Orthopedic Teaching Cases 2023, Jan, 18 | 12:00 am

Shoulder and Elbow cases acromioclavicular arthritis

A 55-year-old, right-hand-dominant female presents with right shoulder pain for 6 months. She localizes the pain over the anterior and superior aspect of her shoulder. The pain is worsened when she is cleaning her contralateral axilla, while

showering, and fastening or unhooking her bra. The pain sometimes radiates down her arm. She has taken ibuprofen with some improvement, and she has undergone a course of physical therapy (PT) that did not relieve symptoms. She is continuing her home exercise program (HEP). On examination, the patient is tender over the acromioclavicular (AC) joint. Her range of motion (ROM) is normal, but with increased pain. She has a negative Sperling test and a positive cross-body adduction test. She has a negative Hawkins sign and Neer test. She also has a positive O’Brien’s test when in supination.

Based on the information given thus far, what is the most likely diagnosis?

  1. Cervical radiculopathy

  2. Glenohumeral arthritis

  3. SLAP tear

  4. Acromioclavicular joint arthritis

  5. Subacromial impingement

 

Discussion

The correct answer is (D). The acromioclavicular (AC) joint is a small, diarthrodial joint with a fibrocartilage disk separating the two articular surfaces. This disk is thought to begin degenerating in the second decade of life and undergoes rapid degeneration until it is no longer functional beyond the fourth decade. Because the AC joint has a small contact area experiencing large loads, it is a frequent source of clinical symptoms. Symptoms are most often due to primary osteoarthritis, posttraumatic arthritis, or distal clavicle osteolysis. The patient had a negative Sperling test and lack of neurological pain (Answer A). The patient has normal ROM, a negative O’Brien’s test in pronation, and a negative Neer and Hawkin’s test (Answers B, C, and E).

Which radiographic view is the most accurate view to evaluate suspected AC joint pathology?

  1. Anteroposterior view

  2. Stress view

  3. Axillary lateral view

  4. Zanca view

  5. Stryker notch view

 

Discussion

The correct answer is (D). The Zanca view is an AP radiograph obtained by angling the x-ray beam 10 to 15 degrees superiorly and decreasing the kilovoltage (Fig. 2–72A–C). The AP and axillary views should be routinely obtained for investigation of shoulder pathology, but are not the most accurate for AC joint pathology. Stress views have been used in the past to help differentiate type II from type III AC joint instability injuries but are not helpful or indicated in AC joint osteoarthritis. A stryker notch view is used for evaluation of Hill–Sachs lesions of the humeral head after a glenohumeral dislocation.

 

 

 

Figure 2–72 A: Zanca view projection. B: AP view of the shoulder that overpenetrates and does not show AC joint well. C: Zanca view demonstrates better ACJ detail. (Reproduced with permission from Shaffer BS: Painful conditions of the acromioclavicular joint. J Am Acad Orthop Surg 1999;7:176–188.)

 

What AC joint structure(s) is predominantly responsible for maintaining anteroposterior (AP) stability?

  1. Coracoacromial ligament

  2. Acromioclavicular ligaments

  3. Conoid ligament

  4. Trapezoid ligament

  5. Coracohumeral ligament

 

Discussion

The correct answer is (B). The AC joint capsular ligaments (acromioclavicular ligaments) are predominantly responsible for maintaining stability in the AP plane. The coracoacromial ligament does not play a significant role in AC joint stability. The conoid and trapezoid ligaments primarily resist superior and axial translation. The coracohumeral ligament plays a role in glenohumeral stability, not AC joint stability.

What is the most appropriate next step in treating this patient with AC joint arthritis?

  1. Injection with local anesthetic and corticosteroid

  2. Order more PT focusing on strengthening and stretching of shoulder girdle

  3. Recommend activity modification, anti-inflammatory medications, and plan to follow-up with patient in 6 weeks

  4. Arthroscopic Mumford procedure

  5. Open distal clavicle resection

 

Discussion

The correct answer is (A). Based on the information provided, the patient has continued pain but does not have loss of function. This (and the fact that she has failed other nonoperative measures including anti-inflammatory medication and PT) would make an intra-articular injection the most appropriate next step. Injections can be used both diagnostically and therapeutically. Answers B and C are incorrect because the patient has already undergone these treatments and is currently undergoing a HEP with activity modification. Indications for operative management of AC joint osteoarthritis include continued pain and loss of function despite a full course of nonoperative treatment. This patient does not have loss of function.

All of the following are advantages of arthroscopy when compared to open distal clavicle resection, EXCEPT?

  1. Accelerated recovery

  2. Ability to preserve AC ligaments, joint capsule, and deltotrapezial fascia

  3. Ability to treat concomitant intra-articular glenohumeral lesions

  4. Ability to treat concomitant subacromial lesions

  5. Demonstrates significant improvement in VAS pain scores and SF-36 quality of life scores

Discussion

The correct answer is (E). Both open and arthroscopic techniques demonstrate improved VAS pain scores and SF-36 quality of life scores. Answers A, B, C, and D are all advantages of the arthroscopic technique for distal clavicle resection over the open technique.

 

Objectives: Did you learn...?

 

Recognize the clinical presentation of acromioclavicular arthritis?

 

Differentiate between primary osteoarthritis, posttraumatic arthritis, and distal clavicle osteolysis?

 

Treat a patient with AC joint arthritis?

 

Recognize the advantages of arthroscopic versus open distal clavicle resection?