The Effects of Knee Joint Effusion on Quadriceps Electromyography During Jogging
Michael R. Torry1,, Michael J. Decker1, Peter J. Millett3, J. Richard Steadman2, William I. Sterett2
1Biomechanics Research Lab., Steadman"Hawkins Research Foundation Vail, Colorado, USA 2Steadman Hawkins Sports Medicine Clinic, Vail, Colorado USA 3Department of Orthopedics, Brigham and Women’s Hospital, Harvard University, Boston, MA, USA
Michael R. Torry ✉ Director, Biomechanics Research Laboratory, Steadman Hawkins Sports Medicine Foundation, 181 West Meadow Drive, Ste 1000, Vail, Colorado 81657, USA Email: mike.torry@shsmf.org
Received: 26-10-2004 -- Accepted: 30-11-2004 Published (online): 01-03-2005
ABSTRACT
To investigate and describe the influence of intra-articular effusion on knee joint kinematics and electromyographic (EMG) profiles during jogging. Thirteen individuals underwent a 20 cc 0.9% saline insufflation of the knee joint capsule and completed 8 jogging trials. Stance phase, sagittal plane knee joint kinematics and thigh muscular EMG profiles were compared pre- and post-insufflation utilizing a paired t-test ( = 0.05). Mild knee effusion caused a reduction in vastus medialis (p = 0.005) and lateralis (p = 0.006) EMG activity. The rectus femoris, biceps femoris and medial hamstring muscles did not exhibit changes due to this protocol. There were no changes in the sagittal plane knee joint kinematic pattern. Twenty cc effusion can cause quadriceps inhibition in the vastus medialis and the vastus lateralis in otherwise healthy individuals during jogging. This study provides baseline data for the effects of mild knee joint effusion on thigh musculature during jogging.