AAOS Upper Extremity MCQs (Set 5): Shoulder, Elbow & Wrist Injuries | ABOS Review

Based on the findings, the treatment of choice is resection of the sternoclavicular joint. Antibiotic therapy, repeat aspirations, hyperbaric oxygen, and simple irrigation and debridement are generally ineffective and associated with a high rate of recurrence.

The modified posterior approach with elevation of the medial and lateral heads of the triceps can provide exposure of 94% of the humeral shaft. The traditional posterior triceps-splitting approach exposes 55% of the humeral shaft. DeFranco MJ, Lawton JN: Radial nerve injuries associated with humeral fractures. J Hand Surg Am 2006;31:655-663.

Patients older than age 40 years at the time of initial anterior dislocation have low rates of redislocation; however, 15% of these patients experience a rotator cuff tear. Moreover, there is a dramatic increase (up to 40%) in the incidence of rotator cuff tears in patients older than age 60 years. Axillary nerve injury may occur but is less common than rotator cuff tear. Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 273-284.

Developmental dislocation of the radial head most frequently presents as a painless mass over the posterior aspect of the elbow. Patients do not have feelings of elbow subluxation but may report pain or clicking. Limitation of motion is most frequently found in the pronation and supination arc rather than in flexion and extension. Lloyd-Roberts GC, Bucknill TM: Anterior dislocation of the radial head in children-etiology: Natural history and management. J Bone Joint Surg Am 1977;58:402.

According to a recent study, cemented pegged glenoid components had fewer radiolucent lines initially and at 2-year follow-up when compared to a cemented keeled design. Curve-backed designs have also shown fewer radiolucent lines when compared to flat-backed designs. Oversizing the glenoid can lead to impaired rotator cuff function and decreased range of motion. An off-centered glenoid can lead to early loosening. Gartsman GM, Elkousy HA, Warnock KM, et al: Radiographic comparison of pegged and keeled glenoid components. J Shoulder Elbow Surg 2005;14:252-257. Szabo I, Buscayret F, Edwards TB, et al: Radiographic comparison of flat-back and convex-back glenoid components in total shoulder arthroplasty. J Shoulder Elbow Surg 2005;14:636-642.

The image shows a view of the radiocapitellar joint from an anterior medial portal. The radial nerve lies on the elbow capsule at the midportion of the capitellum. It is at risk for injury when capsular excision is performed in this region. Field LD, Altchek DW, Warren RF, et al: Arthroscopic anatomy of the lateral elbow: A comparison of three portals. Arthroscopy 1994;10:602-607.

The patient has symptomatic primary osteoarthritis of the elbow with multiple loose bodies. Given his age and occupation, an elbow arthroplasty is not an option. Arthroscopic debridement and removal of loose bodies has been shown to be effective for osteoarthritis of the elbow. Gramstad GD, Galatz LM: Management of elbow osteoarthritis. J Bone Joint Surg Am 2006;88:421-430.

Functional bracing has been demonstrated to have a very high rate of healing without any functional limitations in a large series of patients. Surgery is reserved for "floating elbows," open injuries, neurovascular injuries, and those fractures that go on to nonunion. Sarmiento A, Zagorski JB, Zych GA, et al: Functional bracing for the treatment of fractures of the humeral diaphysis. J Bone Joint Surg Am 2000;82:478-486.

The patient has end-stage shoulder arthritis with posterior glenoid erosion and large humeral osteophyte formation. Since the rotator cuff is likely intact, the reverse total shoulder arthroplasty is unnecessary. All the remaining procedures may provide symptomatic relief in appropriate patients; however, for most patients, total shoulder arthroplasty has been associated with the most predictive pain relief and functional improvements. Bryant D, Litchfield R, Sandow M, et al: A comparison of pain, strength, range of motion, and functional outcomes after hemiarthroplasty and total shoulder arthroplasty in patients with osteoarthritis of the shoulder: A systemic review and meta-analysis. J Bone Joint Surg Am 2005;87:1947-1956. Edwards TB, Kadakia NR, Boulahia A, et al: A comparison of hemiarthroplasty and total shoulder arthroplasty in the treatment of primary glenohumeral osteoarthritis: Results of a multicenter study. J Shoulder Elbow Surg 2003;12:207-213.

There are four ways in which a plate acts: compression, tension bend, bridge or spanning, and buttress. Since there is no cortical contact with the large span of comminution, this plate is acting as a bridge plate. A bridge plate is defined as when the plate is used as an extramedullary splint attached to the two main fragments, leaving the comminution untouched.

The tetracycline family of medications can stain teeth and bone in skeletally immature patients and as a result should be avoided in those patients. The remaining antibiotics have no known specific contraindication to use in children.

A common side effect of interscalene nerve block for shoulder surgery is the blockade of the ipsilateral phrenic nerve. This, in turn, results in paresis of the diaphragm and up to a 30% reduction in pulmonary function volumes. Therefore, interscalene nerve block generally is not recommended for patients whose respiratory function is compromised. Other relative and absolute contraindications for interscalene nerve blocks include allergy to local anesthetics, infection at the injection site, uncontrolled seizure disorder, coagulation abnormality, and preexisting neurologic injury. Chelly JE: Indications for upper extremity blocks, in Chelly JE (ed): Peripheral Nerve Blocks, ed 2. Philadelphia, PA, Lippincott Williams & Wilkins, 2004, pp 19-27.

Clavicular fractures are occasionally complicated by injury to the brachial plexus. A displaced bone fragment pressing on the posterior cord proximal to the upper subscapularis nerve would account for these findings. Jobe CM, Coen MJ: Gross anatomy of the shoulder, in Rockwood CA, Matsen FA, Wirth MA, et al (eds): The Shoulder. Philadelphia, PA, WB Saunders, 2004, vol 2, pp 1078-1079.

Osteochondritis dissecans occurs in the older child or adolescent (typically older than age 13 years). It involves the lateral compartment. The etiology is felt to be microtraumatic vascular insufficiency from repetitive rotatory and compressive forces. MRI typically shows separation of cartilage from the capitellum and chondral fissuring. Panner's disease is usually seen in children younger than age 10 years, involves the entire capitellar ossific nucleus, and resolves typically with no residual deformity or late sequelae. There is no evidence of ligamentous injury. Defelice GS, Meunier MJ, Paletta GA: Elbow injury in the adolescent athlete, in Altchek DW, Andrews JR (eds): The Athlete's Elbow. New York, NY, Lippincott Williams & Wilkins, 2001, pp 231-248.

Mucoid cysts are commonly associated with DIP joint arthritis. Two treatment options are commonly used: (1) aspiration/drainage and injection of corticosteroid and (2) surgical excision. When performing the surgery, excision of the bony osteophytes about the DIP joint is helpful in achieving a cure. There are no reports of significant benefit with nail removal or partial ligament or extensor tendon resection. Some authors have advocated skin excision and rotational flaps for wound coverage, but this is somewhat controversial. Rizzo M, Beckenbaugh RD: Treatment of mucous cysts of the fingers: Review of 134 cases with minimum 2-year follow-up evaluation. J Hand Surg Am 2003;28:519-524.

The patient has internal impingement. Internal impingement is commonly seen in overhead throwing athletes. When positioned in the extreme cocking phase of the throwing cycle, the posterior glenoid impacts the articular surface of the infraspinatus and posterior fibers of the supraspinatus tendon. This impact can cause partial-thickness rotator cuff tearing and posterosuperior labral lesions. She has no evidence of anterior shoulder instability, and her range of motion is excellent which rules out adhesive capsulitis. Subacromial impingement is identified with anterolateral shoulder pain with internal rotation in the abducted position. A full-thickness rotator cuff tear in a 22-year-old individual would require significant trauma and would likely result in pain at rest and with lifting. Meister K, Buckley B, Batts J: The posterior impingement sign: Diagnosis of rotator cuff and posterior labral tears secondary to internal impingement in overhand athletes. Am J Orthop 2004;33:412-415.

EIP transfer results in no functional deficit. If the tendon is cut proximal to the sagittal band, there will be no extensor deficit. Browne EX, Teague MA, Snyder CC: Prevention of extensor lag after indicis proprius transfer. J Hand Surg Am 1979;4:168-172.

All of these complications have been documented after interscalene nerve block. Other serious complications such as cardiac arrest and respiratory distress have also been noted. However, the most common complication after interscalene nerve block appears to be temporary paresthesia to the hand that can occur in up to 2.3% of the patients. Bishop JY, Sprague M, Gelber J, et al: Interscalene regional anesthesia for shoulder surgery. J Bone Joint Surg Am 2005;87:974-979.

The patient has end-stage arthritis of the elbow with advanced joint destruction. At this point, nonsurgical management is unlikely to provide much relief of symptoms. Arthroscopic procedures can provide relief, but it is likely to be incomplete and unpredictable. The most reliable surgical option is total elbow arthroplasty. Currently, semiconstrained components are generally preferred because constrained components have been associated with a high rate of early prosthetic loosening. Little CP, Graham AJ, Karatzas G, et al: Outcomes of total elbow arthroplasty for rheumatoid arthritis: Comparative study of three implants. J Bone Joint Surg Am 2005;87:2439-2448.

The radial nerve is 4 to 7 mm from the anterolateral portal, which is placed 1 cm anterior and 3 cm proximal to the lateral epicondyle. The posterior interosseous nerve can lie 1 to 14 mm from the portal site. Andrews JR, Carson WG: Arthroscopy of the elbow. Arthroscopy 1985;1:97-107.

Spontaneous swelling with the appearance of joint subluxation may be associated with an acute, subacute, or chronic bacterial infection of the sternoclavicular joint. Common causes of infection include bacteremia, rheumatoid arthritis, alcoholism, intravenous drug use, and chronic debilitating diseases. Subclavian vein catheterization and renal dialysis can predispose patients to sepsis and osteomyelitis of the sternoclavicular joint. Renoult B, Lataste A, Jonon B, et al: Sternoclavicular joint infection in hemodialysis patients. Nephron 1990;56:212-213.

When comparing closed reduction and pinning to ligament reconstruction, the reconstruction group had slightly better abduction and pinch strength. The volar oblique ligament usually tears off the first metacarpal in a subperiosteal fashion. In this young patient, motion-sparing procedures are preferred. Simonian PT, Trumble TE: Traumatic dislocation of the thumb carpometacarpal joint: Early ligamentous reconstruction versus closed reduction and pinning. J Hand Surg Am 1996;21;802-806.

Concavity compression is a stabilizing mechanism by which muscular compression of the humeral head into the glenoid fossa stabilizes the glenohumeral joint against shear forces. This is dependent on the depth of the concavity and the magnitude of the compressive force. Lee SB, Kim KJ, O'Driscoll SW, et al: Dynamic glenohumeral stability provided by the rotator cuff muscles in the mid-range and end-range of motion: A study in cadavera. J Bone Joint Surg Am 2000;82:849-857.

In a traditional plate system, fracture security depends on the friction between the plate and the underlying bone. Bicortical fixation will decrease the toggle and improve stability. Locking plates absorb axial forces transmitted from the screws. Such plates do not require plate compression against the bone, thus preserving periosteal blood supply. Nana AD, Joshi A, Lichtman DM: Plating of the distal radius. J Am Acad Orthop Surg 2005;13:159-171.

The anterior band of the ulnar collateral ligament provides the greatest restraint to valgus stress in the elbow. The posterior band is taut in flexion and resists stress between 60 degrees and full flexion. The annular ligament stabilizes the radial head. The flexor/pronator mass are important dynamic stabilizers of the medial elbow. Ahmad CS, ElAttrache NS: Elbow valgus instability in the throwing athlete. J Am Acad Orthop Surg 2006;14:693-700. Regan WD, Korinek SL, Morrey BF, et al: Biomechanical study of ligaments around the elbow joint. Clin Orthop Relat Res 1991;271:170-179.