Affiliations: [a] Department of Orthopaedic Surgery, Fukuoka University,
Fukuoka, Japan | [b] Department of Mechanical Engineering, Faculty of
Engineering, Fukuoka University, Fukuoka, Japan
Note: [] Corresponding author: Akira Maeyama, M.D., Department of
Orthopaedic Surgery, School of Medicine, Fukuoka University, 7-45-1 Nanakuma,
Jonan-ku, Fukuoka 814-0180, Japan. Tel.: +81 92 801 1011; Fax: +81 92 864 9055;
E-mail: akira.maeyama0713@joy.ocn.ne.jp
Abstract: PURPOSE: We compared the dynamic instability of dysplastic hips
using a triaxial accelerometer before and after abductor muscle strengthening
exercises to determine if such exercises could achieve improvements in hip pain
and associated symptoms. METHODS: We evaluated 17 hips in 17 female patients with a mean age
of 37 years who presented with hip joint symptoms and acetabular dysplasia. At
the initial diagnosis, we used a triaxial accelerometer to measure dynamic
instability of the hip during walking. Patients were taught how and instructed
to perform abductor muscle strengthening exercises for 3 months. After this
time, we re-measured. we compared these values before and after exercise. RESULTS: The average abductor muscle strength improved from 104.4
± 35.4 N to 124.3 ± 35.9 N after exercise, an improvement of
approximately 16%. The overall magnitude of acceleration significantly
decreased from 2.40 ± 0.34 m/s^{2} at pre-exercise to
1.82 ± 0.28 m/s^{2} at post-exercise (p < 0.0001).
The VAS also significantly improved (p=0.0005). In all cases, hip joint
symptoms were significantly improved by the performance of the studied abductor
muscle strengthening exercises. CONCLUSIONS: Using a triaxial accelerometer, we have shown that
instability of the hip during walking can be improved by abductor muscle
strengthening exercises.
