Isolated Head and Liner Exchange in Revision Hip Arthroplasty.

As the number of primary total hip arthroplasties increases, so does the burden of revision procedures. The decision to revise well-fixed components in the setting of polyethylene wear and osteolysis is controversial. Modular head and liner exchange offers the advantages of reduced invasiveness, faster recovery, and bone preservation. These advantages come at the expense of higher rates of revision surgery for instability. Using the native locking mechanism for securing the new liner is preferred; however, cementing a liner into a well-fixed acetabular component is a practical alternative. The use of bone allograft or bone graft substitute for areas of osteolysis is controversial. In the setting of osteolysis, outcomes associated with the use of highly cross-linked polyethylene liners have been better than those associated with the use of conventional polyethylene; therefore, thinner liners and larger femoral heads can be used and reduce the risk of instability.