Abstract
Bipolar hemiarthroplasty systems are currently widely used for the treatment of femoral neck fractures. A dislocation of the inner head in bipolar hip prosthesis with a self-centering system is a rare complication. Here we describe disassembly of a bipolar prosthesis in an elderly patient. An 86-year-old woman suffered a fall, and dislocated the inner head with a self-centering bipolar hip prosthesis. No structural damage was detected in the implant at re-exploration, and no technical difficulty was encountered during either procedure. The mechanism of disassembly was considered to have been impingement between the outer head and the acetabulum while the hip was forced into flexion, adduction, and internal rotation.
