9-18.

Question 18

When conducted at near physiologic strain rates, tensile studies of the inferior glenohumeral ligament (IGHL) have shown that the

Explanation

Tensile testing of the inferior glenohumeral ligament at near physiologic strain rates has shown that the anterior band of the IGHL has the greatest stiffness of the three ligament regions and the glenoid insertion site shows greater strain than the ligament midsubstance. Bigliani LU, Pollock RG, Soslowsky LJ, Flatow EL, Pawluk RJ, Mow VC: Tensile properties of the inferior glenohumeral ligament. J Orthop Res 1992;10:187-197.

Question 19

Manipulation under anesthesia for resistant frozen shoulder should be avoided in patients with

Explanation

Severe osteoporosis is a contraindication to manipulation under anesthesia in patients with a resistant frozen shoulder because of the higher risk of humeral fracture. Manipulation is considered for frozen shoulder in patients who are symptomatic despite undergoing a reasonable course of appropriate physical therapy. Harryman DT II: Shoulder: Frozen and stiff. Instr Course Lect 1997;42:247-257.

Question 20

A patient who sustained a cerebrovascular accident (CVA) 18 months ago has a long-standing spastic adduction contracture of the shoulder with a rigid block to passive external rotation. Significant hygiene problems exist with maceration and continued skin breakdown. Management should consist of

Explanation

Following a CVA, the muscular imbalance often leads to a fixed contracture of the shoulder in adduction, internal rotation, and flexion. The responsible muscles include the pectoralis major, subscapularis, teres major, and latissimus dorsi. If stretching cannot produce enough improvement for axillary hygiene, then surgery is an option. If the shoulder resists external rotation during examination with the arm at the side, as in this patient, then the subscapularis is spastic and contributing to the deformity as well and needs to be released along with the pectoralis. Phenol nerve blocks are most effective and best given within 6 months of the initial CVA to be effective. Lidocaine blocks may be helpful in determining whether a deformity is caused by a fixed soft-tissue contracture or by spasticity but play no role once the contracture is present. The modified L'Episcopo procedure is indicated in patients with contracture secondary to brachial plexus birth palsies. Braun RM, Botte MJ: Treatment of shoulder deformity in acquired spasticity. Clin Orthop 1999;368:54-65.

Question 21

A patient with degenerative osteoarthritis of the sternoclavicular (SC) joint reports constant pain, discomfort, and marked prominence and instability of the SC joint following medial clavicle resection. Which of the following procedures is most likely to produce these signs and symptoms?

Explanation

Medial clavicle excision alone can be associated with postoperative instability of the clavicle. The clavicle should be stabilized to the first rib by reconstructing the costoclavicular ligament if it is torn or if the resection is lateral to its clavicular insertion. Therefore, care must be taken to resect only that part of the clavicle that is medial to the costoclavicular ligament. Adequate protection for vital structures that lie posterior to the medial end of the clavicle must be provided. Bremner RA: Nonarticular noninfected subacute arthritis of the sternoclavicular joint. J Bone Joint Surg Br 1959;41:749-753.

Question 22

A 26-year-old man has had a 2-year history of pain and stiffness after sustaining a comminuted olecranon fracture. Treatment at the time of injury consisted of open reduction and internal fixation with tension band wiring. Examination reveals motion of 45 degrees to 110 degrees and pain throughout the arc of motion. Resisted flexion and extension are painful. Forearm rotation is normal. Radiographs are shown in Figure 51. Treatment should consist of

Explanation

The patient has posttraumatic arthritis of the elbow; therefore, the treatment of choice is hardware removal and soft-tissue releases with splinting to avoid recurrence of contractures. The combination of pain and stiffness in an elbow that has sustained significant joint surface damage renders it unresponsive to simple soft-tissue releases and heterotopic bone excision. Joint distraction and interposition arthroplasty offer the possibility of maintaining motion and relieving pain as a later salvage procedure. Joint replacement should not be performed in young, active, strong individuals because the prosthesis will fail quickly and complications will develop. Synovectomy and radial head excision are not indicated. Morrey BF: Distraction arthroplasty: Clinical applications. Clin Orthop 1993;293:46-54.

Question 23

What is the most common cause of rotator cuff injury in high school athletes?

Explanation

A large number of etiologies of rotator cuff injury have been proposed. Both intrinsic and extrinsic mechanisms have been suggested. In the young athlete the common underlying mechanism is overuse. Contributing factors include increased laxity, anatomic variation in the coracoacromial arch, and altered kinematics. Wilkins KE: Shoulder injuries: Epidemiology, in Stanitski CL, DeLee JC, Drez D Jr (eds): Pediatric and Adolescent Sports Medicine. Philadelphia, PA, WB Saunders, 1994, pp 175-182.

Question 24

A 16-year-old boy with osteochondritis dissecans of the capitellum has intermittent symptoms of catching and locking. Examination is unremarkable. Radiographs reveal a loose body anteriorly with a diameter of 10 mm. To remove the loose body, elbow arthroscopy is being considered. Which of the following procedures would minimize the risk of neurovascular complication during the procedure?

Explanation

Complications of elbow arthroscopy are usually minor or temporary. However, serious complications include nerve injuries. The deep radial nerve is the closest to any of the portals, resting as close as 1 mm away from the scope inserted in the anterolateral portal. The capsule can be displaced anteriorly by distending the joint with about 25 mL of saline solution, thus moving the deep radial nerve approximately 1 cm anteriorly and decreasing the risk of injuring it while establishing the anterolateral portal. Keeping plastic cannulae in the portals may help to diminish fluid extravasation and swelling, which is more of an impediment than a serious complication. The image intensifier has no documented role in guiding loose body removal. While the proximal anteromedial portal is probably the safest anterior portal to establish, it is actually easier to remove a large loose body from this portal while viewing it from an anterolateral position. There is less tendon and muscle bulk to pass through at the site of the proximal anteromedial portal than at the anterolateral portal, making it less likely for the loose body to get stuck in the soft tissues. Techniques have been developed to permit removal of loose bodies as large as 2 cm in diameter without breaking them up into pieces. If it is possible to remove a large loose body intact, doing so greatly simplifies and shortens the procedure. Lynch GJ, Meyers JF, Whipple TL, Caspari RB: Neurovascular anatomy and elbow arthroscopy: Inherent risks. Arthroscopy 1986;2:190-197.

Question 25

Examination of the shoulder seen in Figure 52 shows atrophy and tenderness of the infraspinous fossa and profound weakness in external rotation. The supraspinous fossa shows normal muscle bulk. What is the most likely cause of this condition?

Explanation

Compression of the suprascapular nerve by a ganglion cyst is a well-documented cause of pain and weakness in the shoulder. Isolated involvement of the infraspinatus indicates that the area of entrapment is at the spinoglenoid notch and not the suprascapular notch. The majority of ganglion cysts found in the shoulder are related to tears of the labrum. When such a compressive lesion is found, decompression can be accomplished through either an open or arthroscopic approach. Several authors have shown the value of arthroscopy in the treatment of this condition. It has been shown that it is technically possible to decompress a paralabral ganglion cyst using arthroscopy; this method is usually followed by repair of the torn labrum. Alternatively, arthroscopic repair of the labrum can be performed and the cyst may be aspirated at the time of surgery. Open cyst excision through a posterior approach is also an acceptable method of treatment. Schickendantz MS, Ho CP: Suprascapular nerve compression by a ganglion cyst: Diagnosis by magnetic resonance imaging. J Shoulder Elbow Surg 1993;2:110-114. Thompson RC, Schneider W, Kennedy T: Entrapment neuropathy of the inferior branch of the suprascapular nerve by ganglia. Clin Orthop 1982;166:185-187.

Question 26

A 76-year-old woman presents with severe right shoulder pain and an inability to actively elevate her arm above 60 degrees. Passive elevation is preserved to 150 degrees. Radiographs demonstrate a superiorly migrated humeral head with articulation against the acromion and severe glenohumeral osteoarthritis. What is the most appropriate definitive surgical management?

Explanation

This patient has rotator cuff tear arthropathy with pseudoparalysis. Reverse total shoulder arthroplasty is the treatment of choice, as it relies on the deltoid rather than the deficient rotator cuff to restore forward elevation.

Question 27

A 28-year-old professional volleyball player presents with insidious onset of posterior shoulder pain and weakness. Examination reveals isolated weakness in external rotation with the arm at the side. MRI demonstrates a paralabral cyst at the spinoglenoid notch. Which muscle is most likely to show denervation changes on EMG?

Explanation

Compression of the suprascapular nerve at the spinoglenoid notch affects only the infraspinatus muscle. Compression more proximally at the suprascapular notch would affect both the supraspinatus and infraspinatus.

Question 28

A 68-year-old man underwent an anatomic total shoulder arthroplasty via a deltopectoral approach 6 weeks ago. He now complains of new-onset weakness and a sensation of anterior instability. On examination, he has increased passive external rotation compared to the contralateral side and a positive belly-press test. Failure of which of the following structures is most likely responsible?

Explanation

The subscapularis is taken down and repaired during a standard deltopectoral approach for TSA. Postoperative failure presents with increased passive external rotation and weakness in internal rotation tests (belly-press, lift-off).

Question 29

A 21-year-old male contact athlete presents with recurrent anterior shoulder instability. CT scan with 3D reconstruction reveals 28% anterior glenoid bone loss. Which of the following is the most appropriate surgical intervention?

Explanation

In the setting of recurrent anterior instability with critical glenoid bone loss (typically >20-25%), an isolated soft tissue repair has an unacceptably high failure rate. The Latarjet procedure (coracoid transfer) is indicated to restore the glenoid arc and provide a sling effect.

Question 30

A 45-year-old man presents to the ER after a generalized tonic-clonic seizure. He complains of right shoulder pain and is unable to externally rotate the arm past neutral. An axillary radiograph confirms a posterior shoulder dislocation with an impaction fracture of the anteromedial humeral head involving 35% of the articular surface. What is the most appropriate surgical treatment?

Explanation

For locked posterior dislocations with a reverse Hill-Sachs defect involving 25% to 40% of the articular surface, filling the defect is necessary to prevent recurrent instability. The modified McLaughlin procedure transfers the lesser tuberosity and subscapularis into the defect.

Question 31

An MRI of a 24-year-old male with recurrent shoulder instability demonstrates a 'J-sign' with extravasation of contrast into the axillary pouch. There is no labral tear identified on the glenoid rim. This finding is most consistent with which of the following injuries?

Explanation

A HAGL lesion represents an avulsion of the inferior glenohumeral ligament from its humeral attachment. On MRI arthrogram, this disrupts the normal U-shape of the axillary pouch, creating a classic 'J-sign' as contrast leaks inferiorly.

Question 32

According to recent anatomic studies, which of the following arteries provides the dominant blood supply to the humeral head?

Explanation

Historically, the anterior circumflex humeral artery (arcuate branch) was thought to be dominant. However, recent quantitative perfusion studies have proven that the posterior circumflex humeral artery provides the majority of the blood supply to the humeral head.

Question 33

A 65-year-old woman sustains a 3-part proximal humerus fracture. It is treated with open reduction and internal fixation using a locking plate. During follow-up, she complains of new, progressive shoulder pain and mechanical catching. Radiographs show varus collapse of the fracture. What is the most common hardware-related complication associated with this failure pattern?

Explanation

Varus collapse of a proximal humerus fracture treated with a locking plate frequently leads to relative intra-articular screw penetration (cutout). Placement of calcar screws during initial surgery is critical to support the inferomedial neck and prevent this varus collapse.

Question 34

The dynamic stability of the glenohumeral joint is maintained by muscular force couples. Which of the following muscle pairings constitutes the primary transverse plane force couple of the shoulder?

Explanation

The subscapularis (anterior) and the infraspinatus/teres minor (posterior) form the transverse plane force couple. They work in concert to compress the humeral head into the glenoid during active motion, maintaining concentric reduction.

Question 35

A 55-year-old man presents with chronic shoulder pain. An MRI reveals a massive, irreparable tear of the supraspinatus and infraspinatus tendons with grade 4 fatty infiltration. The subscapularis and teres minor are intact. The patient has preserved forward elevation but profound weakness in external rotation (positive Hornblower's sign). Which of the following tendon transfers is most appropriate to restore external rotation?

Explanation

Latissimus dorsi or lower trapezius tendon transfers are indicated for massive, irreparable posterosuperior rotator cuff tears (supraspinatus/infraspinatus) to restore active external rotation and improve forward elevation in patients without significant arthritis.

Question 36

A 16-year-old female gymnast presents with bilateral shoulder pain. She describes a sensation of her shoulders 'slipping out of place' during routine activities. Examination reveals a positive sulcus sign, generalized ligamentous laxity, and symmetric multidirectional instability. What is the most appropriate initial management?

Explanation

The initial treatment for multidirectional instability (MDI) is a prolonged trial of physical therapy (typically 6 months) focusing on strengthening the rotator cuff and periscapular stabilizers. Operative management is reserved for refractory cases.

Question 37

A 60-year-old man sustains an anterior shoulder dislocation. After closed reduction, he is noted to have isolated numbness over the lateral aspect of the shoulder and profound weakness in shoulder abduction. Which of the following muscles, in addition to the deltoid, is primarily denervated by this nerve injury?

Explanation

The axillary nerve is the most commonly injured nerve during anterior shoulder dislocations. It innervates the deltoid and the teres minor muscles, and provides sensation to the lateral shoulder (superior lateral cutaneous nerve of the arm).

Question 38

A 40-year-old construction worker has an MRI of the shoulder demonstrating an articular-sided partial-thickness tear of the supraspinatus tendon involving 60% of the tendon footprint (PASTA lesion). He has failed 6 months of conservative treatment. What is the standard surgical management for this lesion?

Explanation

Partial articular-sided supraspinatus tendon avulsion (PASTA) lesions involving greater than 50% of the tendon footprint are generally treated with surgical repair. This can be done via completing the tear and performing a standard repair, or an in situ transtendon repair.

Question 39

A 26-year-old patient undergoes an arthroscopic anterior stabilization. During diagnostic arthroscopy, the anterior labrum is found to be avulsed from the glenoid rim and displaced medially, having healed to the medial scapular neck along with the intact underlying periosteum. Which of the following eponymous terms describes this lesion?

Explanation

An Anterior Labroligamentous Periosteal Sleeve Avulsion (ALPSA) lesion is characterized by the medial displacement of the labrocapsular complex along the scapular neck with an intact periosteal sleeve. It must be mobilized and shifted laterally during repair.

Question 40

A 58-year-old woman sustains a severely displaced 4-part proximal humerus fracture. The humeral head is noted to be entirely devascularized on advanced imaging. When comparing hemiarthroplasty to reverse total shoulder arthroplasty (RTSA) for this patient, RTSA has been shown in the literature to provide which of the following advantages?

Explanation

In elderly patients with 4-part proximal humerus fractures, RTSA provides more predictable active forward elevation and better functional outcomes compared to hemiarthroplasty, primarily because RTSA outcomes are less reliant on the anatomic healing of the tuberosities.

Question 41

A 22-year-old male sustains a recurrent anterior shoulder dislocation. MRI reveals a 10% anterior glenoid bone loss and a deep, engaging Hill-Sachs lesion. Which of the following procedures is indicated to directly address the humeral head defect and prevent it from engaging the anterior glenoid rim?

Explanation

The Remplissage procedure involves capsulotenodesis of the infraspinatus into the Hill-Sachs defect. It is indicated for engaging Hill-Sachs lesions with subcritical (<20%) glenoid bone loss, converting an intra-articular defect to an extra-articular one.

Question 42

A 68-year-old female presents with a 4-part proximal humerus fracture. Radiographs demonstrate a valgus-impacted fracture pattern. Which of the following features makes this specific fracture pattern more amenable to joint-preserving fixation compared to a classic displaced 4-part fracture?

Explanation

Valgus-impacted 4-part proximal humerus fractures have a significantly lower rate of avascular necrosis than displaced 4-part fractures because the medial periosteal hinge remains intact, preserving the critical blood supply from the posterior circumflex humeral artery.

Question 43

A 45-year-old man presents with chronic anterior shoulder pain and positive lift-off and belly-press tests. MRI demonstrates a chronic, massive, irreparable tear of the subscapularis tendon. The supraspinatus and infraspinatus are completely intact. Which tendon transfer is most commonly recommended to address this specific deficit?

Explanation

A pectoralis major tendon transfer is the procedure of choice for an isolated, irreparable subscapularis tendon tear. It provides an anterior dynamic force vector that substitutes for the deficient subscapularis to restore internal rotation and transverse plane balance.

Question 44

A 32-year-old male is evaluated for chronic shoulder pain. On clinical examination, you suspect a SLAP tear. Which of the following provocative tests is characterized by the patient reporting deep shoulder pain when the arm is forward elevated to 90 degrees, adducted 10 degrees, and internally rotated against resistance, which then improves with external rotation?

Explanation

O'Brien's active compression test is considered positive for labral pathology if pain is elicited with the arm in internal rotation (thumb down) and relieved when the arm is in external rotation (palm up).

Question 45

In evaluating a patient with suspected acromioclavicular (AC) joint arthritis versus superior labral pathology, the cross-body adduction test is performed. If the AC joint is the primary pain generator, where is the pain most predictably localized during this maneuver?

Explanation

The cross-body adduction test compresses the acromioclavicular joint. Pain localized specifically to the top of the shoulder over the AC joint indicates AC joint pathology, whereas deep glenohumeral pain may suggest labral or capsular issues.

Question 46

A 24-year-old rugby player presents with recurrent anterior shoulder instability following a primary dislocation 2 years ago. Advanced imaging demonstrates a 26% anterior glenoid bone loss and an engaging Hill-Sachs lesion. What is the most appropriate definitive surgical management?

Explanation

Glenoid bone loss exceeding 20-25% in a collision athlete is a strict indication for bony augmentation, most commonly the Latarjet procedure. Soft tissue repairs alone carry an unacceptably high failure rate in the setting of critical bone loss.

Question 47

A 72-year-old man presents with chronic shoulder pain and an inability to actively elevate his arm beyond 40 degrees. Radiographs demonstrate superior migration of the humeral head articulating with the acromion and acetabularization of the coracoacromial arch. The patient is diagnosed with rotator cuff tear arthropathy. What is the most appropriate surgical treatment?

Explanation

Reverse total shoulder arthroplasty is the gold standard treatment for rotator cuff tear arthropathy with pseudoparalysis. It medializes and distalizes the center of rotation to optimize the deltoid lever arm, restoring active elevation.

Question 48

A 65-year-old woman sustains a 3-part proximal humerus fracture involving the surgical neck and greater tuberosity. The tuberosity fragment is displaced 1.5 cm superiorly. Which muscle group is the primary deforming force responsible for this superior displacement?

Explanation

The supraspinatus pulls the fractured greater tuberosity superiorly, while the infraspinatus and teres minor pull it posteriorly. The pectoralis major is the primary deforming force displacing the humeral shaft medially.

Question 49

A 38-year-old man presents with severe left shoulder pain and the arm locked in internal rotation after experiencing a generalized tonic-clonic seizure. An AP radiograph demonstrates a symmetric "lightbulb" appearance of the humeral head. What is the expected associated humeral head bone defect?

Explanation

Seizures or electrical shocks classically cause posterior shoulder dislocations, locked in internal rotation. This frequently results in an impaction fracture on the anteromedial humeral head, known as a reverse Hill-Sachs lesion.

Question 50

During open reduction and internal fixation of a proximal humerus fracture via an extended deltopectoral approach, which nerve is at greatest risk of iatrogenic injury when placing retractors beneath the deltoid or splitting its distal fibers?

Explanation

The axillary nerve courses anterior to posterior on the deep surface of the deltoid, approximately 5 to 7 cm distal to the lateral edge of the acromion. It is highly susceptible to traction or transection during distal deltoid mobilization.

Question 51

A 55-year-old man exhibits increased external rotation and weakness with internal rotation after a fall on an outstretched hand. Clinical examination reveals positive belly-press and lift-off tests. Which associated long head of the biceps (LHB) pathology is most commonly observed during arthroscopy in this setting?

Explanation

The subscapularis tendon insertion forms the medial boundary of the bicipital groove. A full-thickness subscapularis tear often disrupts the medial sling (transverse humeral ligament/coracohumeral ligament), leading to medial subluxation or dislocation of the LHB tendon.

Question 52

A 28-year-old professional volleyball player presents with insidious onset of vague posterolateral shoulder pain and isolated, visible atrophy of the infraspinatus fossa. MRI reveals a large paralabral cyst. Where is the most likely anatomic location of the nerve compression?

Explanation

Compression of the suprascapular nerve at the spinoglenoid notch, often by a paralabral cyst secondary to a posterior labral tear, results in isolated infraspinatus weakness and atrophy. Compression at the suprascapular notch would affect both the supraspinatus and infraspinatus.

Question 53

A 65-year-old patient suffers an anterior shoulder dislocation. After successful closed reduction, the patient demonstrates profound weakness in abduction and external rotation. Electromyography confirms axillary nerve neurapraxia. Which additional injury typically completes the "terrible triad of the shoulder" in this age group?

Explanation

The "terrible triad of the shoulder" in older patients is defined as an anterior shoulder dislocation, an axillary nerve injury, and a concurrent rotator cuff tear. Early identification of the cuff tear is critical for restoring function.

Question 54

A patient is evaluated 2 years after receiving a reverse total shoulder arthroplasty (RTSA). Radiographs reveal a progressive lucency and bone loss on the inferior scapular neck. What is the primary mechanical cause of this scapular notching?

Explanation

Scapular notching after RTSA is primarily caused by mechanical impingement of the medial humeral metaphysis or polyethylene liner against the inferior scapular neck during adduction. Inferior baseplate positioning and lateralization can help minimize this risk.

Question 55

A 50-year-old woman with poorly controlled type 1 diabetes mellitus presents with a 5-month history of insidious, severe, diffuse shoulder pain and progressive loss of both active and passive range of motion. Examination shows symmetric restriction in all planes. Which clinical phase of adhesive capsulitis is she currently in?

Explanation

Adhesive capsulitis progresses through three main stages. The "freezing" phase (typically lasting 2-9 months) is characterized by severe, progressive pain and stiffness. The subsequent "frozen" phase is marked by profound stiffness but gradually subsiding pain.

Question 56

During hemiarthroplasty for a complex 4-part proximal humerus fracture, restoring precise humeral length is critical for soft-tissue balancing. The surgeon should measure the distance from the superior margin of the pectoralis major tendon insertion to the top of the prosthetic humeral head. This distance should be approximately:

Explanation

The superior border of the pectoralis major tendon is a reliable landmark. The average distance from this border to the superior aspect of the articular surface of the humeral head is approximately 5.6 cm. Restoring this height prevents overstuffing or profound weakness.

Question 57

A 65-year-old woman sustains a 4-part proximal humerus fracture. Which of the following radiographic findings is the most reliable predictor of subsequent humeral head ischemia?

Explanation

According to Hertel's criteria, the most reliable predictors of humeral head ischemia are a metaphyseal head extension (calcar length) of less than 8 mm and disruption of the medial periosteal hinge. These findings indicate significant disruption of the blood supply to the humeral head.

Question 58

A 22-year-old man undergoes a Latarjet procedure for recurrent anterior instability with 25% glenoid bone loss. Postoperatively, he exhibits weakness in elbow flexion and numbness over the lateral aspect of the forearm. Which nerve was most likely injured during the procedure?

Explanation

The musculocutaneous nerve is at high risk during the Latarjet procedure, particularly during aggressive medial retraction of the conjoint tendon. Injury results in weakness of the biceps and brachialis, as well as sensory deficits in the distribution of the lateral antebrachial cutaneous nerve.

Question 59

A 70-year-old man presents with an irreparable massive rotator cuff tear. He demonstrates pseudoparalysis with active forward elevation limited to 40 degrees, but his passive range of motion is fully preserved. His deltoid function is intact. What is the most appropriate surgical treatment?

Explanation

Reverse total shoulder arthroplasty relies on a functioning deltoid to restore active elevation in patients with a deficient rotator cuff. It is the treatment of choice for elderly patients with massive, irreparable rotator cuff tears and pseudoparalysis with preserved passive motion.

Question 60

During shoulder arthroscopy for recurrent anterior instability, the surgeon notes a detached anterior labrum that is displaced medially and inferiorly along the glenoid neck. The anterior scapular periosteum remains intact. What is the correct term for this lesion?

Explanation

An Anterior Labroligamentous Periosteal Sleeve Avulsion (ALPSA) lesion is characterized by a medially and inferiorly displaced labrum with an intact anterior scapular periosteum. Unlike a Bankart lesion, the periosteum is not completely torn, allowing the labrum to heal in a medially displaced position.

Question 61

A 75-year-old woman sustains a minimally displaced 3-part proximal humerus fracture. She is treated nonoperatively with a sling and early passive range of motion. What is the most commonly reported complication or outcome of this management strategy?

Explanation

Nonoperative management of 3-part proximal humerus fractures frequently results in healing with a varus malunion. This predictably leads to restricted range of motion, particularly in forward elevation and abduction, though many elderly patients tolerate this well functionally.

Question 62

A 45-year-old man falls while skiing and presents with weakness in internal rotation. Physical examination demonstrates increased passive external rotation compared to the contralateral side and a positive belly-press test. Which structure is most likely injured?

Explanation

The subscapularis is the primary internal rotator of the shoulder. Injury leads to weakness in internal rotation, positive belly-press and lift-off tests, and an increase in passive external rotation due to the loss of anterior soft-tissue restraint.

Question 63

A 35-year-old man arrives at the emergency department after a seizure. He complains of shoulder pain and an inability to externally rotate his arm. An AP radiograph demonstrates a "light bulb" sign. Which associated bony defect is most likely present?

Explanation

The clinical presentation and "light bulb" sign are classic for a posterior shoulder dislocation. This injury is highly associated with a reverse Hill-Sachs lesion, which is an impaction fracture of the anteromedial aspect of the humeral head.

Question 64

When comparing double-row to single-row rotator cuff repair techniques, biomechanical studies consistently demonstrate that double-row constructs provide which of the following?

Explanation

Biomechanical studies show that double-row repairs have superior ultimate load to failure, increased footprint contact area, and decreased gap formation compared to single-row repairs. However, this biomechanical superiority has not consistently translated to better clinical outcomes for small to medium tears.

Question 65

A 40-year-old man has a locked posterior shoulder dislocation that occurred 3 weeks ago. A CT scan reveals a reverse Hill-Sachs lesion involving 40% of the articular surface. What is the most appropriate surgical management?

Explanation

For a chronic locked posterior dislocation with a large reverse Hill-Sachs defect (typically 25-45% of the articular surface), a modified McLaughlin procedure is indicated. This involves open reduction and transferring the lesser tuberosity (with the subscapularis tendon) into the anteromedial defect to provide stability.

Question 66

A 25-year-old athlete has recurrent anterior shoulder instability despite a prior arthroscopic Bankart repair. An MRI arthrogram reveals extravasation of contrast extending inferiorly in the axillary pouch into the anatomic neck of the humerus forming a "J-sign". What is the most likely diagnosis?

Explanation

A Humeral Avulsion of the Glenohumeral Ligament (HAGL) lesion occurs when the inferior glenohumeral ligament is avulsed from its humeral insertion. The characteristic MRI arthrogram finding is a U-shaped or J-shaped extravasation of contrast in the axillary pouch.

Question 67

A 28-year-old elite volleyball player presents with painless weakness in external rotation. Forward elevation is full and strong. MRI reveals a paralabral cyst in the spinoglenoid notch. Which labral pathology is most commonly associated with this finding?

Explanation

Paralabral cysts in the spinoglenoid notch typically arise from posterior SLAP tears and compress the suprascapular nerve distal to the suprascapular notch. This causes isolated denervation and weakness of the infraspinatus muscle, leading to external rotation weakness.

Question 68

During open reduction and internal fixation of a proximal humerus fracture via a deltopectoral approach, how does the axillary nerve typically course in relation to the operative field?

Explanation

The axillary nerve originates from the posterior cord, runs anterior to the subscapularis initially, but quickly courses inferior to the shoulder capsule and exits the axilla posteriorly through the quadrilateral space. Surgeons must carefully protect it at the inferior border of the subscapularis.

Question 69

In evaluating a patient with anterior shoulder instability, the "glenoid track" concept is used to assess bone loss. A Hill-Sachs lesion is considered "off-track" if it:

Explanation

A Hill-Sachs lesion is "off-track" if its medial margin extends further medially than the medial margin of the calculated glenoid track. Such lesions will engage the anterior glenoid rim during abduction and external rotation, typically requiring a remplissage or bony augmentation to restore stability.

Question 70

A 72-year-old woman presents with severe shoulder pain and inability to elevate her arm actively past 40 degrees. Radiographs demonstrate superior migration of the humeral head with an acromiohumeral distance of 2 mm and mild glenohumeral osteoarthritis. What is the most appropriate definitive surgical management?

Explanation

Reverse total shoulder arthroplasty is indicated for cuff tear arthropathy and pseudoparalysis in the elderly, relying on the deltoid for elevation. Anatomic TSA is contraindicated due to the absence of a functional rotator cuff.

Question 71

A 22-year-old collegiate rugby player presents with his third episode of anterior shoulder dislocation. Advanced imaging reveals a 28% anteroinferior glenoid bone loss. Which of the following procedures is most appropriate to restore stability?

Explanation

Glenoid bone loss exceeding 20-25% in a contact athlete is an indication for a bony augmentation procedure, most commonly the Latarjet procedure. Soft tissue repairs alone have an unacceptably high failure rate in this setting.

Question 72

A 45-year-old male laborer sustained a massive, retracted, irreparable posterosuperior rotator cuff tear. He has intact subscapularis function, active forward elevation to 100 degrees, and no glenohumeral arthritis. Which of the following is the most appropriate surgical option to improve function?

Explanation

Latissimus dorsi or lower trapezius transfer is indicated for younger, active patients with massive, irreparable posterosuperior rotator cuff tears and no arthritis. Pectoralis major transfer is typically reserved for irreparable subscapularis tears.

Question 73

A 68-year-old woman sustains a 4-part proximal humerus fracture after a mechanical fall. She has significant medical comorbidities and severe osteoporosis. What is the most common complication if she is treated with open reduction and internal fixation (ORIF) using a locking plate?

Explanation

Intra-articular screw penetration is the most common complication following locking plate fixation of proximal humerus fractures, often due to osteoporotic settling and head collapse. Avascular necrosis is also a risk, but screw cutout is the most frequent reason for reoperation.

Question 74

A 30-year-old baseball pitcher presents with posterior shoulder pain during the late cocking phase of throwing. Examination shows a 25-degree deficit in internal rotation compared to the contralateral side. MRI arthrogram shows undersurface fraying of the posterior supraspinatus and a posterosuperior labral tear. What is the most likely diagnosis?

Explanation

Internal impingement occurs in overhead athletes during extreme abduction and external rotation, causing the undersurface of the rotator cuff to impinge against the posterosuperior labrum. It is highly associated with Glenohumeral Internal Rotation Deficit (GIRD).

Question 75

A 55-year-old man presents with anterior shoulder pain. On physical examination, he demonstrates weakness with internal rotation when the arm is placed behind the back and lifted away from the body. An MRI confirms an isolated full-thickness tear of the subscapularis tendon. Which physical examination test would also most likely be positive?

Explanation

The bear hug test and the lift-off test are specific for subscapularis pathology. Hornblower's evaluates the teres minor, while Jobe's test evaluates the supraspinatus.

Question 76

A 26-year-old woman complains of bilateral shoulder instability and pain. She has a history of joint hyperlaxity. Examination reveals a positive sulcus sign bilaterally and apprehension in multiple positions. She has failed 6 months of dedicated physical therapy. Which surgical intervention is most appropriate?

Explanation

For multidirectional instability (MDI) that fails conservative management, an inferior capsular shift (open or arthroscopic) is the procedure of choice to reduce redundant capsular volume. Bony procedures like Latarjet are contraindicated.

Question 77

A 42-year-old man undergoes arthroscopic rotator cuff repair. During the procedure, the surgeon decides to place an anchor in the posterosuperior aspect of the greater tuberosity. What structure is most at risk if the anchor is misplaced too medially near the glenoid articular margin?

Explanation

The suprascapular nerve courses through the spinoglenoid notch and supplies the infraspinatus. It is at risk during aggressive medial dissection or medial anchor placement near the posterior glenoid neck.

Question 78

A 65-year-old man falls on his outstretched dominant arm. He has a 3-part proximal humerus fracture with varus alignment. He undergoes ORIF with a locking plate. Postoperatively, he is noted to have inability to actively extend his wrist and fingers. What is the most likely cause?

Explanation

The radial nerve courses along the posterior humerus and is at risk if a drill or screw penetrates the posterior cortex too far distally during proximal humerus plating. Wrist and finger extension weakness clearly indicates a radial nerve palsy.

Question 79

A 50-year-old overhead athlete is diagnosed with a Type II SLAP tear. After failing conservative treatment, he undergoes arthroscopic surgery. Which of the following treatments is most supported by current literature for this patient demographic?

Explanation

In middle-aged and older patients (typically >40 years), biceps tenodesis provides more reliable pain relief and functional outcomes compared to SLAP repair, which has a significantly higher rate of postoperative stiffness and reoperation.

Question 80

Which of the following radiographic findings is most characteristic of a posterior shoulder dislocation on a standard anteroposterior (AP) view?

Explanation

On an AP radiograph, a posterior shoulder dislocation classically presents with the "lightbulb sign" due to fixed internal rotation of the humerus, hiding the greater tuberosity profile. Axillary views are required to definitively confirm the dislocation.

Question 81

A 38-year-old man sustains an anterior shoulder dislocation resulting in a massive, retracted rotator cuff tear. He is manually reduced in the emergency department. Three weeks later, he continues to have severe weakness in external rotation and elevation. He has a positive Hornblower's sign. An MRI demonstrates a retracted tear involving the supraspinatus and infraspinatus with grade 3 fatty infiltration. Which of the following is the most appropriate treatment?

Explanation

In a young patient with an irreparable posterosuperior cuff tear (indicated by high-grade fatty infiltration and retraction) and no arthritis, superior capsular reconstruction or tendon transfer is indicated. Primary repair has an unacceptably high failure rate with advanced fatty infiltration.

Question 82

A 28-year-old weightlifter presents with acute anterior shoulder pain and a visible bulge in his arm after a heavy bench press. Examination reveals weakness in adduction and internal rotation. MRI confirms a complete tear of the pectoralis major tendon at its insertion. What is the recommended treatment?

Explanation

Complete tears of the pectoralis major tendon at the humeral insertion in active individuals should be surgically repaired to restore strength, typically via a deltopectoral approach. Nonoperative treatment results in cosmetic deformity and significant weakness.

Question 83

A 78-year-old woman presents with a 4-part proximal humerus fracture. She has severe osteoporosis and a sedentary lifestyle. The fracture involves significant displacement of the tuberosities and valgus impaction of the humeral head. Which of the following is the primary advantage of reverse total shoulder arthroplasty (RTSA) over hemiarthroplasty for this patient?

Explanation

The primary advantage of RTSA over hemiarthroplasty for complex proximal humerus fractures in the elderly is that functional outcomes are less dependent on anatomic tuberosity healing. The reverse prosthesis design relies primarily on the deltoid muscle for elevation.

Question 84

A 45-year-old construction worker fell from a ladder, sustaining an anterior shoulder dislocation. The dislocation was reduced, but post-reduction radiographs show a residual 1.5 cm superior displacement of a greater tuberosity fracture fragment. What is the most appropriate management?

Explanation

Greater tuberosity fractures displaced more than 5 mm in the general population, or >3 mm in active/overhead workers, require surgical fixation (ORIF). Leaving it displaced can lead to severe subacromial impingement and loss of rotator cuff function.

Question 85

A 24-year-old competitive rugby player presents with recurrent anterior shoulder instability. A CT scan demonstrates 28% anterior glenoid bone loss. Which of the following is the most appropriate surgical management?

Explanation

Anterior glenoid bone loss greater than 20-25% is a contraindication to isolated soft-tissue stabilization. The Latarjet procedure (coracoid transfer) is the treatment of choice to restore the bony arc and provide a sling effect.

Question 86

A 65-year-old man presents with inability to actively externally rotate his shoulder and a positive hornblower's sign following a massive rotator cuff tear. Assuming the subscapularis is intact and the tear is irreparable, which tendon transfer is most appropriate to restore external rotation?

Explanation

Latissimus dorsi or lower trapezius transfers are indicated for massive, irreparable posterosuperior rotator cuff tears to restore active external rotation and forward elevation. Pectoralis major transfers are typically reserved for irreparable subscapularis tears.

Question 87

When evaluating a proximal humerus fracture for the risk of avascular necrosis (AVN), which of the following radiographic findings is the most reliable predictor of humeral head ischemia according to Hertel's criteria?

Explanation

Hertel described several predictors of humeral head ischemia. The most reliable indicator is a metaphyseal head extension (calcar length) of less than 8 mm combined with disruption of the medial hinge, as these compromise the posteromedial vessel supply.

Question 88

A 30-year-old man sustained a posterior shoulder dislocation during a seizure. Radiographs reveal a reverse Hill-Sachs lesion involving 35% of the anterior humeral head articular surface. Which of the following is the most appropriate surgical intervention?

Explanation

A reverse Hill-Sachs lesion involving 20% to 40% of the articular surface is best treated with a McLaughlin procedure or its modification (transfer of the lesser tuberosity). Lesions greater than 40-50% generally require arthroplasty.

Question 89

A 74-year-old woman with severe osteoporosis sustains a 4-part proximal humerus fracture. She has a documented history of a massive, retracted, and irreparable rotator cuff tear on the same side. The most appropriate surgical treatment is:

Explanation

Reverse total shoulder arthroplasty is indicated for older patients with complex proximal humerus fractures and concurrent rotator cuff arthropathy. It relies on the deltoid for overhead function and has more reliable outcomes than hemiarthroplasty when tuberosity healing is compromised.

Question 90

A 28-year-old volleyball player complains of isolated, painless weakness in external rotation of her dominant shoulder. MRI reveals a paralabral cyst in the spinoglenoid notch. Which of the following physical examination findings is most likely present?

Explanation

A cyst at the spinoglenoid notch typically compresses the suprascapular nerve after it has innervated the supraspinatus. This results in isolated denervation and subsequent atrophy of the infraspinatus muscle.

Question 91

A 19-year-old gymnast presents with bilateral shoulder pain and a sensation of "slipping." Examination shows a sulcus sign of 2 cm bilaterally, positive apprehension, and generalized ligamentous laxity. There is no history of a distinct traumatic dislocation. What is the most appropriate initial management?

Explanation

Multidirectional instability (MDI) is typically atraumatic and bilateral, characterized by generalized laxity. The mainstay of initial treatment is a prolonged course (minimum 3-6 months) of structured physical therapy focusing on dynamic stabilizers.

Question 92

A patient with a massive rotator cuff tear demonstrates "pseudoparalysis" of the shoulder, being unable to actively elevate the arm past 60 degrees. Anesthetic injection into the subacromial space does not improve active motion. What is the primary biomechanical deficit in this shoulder?

Explanation

Pseudoparalysis in massive rotator cuff tears occurs due to the loss of the coronal and transverse force couples. This prevents the humeral head from being compressed into the glenoid, allowing the deltoid to cause superior migration rather than elevation.

Question 93

When performing open reduction and internal fixation (ORIF) of a 2-part surgical neck fracture of the proximal humerus, placement of a screw into the inferomedial quadrant of the humeral head (calcar screw) is primarily intended to:

Explanation

The inferomedial "calcar" screws in locking plate constructs for proximal humerus fractures provide critical medial column support. This significantly reduces the risk of postoperative varus collapse.

Question 94

During an arthroscopic anterior stabilization procedure, the surgeon identifies an avulsion of the anterior labrum where the intact anterior scapular periosteum has stripped and displaced medially on the glenoid neck. What is the correct term for this lesion?

Explanation

An ALPSA lesion involves an anterior labral tear where the scapular periosteum remains intact but strips medially. It allows the labroligamentous complex to heal in an incompetent, medially displaced position and must be mobilized laterally during repair.

Question 95

A 50-year-old man presents with a suspected subscapularis tendon rupture after a fall. Which of the following physical examination tests is most specific and sensitive for diagnosing a full-thickness tear of the upper border of the subscapularis tendon?

Explanation

The bear hug and belly-press tests are highly specific and sensitive for upper subscapularis tears. In contrast, the lift-off test requires full internal rotation and typically assesses the lower subscapularis muscle belly.

Question 96

In the context of anterior shoulder instability, the "glenoid track" concept is used to determine whether a Hill-Sachs lesion will engage. Which of the following correctly defines an "off-track" Hill-Sachs lesion?

Explanation

An "off-track" Hill-Sachs lesion has a medial margin that extends further medial than the medial margin of the glenoid track. This lesion will engage the anterior glenoid rim during abduction and external rotation, often necessitating a remplissage.

Question 97

A 65-year-old patient underwent a hemiarthroplasty for a complex 4-part proximal humerus fracture. Postoperatively, radiographs show that the greater tuberosity has migrated superiorly and healed in a malunited position. This complication is most likely to result in:

Explanation

Tuberosity malposition, particularly superior migration, is a leading cause of failure after hemiarthroplasty for proximal humerus fractures. Superior malunion leads to severe subacromial impingement, blocking active elevation and causing profound rotator cuff dysfunction.

Question 98

A superior capsular reconstruction (SCR) is planned for a 55-year-old laborer with an irreparable, massive supraspinatus and infraspinatus tear. To optimize the biomechanical success of the SCR, which of the following native structures MUST be intact or repairable?

Explanation

Superior capsular reconstruction acts to tether the humeral head and prevent superior migration. For it to function correctly and restore glenohumeral kinematics, the anterior structures, specifically the subscapularis tendon, must be intact or fully repairable.

100 High-Yield Orthopedic MCQs: Shoulder & Elbow | Mock Exam 251

AAOS & ABOS Shoulder Board Review MCQs (Set 4): Rotator Cuff, Instability & Proximal Humerus

Key Takeaway

AAOS & ABOS Shoulder Board Review MCQs (Set 4): Rotator Cuff, Instability & Proximal Humerus

Chapter Index