Attempts to eliminate STA using percutaneous bone fixtures have been successful however, these methods are highly invasive and likely alter joint motion, especially during jumping and cutting maneuvers ( Lafortune et al., 1992 Cappozzo et al., 1996 Holden et al., 1997). While these techniques improve segment tracking they do not eliminate STA. Cluster based motion capture techniques have been developed to mitigate the effect of STA ( Andriacchi et al., 1998). STA limits the accuracy of joint metrics at the level of the ligaments and articulating surfaces.
#JUMPCUT CAREERS SKIN#
However, OMC is sensitive to soft tissue artifact (STA), where motion of skin mounted markers move relative to the underlying bones, particularly during the landing and support phases of a movement ( Cappozzo et al., 1996 Reinschmidt, van den Bogert, et al., 1997). When combined with ground reaction forces and a biomechanical model, OMC is a powerful tool for providing insight into the biomechanics of the knee during these high speed maneuvers. The field-of-view (FOV) of OMC systems is large enough to capture the motion of multiple joints over an entire jumping and cutting movement. Optical motion capture (OMC) technologies have been used to non-invasively quantify 3-D joint kinematics, including jumping and cutting ( Ford et al., 2005). Understanding the biomechanics of activities associated with non-contact ACL injury would provide insight into injury mechanisms and may provide evidence in support of specialized training and rehabilitation techniques to minimize injury and optimize treatment ( McNair et al., 1990 Boden et al., 2000). The mechanisms associated with non-contact ACL injury are not well understood and most likely occur from a combination of risk factors including environmental, anatomical, hormonal, and biomechanical ( Griffin et al., 2006). They account for ~70% of the estimated 400,000 ACL injuries sustained in the United States each year ( McNair et al., 1990 Junkin et al., 2009). Non-contact ACL injuries are those sustained without contact with another athlete. This study provides information on the kinematic discrepancies between OMC and biplanar videoradiography that can be used to optimize methods employing both technologies for studying dynamic in vivo knee kinematics and kinetics during a jump-cut maneuver.Īctivities involving jumping, landing, and cutting are commonly associated with non-contact anterior cruciate ligament (ACL) injuries ( Griffin et al., 2006 Gianotti et al., 2009). Kinematic deviations between the two techniques increased significantly after contact. The OMC and biplanar videoradiography knee joint kinematics were in best agreement before landing. Over the entire activity, the within-bone motion differences between the two motion capture techniques were significantly lower for the tibia than the femur for two of the rotational axes (flexion/extension, internal/external) and the origin. The knee joint kinematic measurements were compared during two periods: before and after ground contact. The within-bone motion differences were compared using anatomical coordinate systems for the femur and tibia, respectively. Ten volunteers performed a jump-cut maneuver while their landing leg was imaged using optical motion capture (OMC) and biplanar videoradiography. The goal of this study was to compare how STA affects the six-degree-of-freedom motion of the femur and tibia during a jump-cut maneuver associated with non-contact ACL injury. Biplanar videoradiography offers a unique approach to collecting skeletal motion without STA. Optical motion capture is widely used however, it is subject to soft tissue artifact (STA).
Jumping and cutting activities are investigated in many laboratories attempting to better understand the biomechanics associated with non-contact ACL injury.
0 kommentar(er)
