Efficiency of Neuromuscular Electrical Stimulation and Transcutaneous Nerve Stimulation on Hemiplegic Shoulder Pain: A Randomized Controlled Trial

Objective: To compare the efficacy of neuromuscular electrical stimulation (NMES) and transcutaneous nerve stimulation (TENS) on hemiplegic shoulder pain (HSP).

Design: This is a prospective randomized controlled trial.

Setting: A rehabilitation hospital.

Participants: Participants (N=90) were randomized into NMES (n=36), TENS (n=36), or control groups (n=18).

Interventions: NMES (15Hz, pulse width 200μs) was applied to supraspinatus and deltoids (medial and posterior parts), whereas TENS (100Hz, pulse width 100μs) was used on the same areas. The surface electrodes were placed near the motor points of the supraspinatus and medial or posterior bundle of deltoids. The 4-week treatment consisted of 20 sessions, each session composed of 1 hour of stimulation per day. Routine rehabilitation program without any stimulation was administered to the control and the NMES/TENS groups. Numerical rating scale (NRS), active/passive range of motion (AROM/PROM) of shoulder, upper extremity Fugl-Meyer Assessment (FMA), modified Ashworth scale (MAS), Barthel Index (BI), and stroke-specific quality of life scale (SSQOLS) were assessed in a blinded manner at baseline, 2, 4, and 8 weeks after treatment, respectively.

Main outcome measures: The primary endpoint was the improvement from baseline in NRS for HSP at 4 weeks.

Results: NRS scores in NMES, TENS, and control groups had decreased by 2.03, 1.44, and 0.61 points, respectively after 4 weeks of treatment, with statistically significant differences among the 3 groups (P<.001). The efficacy of the NMES group was significantly better than that of the TENS group (P=.043). Moreover, the efficacy of NMES and TENS groups was superior to that of the control group (P<.001, P=.044, respectively). The differences in the therapeutic efficacy on shoulder AROM/PROM, FMA, MAS, BI, and SSQOLS scores were not significant among the 3 groups.

Conclusions: TENS and NMES can effectively improve HSP, the efficacy of NMES being distinctly superior to that of TENS in maintaining long-term analgesia. However, NMES was not more efficacious than the TENS or control group in improving the shoulder joint mobility, upper limb function, spasticity, the ability of daily life activity, and stroke-specific quality of life in HSP patients.