Posterior wall fractures of the acetabulum: characteristics, management, prognosis.

A consecutive series of 60 fractures of the posterior wall of the acetabulum, treated operatively in a Level I Trauma center, is reviewed retrospectively. Characteristics of the lesion, type of treatment, early and late postoperative complications and two-year functional results were recorded. In 27 patients (45%), additional damage to the cartilage of the acetabular cavity such as subchondral impaction, free articular fragments or separation of the posterior wall into several pieces was present. Seven patients (11.6%) showed preoperative neurological deficit. All fractures were treated with open reduction and internal fixation through a Kocher-Langenbeck approach. Secondary nerve damage was present in 8.3%. Early secondary surgery was necessary in 8.3%. During the first two years, additional surgery was performed in 7 patients (15.2%). The rate of periarticular ossifications was 26.1%. The rate of excellent and good results was 69.5%. The posterior wall fracture of the acetabulum is a more complex injury than generally is accepted. A large variety of articular lesions with varying degree of complexity is collected in this fracture type. Even in experienced hands, excellent and good long-term results will not exceed 75%. Poor results are due to suboptimal reconstruction of the posterior wall, partial osteonecrosis and/or complications of the Kocher-Langenbeck approach.