Shoulder replacement, or shoulder arthroplasty, is a procedure commonly performed to alleviate severe pain and restore movement lost due to conditions like advanced arthritis or significant trauma. This surgery involves replacing the damaged joint surfaces with artificial components made of metal and plastic. While it is generally a successful intervention that improves a patient’s quality of life, it is a major operation that carries inherent medical risks and requires a substantial commitment to recovery. Understanding the potential downsides of this procedure is important for anyone considering an artificial shoulder joint.
Acute Risks During and Immediately After Surgery
Any major surgical procedure carries the risk of a serious medical complication, and shoulder replacement is no exception. A serious concern specific to the shoulder is nerve injury, which occurs in an estimated 1% to 4% of anatomic total shoulder replacements and a higher rate of 2% to 8% for reverse total shoulder arthroplasty. The axillary nerve and the brachial plexus are the most commonly affected structures, often due to stretching during the operation. While most nerve injuries result in temporary weakness or numbness that resolves over several months, a small percentage can lead to a long-lasting deficit.
Infection presents another serious complication that can occur superficially in the wound or deeply around the prosthetic components. Deep-seated infections are difficult to treat and may necessitate multiple surgeries or even removal of the implant to resolve. General surgical risks include adverse reactions to anesthesia, which can range from minor issues to severe breathing complications.
Though less common than with lower extremity procedures, blood clots, such as deep vein thrombosis (DVT) and pulmonary embolism (PE), remain a possibility following shoulder surgery. The estimated incidence of blood clots in the arm following shoulder replacement is low, affecting about 1 in 200 patients. Patients must be screened and managed for these risks both before and after the procedure.
The Extended Burden of Rehabilitation
The commitment required for post-operative rehabilitation is often a significant downside for many patients. Unlike hip or knee replacement, where movement is encouraged almost immediately, the shoulder requires a period of strict immobilization to allow the soft tissues to heal. This typically means wearing a sling continuously for four to six weeks, an initial phase that severely restricts the use of the arm for everyday tasks.
During this time, simple acts like sleeping comfortably, driving, dressing, and bathing become challenging, often requiring temporary reliance on family or caregivers. Physical therapy begins almost immediately, starting with gentle, passive range-of-motion exercises where the therapist or the patient’s opposite arm moves the operative arm. The gradual progression to active movement and strengthening is slow, demanding consistent attendance at therapy sessions and diligent performance of home exercises.
Achieving the maximum functional benefit from the replacement usually takes six months to a full year. The intensity of this extended recovery process, coupled with the initial limitations and discomfort, can be taxing on a person’s psychological and emotional well-being. A successful outcome is highly dependent on the patient’s commitment to this demanding, year-long rehabilitation process.
Limits on Long-Term Function and Activity
Even when a shoulder replacement is considered successful, it does not fully restore the shoulder to its original, healthy state, and permanent restrictions are necessary to protect the artificial joint. Patients must accept that the new joint will have limitations on its ultimate range of motion. While movement will be greatly improved from the pre-operative condition, full, unrestricted motion is rarely achieved, especially for movements like reaching directly overhead or reaching behind the back.
The most notable permanent limitation is the restriction on lifting heavy objects and engaging in high-impact activities. Surgeons generally advise patients not to lift anything heavier than 20 to 30 pounds with the operative arm on a regular basis. This restriction is necessary to prevent premature wear on the prosthetic components and to reduce the risk of implant loosening.
Furthermore, activities involving repetitive, strenuous motion, such as heavy weightlifting, chopping wood, or high-contact sports, must be avoided permanently. These modifications to activity levels are a condition of ensuring the longevity of the artificial joint. Patients with physically demanding jobs must often modify their work tasks or change roles entirely to accommodate these long-term restrictions.
Device Wear, Loosening, and Revision Surgery
The prosthetic joint is a mechanical device, and a significant downside is that it is not designed to last indefinitely. The lifespan of a shoulder replacement is finite, and all implants will eventually fail due to mechanical wear or loosening. Current data indicates that approximately 90% of total shoulder replacements are still functioning well at ten years, and about 80% survive for twenty years.
The most common long-term failure mechanism is aseptic loosening, where the bond between the implant and the bone weakens over time without an infection. This is often accelerated by the wear of the polyethylene plastic liner, which generates microscopic debris that contributes to bone loss around the implant. Other mechanical failures include instability, which can lead to the joint dislocating, and periprosthetic fracture around the implant.
When the prosthetic joint fails, revision surgery is necessary to replace the worn or loose components. Revision surgeries are technically more demanding than the initial replacement, carry higher risks of complication, and typically result in a less predictable functional outcome. For younger patients, the near certainty of needing one or more complex revision procedures over their lifetime is a substantial factor to consider.