| | Rehabilitation After Total Shoulder Arthroplasty: Current ConceptsSuccessful outcome of total shoulder arthroplasty depends on a well-designed and a well-executed physical therapy program. For maximal benefit, the program is usually initiated immediately after surgery and follows a logical pattern of joint mobilization followed by muscle strengthening. The process proceeds through a series of well-defined phases. The patient must see him- or herself as the active agent in the program, a concept that is enhanced by a discussion and demonstration of the therapy goals before surgery. Because of a unique understanding of the therapy requirements, the surgeon should remain intimately involved with the patient and therapist, frequently evaluating progress and outcomes of the exercises. When a well-performed surgical procedure is supplemented with a well-designed and frequently monitored therapy program, an excellent outcome of shoulder replacement should be expected. Shoulder replacement will fail without adequate rehabilitation. Only the surgeon can and must direct the rehabilitation program (C. Neer, personal communication, 1984). Total shoulder replacement may be a technical exercise in the operating room, but successful arthroplasty requires many hours of faithful attention to a well-designed and well-performed rehabilitation program that will maximize motion, strength, and ultimately patient satisfaction. Proper postarthroplasty rehabilitation must follow a logical sequence allowing for tissue healing, joint mobilization, and finally muscle strengthening. Variance from this logical progression frustrates the patient and physician. The patient must view him- or herself as the active agent in the program, not the passive recipient of another caregiver. The main goals of postarthroplasty rehabilitation are joint mobility (maximizing range of motion) and muscle strengthening—in that order. Joint mobilization is subdivided into three phases that must progress in a logical fashion. Strengthening is also divided into three phases that must be followed sequentially to allow maximal chance for return of function. When the surgeon realizes that technical expertise is responsible for only a small part of the success picture and that a well-designed and executed rehabilitation program performed by a well-trained and experienced shoulder therapist is mandatory, then a successful outcome can be realized. One other potential misconception needs to be corrected: the rehabilitation program does not begin after the surgical procedure; it begins at the preoperative visit. Preoperative Rehabilitation  The person designated to be the therapist postoperatively should see the patient before surgery to discuss and demonstrate the postoperative rehabilitation program. The best rehabilitation results do not just happen, they are caused. Therapists who are experienced in shoulder rehabilitation obtain better results than those who are not trained in this subspecialty. At the presurgical evaluation, the therapist should meet with the patient and, ideally, with the spouse or other family member who will participate in the postsurgical home care. At this time, the therapist should discuss the rehabilitation program, including its intents, purposes, and expectations. The therapist should then demonstrate the range of motion (ROM) program that will begin after joint replacement and reassure the patient that pain and stiffness will be normal and conquerable. A successful therapist is not just a mechanic who puts a joint through motion. He or she must have empathy and an ability to communicate with the patient. The best way to judge the quality of a successful relationship between a therapist and patient is if the patient looks forward to the interaction despite the fact that it may result in discomfort and pain. The therapist should not only be experienced in exercise mechanics, but also must be empathetic, sympathetic, and interactive with the patient. For rehabilitation to be a success, patients must see the therapist as a professional supporter and friend who understands their pain and apprehension. This relationship is better established preoperatively rather than after surgery when pain is most likely to be very significant. Preoperative discussions with the therapist may help answer questions and correct misunderstandings that frequently arise after surgery. Of equal importance to the therapist–patient relationship is the surgeon–therapist relationship. Preoperative communication between these caregivers is most desirable. Even when a direct surgeon–therapist relationship is not possible, the therapist should at least meet with the patient preoperatively. Furthermore, it is the surgeon’s responsibility to communicate the desired program and any necessary modifications to the therapist. Completion of a standard prescription form with the physical therapy order is inadequate if it is not supplemented with a direct conversation and explanation from the surgeon to the therapist. Postoperative Rehabilitation Until several years ago, postarthroplasty rehabilitation did not begin until several days after surgery. Much of this delay was necessitated by surgical exposures and procedures that included release of the deltoid muscle origin. To allow sufficient healing of this major motor of the shoulder, active use of the arm had to be restricted for many weeks. Concern for dislocation of the joint also led to a several-day delay in initiation of the rehabilitation program. Even today, many surgeons discharge patients from the hospital with slings or other supportive devices. The more recent trend by experienced shoulder surgeons has been to begin the therapy program very early. Dr. Charles Rockwood begins a rehabilitation program the same day as the surgery, initiating passive movement of the extremity a few hours after joint replacement. Newer techniques of surgery that allow preservation of the deltoid, proper component orientation, proper respect for myofascial sleeve tension, and modification of component design provide intrinsic joint stability, permitting safe, early rehabilitation. There will always be specific concerns and situations requiring modification and delays in certain exercises to protect soft tissues. For example, anterior capsular lengthening that may be necessitated by severe long-standing external rotation loss could require a delay in passive external rotation stretching to allow sufficient healing of the subscapularis capsule construct. This is all the more reason why the surgeon should and must direct the rehabilitation program. Only the surgeon knows the specific considerations that may alter an otherwise standard protocol. One benefit of using regional anesthesia (interscalene block) is, at the completion of surgery, while the patient is still in the operating room and before the dressing is placed, the involved shoulder can be placed through a ROM. When the patients are able to view their arm and the extent of motion allowed by the anesthesia, they appear to regain motion more quickly. They are more easily convinced that the pain spasm reflex limits their motion, rather than a true mechanical block. By learning to relax in the face of pain, the patient will usually find a dramatic improvement in motion. Unless there are unusual intraoperative problems, the rehabilitation program should begin within several days of the procedure to minimize scarring and adhesions between muscle groups. Most modern shoulder replacement systems do not depend on soft tissue structures to impart stability; hence, early protection of the joint from motion should not be necessary. Furthermore, in the contemporary surgical approach to shoulder arthroplasty, the only muscle divided is the subscapularis, and its motor function as an internal rotator is in many ways duplicated by other muscles. The author’s preference is to initiate the rehabilitation program on the first postoperative day. Patients are encouraged to use their arm to feed themselves the morning after surgery. Patients are given analgesics at least 30 min before the therapy is begun to allow time for the analgesic to reach peak effect. Also recommended is the application of moist heat to the shoulder for a minimum of 30 min before the session. Moist heat appears to be subjectively soothing to the patient; it may act as a mild analgesic and seems to diminish the perception of stiffness. Rehabilitation Program There are many published rehabilitation protocols in physical therapy and orthopedic texts.1, 2, 3, 4 The fact that there are so many published protocols is testimony to the fact that there is no best one. A practitioner should understand the principles of physical therapy to develop a program that satisfies patient needs and produces a successful result. These principles include the following: (1) initiate the rehabilitation program as early as possible; (2) allow early active motion; (3) eliminate or limit the use of supportive devices such as slings and immobilizers; and (4) maximize passive joint motion in the cardinal planes (elevation, internal rotation, and external rotation) before initiation of a strengthening program. Multiple short periods of stretching exercise are more beneficial than fewer prolonged sessions. The author prefers that patients spend no more than 5 min per session, two or three times per day in therapy. No one looks forward to pain, so prolonged exercise becomes psychologically debilitating. The stretching or mobilization portion of the rehabilitation program is designed to progressively increase the ROM available to the shoulder complex. This implies maximizing motion at the glenohumeral, scapulothoracic, acromioclavicular, and sternoclavicular joints. Mobilization is progressive and proceeds through various phases. The first phase of exercises is designed to initiate elevation and external rotation. Phase I continues until elevation is approximately 140° and external rotation 40°. The Phase II continues until elevation is approximately 160° and external rotation 60°. The Phase II stretching initiates internal rotation and shoulder level adduction. The final phase of stretching is designed to increase the range of all cardinal motions to their anatomic maximum. Phase I Stretching Phase I exercises are initiated within 24 to 48 hours of joint replacement. One half hour before therapy, heat and analgesics are administered as previously described. Pendulum Exercise The patient bends forward at the waist and supports their weight with the normal arm. Ideally the thoracic spine should be parallel to the floor. The involved arm should circle one way and then the other. In one direction, the hand should be maximally pronated while circling, and then the direction should be reversed with the hand now supinated (Fig. 1). Time spent per exercise is 30 to 60 s. Assisted Supine Elevation The patient should be placed supine without a pillow. A pillow raises the head and may tend to raise the shoulder and scapula off the table, which may adversely affect joint mobility. The therapist puts gentle traction on the humerus of the affected arm and gradually elevates the limb in the scapular plane. When the patient begins to experience pain, a gentle firm pressure is applied for only 3 to 5 s. Stretching is always by firm gentle continuous pressure and not with pulsating force. The arm is then gently assisted back down to the side. This may be repeated two or three times at each exercise session (Fig. 2). Total time per exercise is 15 to 30 s. Assisted External Rotation The patient is positioned on their back without a pillow. A folded towel is placed under the arm so that the long axis of the humerus of the affected arm is parallel to the spine. The elbow is brought 4 to 6 inches away from the side to reestablish the proper glenohumeral axis relationship. The therapist instructs the patient on how to use a dowel, or some type of stick, to push the forearm away from the side so as to rotate the humerus itself. Care must be taken to have proper orientation of the stick so that it rotates the humerus and does not merely extend the elbow. The stick itself must not be parallel to the waist but rather is maintained perpendicular to the humerus at all times. The patient, helper, and therapist should apply constant firm pressure in external rotation; pulsating force should not be used (Fig. 3A and B). Total time per exercise is 30 to 45 s. Assisted Elevation with a Pulley The pulley exercise assists patients in passive elevation of the arm (Fig. 4). Pulley placement is critically important. Ideally, the pulley itself should be at least 1 foot higher than the extended reach of the normal shoulder and hand. Furthermore, the pulley placement relative to the patient should be directly above their head or possibly even behind their head. If the pulley is too far in front of the patient, maximal elevation will be considerably less than ideal. The pulley should be above the patient’s head or slightly behind the patient to ensure that, as the affected arm is hoisted by the good arm, maximal elevation force occurs. The patient must be carefully instructed in use of the pulley, especially if the physician is concerned about early active motion if a cuff repair was part of the arthroplasty. As the affected arm is descending with the pulley, an undesirable eccentric contraction of the deltoid and supraspinatus may occur. Total time per exercise is 60 to 90 s. Assisted Abduction The patient lies supine without a pillow and uses the good arm to assist elevation of the affected arm. The fingers are intertwined as in a clasp, and the arms are brought up overhead and placed behind the neck. The elbows are then gently brought down by the side with the aid of a therapist. The elbows are actively brought together and returned to the side (Fig. 5). Total time per exercise is 30 to 60 s. Phase II Stretching At 10 to 14 days after shoulder replacement the second phase of stretching is begun. Internal rotation exercises are introduced. To further assist in maximizing these motions, the patient continues with stretching in elevation and external rotation using slightly different techniques than the Phase I program. Assisted Internal Rotation Both arms are placed behind the back, and the hand of the good arm grasps the wrist of the affected shoulder. The affected shoulder is pulled into extension while trying to keep the upper arm and forearm in the true sagittal plane. When maximal extension has been reached, the good arm pulls the wrist up the back as shown. As the elbow is flexed and the thumb comes up the back, internal rotation is increased. The higher the thumb reaches up the dorsal spine, the greater the degree of internal rotation (Fig. 6). Assisted Elevation The patient lies on a bed ideally fitted with a headboard under which the hands can easily fit as shown in the diagram. The patient then lies on his back without a pillow to keep the scapula resting comfortably on the mattress. The good arm is used to lift the affected arm overhead while arching the back to allow the hands to reach under the headboard. While still grasping the underside of the headboard, the arch in the back is slowly lowered, effectively increasing elevation of the shoulder (Fig. 7). Assisted External Rotation The patient stands in a doorway with the elbow of the affected shoulder placed against the side and flexed to 90°. Keeping the elbow tight against the side and turning the torso in place externally rotates the shoulder (Fig. 8). This exercise is useful in increasing external rotation from 40° to 60°.These Phase II exercises require no more than 3 to 4 min. They should be preceded by the Phase I program. Phase III Stretching These exercises are designed to help attain the last 20° of shoulder motion in all directions. Like the exercises described above, they should be performed twice daily. One set should be done in the morning on awakening, preferably immediately after a hot shower. The other set should be performed in the early afternoon. Assisted Elevation The patient should stand in reference to a convex corner approximately 12 to 14 inches away from the corner. The major concentration should be to keep the elbow straight and apply minimal pressure on the corner with the hand of the affected extremity. The patient slowly leans inward forcing the axilla, elbow, and wrist to lie on the corner. The patient keeps steady pressure on the axilla for several seconds as stretching occurs (Fig. 9). Assisted External Rotation The patient stands in a doorway with the forearms flat against the door jam and the humeri parallel to the floor. The patient leans forward into the open doorway to stretch the anterior capsule and assist in external rotation with the elbow in 90° abduction. The patient should keep pressure on the shoulders for approximately 5 to 10 s and should not pulse or jerk the shoulder during the exercise (Fig. 10). Assisted Internal Rotation The patient may stand as shown in the figure with their back up against a table or ledge. The affected arm is placed so that the back of the wrist lies on the table with the thumb along the midline of the spine. As the knees are flexed, the table acts as a platform to forcefully flex the elbow and increase internal rotation as the thumb is pulled up the back. The further the tip of the thumb rises along the thoracic spine, the more internal rotation is required (Fig. 11). Assisted Adduction This exercise is particularly valuable for the patient who is having difficulty sleeping. The arm is lifted up to shoulder level just below the chin. The unaffected arm pulls the affected arm up underneath the chin stretching the posterior capsule. While sleeping, if the patient rolls over on the affected side, the arm is forced into adduction. Recovery of this adduction motion tends to diminish the associated night pain. Patients are informed that they can anticipate doing each of these Phase III stretching exercises indefinitely (Fig. 12). Total time spent on Phase III stretching is 3 to 5 min. Summary of Stretching Virtually all patients begin a postarthroplasty rehabilitation program within 24 to 48 h starting with the Phase I stretching program. The program is done two to three times daily and can be completed in less than 5 min. The sessions are preceded by application of moist heat, and analgesic medication is recommended for the first several weeks. Most often the physical therapy program can be taught to the spouse, and the physical therapist observes the spouse to ascertain that the fine details of position and technique can be reproduced. The Phase I program is begun immediately after surgery, and the Phase II program is generally added at the time of suture removal 2 weeks later. The Phase III program begins anywhere from 3 to 6 weeks later depending on the progress of the earlier phases. The last phase incorporates adduction to improve sleep patterns and improve external rotation while the arm is in 90° abduction. At each follow-up, the patient is observed while doing these exercises to be certain that they have not incorporated unacceptable modifications of their own. Rarely are modifications necessary in the stretching program. Occasionally, surgical lengthening of a tight anterior capsule and shortened muscles may dictate a delay in the initiation of external rotation exercises to prevent instability. As the patient progresses through the stretching program, strengthening programs may begin. In those patients who have shoulder replacement for primary osteoarthritis, active motion is not only allowed, but is encouraged immediately after the surgical procedure, assuming the rotator cuff is of good quality. When there is good strength initially, the Phase I and Phase II strengthening programs may be unnecessary. On the other hand, when arthroplasty is performed on patients who have rheumatoid arthritis or who may have severe cuff deficiencies, then the benefits of the Phase I strengthening program become very evident. Strengthening The Phase I strengthening program is designed to gradually and progressively increase the strength of the anterior deltoid and supraspinatus while using the assistance of gravity. The Phase II program is designed to strengthen the rotator cuff and deltoid by eccentric contraction, and the Phase III program strengthens muscle for use against gravity in a concentric fashion. Phase I Strengthening These exercises are designed to begin the strengthening process of very weak muscles. Muscle strengthening is a slow process, and the patient must be persistent because it is easy to become discouraged at what may seem like very slow progress. Often times, the underlying condition that led to weak muscles is aggravated by the protection that must be imposed to allow satisfactory healing if a rotator cuff repair was required at the time of arthroplasty. Like the stretching exercises, the strengthening exercises should be performed at least twice daily every day. The patient is positioned supine without a pillow under the head (Fig. 13). The patient initially attempts to elevate the affected arm with the elbow flexed, extending the elbow as the arm comes up overhead. The arm is slowly brought down by the side in a steady rhythm as the arm descends between 90° of elevation and 0°. It is in this arc that gravity tries to accelerate arm movement. Prevention of this acceleration results in strengthening of the muscle by eccentric lengthening. The patient then rests a few moments and repeats the exercise. Ideally, the patient works toward repeating the exercise 10 times before proceeding. The unaffected arm may be used to assist in the elevation process, but the affected arm must be lowered to the side without any assistance. When this exercise can be performed, unassisted from beginning to end, for 10 repetitions twice daily, the program is advanced. A 0.5-lb weight is added to the hand and, with the patient supine, the arm is again lifted overhead and slowly brought back down by the side. When 10 repetitions can be performed without fatigue on a twice daily basis, a 1.5-lb weight is used. This process is repeated, adding 0.5-lb weight increments only when 10 repetitions are possible without fatigue. When the patient is able to perform this exercise with a 5-pound weight, the Phase II program is initiated. Phase II Strengthening Whereas the Phase I program is performed with the patient positioned supine to minimize the effect of gravity, the Phase II program uses gravity and strengthens muscles in an eccentric fashion. The muscles of the deltoid and rotator cuff are elongated under a contracting force that tends to improve their strength characteristics. The patient stands or sits and passively lifts the involved arm with the uninvolved arm to the point of maximum elevation (Fig. 14). The affected arm is then released and balanced overhead with active muscle control. The patient slowly flexes the elbow as the arm descends in the elevation plane while preventing any acceleration as the arm is lowered. When the arm is lowered down to the side, the patient rests for a few moments. Again, the uninvolved arm passively elevates the involved arm as high overhead as possible. When the arm is released, the patient actively descends without acceleration. This process is repeated 10 times, twice daily. When the patient can do this exercise 10 times without fatigue, a 0.5-lb weight is added to the hand of the involved extremity and the exercise is repeated. When it can be done 10 times, a 1.5-lb weight is held in the hand and the process is repeated; this program continues until the patient can actively descend the arm while holding 5 or 6 pounds. The incremental change in weight must be no more than 0.5 lb so that there is only a gradual increase in load. When 5 to 6 pounds can be brought down to the side without acceleration 10 times, the Phase III strengthening program begins. Phase III Strengthening Many patients who have good muscle strength before their shoulder replacement can initiate the strengthening program with this phase. This phase uses surgical tubing (Theraband, Hygenic Corp, Akron, OH) or any other type of elastic device to strengthen the deltoid and individual rotator cuff muscles. Each of the three heads of the deltoid (anterior, middle, and posterior) is isolated and strengthened separately. Similarly, the subscapularis and infraspinatus are strengthened individually. Strengthening of the anterior deltoid is performed as shown (Fig. 15). The patient’s back is placed toward the door. With the elbow flexed at 90° and the humerus in the sagittal midline of the body, the elastic element is pulled forward approximately 45°. It is held there for 5 s and slowly released. The posterior deltoid is strengthened similarly by having the patient face the door. It is important to begin with the arm in a 45° forward position to allow the posterior deltoid to pull the arm back against resistance, but never beyond the sagittal midline (Fig. 16). As the arm is pulled beyond and posterior to the sagittal midline, considerable forces are placed on the anterior capsular and subscapularis repair. Strengthening of the middle deltoid is best performed in front of a mirror to be certain that symmetry is maintained. The patient holds the elastic device in both arms and symmetrically abducts the shoulder in the coronal plane. It is not important that the angular excursion exceed 45° as shown in the figure (Fig. 17). The internal rotators are strengthened as shown (Fig 18). It is important that the elbow remain tight up against the side to ensure that only rotational forces are generated. The elbow remains flexed at 90°, and the arm is rotated inward against resistance no more than 45°. The tension is slowly released. External rotators are strengthened in a very similar fashion with the patient facing the opposite direction relative to the door handle (Fig 19). The arm is rotated out 45°, keeping the elbow tight against the side. Because the infraspinatus is the only effective external rotator, there is a frequent tendency to abduct the arm away from the side allowing the deltoid to substitute. Each of these Phase III strengthening exercises should be performed twice daily in sets of 10. After 3 months on this program, scapular muscle strengthening, including the trapezius, rhomboids, latissimus, and pectorals, begins. Depending on the patient’s age and activity level, variable intensity is given to this later set of exercises. Continuous Passive Motion Certain situations are potentially more appropriate for use of continuous passive motion. Patients who have bilateral shoulder problems may find continuous passive motion beneficial where self-assisted exercises would be difficult or impossible. Donning and doffing the apparatus is difficult and usually requires an assistant, particularly in the geriatric population. Neer5 reported his experience with continuous passive motion and found it to be marginally beneficial at most. In cuff repairs, shoulder replacements, and acromioplasty, they found that continuous passive motion resulted in earlier recovery of motion, diminished pain, and a shorter hospital stay. Continuous passive motion machines of many varieties are commercially available. Thorough knowledge of its capabilities and limitations is mandatory if a practitioner is going to use one. The author suggests an evaluation of the cost–benefit ratio and advises that their use be limited to patients in whom self-assistance is not possible. Summary Proper rehabilitation after total shoulder replacement is not just necessary, it is critical to a successful outcome. The surgeon must direct, modify, and continually evaluate the progress of the physical therapy program. Unless specific surgical concerns dictate otherwise, the formal rehabilitation program should begin no more than 48 hours after the procedure. Understand that, in the overall context of insuring success, discussion of the postoperative therapy actually begins before the incision is made. This rehabilitation program proceeds in a logical and orderly fashion beginning with joint mobilization to maximize ROM in the cardinal planes. Strengthening begins when motion allows and likewise proceeds in a stepwise fashion until maximum strength is achieved. When the principles of surgical technique are combined with the principles of rehabilitation, successful total shoulder replacement can usually be attained. References 1. 1Brems JJ. Rehabilitation following total shoulder arthroplasty. Clin Orthop Relat Res. 1994;307:70–85. 2. 2Cofield RH. Degenerative and arthritic problems of the glenohumeral joint. In: Rockwood CA, Matsen FA editor. The Shoulder. Philadelphia, PA: WB Saunders; 1990;p. 735–736. 3. 3In: Gould JA, Simons DG editor. Orthopaedics and Sports Physical Therapy. Vol 2:St Louis, MO: CV Mosby; 1985;p. 199–211. 4. 4Rockwood CA. The technique of total shoulder arthroplasty. In: Greene WB editors. AAOS Instructional Course Lectures. Vol 39:St Louis, MO: CV Mosby; 1990;p. 437–447. 5. 5Neer CS. In: Shoulder Rehabilitation: Shoulder Reconstruction. Philadelphia, PA: WB Saunders; 1990;p. 495. Department of Orthopaedic Surgery, Cleveland Clinic Foundation, Euclid, OH.  Address reprint requests to John J. Brems, MD, Cleveland Clinic Foundation, Department of Orthopaedic Surgery, 99 Northline Circle Dr., Suite 100, Euclid, OH 44119.
PII: S1045-4527(06)00066-6 doi:10.1053/j.sart.2006.11.001 © 2007 Elsevier Inc. All rights reserved. | |
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