Total hip arthroplasty (THA) is a commonly performed surgical procedure for various arthritic conditions that affect the hip joint, and it has proven to be highly effective for the relief of pain and improvement in the quality of life. Despite many recent advances in THA, dislocation continues to be a frequent complication, and the incidence of dislocation ranges from 1% to 5% in primary THAs. The literature abounds with options for the treatment of recurrent dislocation after THA. However, to the best of our knowledge, successful treatment with open reduction of a chronic proximal dislocation after THA has not been reported previously in the literature.

We report an unusual case of a chronic prosthetic dislocation that was caused by the buttonholing of a prosthetic femoral head by anterior soft tissue, which impeded reduction. A surprisingly good functional result was achieved by an open reduction and revision operation on a 56-year-old man, who had a chronic dislocation of a total hip prosthesis. 5 years after the surgery, the patient has no clinical or radiographic evidence of recurrence of dislocation of THA. We believe that a chronic irreducible dislocation may hamper operations by adhesion and scar tissues. Especially soft tissue buttonholing makes it impossible to perform a closed reduction. We restored a much higher level of function by a single operation in a short time, and made the patient to be able to ambulate with fast recovery from the surgery. Equal limb lengths were restored and no neurologic compromise occurred.

Introduction: Despite the advances in total hip arthroplasty (THA), a dislocation after THA remains a disturbing complication. Dislocation after revision hip arthroplasty has been an underemphasized cause of failure in revision hip arthroplasty despite its higher dislocation rate than after primary THA. The effectiveness of posterior soft tissue repair in the posterior approach has been determined in primary THA. However, to the best of our knowledge, there are no reports dealing specifically with the effectiveness of posterior soft tissue repair in the posterior approach in revision hip arthroplasty. We investigated the influence of the posterior approach with soft tissue repair in revision hip arthroplasty by evaluating the rate of early posterior dislocation.

Material and Method: Ninety-one patients (96 hips) who had undergone revision hip arthroplasty through the posterior approach were observed for 1 year or until dislocation occurred. Fifty-six revision hip arthroplasties were performed using the posterior approach with soft tissue repair technique. The results of these procedures were compared with those of 40 revision hip arthroplasties that had been performed using the posterior approach without soft tissue repair.

Results: The dislocation rate of 10.0% in 40 hips using the posterior approach without soft tissue repair was reduced to 1.9% in 56 hips using the posterior approach with soft tissue repair.

Discussion: Considering the results, it is clear that the posterior soft tissue repair in revision hip arthroplasty is clinically important for achieving a lower dislocation rate after revision hip arthroplasty. We suggest that to prevent dislocation after revision hip arthroplasty when a posterior approach is used, the posterior soft tissue, including the capsule and short external rotators, should be preserved and repaired as much as possible.