Birmingham mid-head resection periprosthetic fractures: Case report.

Introduction: Total hip arthroplasty in young patients can cause problems when it comes to choosing a suitable implant. The Birmingham Mid-Head Resection prosthesis (BMHR) offers the option of preserving bone stock despite its poor quality in the femoral neck. Femoral neck fractures are a known complication of hip resurfacing prostheses and the main reason for revision surgery. Retaining the femoral implant may cause difficulties in osteosynthesis carried out with implants habitually used for intertrochanteric or femoral neck fractures (e.g., a screw-plate device or a cephalomedullary nail) [2].

Presentation Of Case: We present the case of an 81-year-old patient who underwent surgery for right hip osteoarthritis and received a Birmingham Mid-Head Resection prosthesis. She had no history of previous fractures due to frailty. While on holiday, she sustained a periprosthetic fracture as a result of a fall. While the most common fracture in resurfacing prosthesis is produced in the femoral neck, in this case the patient sustained a subtrochanteric fracture. This fracture was surgically treated by means of open reduction and internal fixation with trochanteric plate and three cerclages.

Discussion: Olsen et al. [8] described two fracture patterns: transcervical vertical shear type and subcapital type. In our patient's case, the fracture pattern was different to those described, as the fracture started in the cervical area and reached the subtrochanteric area. This change in the standard periprosthetic fracture pattern leads to a change in the therapeutic attitude that must be adopted.

Conclusion: BMHR prostheses are metal-on-metal implants that resulted from the development of the standard resurfacing prostheses used to treat hip osteoarthritis in young patients with the goal of preserving as much bone stock as possible. In this paper we will describe a rare complication in this type of prosthesis and how it was surgically treated after reviewing the available literature.