Introduction: It was hypothesized that ipsilateral upper extremity loading will decrease hip abductor activity by decreasing the adductor moment and thus relieving the symptoms of patients with gluteus medius tendinitis. The aim of the study was to test the hypothesis with a electrophysiological and clinical study.

Materials and Methods: Seven voluntary men with no hip complaint were included in the electrophysiological phase of the study. The motor unit activities of the gluteus medius were measured for each subject during the consecutive loading of the ipsilateral, contralateral and both upper extremities, with 2, 3, 5 and 7 kilograms.

Seventeen patients (age range 34–67) with acute symptoms of gluteus medius tendinitis were included in the clinical phase of the study. Dynamic VAS scores were recorded for each patient during gait with consecutive loading of the ipsilateral, contralateral and both upper extremities, for each 2, 3, 5 and 7 kilograms. Wilcoxon and Mann-Whitney U tests were used in statistical analysis. The p values below 0.05 were considered significant.

Results: In the electrophysiologic study the ipsilateral upper extremity loading with 7 kg in 4 patients, and with 5 and 7 kilograms in 2 patients resulted in a motor unit activities with moderate interference, while motor unit activities with full interference were recorded during all other loadings. The motor unit activity interference scores recorded during the ipsilateral upper extremity loading with 5 kilograms of above, were significantly less then all other loading combinations (p < 0.05).

In the clinical study, the ipsilateral upper extremity loading with 3 kilograms and above resulted in significantly less VAS scores then the other loading combinations (p< 0.05).

Conclusion: Ipsilateral upper extremity loading decrease the motor unit activity of the ipsilateral gluteus medius muscle and relieves the symptoms of the patients with gluteus medius tendinitis. Ipsilateral upper extremity loading can lead up to new strategies in the rehabilitation of gluteus medius tendinitis.