Are the yips a task-specific dystonia or "golfer's cramp"?

This study compared golfers with and without the yips using joint movement and surface electromyographic detectors. Fifty golfers (25 with and 25 without complaints of the yips) were studied while putting. All putts were videotaped. Surface electromyography assessed arm cocontraction. A CyberGlove II (Immersion Technologies, Palo Alto, CA) assessed right-arm angular movements. Primary analysis was done by subjective complaint of the yips, whereas secondary analysis was done by video evidence of an involuntary movement. When grouped by subjective complaints, there were no differences in any movement parameter. When grouped by video evidence of an involuntary movement, yips cases had more (P < 0.001) angular movement in wrist pronation/supination and a trend (P = 0.08) for wrist flexor/extensor cocontraction (yips: 7 of 17, 41.2%; no yips: 6 of 33, 18.2%). Golfers with video evidence of an involuntary movement while putting have excessive rotation of the right wrist in a pronation/supination motion and, as previously reported, a trend for wrist flexor/extensor cocontraction.