Failure of larger-diameter metal-on-metal total hip arthroplasty resulting from anterior iliopsoas impingement.

Anterior iliopsoas impingement is a recognized cause of persistent groin pain after total hip arthroplasty. We report 3 patients with failed total hip arthroplasties resulting from anterior iliopsoas and capsular impingement secondary to a metal femoral ball with a diameter larger than the native femoral head. All patients had the same implant design.

Case report: the nest technique for management of a periprosthetic patellar fracture with severe bone loss.

Periprosthetic patellar fracture with marked loss of bone stock presents a significant problem in total knee arthroplasty. Treatment outcomes are often unsatisfying and may lead to disruption of the extensor mechanism of the knee. We present a patient with a Type IIIb periprosthetic patellar fracture treated by a novel approach.

In vitro analysis of anterior and posterior fixation in an experimental unstable burst fracture model.

Study Design: A biomechanical comparison of fixation constructs in an experimental fracture model.

Objective: To determine the relative postoperative stability of anterior graft and plating with that of posterior or combined fixation constructs in an unstable thoracolumbar burst fracture model.

Summary Of Background Data: Several treatment modalities have been proposed for unstable thoracolumbar burst fractures, but the optimal technique is unclear.

Validation, reliability, and complications of a tethering scoliosis model in the rabbit.

This study was conducted to refine a small animal model of scoliosis, and to quantify the deformities throughout its growth period. Subcutaneous scapula-to-contralateral pelvis tethering surgery was selected due to its minimally invasive nature and potential applicability for a large animal model. The procedure was performed in 7-week-old New Zealand white rabbits.

Measurement of in vivo intradiscal pressure in healthy thoracic intervertebral discs.

Study Design: In vivo pressures were measured in radiologically healthy middle and lower thoracic discs in 6 adult volunteers.

Objectives: To quantify and compare intradiscal pressures from the middle and lower thoracic spine during various body positions and maneuvers, and to investigate the potential variation of these pressures with orientation of the measurement transducer.

Summary Of Background Data: In vivo intradiscal pressures have been reported for the lumbar spine; however, the authors are unaware of any studies presenting intradiscal pressures in the thoracic spine.