A 5° medial wedge reduces frontal but not saggital plane motion during jump landing in highly trained women athletes

Michael F Joseph¹, Craig R Denegar¹, Elaine Horn¹, Bradley MacDougall¹, Michael Rahl¹, Jessica Sheehan¹, Thomas Trojian², Jeffery M Anderson¹, James E Clark¹, William J Kraemer¹

¹Department of Kinesiology, ²Department of Sports Medicine, University of Connecticut, Storrs, CT, USA

Abstract: Lower extremity mechanics during landing have been linked to traumatic and nontraumatic knee injuries, particularly in women’s athletics. The effects of efforts to mitigate these risks have not been fully elucidated. We previously reported that a 5° medial wedge reduced ankle eversion and knee valgus. In the present report we further investigated the effect of a 5° medial wedge inserted in the shoes of female athletes on frontal plane hip motion, as well as ankle, knee, hip, and trunk saggital plane motion during a jump landing task. Kinematic data were obtained from 10 intercollegiate female athletes during jump landings from a 31 cm platform with and without a 5° medial wedge. Hip adduction was reduced 1.98° (95% CI 0.97–2.99°) by the medial wedge but saggital plane motions were unaffected. A 5° medial wedge reduces frontal plane motion and takes the knee away from a position associated with anterior cruciate ligament injury and patellofemoral pain syndrome. Although frontal plane motion was not captured it is unlikely to have increased in a bilateral landing task. Thus, it is likely that greater muscle forces were generated in these highly trained athletes to dissipate ground reaction forces when a medial wedge was in place. Additional investigation in younger and lesser trained athletes is warranted to assess the impact of orthotic devices on knee joint mechanics.

Keywords: jump landing, foot orthotic, lower extremity kinematics, knee biomechanics, knee injury