Monday, September 29, 2014

Shoulder Arthritis: The Cliff Notes for Physical Therapists and Other People

Glenohumeral Arthritis

The Cliff Notes for Physical Therapists and Other People

For the complete Shoulder Arthritis Book, click here.

I. Anatomy and mechanics – the glenohumeral joint represents a wonderful balance of mobility and stability. The socket is very shallow so that the humeral head is stabilized by concavity compression in which the cuff muscles press the ball into the socket. In the normal shoulder about 2/3rds of the motion is at the glenohumeral joint and 1/3 at the scapulothoracic joint. We are humbled by the challenge of trying to ‘fix’ this complex joint when it goes awry.

II. Definition – glenohumeral arthritis is a condition in which the articular cartilage normally covering the humeral head and glenoid is compromised. There are different types of shoulder arthritis. Usually it is not an inflammatory condition – such as rheumatoid arthritis - as the ‘-itis’ implies, but rather a degenerative, post traumatic or post surgical condition. Other diagnoses often lumped in with glenohumeral arthritis include avascular necrosis, cuff tear arthropathy, post-septic arthritis and chondrolysis from the intra-articular infusion of local anesthetics. Glenohumeral arthritis needs to be distinguished from two other common diagnoses, frozen shoulder and rotator cuff tear.

III. Presentation - glenohumeral arthritis causes loss of comfort and function of the shoulder. A practical way to assess the functional loss of an arthritic glenohumeral joint is with the Simple Shoulder Test (SST) . The SST is a valuable tool and the patient’s responses should be recorded at each visit to the therapist.

Summarizing the SST responses for over three thousand patients presenting for shoulder arthroplasty, we find the following percentages of patients able to perform each of the functions.

IV. Diagnosis – the diagnosis of glenohumeral arthritis requires a good history, examination of the active and passive ranges of motion and proper standardized x-rays. The history should elicit past trauma, prior treatment, prior shoulder surgery, systemic disease, medications (such as steroids), and involvement of other joints. The range of active and passive abduction, flexion, cross body adduction, reach up the back, external rotation at the side, and internal rotation of the abducted arm are usually diminished in glenohumeral arthritis. In performing these examinations, it is important to determine how much of the motion is humeroscapular and how much of the motion is scapulothoracic. The technique for taking the key x-rays for documenting the presence of arthritis is shown here. Here are examples of an AP view and an axillary view showing a normal joint space and the absence of bone spurs.

By contrast, an osteoarthritic glenohumeral joint often shows osteophytes, loose bodies, glenoid retroversion, glenoid biconcavity, and posterior subluxation of the humeral head on the glenoid as shown here.

See also this post that shows the x-ray characteristics of the different types of glenohumeral arthritis. One of the most difficult diagnoses to manage is chondrolysis resulting from the intra-articular infusion of local anesthetics with a pain pump. This condition is devastating because it occurs in young individuals having instability surgery, because it can completely destroy the articular cartilage, and because it is usually accompanied by soft tissue disease that results in pain and stiffness, even after joint replacement. Other challenging diagnoses are post-traumatic or post-surgical arthritis – both of which can distort the local anatomy requiring special modifications of the standard procedure that would be used for straightforward osteoarthritis. Shoulder arthroplasty for rheumatoid arthritis may be complicated by the soft bone, the fragile rotator cuff, severe bone erosion, and shoulder tightness.

V. Progression – glenohumeral osteoarthritis (the most common form in the U.S.) usually starts subtly with only minor symptoms at night or during certain activities. It then progresses at a highly variable rate – sometimes not changing from year to year, sometimes with a sudden worsening and sometimes with an up and down course over the seasons or years. On occasion the x-rays may appear much worse than the symptoms. “End stage” arthritis can leave the glenohumeral joint without any range of motion.

VI. Evaluation – as William Osler said, ‘it is as important to know what patient the disease has than what disease the patient has’. We are on the lookout for the 3 “D”s, diseases, depression, and dependency on nicotine, narcotics or alcohol, which can compromise the patient’s ability to respond to non-operative or operative management. The best prognostic factors are a healthy patient with a positive attitude and good social support. Patient selection is the principal key to successful surgery.

VII. Non-operative management – because surgery for glenohumeral arthritis is elective, patients have plenty of time to try to optimize their comfort and function with non-operative management. We focus on three areas of patient self-management: (1) avoidance of impact and heavy compressive loading, (2) range of motion – (exercises A,B,C,E,F,G and L on this post). and (3) traction exercises. We do not use glucosamine, chondroitin, cortisone injections, hyaluronic acid injections, ultrasound, or muscle stimulation. Non-steroidal anti-inflammatory medications may be useful, but caution is exerted to avoid cardiac, renal, liver, gastric and hematological complications. See also this post on non surgical management..

VIII. Surgical options – the different surgical procedures for glenohumeral arthritis are discussed in detail here. The first consideration is whether it is appropriate to consider surgical treatment at this time. . Shoulders with bad looking x-rays are not taken to the operating room if the patient doesn’t have substantial functional deficits, if the patient is not a good candidate for surgery for health or social reasons, if the patient does not wish to accept the risks of surgery, or if the surgeon is not comfortable with what needs to be done. The common forms of arthroplasty and the common conditions for which they are performed are listed below and here.

a. Hemiarthroplasty – avascular necrosis when the glenoid is intact

b. Total shoulder arthroplasty – osteoarthritis, rheumatoid arthritis, capsulorrhaphy arthropathy, post traumatic arthritis

c. Ream and run - osteoarthritis, capsulorrhaphy arthropathy, posttraumatic arthritis in patients wishing to avoid the risks and limitations associated with a prosthetic polyethylene glenoid component.

d. Cuff tear arthropathy (CTA) arthroplasty – this procedure is used for the arthritic, cuff deficient shoulder that has an intact, stabilizing coracoacromial arch.

e. Reverse total shoulder – rotator cuff tear arthropathy, pseudoparalysis, failed total shoulder arthroplasty with rotator cuff insufficiency. Patients considering this procedure are cautioned about the limited range of motion and function usually achieved with this surgery and also about the increased risk of fracture or fixation failure with falls.

Each of these procedures modifies the arthritic anatomy by removing abutting bone, and inserting smooth prosthetic joint surfaces that enable motion, stability and load transfer. Each procedure involves careful balancing of the capsule and other surrounding soft tissues. The procedure may include a biceps tenotomy or tenodesis if the long head tendon of the biceps is frayed or unstable.

The use of these different surgical options varies widely among different surgeons. This variation in use confounds the development of appropriateness criteria and the evaluation of outcomes. For example, surgeons who use the reverse total shoulder for milder disease will have better results than those who use it primarily after a salvage procedure after more conservative procedures have failed or when there is no other option.

IX. Postoperative care – the rehabilitation program after surgery depends on the details of the surgery performed, the specific findings at surgery, and the patient. In our practice we try to standardize and simplify the postoperative program for almost all arthroplasties. We use continuous passive motion while the patient is in the hospital and start assisted elevation the evening of surgery. Our goal is to have the patient be able to perform assisted elevation to at least 150 degrees by the time of discharge on the second postoperative day. Forward elevation stretches are done 5 times a day with a 2 minute hold. We do not work on external rotation range until after six weeks, allowing for solid healing of the subscapularis repair and then we only have the patient do very gentle stretching At six weeks we often add all of the exercises shown here. Gentle progressive strengthening is progressed from there, make sure that any exercise can be repeated at least 20 times. This program is modified if there are concerns about instability or the quality of the repairs. If the shoulder is stiff at six weeks, we consider a closed manipulation. After a reverse total shoulder we immobilize the arm in a sling for six weeks and then allow the patient to progress with gentle activities of daily living.

X. Complications – surgery for glenohumeral arthritis may yield unsatisfactory results or be associated with complications as shown here. These complications may include persistent pain, nerve injury, cuff or subscapularis failure, stiffness, instability, fracture, component loosening and infection.

XI. Expected outcomes – the results of glenohumeral arthroplasty are determined by the characteristics of (1) the shoulder problem, (2) the patient, (3) the procedure and (4) the team providing the care. We refer to these as the 4P s. We let patients know we cannot guarantee a specified result, but we do assure them of our best efforts to improve their shoulder’s comfort and function.

XII. The future – much hope has been placed on ‘biological resurfacing’ with interpositional grafts of cadaver meniscus or artificial materials. These however have get to yield durable results, probably because of the mortar and pestle action of the humeral head and glenoid on the interposed material. While ‘tissue-engineering’ sounds attractive, attempts to grow cartilage and implant it in a human joint have been frustrated. The most promising regenerative procedure in our view is the ream and run procedure in which the healing response of concentrically reamed glenoid bone is molded by a smooth, round humeral head prosthesis. This procedure appears to enable the glenoid to cover itself with fibrocartilage bonded to the underlying bone.

XIII. Role of the therapist – in a word, essential. Ideally the patient and therapist get to know each other before surgery, sharing the program and the plan for ongoing communication. In the hospital the therapist starts the rehab program and assures the patient is ‘on top of it’ before discharge. After discharge the therapist is available on an ongoing basis for answering questions, measuring progress, and alerting the surgeon to any deviations from the expected recovery.