Shoulder and Elbow cases ulnar collateral ligament instability

A 21-year-old, right-hand-dominant, collegiate pitcher presents to the office with elbow pain and loss of velocity and control over the last 6 weeks. Examination reveals tenderness along the medial aspect of the elbow, negative Tinel sign, and pain with valgus stress through the mid-arc of motion. He has no pain with wrist range of motion or forearm pronation and supination. Imaging study is shown below (Fig. 2–115).

 

 

 

Figure 2–115

 

What anatomic structure is the primary cause of the patient’s symptoms?

1. Ulnar collateral ligament

2. Ulnar nerve

3. Common flexor origin

4. Olecranon osteophytes

5. Biceps tendon

 

Discussion

The correct answer is (A). This patient has pain with mid-flexion valgus stress suggesting an injury to his ulnar collateral ligament. Throwing athletes can have multiple causes for pain at the medial elbow, which can be elucidated by history and physical examination. This patient has a negative Tinel sign and no numbness, tingling or weakness to suggest ulnar nerve injury. Likewise, the flexor pronator mass may become irritated in pitchers, but it is not the primary cause of this patient’s symptoms. His pain is not at terminal extension, and therefore olecranon osteophytes or valgus extension overload would not seem to be the cause. He does not have any findings suggestive of biceps tendon pathology.

During which phase of throwing is the ulnar collateral ligament most likely to be injured?

1. Wind up

2. Early cocking

3. Late cocking

4. Ball release

5. Deceleration

 

Discussion

The correct answer is (C). The late cocking and early acceleration phase of overhead throwing places the greatest amount of valgus stress on the elbow (see Fig. 2–116). At this point, the elbow is in mid flexion while the forearm lags behind the upper arm, producing a valgus moment at the elbow. The anterior band of the ulnar collateral ligament is the primary restraint to valgus stress between 30 and 120 degrees of flexion. The wind up phase does not place any stress on the elbow. In early cocking, the rotator cuff and deltoid are active and susceptible to injury. Ball release occurs after acceleration as the forearm is brought forward. At this point, the valgus stresses on the UCL are dissipated. Finally, in deceleration, the posterior compartment of the elbow and elbow flexors are subject to stress to prevent hyperextension.

 

 

Figure 2–116 Phases of throwing: The greatest valgus stress at the elbow occurs during the late cocking and early acceleration phases of throwing. (Reproduced with permission from Chen FS, Rokito AS, Jobe FW. Medial elbow problems in the overhead-throwing athlete. J Am Acad Orthop Surg. 2001;9(2):99–113.)

 

Which of the following is the most sensitive physical examination finding for ulnar collateral ligament injury?

1. Lateral pivot shift test

2. Pain with resisted wrist flexion

3. Static valgus stress test

4. Palpable medial ligamentous laxity

5. Moving valgus stress test

 

Discussion

The correct answer is (E). The lateral pivot shift test is used to assess the lateral ulnar collateral ligament and suggests posterolateral rotatory instability. Pain with resisted wrist flexion indicates inflammation at the common flexor origin, and is suggestive of medial epicondylitis. The moving valgus stress test is highly sensitive (100%) and specific (75%) for ulnar collateral ligament injury, as it reproduces the stresses and elbow positions present during throwing. Pain with static valgus testing is not as accurate as the moving valgus stress test (sensitivity 65%, specificity 50%) as it does not test an arc of motion that pitchers experience. Palpable ligamentous laxity is poorly sensitive (19%) but highly specific (100%).

The moving valgus stress test is performed with the patient upright and the shoulder abducted 90 degrees (Fig. 2–117). With the elbow flexed, a valgus stress is applied to the elbow until the shoulder reaches full external rotation. While a constant valgus torque is maintained, the elbow is quickly extended to 30 degrees.

 

 

 

Figure 2–117 Reproduced with permission from O’Driscoll SW, Lawton RL, Smith AM. The “moving valgus stress test” for medial collateral ligament tears of the elbow. Am J Sports Med. 2005 Feb;33(2):231–9.

 

The patient undergoes conservative treatment consisting of rest and physical therapy, followed by a progressive throwing program. However, he is unable to return to throwing after 3 months. He elects for ulnar collateral ligament reconstruction.

What types of outcomes have been seen with ulnar collateral ligament reconstruction with professional pitchers?

1. High rates of persistent elbow pain and retirement from sport

2. Loss of velocity and performance

3. High rate of return to play at a similar level

4. 30% rate of revision surgery

 

Discussion

The correct answer is (C). Studies in Major League Baseball have shown that over 80% of pitchers returned to the major leagues at a mean 20 months after UCL reconstruction, while over 97% return to major and minor leagues combined. Meanwhile, the revision rate for surgery is approximately 4%. Pitch velocity and common performance measurements do not seem to differ from pre-injury levels.

What is the most common surgical complication seen with ulnar collateral ligament reconstruction?

1. Postoperative stiffness requiring reoperation

2. Ulnar neuropathy

3. Superficial infection

4. Tenderness at graft harvest site

5. Permanent cutaneous sensory deficit

Discussion

The correct answer is (B). The overall complication rate after ulnar collateral ligament reconstruction is 10% (range 3–25%). Ulnar neuropathy is the most commonly reported complication after ulnar collateral ligament reconstruction ranging from 2% to 21%. In one study, performance of obligatory ulnar nerve transposition led to 75% excellent results and 14% with ulnar neuropathy. Without obligatory nerve transposition, that study found 89% excellent results and 6% rate of ulnar neuropathy. Studies report a 1% rate of stiffness requiring reoperation. Cutaneous nerve injuries after Tommy John surgery tend to be transient neuropraxias as opposed to permanent deficits. Infection and graft site tenderness are not as common complications as ulnar neuropathy.

 

Objectives: Did you learn...?

 

Identify and evaluate patients with ulnar collateral ligament instability?

 

Comprehend anatomic and biomechanical considerations for medial elbow instability?

 

Understand the role for surgery and the outcomes of ulnar collateral ligament reconstruction?