3-DIMENSIONAL KINEMATICS AND TRUNK MUSCLE MYOELECTRIC ACTIVITY IN THEYOUNG LUMBAR SPINE - A DATABASE

Objective: To document the three-dimensional (3D) kinematics of the lu mbar spine and the myoelectric activity of trunk muscles throughout th e range of motion in selected tasks performed by healthy subjects. Des ign: A survey of a single population. Setting: A research laboratory i n a university setting. Participants: Twenty-four men and women, unive rsity-age, with no history of chronic lower back pain volunteered for this study. Interventions: The selected tasks consisted of lateral ben d and axial twists to the right and left plus four different flexion-e xtension tasks that varied a hand-held weight (10kg and 0kg), and flex ion-extension velocity (free-paced and 20 degrees/sec). Main Outcome M easure: 3D lumbar spine kinematics and normalized, linear enveloped el ectromyogram (EMG) of trunk muscles. Results: The motion time historie s were illustrated graphically. Consistent spinal kinematics and EMG a ctivation patterns during each task across subjects were seen. Peak di splacement values between tasks, using one-way analysis of variance, s howed no significant difference. Conclusion: A database of healthy spi ne kinematics and normalized linear enveloped trunk muscle activation patterns were developed for future comparison of elderly and pathologi cal subjects. (C) 1998 by the American Congress of Rehabilitation Medi cine and the American Academy of Physical Medicine and Rehabilitation.