We report a case of a 51-year-old lady, who underwent a femoral shortening using a fixator assisted blade plate after total hip replacement. The patient had a total hip replacement on the other side with previous revisions, which resulted in a leg length discrepancy. We used the above technique to control the shortening and preserve the mechanical and anatomical axis of the femur.Keywords External fixator Á Femoral shortening Á Total hip replacement
Case reportA 35-year-old lady with a history of neglected developmental dysplasia (DDH) of the right hip presented with increasing hip pain, back pain and progressive knee deformity. She subsequently underwent conversion of the pseudoarthrosis to a total hip replacement. At the time of surgery, despite adductor tenotomy, it was difficult to relocate the trial prosthesis and a resection of the proximal femur was necessary. A straight stem prosthesis was cemented in the femur (Fig. 1).Ten years later the patient required a revision of the acetabular component as a consequence of aseptic loosening. The acetabular reconstruction was undertaken using a cemented socket and with impacted bone graft. The reconstruction lasted for 9 more years before a further revision was required. There was extensive bone loss in the acetabulum and the reconstruction was performed using a Burch Schneider support ring, mesh and again with impaction bone graft. The bone stock in the proximal femur was so poor that a proximal femoral allograft with an uncemented stem was used to reconstruct the proximal femur. A leg length discrepancy of 5 cm remained.Increasingly symptomatic osteoarthritis in the left hip necessitated a left primary arthroplasty to be performed 3 years later. Six months after the left THR (age 51), she presented with increasing back pain attributed to a 5-cm discrepancy in leg length (Fig. 2). Shortening of the left femur was done by performing an external fixator-assisted shortening through a supracondylar resection and internal stabilisation with a blade plate.
Operative techniqueA limb reconstruction system (LRS) external fixator (Orthofix SRL, Italy) with four screws (150/50) was inserted in the sagittal plane under X-ray control perpendicular to the anatomical axis of the femur. Two screws were inserted above and two below the proposed level of femoral resection (Fig. 3). Through a lateral incision and subperiosteal approach a 4-cm segment of the distal femur was removed. The femur was then gradually shortened using the compression-distraction device on the fixator until bone contact at the edges of the osteotomy was achieved. With the fixator still in place, the newly shortened femur