Periprosthetic tissue metal content but not serum metal content predicts the type of tissue response in failed small-diameter metal-on-metal total hip arthroplasties.

Background: Tissue responses to periprosthetic metal wear debris are complex and poorly understood. There are two predominant tissue responses: a nonspecific macrophage-mediated granulomatous response and lymphocyte-dominated response, which has immunological memory and is mediated by T cells. Delayed hypersensitivity-type responses may accelerate aseptic loosening of arthroplasty implants.

Does ligament balancing technique affect kinematics in rotating platform, PCL retaining knee arthroplasties? A prospective randomized study.

The goal of this prospective, randomized, blinded trial was to determine if ligament balancing techniques for rotating platform TKA affect postoperative knee kinematics. Sixteen patients with unilateral rotating platform TKA consented to participate in this institutional review board approved study. Eight patients were randomly selected to receive ligament balancing with an instrumented joint spreader device and eight patients received ligament balancing using fixed thickness spacer blocks.

[Importance of blade geometry for stability of fixation with short intramedullary nailing systems for the proximal end of the femur (gliding nail)].

Three biomechanical examinations of the double-T blade of the gliding nail were performed. Under alternating load, also after 100,000 cycles and 2000 N load, no instability occurred after gliding nail osteosynthesis. The best relationship between the introduction forces of the blade (1.

Isometry of the posterior cruciate ligament. Effects of functional load and muscle force application.

The effects of functional load and muscle force application on isometry of the posterior cruciate ligament were determined. Eight fresh-frozen cadaver knees were mounted in a custom-designed rig. A full range of motion and muscle forces were applied through the quadriceps, hamstring, and gastrocnemius tendons during a simulated static squat maneuver.

Collagen shortening. An experimental approach with heat.

Decreasing joint laxity is a clinical goal of ligament reconstructions. This in vitro study examined the structural and histologic effects of heat shrinkage of human collagen. Two preliminary studies were performed to assess the effect of heat on fresh frozen human tendons obtained from a local tissue bank.