With more and more older adults having a total shoulder replacement (TSR), it’s expected that more patients will experience unexpected problems. Persistent pain, restricted range of motion, and loss of function can mean a second or revision surgery. An unstable shoulder (one that partially or fully dislocates) will also require further treatment.
Some of the decision about whether (and how) to treat may depend on the underlying cause for the implant failure. For example, soft tissue problems such as rotator cuff deficiency or capsular adhesions are more difficult to treat than problems with the bone. Infection is another challenging problem that may require removing and replacing some or all of the implant.
Before a second surgery is considered, the surgeon will re-evaluate the patient closely. The reason for the first shoulder replacement (e.g., inflammation, trauma, rotator cuff rupture) is important. The patient’s cognitive and psychologic state are important. Someone who has dementia or Alzheimer’s and cannot follow postoperative directions may not be a good candidate for another surgery even when the shoulder is unstable or painful.
The surgeon’s examination includes assessment of muscle strength, shoulder motion, and nerve function. Clinical tests and imaging studies help pinpoint whether the problem is coming from the prosthetic (implant), soft-tissue structures, bone, or all three. X-rays may not be enough so that more advanced imaging such as MRIs or CT scans could be needed. Basic lab tests are also done to look for any sign of infection.
When after all these tests the cause of the problem is still unknown, then arthroscopic examination may be helpful. Inserting a scope with a tiny TV camera on the end into the joint gives the surgeon a direct view of the shoulder. Loosening of any part of the implant will be seen as well as infection, instability, or component loosening or wear.
Most surgeons use a flowchart called an algorithm to help when deciding what’s wrong and what to do about it. At the top of the chart is “painful arthroplasty.” Infection workup is first and the chart flows according to whether the test results are positive or negative. If infection is positive, then a determination is made whether this is acute (early onset) or chronic (long-standing problem). Treatment is determined on the basis of this classification.
On the negative side (no infection present), the surgeon must evaluate stiffness versus instability/weakness. In either case, physical therapy is often the next step in treatment with subsequent treatment based on whether there is improvement or not. If the problem cannot be corrected with rehabilitation, then a revision surgery may be necessary.
The decision to perform a revision procedure is not the final decision the surgeon must make. There are many different possibilities including removing just one component of the implant and replacing it, removing the entire implant and replacing it with a reverse shoulder arthroplasty, correction of the soft tissue failures, or perhaps even a do-nothing policy.
Soft tissue deficiencies pose additional challenges depending on which tendon or muscle is torn, worn, or weak and whether or not there are other soft tissue imbalances. In all cases, patients facing a second or revision surgery will be warned that the procedure may not clear up all deficiencies. For example, they may experience pain relief but may not gain any more shoulder motion.
For best results, patients should be evaluated carefully and selected for revision surgery based on the decision-making algorithm described. Patients considering revision surgery may want to ask their surgeon to walk them through the decision-making process used to come up with this recommendation. And your mother should be prepared that a second surgery may help with pain relief but does not always restore motion or full function.