RESUMEN
The purpose of this study was to test whether the menisci displace under joint compression combined with internal-external torques and anterior-posterior forces at fixed flexion angles. We further determined differences in displacements between the medial and lateral menisci. Loads were applied to the joint, and joint load and displacements were measured. Meniscal displacements were measured radiographically. With a joint compressive load of 1 kN, internal and external joint rotations caused the lateral meniscus to displace, on average, 0.37 mm deg-1 in the anterior-posterior direction, while the medial meniscus displaced 0.19 mm deg-1. Anterior and posterior joint translation, performed under 1 kN joint compression, caused the lateral meniscus to displace, on average, 0.66 mm mm-1 in the anterior-posterior direction, while the medial meniscus displaced 0.43 mm mm-1. Greater meniscal displacements were found at 15 and 30 degrees flexion than at 0 degrees for the lateral meniscus in internal rotation. Lateral meniscal displacements were larger than those of the medial with posterior tibial translation at full extension and with internal rotation.
Asunto(s)
Articulación de la Rodilla/fisiología , Meniscos Tibiales/fisiología , Tibia/fisiología , Fémur/fisiología , Humanos , Modelos Lineales , Meniscos Tibiales/anatomía & histología , Rotación , Estrés MecánicoRESUMEN
A load cell was developed that can reliably monitor longitudinal traction forces applied to limbs during several different orthopaedic procedures. This permitted determination of tensile loads and the effects of patient limb positions on tension magnitudes. The relationships between the magnitude and duration of applied tension to functional nerve changes were also studied. This preliminary report reviews traction force data on seven patients for eight operations. Mean peak loads for femoral, tibial, and hip procedures were 686, 356, and 306 N, respectively. Adduction of the limb around a fixed peroneal post caused great increases in traction forces.