Analyzing glenohumeral torque–rotation response in vivo

Abstract

Background-Because the human shoulder has many degrees of freedom that allow redundant means of producing the same net humerothoracic motion, there are many impediments to objective, repeatable assessment of shoulder function in vivo. Devices designed to date have suffered from poor reliability. In this study we introduce a new device and methods to evaluate human shoulder kinematics and evaluate its reproducibility from subject to subject and from day to day.

The Relationship between Serum Relaxin Concentrations and Knee Valgus

“…The ankle and knee joints were defined as the midpoint between the digitized medial and lateral malleoli, and medial and lateral femoral condyles, respectively, whereas the spinal column was defined as the digitized space between C7-T1 and T12-L1 [19]. A rotation method, validated as capable of providing accurate positional data, was utilized to estimate the joint centers of the hips [20]. The hip joint centers were calculated from the rotation of the femur relative to the sacrum.…”

Pregnancy Results in Lasting Changes in Knee Joint Laxity

“…Compliance was measured as the slope (D) of the force (moment) by the translation (rotation) plot at the point (C) midway between the limits of the range of motion, A and B (Figure and formula below) . A larger absolute value of D indicates that more translation or rotation occurred with a given force or moment (ie, more compliant), whereas a smaller absolute value of D indicates that less translation or rotation occurred with a given force or moment (ie, less compliant).…”