Relationship of core stability on pain and functional levels in patients diagnosed with hip osteoarthritis

Abstract

Introduction Osteoarthritis (OA) is a disease commonly encountered in the medical field, one that is caused by not only by ‘wear and tear’ of the joint but also because of more complex action characterised by molecular, anatomical and physiological changes. OA is a chronic joint disorder in which there is progressive softening and disintegration of articular cartilage accompanied by a new growth of cartilage and bone at the joint margins (osteophytes) and capsular fibrosis. The aetiology is genetic, metabolic, hormonal, mechanical and ageing. The hip is the second most frequently affected joint following the knee joint. Muscle strength is greatly affected by OA with the hamstrings, quadriceps and other mucles around the hip joint being significantly impaired. Pain, stiffness and dysfunction especially during activities of daily living can be a direct consequence of OA. As a result of all these factors, health-related quality of life is negatively affected, which results in the patient being referred for a total hip arthroplasty. Programmes aimed at the management of knee OA, ones which focus on quadriceps strengthening exercises, are now evidence-based. Importance is also being given to optimal core stability. However, research investigating the management of hip osteoarthritis is lacking, with available guidelines for therapeutic exercise prescription being expert based. The only research available focuses on patients with knee OA and lacks adequate methodological frameworks. Therefore, this study aimed to explore this research gap and investigate the effect of a 12-week core exercise programme on pain levels and functionality in patients with hip OA. Methodology A multi-arm parallel-group randomised controlled trial was carried out. Random allocation of 60 participants into 3 groups was carried out: the control group, the hip exercise group and the hip and core exercise group. Data was recorded at week 0 (baseline) and the week 12 following completion of the programme. All participants were at baseline asked about their general demographic data, following which these outcome measures were carried out: Numerical Pain Rating Scale (NPRS), Western Ontario and McMaster Universities (WOMAC) Scale, 6 MWT, peak isometric lower limb muscle testing, core stability and the 4-stage balance test. The control group received no intervention; the hip exercise group were subject to a set of hip exercises and the hip and core exercise group performed hip exercises and core muscle exercises. Results Statistically significant improvements resulted in all outcome measures following a 12-week exercise programme in all outcome measures for participants in the hip and core exercise group, followed by statistically significant gains for participants in the hip exercise group but to a lesser degree than the former group. The control group registered no change. Data for the three groups is as follows: 6MWD p=0.001, p<0.001, p=0.928; NPRS p=0.009, p=0.035, p=0.325; WOMAC p=0.005, p<0.001, p=0.032; Core stability p<0.001; balance: Stage 3 p=0.720; Stage 4 p=0.098. Conclusion Both clinical and statistically significant improvements in pain levels, functionality, lower limb strength, core muscle strength and balance resulted following a 12 week exercise programme. These were highly pronounced in participants enrolled in the hip and core exercise group.