A novel method of inducing muscle cramps using repetitive magnetic stimulation.
The lack of a practical model has hampered attempts to study the pathophysiology of muscle cramps. We investigated the feasibility, efficacy, and reproducibility of repetitive magnetic stimulation in producing experimental cramps. In 14 healthy subjects, the tibial nerve at the ankle was stimulated with a magnetic stimulator at rates beginning at 4 Hz to a maximum of 20 Hz. The frequency was gradually increased until a cramp was produced. Ten of 14 subjects demonstrated a muscle cramp. All subjects rated the discomfort of the procedure to be mild or moderate. Repeat testing yielded values that were highly reproducible. This technique holds promise for clinical studies and therapeutic trials.
Caress
J B
JB
Department of Neurology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, North Carolina 27157-1078, USA. jcaress@wfubmc.edu
Bastings
E P
EP
Hammond
G L
GL
Walker
F O
FO
D000328:Adult; D000842:Ankle / Q000502:physiology; D004574:Electromagnetic Fields; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D009120:Muscle Cramp / Q000503:physiopathology*; D010812:Physical Stimulation; D015203:Reproducibility of Results; D013979:Tibial Nerve / Q000502:physiology; D014034:Toes / Q000294:innervation / Q000502:physiology