Effects of pericapsular soft tissue and realignment exercises for patients with osteoarthritis of the hip and Harris Hip Score below 60 points

Abstract

Objective

To investigate the effectiveness of pericapsular soft tissue and realignment (PSTR) exercises for patients with osteoarthritis (OA) of the hip and Harris Hip Score (HHS) below 60 points. Most previous studies of hip exercise have not been applied for patients with moderate to severe hip OA, especially those with an HHS below 60 points. Most studies of hip exercise in OA have involved muscle strength training, stretching, functional training and aerobic fitness programs, and have not included pelvic realignment exercise. We investigated the effect of pelvic realignment exercise for patients with hip OA and HHS below 60 points.

Methods

Design: multicenter, prospective, observational, single-arm study. Setting: clinical examination on an outpatient basis. Participants: 193 patients with hip OA and HHS below 60 points. Interventions: patient education and supervised PSTR exercises. Outcome measures: primary outcome: HHS; secondary outcomes: changes in numerical rating scale (NRS) scores, abduction of range of motion, Timed Up and Go (TUG) test within 30 min after PSTR exercises at baseline and other six items, full analysis set (FAS, all participants who performed PSTR exercises) and subgroup analysis (participants with minimal joint space (MJS) of 0 mm at baseline).

Results

FAS analysis (N = 193): significant differences in HHS were found between baseline and 3 month follow-up, and between baseline and 6 month follow-up in the Unilateral and Bilateral OA groups (p < .001). All mean differences were within the 95% confidence interval. Significant improvement in NRS scores, abduction of range of motion, and TUG test within 30 min after PSTR exercises were found at baseline (p < .001). Subgroup analysis (N = 130): the results revealed significant differences (p < .001) in HHS and NRS, abduction of range of motion and TUG test within 30 min after PSTR exercises at baseline, as in the FAS analysis.

Conclusion

Our findings suggested that PSTR exercises were effective for patients with HHS below 60 points, even those with MJS of 0 mm.

Clinical Trials Registry

20 July 2017 (UMIN000028277)

Keywords:

• Osteoarthritis
• hip
• home exercise
• pelvic realignment
• cartilage loss
• pain

Transparency

Declaration of funding

This study did not receive funding.

Declaration of financial/other relationships

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. CMRO peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Some of the results of this study were presented as an abstract and poster at the 2021 OARSI World Congress; 28 April–1 May 2021.

Author contributions

K.H. and T.T. contributed to study design, collection, analysis and interpretation of data, and drafting and revising of the manuscript. T.S. contributed to analysis and interpretation of data, use of statistics and critical revision of the manuscript. Y.T. and F.I. contributed to the explanations of PSTR exercises, writing the Discussion and analysis of patient characteristics at baseline (Table 1). All authors approved the final version of the manuscript.

Acknowledgements

K.H. and T.T. acknowledge the support of K. Toyota, S. Tokunaga, S. Soda, S. Aritake and S. Sakamoto (staff at the Clinical Research Support Center Kyushu). We wish to thank the staff at the Department of Rehabilitation of Fukuoka Wajiro Hospital and Asama General Hospital for their contributions to instruction for PSTR exercises. We are grateful for the support provided by the nurses and medical clerks of Fukuoka Wajiro Hospital and Asama General Hospital. The authors wish to thank all of the patients who participated in this study. We thank Benjamin Knight MSc from Edanz (https://jp.edanz.com/ac) for editing a draft of this manuscript.

Ethics statement

The study was carried out in accordance with the Declaration of Helsinki and was approved by the Fukuoka Wajiro Hospital and Asama General Hospital medical research ethics committees.