Knee stability after articulated external fixation.

Background: Articulated external fixation has been proposed as a method to protect ligament reconstructions while allowing aggressive and early postoperative rehabilitation after knee dislocation. However, the ability of these fixators to protect and stabilize the knee joint has not been clearly determined.

Hypothesis: Articulated external fixation can reduce anteroposterior translation in the cruciate-deficient knee and reduce cruciate ligament strain in cases of intact or reconstructed ligaments.

A laboratory model to evaluate cutout resistance of implants for pertrochanteric fracture fixation.

Objectives: To establish a laboratory model of implant cutout, which can evaluate the effect of implant design on cutout resistance in a clinically realistic "worst case" scenario.

Setting: Orthopaedic biomechanics laboratory.

Design: Implant cutout was simulated in an unstable pertrochanteric fracture model, which accounted for dynamic loading, osteoporotic bone, and a defined implant offset.