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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.