Shoulder replacement surgery (shoulder arthroplasty) alleviates chronic pain and restores function to a severely damaged shoulder joint. This procedure replaces the damaged “ball and socket” with artificial components, typically made of metal and plastic. The success of this operation relies heavily on the post-operative rehabilitation process. The timing and execution of physical therapy must be carefully managed to protect the healing tissues while gradually regaining mobility. This structured rehabilitation journey begins immediately after the operation.
Immediate Post-Surgical Immobilization
The period immediately following shoulder replacement requires protection and controlled immobilization of the joint. Patients are typically fitted with a specialized sling or brace that must be worn continuously for the first several weeks, only removing it for prescribed exercises or personal hygiene. The sling’s primary purpose is to protect the surgical site and the soft tissues repaired during the operation. Allowing the shoulder to move freely too soon can disrupt the healing of tendons and muscles, risking a serious complication.
While the shoulder joint is immobilized, movement in the hand, wrist, and elbow is encouraged. Patients are instructed to perform small, gentle range-of-motion exercises for these distal joints several times a day. These movements help prevent stiffness in the arm and maintain healthy circulation, supporting the overall healing process. Movement of the shoulder joint is strictly limited to very specific, gentle motions prescribed by the surgeon until formal physical therapy begins.
This initial phase typically lasts from the first day through the second or fourth week. This is a time for soft tissues to begin healing and for the bone to start growing into the implant. Patients must avoid any action that uses the shoulder muscles to lift, push, or pull the arm, including using the arm to push up from a chair or bed. These precautions are necessary to ensure the delicate surgical repairs are not stressed before they gain sufficient strength.
Factors Determining the Start of Formal Physical Therapy
The question of when formal physical therapy begins depends almost entirely on the specific type of shoulder replacement performed. The two primary types—Total Shoulder Arthroplasty (TSA) and Reverse Total Shoulder Arthroplasty (RTSA)—have fundamentally different rehabilitation protocols due to their distinct biomechanics and soft tissue involvement. The surgeon’s specific protocol, based on the method used to access the joint and the condition of the patient’s tissues, is the ultimate determinant.
In a standard TSA, the surgeon typically repairs the subscapularis tendon, one of the four rotator cuff muscles, which is temporarily detached to gain access to the joint. Because the success of a standard TSA relies on a healed, functioning rotator cuff, the rehabilitation must protect this repair. Therefore, formal Passive Range of Motion (PROM) exercises often begin relatively early, sometimes as soon as two to three weeks after surgery, to prevent stiffness while still protecting the tendon.
Reverse Total Shoulder Arthroplasty (RTSA)
The RTSA procedure is typically performed when the patient has an irreparable or severely damaged rotator cuff. This procedure reverses the ball and socket, repositioning the center of rotation to rely on the large deltoid muscle for movement, rather than the compromised rotator cuff. To allow the deltoid to heal and adapt to its new role without undue stress, the start of formal physical therapy is often delayed.
For RTSA, the initial phase of formal therapy is commonly delayed until four to six weeks post-operation. This delay is a protective measure to ensure the fixation and initial soft tissue healing are secure. It prevents the new, deltoid-driven mechanism from being overloaded too early, which could risk complications such as dislocation. The individualized plan from the surgical team must be followed precisely.
Focus of the Initial Rehabilitation Phase
Once the surgeon gives clearance for the initial rehabilitation phase, the focus is strictly on regaining mobility without applying stress to the healing tissues. This phase, which generally spans the first four to eight weeks of formal therapy, is dominated by Passive Range of Motion (PROM) exercises. During PROM, the physical therapist or the patient’s non-operative arm moves the operated arm, ensuring the shoulder muscles remain completely relaxed and do not contract.
The therapist guides the arm through controlled motions, such as gentle forward elevation and external rotation, while adhering to specific angular limits set by the surgeon. The goal is to restore the basic range of movement and prevent the formation of stiff scar tissue, which can severely limit long-term function. This early mobility is achieved without the patient actively engaging their shoulder muscles, thereby protecting the tendons and muscle attachments from excessive force.
A common component of this early program is the pendulum exercise. The patient leans over and allows the operated arm to hang freely, swinging it in small circles or front-to-back. These exercises use gravity to gently move the joint, promoting fluid circulation and reducing stiffness without requiring muscular effort from the shoulder. Strengthening exercises are completely avoided during this time, as they would place harmful strain on the recently repaired structures.