The contribution of the acetabular labrum to hip joint stability: a quantitative analysis using a dynamic three-dimensional robot model.

The acetabular labrum provides mechanical stability to the hip joint in extreme positions where the femoral head is disposed to subluxation. We aimed to quantify the isolated labrum's stabilizing value. Five human cadaveric hips were mounted to a robotic manipulator, and subluxation potential tests were run with and without labrum.

Locking and nonlocking plate fixation pubic symphysis diastasis management.

We evaluated the stability of locking and nonlocking plate fixation of the pubic symphysis in a cadaveric model of an unstable pelvic injury. Five fresh cadaver pelves--intact and with an unfixed simulated Tile B injury--were tested under compressive load simulating a 2-legged stance. On each pelvis, 3 pubic symphysis fixation constructs were tested: a 4-hole unicortical locking plate, a 4-hole bicortical locking plate, and a 4-hole bicortical compression plate.

Effect of pretension and suture needle type on mechanical properties of acellular human dermis patches for rotator cuff repair.

Background: Dermal grafts are used for rotator cuff repair and augmentation. Although the in vitro biomechanical properties of dermal grafts have been reported previously, clinical questions related to their biomechanical performance as a surgical construct and the effect of surgical variables that could potentially improve repair outcomes have not been studied.

Methods: This study evaluated the failure and fatigue biomechanics of acellular dermis constructs tested in a clinically relevant size (4 × 4 cm patches) and manner (loaded via sutures) for rotator cuff repair.