Percutaneous Intramuscular Neuromuscular Electric Stimulation for the Treatment of Shoulder Subluxation and Pain in Patients With Chronic Hemiplegia: A Pilot Study.

Percutaneous Intramuscular Neuromuscular Electric Stimulation for the Treatment of Shoulder Subluxation and Pain in Patients With Chronic Hemiplegia: A Pilot Study Yu DT, Chae J, Walker ME, Fang ZP (Department of Physical Medicine and Rehabilitation and Department of Orthopedics, MetroHealth Medical Center; Center for Physical Medicine and Rehabilitation, Department of Biomedical Engineering, Case Western Reserve University; NeuroControl Corp, Cleveland, Ohio), Arch Phys Med Rehabil. 2001;82:20-25.

The purpose of this pilot study was to examine the feasibility of using percutaneous neuromuscular electrical stimulation (NMES), rather than transcutaneous NMES, to treat shoulder subluxation, a common cause of shoulder pain in people with hemiplegia. The authors also gathered preliminary data on efficacy and made suggestions for continued research to further refine this technique.

Eight patients (6 men, 2 women; median age=60 years, range=39-75 years) with chronic hemiplegia (median duration=11 months, range=6-31 months) and shoulder subluxation who were medically and neurologically stable were treated with percutaneous electrodes implanted into the posterior deltoid and supraspinatus muscles. Stimulation with a balanced biphasic current at 12 Hz and a duty cycle of 10 seconds on/10 seconds off was delivered for 6 hours each day for 6 weeks (total of 252 hours). Measurements of glenohumeral subluxation by radiograph, shoulder external rotation range of motion (ROM), motor function, and disability were done pretreatment (TI), 24 hours after the completion of 6 weeks of treatment (T2), and 3 months after treatment (T3).

At TI, the mean vertical subluxation was 10.3 [+ or -] 8.4 mm, the median rating for intensity of shoulder pain (as measured on the Brief Pain Inventory [BPI]) was 5, the mean range of pain-free shoulder external rotation was 18.5 [degrees] [+ or -] 14.9 [degrees], the median rating of motor function (as measured on the Fugl-Meyer Motor Test [FMT]) was 5, and the median score on the Functional Independence Measure (FIM) was 25.5. At T2 and T3, the researchers reported statistically significant decreases in shoulder subluxation (mean=5.0 [+ or -] 7.4 mm and 3.3 [+ or -] 6.1 mm, respectively) and pain intensity (median BPI scores=0 and 0.5, respectively) and increases in pain-free shoulder external rotation (mean=36.9 [degrees] [+ or -] 8.2 [degrees] and 29.4 [degrees] [+ or -] 10.5 [degrees], respectively) and FIM scores (median score=30 and 33, respectively). Motor function improved somewhat at T2, but was significantly improved at T3 (median FMT scores=6 and 15.5, respectively).

Although they acknowledged that the small sample size and short length of follow-up limited the predictive value of their data, the authors concluded that percutaneous NMES is feasible for treatment of the painful shoulder in people with hemiplegia. They cited a need to better understand the natural history of shoulder pathology in hemiplegia in order to guide further research on the optimal number and combination of muscles to be stimulated, the position of the patient for measurements, stimulus parameters, and dose-response relationships.

Marilyn Mieras, PT University of the Pacific Stockton, Calif