Effects of hip joint transverse plane range of motion with a modeled effusion and capsular tear: A cadaveric study.

BACKGROUND: Multiple factors contribute to range of motion of the hip joint in the transverse plane: bony anatomy, hip capsule, corresponding ligaments, articular labrum, ligamentum teres, and negative intra-articular pressure. We hypothesized that violation of the negative pressure of the hip and simulation of an effusion would increase range of motion in the transverse plane in a cadaver model. METHODS: Ten hip specimens were obtained and dissected with the femur and iliac wing mounted in a custom joint-testing rig in neutral position. Specimens were tested at 0 and at 90° of flexion with 1.5Nm internal and external rotational torque. Three conditions were assessed: (1) intact specimen, (2) an effusion modeled by a 10ml saline infusion, and (3) a capsular tear. FINDINGS: The modeled effusion decreased rotational range of motion limits in both 0 and 90° of flexion, with a greater effect on the specimens at 0° flexion in external rotation with 4.1° less external rotation (p=0.009). A modeled capsular tear increased rotational motion limits in 0° of flexion in both internal and external rotation and in 90° flexion in internal rotation only (p<0.025). INTERPRETATION: An effusion may decrease the rotation of the hip, and a capsular tear may increase its rotation. This should be considered in hips with traumatic capsular tears or arthroscopic portals.

"Double-Row Rip-Stop" Technique for Arthroscopic Rotator Cuff Repair.

Rotator cuff repair depends on both the fixation strength of the chosen repair construct and the local healing response of the repaired tissue. Among a growing discussion surrounding the superiority of one surgical technique over another, the surgeon's ability to complete a rotator cuff repair with technical acuity in a timely manner remains paramount. Double-row repairs as well as rip-stop configurations have been proposed to limit failures found after arthroscopic rotator cuff repairs. Implementation of both techniques during arthroscopic shoulder surgery may represent a technical challenge for the average orthopaedist. The purpose of this article is to give simple instructions for reproduction of an arthroscopic double-row rip-stop repair for rotator cuff fixation.