Abstract
Articular cartilage pathology in the shoulder can present in many scenarios. The most common is some degree of osteoarthrosis or chondromalacia. The less common scenarios are avascular necrosis, rheumatoid arthritis, chondrolysis, and osteochondromatosis. The current arthroscopic treatment of these conditions is limited, with little scientific evidence to guide orthopedic surgeons. The lesions that surgeons encounter in these conditions and may need to address surgically include chondral damage and deficiency, labral tearing, loose bodies, capsular thickening or hypertrophy, and synovitis. These findings can cause pain, stiffness, and mechanical symptoms that the surgeon tries to address. The means of addressing them usually involve débridement of abnormal synovium, capsular release, and loose body removal.
Keywords
osteoarthrosis, chondral rheumatoid arthritis, avascular necrosis, chondrolysis, loose body, capsular release, débridement
Articular cartilage pathology in the shoulder can present in many scenarios. The most common is some degree of osteoarthrosis or chondromalacia. The less common scenarios are avascular necrosis, rheumatoid arthritis, chondrolysis, and osteochondromatosis. The current arthroscopic treatment of these conditions is limited with little scientific evidence to guide orthopedic surgeons, but with increased knowledge and technology, this will inevitably change. The lesions that surgeons encounter in these conditions and may need to address surgically include chondral damage and deficiency, labral tearing, loose bodies, capsular thickening or hypertrophy, and synovitis. These findings can cause pain, stiffness, and mechanical symptoms that the surgeon tries to address ( ).
Diagnosis
The diagnosis of osteoarthrosis, rheumatoid arthritis, or avascular necrosis is made clinically with a combination of patient history, physical examination, laboratory tests, and imaging studies ( Figs. 7.1–7.3 ). There are still often situations in which cartilage lesions are unsuspected and are encountered during arthroscopic treatment for impingement, rotator cuff tear, or glenohumeral instability ( Figs. 7.4 and 7.5 ).
Nonoperative Treatment
Nonoperative treatment is largely palliative and consists of medication or injections to diminish the inflammatory response and physical therapy to maintain or improve shoulder range of motion and strength. Some alternative options such as the use of platelet rich plasma and stem cell injections have gained popularity and can be considered options. However, patients should be counseled that these interventions have no definitive proven benefit at the present time to modify the natural history of any of the conditions listed previously, and they may not improve pain relief either.
Indications for Surgery
Surgical indications vary with the underlying disease process. The main indications for surgery are pain, stiffness, and mechanical symptoms not manageable with conservative measures. Certainly, for advanced stages of avascular necrosis, rheumatoid arthritis, chondrolysis, and osteoarthritis, arthroplasty is the definitive option. However, some patients may wish to avoid these options for various reasons, including young age.
Mechanical symptoms are the most reliably improved symptoms, particularly if there is a loose body or displacing flap of cartilage. Stiffness may be improved with a capsular release, but unlike adhesive capsulitis, it is rarely restored to normal. The main issue with surgical management is that pain is not as predictably improved in most of the pathologies addressed, although it can be improved if the main component of surgery is a synovectomy, such as in rheumatoid arthritis.
Contraindications to Surgery
Contraindications to the arthroscopic treatment of arthrosis also vary with the underlying disease process. Synovectomy does not benefit a patient with articular incongruity. Core decompression cannot be expected to reverse bone collapse. Débridement of a small labrum tear will not help a patient with severe advanced osteoarthrosis. Manipulation under anesthesia is not helpful for patients with osteoarthritis.
Osteoarthritis
Osteoarthrosis is probably the most common clinical cause of glenohumeral incongruity seen in the office. The source of pain in osteoarthrosis is multifactorial and consists of joint surface irregularity, mechanical disturbances from loose or displaced labrum and chondral fragments, loose bodies, and joint contracture ( Figs. 7.6–7.9 ).
Arthroscopic lavage reportedly achieves temporary, limited pain relief owing to either the placebo effect or alterations in the chemical composition of the glenohumeral joint fluid. However, patients return to their baseline states relatively quickly, so such procedures are not advisable . If a surgeon wishes to treat a patient with glenohumeral arthrosis arthroscopically, the approach must be comprehensive and include removal of loose bodies and labrum fragments, release of soft tissue contracture, and restoration of joint surface congruity. Restoration of joint surface congruity may include débridement of glenoid and humeral head osteophyte. Unless the surgeon is capable of dealing with all these elements, an arthroscopic approach is unwarranted. The surgeon must also carefully explain that the procedure is not guaranteed to succeed, but offers a less invasive option for relief than arthroplasty.
After the administration of anesthesia, the shoulder is examined for range of motion but closed manipulation is not useful. Standard posterior and anterior portals are established. This can sometimes be difficult due to joint contracture and capsular volume loss. In order to facilitate entry, it is helpful to insert the posterior cannula and trocar first, placing the entry point more superior than normal, just inferior to the posterior acromion and about 1 cm medial to the posterolateral corner of the acromion. This more superior entry into the glenohumeral joint circumvents the need for the trocar to enter the joint between the humeral head and glenoid ( Fig. 7.10 ). A complete glenohumeral joint inspection is done, observing in particular the presence and extent of cartilage loss, labrum flap tears, loose bodies, synovitis, rotator cuff fraying or tearing, biceps pathology, and capsular contracture.
The anterior portal may also be difficult to establish, as the anterior capsule is also difficult to penetrate. It is sometimes necessary to use only the metal trocar (without the cannula) to create an entrance to the glenohumeral joint and subsequently place either a standard shaver or cautery to débride the rotator interval to allow access to the joint ( Figs. 7.11 and 7.12 ).
A complete capsular release is then initiated starting anteriorly, moving inferiorly, and finally, posteriorly. The inferior release is also completed posteriorly. Particular attention is paid to the subscapularis, as it seems critical to restore subscapularis muscle excursion. The middle glenohumeral ligament (MGHL) is adherent to the posterior (articular) surface of the subscapularis. The plane between these two structures should be identified, and the MHGL is excised. A complete “skeletonization” is done of the subscapularis, releasing adhesions posteriorly, anteriorly, and superomedially into the subcoracoid recess. This can be done with blunt dissectors, shavers, or cautery. This process of subscapularis release is often completed after an anterior superior portal is established to better view the subcoracoid recess, while instrumentation is done through the anterior or more anterior inferior portal ( Figs. 7.13–7.17 ).
