Final answer:
A common complication after an isolated poly exchange for concentric wear and osteolysis is instability, which increases the risk of dislocation. Other factors contributing to instability include insufficient soft-tissue tension and component misalignment. Repeat osteolysis can also occur with the new polyethylene insert.
Step-by-step explanation:
The question pertains to a complication that is common after an isolated polyethylene (poly) exchange in the case of concentric wear and osteolysis following total joint arthroplasty. One of the most common complications after such a procedure is instability, leading to an increased risk of dislocation. Instability can occur due to several factors, including insufficient soft-tissue tension, misalignment of the components, and wear of the new polyethylene insert. Ensuring proper component positioning and soft-tissue balancing during surgery can help mitigate this risk. Additionally, repeat osteolysis can also be a concern, as the new polyethylene may still trigger a biological response that leads to bone resorption.