Relationships between Skeletal Muscle Characteristics of the Gluteus Medius and Gait Parameters in a Patient after Surgery for Osteoarthritis of Hip with Limp Remaining at 9 Months after Rotational Acetabular Osteotomy

Abstract

[Purpose] The purpose of this study was to investigate the effect of an intervention to improve electromechanical delay (EMD) of the gluteus medius (GM) for Duchenne gait. [Participant] A woman in her 40s participated in this study 9 months after rotational acetabular osteotomy. This patient exhibited Duchenne gait, despite a grade of more than 4 in manual muscle testing (MMT) of abduction of the affected hip, and EMD of the affected GM was prolonged compared with the unaffected side. [Intervention] The patient performed maximal isometric contractions many times a day for 5 days. [Results] The EMD, rate of force development, and median power frequency of the affected GM improved and with that, the patient showed improvement in pelvic and trunk tilt during gait. [Conclusion] These results suggest that the intervention to improve EMD of the affected GM was effective for this patient with Duchenne gait, despite a grade of more than 4 in MMT of the affected side after surgery for hip osteoarthritis.