Electromyographic and Joint Kinematic Patterns in Runner’s Dystonia

Abstract

Runner’s dystonia (RD) is a task-specific focal dystonia of the lower limbs that occurs when running. In this retrospective case series, we present surface electromyography (EMG) and joint kinematic data from thirteen patients with RD who underwent instrumented gait analysis (IGA) at the Functional and Biomechanics Laboratory at the National Institutes of Health. Four cases of RD are described in greater detail to demonstrate the potential utility of EMG with kinematic studies to identify dystonic muscle groups in RD. In these cases, the methodology for muscle selection for botulinum toxin therapy and the therapeutic response is discussed. Lateral heel whip, a proposed novel presentation of lower-limb dystonia, is also described.

Keywords

• runner’s dystonia
• task specific dystonia
• lower extremity dystonia
• kinematics
• electromyography
• gait analysis
• coactivation
• compensatory activity
• lateral heel whip
• botulinum toxin