The use of patterned neuromuscular stimulation to improve hand function following surgery for ulnar neuropathy.

A 60-year-old man with wasting and weakness of the right hand following ulnar nerve entrapment at the elbow was referred for electrotherapy. An ulnar nerve transposition had been performed 2 years previously. This had produced some improvement in nerve conduction without significantly improving hand muscle function. The right first dorsal interosseous muscle (FDI) was stimulated for 4 hours per day over a 6-week period with a stimulus pattern replicating the discharge of a single motor unit from a healthy, fatigued FDI (patterned neuromuscular stimulation or PNMS). The response was assessed using a single case design. Significant improvements in the strength and fatigue resistance of the FDI were observed, associated with improvements in general hand function. PNMS may be useful in restoring hand function in patients with muscle atrophy following entrapment neuropathy.