Sagittal alignment and mobility of the thoracolumbar spine are associated with radiographic progression of secondary hip osteoarthritis.

OBJECTIVE: To identify predictors of radiographic progression of hip osteoarthritis (OA) over 12 months among functional hip impairments and spinal alignment and mobility. DESIGN: Fifty female patients with secondary hip OA, excluding those with end-stage hip OA, participated in this prospective cohort study. Joint space width (JSW) of the hip was measured at baseline and 12 months later. With radiographic progression of hip OA over 12 months (>0.5 mm in JSW) as dependent variable, logistic regression analyses were performed to identify predictors for hip OA progression among functional impairments of the hip and spine with and without adjustment for age, body mass index (BMI), and minimum JSW at baseline. The independent variables were hip pain, Harris hip score (HHS), hip morphological parameters, hip passive range of motion (ROM) and muscle strength, and alignment and mobility of the thoracolumbar spine at baseline. RESULTS: Twenty-one (42.0%) patients demonstrated radiographic progression of hip OA. Multivariable logistic regression analysis showed that larger anterior inclination of the spine in standing position (adjusted OR [95% CI], 1.37 [1.04-1.80]; P = 0.028) and less thoracolumbar spine mobility (adjusted OR [95% CI], 0.96 [0.92-0.99]; P = 0.037) at baseline were statistically significantly associated with radiographic progression of hip OA, even after adjustment for age, BMI, and minimum JSW. CONCLUSIONS: The findings suggest that spinal alignment and mobility should be considered when assessing risk and designing preventive intervention for radiographic progression of secondary hip OA.

Daily cumulative hip moment is associated with radiographic progression of secondary hip osteoarthritis.

OBJECTIVE: To investigate whether higher daily cumulative hip moment at baseline is associated with subsequent radiographic progression of hip osteoarthritis (OA) over 12 months. DESIGN: Fifty patients with secondary hip OA, excluding patients with end-stage hip OA, participated in this prospective cohort study. Joint space width (JSW) of the hip was measured at baseline and 12 months later. With radiographic progression of hip OA (>0.5 mm/year in JSW) as dependent variable (yes/no), univariable and multivariable logistic regression analyses were performed to assess the association between load-related parameters during gait (i.e., peak hip moment, hip moment impulse, and daily cumulative hip moment [product of hip moment impulse and mean steps/day]) and hip OA progression with and without adjustment for age, body weight, and minimum JSW. RESULTS: Of the 50 patients (47.4 ± 10.7 years old), 21 (42.0%) were classified into the progression group. The higher daily cumulative hip moment in the frontal plane at baseline was statistically significantly associated with radiographic progression of hip OA (adjusted odds ratio (OR) [95% confidence interval (CI)], 1.34 [1.06-1.70]; P = 0.013). The higher daily cumulative hip moment in the sagittal plane was also approaching significance in its association with hip OA progression (adjusted OR, 1.80 [0.99-3.26]; P = 0.052). CONCLUSIONS: In the female patients with secondary hip OA, higher daily cumulative hip moment, particularly in the frontal plane, was a predictor of radiographic progression of hip OA over 12 months. Reduction in daily cumulative hip moment by modification in gait and physical activity may potentially slow hip OA progression.

Functional performance of female patients more than 6 months after total hip arthroplasty shows greater improvement with weight-bearing exercise than with non-weight-bearing exercise. Randomized controlled trial.

BACKGROUND: Impaired functional performance and decreased muscle strength and muscle atrophy generally persist for a long period after total hip arthroplasty (THA). AIM: To investigate the effects of weight-bearing (WB) and non-weight-bearing (NWB) exercises on functional performance, Harris hip score (HHS), muscle strength and muscle thickness in women after THA. DESIGN: A randomised, controlled trial. SETTING: Community. POPULATION: Sixty-five women who had undergone unilateral or bilateral THA at least 6 months before enrolment in the study. METHODS: Participants were randomly allocated to the following groups: WB (n = 22), NWB (n = 21) and control (n = 22) groups. Participants in the WB and NWB groups performed daily home exercise programs for 8 weeks. Functional performance (timed up and go, sit-to-stand, stair climbing, walking speed and 3-min walk test), HHS, isometric muscle strength of the hip and knee muscle and gluteus and quadriceps muscle thickness were measured at baseline and after 8 weeks. RESULTS: An intention-to-treat analysis revealed that both the intervention groups exhibited significant improvements in almost all functional performance measures compared with the control group. Furthermore, the WB group showed significantly greater pre-post changes in the sit-to-stand and 3-min walk test compared with the NWB group. In terms of HHS, only the WB group showed significantly greater improvement compared with the control group. Relative to the control group, improvements in all isometric strength measures were observed in both the intervention groups. Significant improvement in quadriceps muscle thickness was observed in the WB group compared with the control group. However, no significant difference was observed among the three groups in pre-post changes in gluteus muscle thickness. CONCLUSION: WB and NWB home exercise programs were both effective for improving functional performance and muscle strength in women after THA. However, the WB exercise was more effective than the NWB exercise for improving sit-to-stand ability and walking endurance. CLINICAL REHABILITATION IMPACT: In this study, we demonstrated that the WB exercise was more effective than the NWB exercise for improving functional performance in patients after THA.