Pulsed electrical stimulation in patients with osteoarthritis of the knee: follow up in 288 patients who had failed non-operative therapy.

BACKGROUND

Optimized pulsed electrical stimulation (PES) regulates chondrocyte genes, enhances production of cartilage matrix materials, and inhibits production of matrix catabolic factors.

METHODS

This prospective, cohort study examined the use of a PES device in treatment of knee osteoarthritis (OA) in patients who had failed non-operative therapy. Primary outcome measures were patient and physician global evaluation, and patient assessment of knee pain.

RESULTS

This study included 288 (95 men, 193 women) patients who used the device from 16 to more than 600 days (mean: 889 hours). Improvement in all efficacy variables (p < 0.001) occurred. A dose-response relationship between effect size and hours of usage was observed as cumulative time increased to more than 750 hours. Improvement in patient or physician global occurred in 59.0% of patients who used it less than 750 hours, and for 73.0% of those who used it more than 750 hours. An economic analysis of a sub-group of patients showed that 45.3% reduced nonsteroidal anti-inflammatory drug (NSAID) use by 50.0% or more.

CONCLUSIONS

A highly optimized PES device successfully attenuated knee OA symptoms in patients who had failed non-surgical therapy. Less than 250 hours of therapy provided relief, but improvement increased in a dose-response manner after 750 hours of cumulative use.