While there are many possible definitions of a failed shoulder arthroplasty, we prefer to view it from the perspective of the patient: if the result did not measure up to expectations, it was unsatisfactory in the eyes of the patient. We have previously reported two investigations of the factors associated with unsatisfactory shoulder arthroplasties.
A failed arthroplasty is not the same as a complication. Postoperative restriction of range of motion may make the surgery a failure from the standpoint of the patient. A postoperative hematoma is a complication, but the result may still be a success from the standpoint of the patient. It is well recognized that the patient's view on what is a poor result often differs from the view of the surgeon.
It is important to clarify expectations before surgery so that the patient understands the possibility of post operative pain, stiffness, weakness and inability to perform the desired activities. We point out that shoulder arthroplasty does not "replace" the joint in the same way that we replace a burned out lightbulb; in the latter case the new is as good as the original, in the former case the new is never as good as the original normal shoulder. While we think of arthritis as a condition of the joint surface, it also affects the structure and function of the surrounding capsule, muscles and tendons. We also point out that, in contrast to an appendectomy (where the patient has only a small role in determining the result), in a shoulder arthroplasty, the patient's rehabilitation effort has a critical effect on the success of the procedure.
Each failure provides us with the opportunity to learn how to improve our patient selection and care so that we can comply with Codman's admonition to find out why the result was unsatisfactory, or in his words "the End Result Idea, which was merely the common-sense notion that every hospital should follow every patient it treats, long enough to determine whether or not the treatment has been successful, and then to inquire `if not, why not?'" This is the case for all shoulder arthroplasties, for which the revision rate is on the rise, and especially the case for relatively new procedures, such as the reverse total shoulder for which revision rates may be as high as one in six cases and which now seems to account for upwards of 50% of the shoulder arthroplasties.
We need to strive to identify the factors associated with failure of shoulder arthroplasty and group them in terms of the 4Ps: the shoulder problem, the patient with the shoulder problem, the procedure and the physician performing the procedure.
