The effectiveness of superimposed neuromuscular electrical stimulation combined with strengthening exercises on patellofemoral pain: A randomized controlled pilot trial

Abstract

BACKGROUND:

Patellofemoral pain (PFP) is one of the most common disorders of the knee. Neuromuscular electrical stimulation (NMES) is often assumed by clinicians to be an effective adjunctive therapy to quadriceps strengthening.

OBJECTIVE:

The aim of this study was to assess the efficacy of superimposed NMES combined with strengthening exercises to improve the recovery of quadriceps strength and function in patients with PFP.

METHODS:

This study was planned as a single blind randomized controlled pilot study. A total of twenty-seven patients diagnosed with PFP were randomly assigned into 2 groups. Patients received superimposed NMES in addition to the standardized program (Group I) or only the standardized program (Group II). The patients in both groups were treated 3 times a week for 6 weeks and followed at 12 weeks. Primary outcome measure was quadriceps isokinetic muscle strength. The changes in dependent variables before treatment, 6 ${}^{\text{th}}$ , and 12 ${}^{\text{th}}$ weeks were analyzed using a 2 $\times$ 3 mixed-model analysis of variance.

RESULTS:

There were significant improvements in the within groups statistics of all parameters for both groups ( $p<$ 0.05). No differences in quadriceps strength, Kujala and Lysholm scores between groups were found at the different time points [F (2, 21) $=$ 0.86; $p=$ 0.12, F (2, 21) $=$ 0.001; $p=$ 0.97, F (2, 21) $=$ 0.12; $p=$ 0.73, respectively].

CONCLUSIONS:

The results indicate that superimposed NMES combined with the standardized rehabilitation program has no clinically significant superiority to standardized rehabilitation program alone.