Lucca Lacheta, MD; Maj. Travis J. Dekker, MD, MC, USAF; and Peter J. Millett, MD, MSc
Treatment of the aging athlete with early glenohumeral osteoarthritis (GHOA) and as a sequelae of shoulder instability is challenging because shoulder arthroplasty may not be the treatment of choice in this population. The increased risk of GHOA of the shoulder joint in patients with shoulder instability has been well documented1,2 (Figure 28-1). The cause of these degenerative changes remains unclear. The trauma of shoulder luxation itself certainly plays a significant role in the initial injury to the articular cartilage. This theory is supported by the fact that even in those who undergo successful nonoperative treatment GHOA still develops in about 50% of cases.2 Unfortunately, neither open nor arthroscopic operative techniques have been able to prevent the development of GHOA completely.1,3,4 Although the majority of patients show only minor pathological changes, the overall incidence in long-term studies is around 60% to 80%.1,3,4 Age at the time of the first dislocation and at the time of operative stabilization, the number of dislocations before surgical intervention, and the number of anchors used have been shown to be risk factors.1 Historically, nonanatomic procedures with tightening of the subscapularis tendon to limit external rotation by transecting then overlapping the medial and lateral segments (Putti-Platt) or by moving the insertion point more laterally and distally (Magnuson-Stack) were shown to result in an increased rate of GHOA.5,6 In the setting of coracoid transfer procedures, recent long-term analysis with follow-up greater than 10 years has shown posttraumatic GHOA occurring in up to 38% of patients.7 Older age, high-demand sports, and lateral positioning of the transferred coracoid in relation to the glenoid rim promotes the development of GHOA.7–10 Avoidance of overtightening the capsule tissue during initial surgical treatment, correct hardware placement, and maybe new-generation anchor materials (all-suture soft anchors) can help to reduce or even avoid the risk of development of GHOA. Furthermore, an early stabilization after first-time dislocation and technically correct and well-performed surgery with no iatrogenic injuries may prevent the development of GHOA. When it comes to early or even end-stage GHOA, various treatment options have been described that will be summarized in this chapter focusing on the management of the aging athlete with glenohumeral instability sequelae.
Many historical surgical procedures have been associated with the development of GHOA (eg, Putti-Platt, Magnuson-Stack) with stiffness and tightness of the glenohumeral joint. Hawkins and Angelo reported on a series of patients who after undergoing a Putti-Platt procedure developed painful GHOA at 13.2 years after surgery.6 Provencher termed this condition capsulorrhaphy arthropathy to describe GHOA developed because of excessive soft-tissue tightening.11 Historically, subscapularis tendon lengthening was one treatment option for those patients to increase external rotation that was first described by Neer et al,12 by dissecting the subscapularis tendon free and lengthening by a coronal-plane z-plasty. Nicholson and colleagues reported their technique of subscapularis lengthening in shoulder arthroplasty with outcomes in 27 patients.13 External rotation improved to 48 degrees postoperatively with more than half the patients reporting a decrease in subscapularis function. Owing to poor functional results, therefore, this procedure is not usually recommended and serves as a salvage procedure alone.13,14
COMPREHENSIVE ARTHROSCOPIC MANAGEMENT PROCEDURE FOR EARLY GLENOHUMERAL OSTEOARTHRITIS
Joint-preserving arthroscopic management options for degenerative joint disease in young patients have been used to address different pain generators that are involved in the pathoanatomy related to GHOA to reduce pain, improve shoulder function, and to delay or even avoid the need for total joint replacement. Key considerations of this comprehensive approach to mitigating GHOA include addressing all the various factors that can cause pain and limit function. The pathologic adaptive changes seen with glenohumeral arthritis are the following: capsular contracture, loose bodies, biceps tenosynovitis, inferior humeral osteophyte formation with axillary nerve compression, subcoracoid impingement, and subacromial spurs. Arthroscopically, the surgeon can perform debridement, chondroplasty, synovectomy, loose body removal, capsular release, subacromial decompression with acromioplasty, subcoracoid decompression with coracoidplasty, humeral osteoplasty, axillary nerve decompression, and biceps tenodesis. The goal of these procedures is to treat mechanical and inflammatory causes of pain and to improve functional limitations. Although data are still emerging, clinical studies report that the comprehensive arthroscopic approach to GHOA improves function and reduces pain in short- and mid-term follow-up periods.
The goal of various arthroscopic management techniques is to treat potential causes of pain and address functional limitations associated with GHOA. Initially, arthroscopic management consisted of intra-articular debridement of the glenohumeral joint alone with resection of synovitis and loose bodies. The rationale behind arthroscopic debridement is to simply remove possible sources of mechanical irritation, creating a less painful environment for the patient’s shoulder.15,16 Additionally, capsular release was added to the arthroscopic management to increase the effect of restoring shoulder function and range of motion,17 which leads both to pain relief and increase in patient satisfaction. Another well-known source of pain addressed arthroscopically in the osteoarthritic shoulder is pathology associated with the long head of the biceps tendon. Biceps pathologies such as tendinitis, hourglass deformity, or pulley lesions warrant a tenotomy with or without later tenodesis.18–22
The senior author has combined several previous arthroscopic techniques used to treat GHOA with a number of additional key procedures23—the so-called comprehensive arthroscopic management (CAM) procedure. A detailed technique description has previously been published23
An important point and source of pain are inferior humeral head osteophytes, also described as the goat’s beard deformity, which are frequently seen in patients with advanced GHOA (Figure 28-2). Owing to its proximity to the axillary nerve, frequent impingement of the osteophytes on the nerve can result in pain and dysfunction of the teres minor with observed fatty infiltration.24
In clinical practice, inferior humeral head osteophytes are addressed when they are large and when pain in the axillary nerve distribution exists. The use of preoperative and postoperative electromyography may be of use in the future.
To address the inferior humeral osteophytes, an accessory posteroinferior portal is established to facilitate resection. To confirm the amount of osteophyte resection intraoperatively fluoroscopy is used (Figure 28-3). In case of nerve impingement symptoms, the inferior capsule is opened to access the axillary nerve for neurolysis (Figure 28-4). Clinical signs for nerve impingement can be muscle weakness or atrophy, seen on the preoperative magnetic resonance imaging (MRI), or it can be visualized arthroscopically.
Additional arthroscopic shoulder procedures can be added as indicated. If clinical signs of subacromial impingement are present, with positive provocative testing, increased subacromial spurs on radiographs according to the Bigliani classification, or increased bursal inflammation on MRI, a subacromial decompression is performed (Figure 28-5). If patients present with anterior shoulder pain during internal rotation and arthroscopic findings of fraying or tearing of the upper border of the subscapularis tendon as a sign for anterior subcoracoid impingement, a subcoracoid decompression can be performed; there are also loose bodies frequently present in the subcoracoid space (Figure 28-6). Radiographically, a coracohumeral distance of less than 8 mm (in women) or less than 10 mm (in men) with associated symptoms may warrant arthroscopic treatment.25,26
In cases of focal chondral defects, microfracture is performed to stimulate the subchondral bone for fibrocartilage stimulation. This step should be performed last during the CAM procedure to avoid washing out the nascent clot with arthroscopic fluid.27
Subpectoral biceps tenodesis is performed in most cases at the end of the case. Even though little to no differences are observed in clinical outcome between tenodesis and tenotomy of the long head of the biceps tendon, many surgeons and patients prefer tenodesis because it is associated with higher patient satisfaction and fewer cosmetic problems.21 The senior author’s preferred technique of biceps tenodesis is a subpectoral biceps tenodesis with interference screw fixation below the bicipital groove, with resection of the tenosynovitis and frayed proximal part of the biceps tendon.28
The goal of these arthroscopic procedures is to address all mechanical causes of pain and functional impairment associated with GHOA. Although each individual procedure has shown clinical benefits, the purpose of combining these techniques is to achieve a synergetic effect in pain relief and to restore function so joint arthroplasty can be delayed or in some cases even avoided.
Previous literature has demonstrated inconsistent improvement in patient satisfaction as well as postoperative motion after primarily addressing GHOA with arthroscopic procedures.16,17,29 When focusing on chondral defects, Kerr and McCarty15 have shown that patients treated with arthroscopic glenohumeral debridement, microfracture, and biceps tenotomy had no differences in clinical outcome depending on the grade of lesion; however, they reported favorable outcomes in patients with unipolar defects when compared to patients with bipolar chondral defects. Furthermore, patients with less-advanced GHOA at time of arthroscopic management may improve more with arthroscopic intervention. Furthermore, Millett et al have noted an association between inferior humeral head osteophytes and teres minor fatty infiltration in 91 patients who were retrospectively reviewed.24 A correlation between size of the inferior humeral head osteophytes and the grade of fatty infiltration in the teres minor, with larger osteophytes associated with more fat infiltration, was observed.
Patients presenting with anterior shoulder pain and osteoarthritis may have long head of the biceps tendon pathology with tenosynovitis, pulley lesions with an unstable tendon, and fraying. The gold standard to address these pathologies in patients with GHOA is either tenodesis or tenotomy of the tendon. Both procedures improve patient outcomes postoperatively.30 However, a greater rate of distalization of the muscle belly—so-called “Popeye” deformity—when tenotomy is performed has been reported. Some patients do complain of subjective and functional differences between tenodesis and tenotomy; therefore, in young athletes with early GHOA, we prefer biceps tenodesis because of concerns about cramping and cosmesis following tenotomy. Some studies suggest that patients undergoing tenotomy will have fatigue, discomfort, and slightly reduced elbow supination strength when compared to tenodesis.31,32
Millett and colleagues reported the surgical outcomes of 30 shoulders with symptomatic GHOA in young, active patients with advanced shoulder GHOA.33 Of those 30 shoulders, 24 were still functioning at final follow-up, whereas 6 progressed to arthroplasty at a mean of 1.9 years. They found that patients with a joint space on radiographs of less than 2 mm were more likely to undergo shoulder arthroplasty. For shoulders that did not fail, the minimum follow-up was 2 years and the mean follow-up was 2.6 years. The overall improvement in this patient cohort in the American Shoulder and Elbow Surgeons (ASES) score was from 58 points to 83 points. The postoperative patient satisfaction was a median of 9. The authors presented a survivorship rate of 92% at 1 year and 85% at 2 years postoperatively. In the most recent study performed by Mitchell et al,34 49 shoulders that underwent a CAM procedure were evaluated with a minimum follow-up of 5 years. The mean age at time of surgery was 52 years in this patient population. All patients were recreational athletes with 7 former collegiate or professional athletes. Thirty-seven of the 49 survived 5 years or longer. Twelve out of 49 shoulders (26%) progressed to a total shoulder arthroplasty at a mean of 2.6 years postoperatively. In this cohort, the authors found a survivorship rate of 76% at 5 years. The mean ASES score was stable over time at 85 points at final follow-up for those shoulders that did not fail. Patient satisfaction was also stable over time with a median of 9 of possible 10 points. An analysis of preoperative factors that predicted failure of treatment showed that patients who failed had significantly less joint space than those who succeeded (1.3 mm vs 2.6 mm). Higher Kellgren-Lawrence grades for GHOA and age older than 50 years were also associated with failure. Shoulders with Walch type B2 and type C glenoid deformities were also significantly more likely to fail than glenoid types A1, A2, and B1.
Hemiarthroplasty has been widely used with younger patients while avoiding the risks of glenoid implant loosening and polyethylene wear. Nevertheless, mid- and long-term studies have shown that even in patients who were initially pain free, recurrent symptoms with loss of motion and pain caused by progression of glenoid erosion occur over time.35–37
Interposition arthroplasty is a chosen biologic graft, secured to the glenoid surface, with or without a prosthetic hemiarthroplasty to treat young patients with advanced GHOA. The goal of interposition arthroplasty is to delay or even avoid a total shoulder arthroplasty and the associated complications seen in young and high-demand patients: early wear and loosening of the glenoid component.