left shoulder athroplasty

For your convenience I'm describing the whole detail of Left shoulder arthroplasty. Have a look over that.

Types of arthroplasty:

There are various types of arhroplasties but basically all work on the ball and socket principle.

Varion Silastic Cup:

This is an interpositional arthroplasty in which a silastic cup is placed over the humeral head, separating it from the glenoid. It is a simple operation and improves motion by removing the pain. Head must be placed concentrically, for if it is deformed, the silastic cup often fragments and leads to failure of arthroplasty.

Neer Total shoulder ll:

This is an arthroplasty which has a metal alloyed head at the stem, cemented inside the medullary cavity of the humerus. The glenoid component is high density polyethylene with a metal backing fixed to the neck of glenoid. It can give a good range of movement when the rotator cuff is intact. When the mobility is attenuated, such as RA, the increased range of rotation still significantly improves function of the limb. The glenoid component is usually cemented in place although biological or screw fixation has also been used. The humeral stem component is fit tightly (a press fit) into the intramedullary canal of the humerus for fixation but may need to be cemented in place in patients with severe osteoporosis.

The designs of total shoulder replacements, ranging from unconstrained to constrained, provide varying amounts of mobility and stability of the GH joint.

The unconstrained design, also referred to as a resurfacing replacement, provides the greatest freedom of movement but is indicated only when the rotator cuff and deltoid mechanisms are intact or can be adequately repaired to provide dynamic stability to the glenohumeral joint.

Semi constrained and constrained replacements have more stability built into their designs but are indicated Only when the rotator cuff functions insufficiently.

Loosening or excessive wear of the polyethylene glenoid component are the most common long-term complications after TSR. Although loosening of the humeral component can occur, the major concern after hemiarthroplasty is premature wear of the articular cartilage of the glenoid fossa.

Hemiarthroplasty:

A hemiarthroplasty involves only the replacement of the head and neck of the humerus with a metal stemmed prosthesis.

TSR Versus Hemiarthroplasty:

Controversy exists over the specific criteria for selection of TSR versus hemiarthroplasty, but in general, it depends on the etiology and severity of the joint deterioration and soft tissue dysfunction. Patients with primary OA usually have loss or thinning or the articular cartilage of the head of the humerus and the posterior portion of the glenoid fossa, but the rotator cuff is intact in approximately 90% of these patients. Selection of
a resurfacing TSR usually yields the best results for shoulders with these characteristics. As many as 30 to 40% of patients with advanced RA of the glenohumeral joint have rotator cuff insufficiency, and many have bony erosion of the glenoid. These characteristics lend themselves well to a TSR with bone grafting at the glenoid to improve prosthetic fixation and a repair of the rotator cuff. If an effective cuff repair cannot be achieved, then a more constrained design of TSR is selected by some surgeons.

A hemiarthroplasty is often used when the articular surface and underlying bone of the head of the humerus have deteriorated but the glenoid fossa is reasonably intact. (This is referred to as osteonecrosis of the head of the humerus.) Patients with severe pain and loss of function as the result of massive, irreparable cuff tears may also be candidates for hemiarthroplasty. Some surgeons prefer a hemiarthroplasty to a TSR for patients with RA in whom joint destruction is coupled with longstanding cuff insufficiency or contractures that cannot be resolved effectively. (This is often referred to as cuff tear arthropathy.). These problems may lead to superior migration of the head of the humerus within the glenoid fossa. If the glenoid is resurfaced under these conditions, the superior migration creates an incongruous articulation that accentuates the risk of loosening and premature wear of the glenoid implant.

Operative Procedures:

The patient is placed in a semi reclining position. The procedure involves an anterior approach with a deltopectoral incision that extends from the AC joint to the deltoid insertion. The pectoralis major is released, an anterior capsulotomy is performed, the
GH joint is dislocated, a humeral osteotomy is performed, and the head of the humerus is removed. Deltoid reflection usually is not required. The glenoid fossa is also débrided. Concomitant procedures that may be performed include:

Repair of a deficient rotator cuff

Anterior acromioplasty for a history of impingement syndrome

Subscapularis lengthening for a significant internal rotation contracture

Bone graft of the glenoid if bone stock is insufficient for fixation of the glenoid implant
After implantation of the prosthetic components and repair of soft tissues, the shoulder is passively moved through all planes of motion to visually evaluate the stability of the prosthetic joint and the integrity of the repaired soft tissues. This determines the anatomic ROM possible and how aggressive the postoperative program can be.

Postoperative Management:

Patients with an intact rotator cuff mechanism prior to shoulder arthroplasty are most likely to achieve significant functional improvements postoperatively. Coexisting rotator cuff deficiency that cannot be adequately repaired by a concomitant procedure necessitates a more cautious postoperative treatment plan that emphasizes joint stability over functional mobility.

Immobilization and post operative Positioning

At the close of the surgical procedure the operated arm is placed in some type of shoulder immobilizer, usually a sling and swathe or Velpeau dressing, to protect reattached and repaired soft tissues.

Positioning After Shoulder Arthroplasty: Maximum Protection Phase

Supine

Arm immobilized in sling-swathe dressing
Elbow flexed to 90 degrees
Forearm and hand resting on abdomen
Arm at patient’s side in slight abduction and supported on a folded blanket or pillow
Forward flexion (10–20 degrees) and internal rotation of the shoulder
Head of bed elevated about 30 degrees

Sitting

Arm supported in sling or resting in the above position on a pillow in the patient’s lap

With Tenous Rotator Cuff Repair

Shoulder positioned in abduction splint or airplane splint for an extended period of time

Exercises:

For convenience the rehabilitation phase has been divided in to three phases which are:

Exercise: Maximum Protection Phase

Exercise: Moderate Protection/Controlled Motion Phase

Exercise: Minimum Protection/Return to Functional Activity Phase

Exercise: Maximum Protection Phase:

This phase of rehabilitation, which emphasizes pain control protected motion and prevention of atrophy, may extend from 2 to 3 weeks or, if the patient has a tenuous rotator cuff, as long as 6 weeks.

Maintain mobility of adjacent joints.

While the shoulder is immobilized, encourage the patient to keep the shoulder, neck, and upper trunk musculature as relaxed as possible. Use gentle massage to these areas, and have the patient perform active movements of the neck and scapula to maintain normal motion and minimize muscle guarding and spasm. Active ROM of the hand, wrist, and elbow when the arm can be removed from the sling.

Regain shoulder mobility.

Initiate passive or therapist-assisted shoulder motions within a protected range and with the patient lying supine begun the day after surgery or no later than 48 hours postoperatively. Emphasize forward elevation of the arm in the plane of the scapula for patient comfort. Perform abduction and limited internal and external rotation within a protected range with the elbow flexed and the arm on a folded towel slightly away from
the side of the trunk (internal rotation and external rotation to 30 degree, with arm by the side). Abduction should always be with the arm in neutral as the combined movement of abduction and lateral rotation should not be attempted until 6 week post operatively. All movements of shoulder are exercised except for lateral rotation. This movement is left until 6 weeks pot operatively, when all the soft tissues have healed and thus will prevent dislocation. In addition, some surgeons prescribe the immediate use of a CPM unit for passive elevation of the arm.

Self-assisted shoulder ROM performed in supine. Incorporate reaching movements (to the nose, forehead, or over the head as comfort allows) to simulate functional movements. Initially, teach the patient to assist with the sound hand and later with a wand or dowel rod.

Pendulum exercises without a hand-held weight and with the elbow flexed (for a shorter moment arm). Encourage the patient to periodically remove the sling and gently swing the arm during ambulation.

Active-assistive shoulder ROM in sitting or standing with a wand, by performing “gear shift” exercises or use of an overhead rope pulley system to lessen the weight of the arm.
Add horizontal abduction and adduction to ROM exercises. Remind the patient to maintain an erect trunk when performing assisted shoulder motions while seated or standing. Incorporate “shoulder rolls” by elevating, adducting, and then relaxing the scapulae to reinforce an erect posture of the trunk.

Minimize muscle atrophy.

Gentle muscle-setting of shoulder musculature with the elbow flexed. Teach these exercises in preparation for discharge (usually 3–4 days postoperatively) by having the patient practice isometrically contracting the muscles of the sound shoulder. Postpone setting exercises of the operated shoulder until about 7 days postoperatively in the home exercise program.

Scapular stabilization exercises in nonweightbearing positions. Target the serratus anterior and trapezius muscles.

Precautions for Maximum Protection Phase of Rehabilitation After Shoulder Arthroplasty

Exercise

Begin exercises gradually and within a protected ROM.

Implement short but frequent exercise sessions (four to five per day).

Keep repetitions low and intensity gentle.

Progress exercises more slowly in patients with a severely damaged and repaired rotator cuff mechanism.

After a repair of the supraspinatus or deltoid mechanism, avoid active antigravity abduction until the patient can initiate the movement without first shrugging the shoulder.

If the subscapularis has been repaired or divided for lengthening, perform external rotation with the arm at the side and only to neutral.

During passive or assisted shoulder rotation with the patient lying supine, position the humerus slightly anterior to the midline of the body (by placing the arm on a folded towel) to avoid excessive stress to the anterior capsule and suture line.

In sitting or standing, avoid excessive thoracic kyphosis during overhead reaching exercises. Emphasize spinal extension and scapular retraction.

If an overhead rope-pulley system is used for assisted elevation of the arm, initially have the patient face the doorway and pulley apparatus so that shoulder elevation only occurs within a protected range.

ADL

Avoid weight bearing on the operated extremity, such as pushing with the arm during transfers or when moving in bed, especially the first week after surgery.
Avoid lifting heavy objects.

Support the arm in a sling during extended periods of standing or walking.

Wear the sling while sleeping.

Exercise: Moderate Protection/Controlled Motion Phase

This phase of rehabilitation places an emphasis on moving toward active (unassisted) control of the shoulder while continuing to increase shoulder mobility.

If the rotator cuff is intact, these exercises in this phase may begin as easily as 2 to 3 weeks postoperatively; if the cuff repair is tenuous, these exercises sometimes are not initiated for at least 6 weeks after surgery.

The patient should now have discarded the sling completely during the day and should be progressing from assisted active to active movement. The physiotherapist will be showing appropriate ways to do this.

Active external rotation can be progressed beyond 30 degree but stretching should still be avaoided.

Re-establish mobility and control of shoulder Motions.

Transition from assisted to active ROM in all anatomic and diagonal planes of motion.

Wall-climbing exercises, emphasizing overhead reaching.

Addition of wand exercises behind the back to emphasize shoulder extension and internal rotation as well as scapular winging and tipping (necessary for reaching behind the back).

Use of active ROM in dressing and grooming.

Improve strength, endurance and stability of the shoulder girdle.

Scapular stabilization (alternating isometrics and rhythmic stabilization) exercises in a variety of positions combined with minimal to moderate weight bearing; light weight bearing during functional activities.

Continuation of isometric exercise of shoulder musculature against gradually increasing resistance at multiple points in the ROM.

Dynamic strengthening of the scapula and shoulder musculature (from 0–90 degrees) using light weights or elastic resistance. Begin in the supine position to support and stabilize the scapula.
Progress to the sitting position.

Upper extremity ergometry with the UBE or a portable reciprocal exerciser on a table. Emphasize progressive repetitions to increase muscular endurance.

Exercise: Minimum Protection/Return to Functional Activity Phase

The final phase of rehabilitation after shoulder arthroplasty usually begins no earlier than 6 weeks postoperatively (with an intact rotator cuff) or considerably later if the rotator cuff mechanism is deficient.

To advance to this phase of rehabilitation the following criteria should be met:

(1) pain-free, active shoulder ROM through functional ranges and

(2) Greater than a Fair (3/5) grade of strength of shoulder musculature. To return to use of the involved arm for light ADL and modified recreational activities, 85% active ROM and a muscle strength grade of at least Good (4/5) should be achieved.

There is a continued effort to restore functional ROM during this final phase of rehabilitation. It is useful for the therapist to recheck the patient and possibly modify the exercise program during this phase. For optimal results, the home exercise program may need to be continued for at least 6 months to a year.

Continue to improve mobility.

End-range, therapist-assisted, or self-stretching

Grade III joint mobilization and self-mobilization, if appropriate

Continue to improve strength, stability, and endurance of the shoulder.

Low-load, high-repetition PRE of shoulder musculature in anatomic and diagonal planes and in patterns of movement that replicate functional tasks throughout the available ROM. Position the patient in gravity-resisted positions.

Increased weight bearing through the upper extremity during functional activities.

Use of the involved upper extremity for light lifting, carrying, pushing, or pulling activities against increasing loads.

Use of the involved upper extremity for modified recreational or sport-related activities.

Outcomes

Almost all patients report a total relief of a substantial decrease in shoulder pain, as well as an improvement in functional use of the arm. If the rotator cuff and deltoid muscles are functioning well, a patient can expect to regain active ROM necessary for most functional activities within a year after surgery. Overall, patients with OA show greater improvement in ROM (forward flexion) than patients with RA. Both groups report similar improvement in pain relief and functional status. It is usually necessary to modify activities of daily living as well as work-related and recreational activities after shoulder arthroplasty.

Heavy lifting and high-impact activities should be avoided to minimize the potential for postoperative wear and tear or loosening of the prosthetic components.

References:

1-Therapeutic Exercises- Foundation and Techniques By Carolyn Kisner, MS, PT& Lynn Allen Colby, MS, PT Fourth Edition.

2-Tidy’s Physiotherapy by Stuart Porter 13th Edition.

3- Cash’s textbook of Orthopaedic and Rheumatology for Physiotherapists by Marian E. Tidswell Second Edition.