Imaging predictors of short term clinical response to osteopathic manipulative treatment in patients with knee osteoarthritis.

Abstract

Pain accompanied by joint dysfunction is common during the progression of knee osteoarthritis. Osteopathic manipulative treatment (OMT), a manual therapy technique, is increasingly used to alleviate knee osteoarthritis symptoms. However, predictors of treatment response to OMT remain poorly understood. This study aimed to examine (1) short-term changes in pain, function, and lower-limb alignment following OMT intervention, (2) baseline factors predictive of symptom improvement after OMT. In this prospective observational study, participants received a standardized OMT protocol twice weekly for two weeks, with no other concurrent interventions. Outcomes included the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and 12-items Short Form Health Survey (SF-12) assessed at baseline and two weeks. Standing full-leg radiographs were obtained at both time points to measure coronal and sagittal alignment angles, including the hip-knee-ankle angle, joint-line convergence angle, and sagittal hip-knee-ankle angle. Changes from baseline to post-treatment were analyzed using paired t-tests. The reliability of radiographic measurements was evaluated in a subset of images via duplicate independent assessments, calculating the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable change at 95% confidence (MDC95). Multiple linear regression was performed to identify baseline predictors of WOMAC improvement, adjusting for demographic variables, symptom duration, baseline WOMAC and SF-12 scores, Kellgren-Lawrence grade, and baseline alignment parameters. Among 128 participants, the WOMAC score decreased by a mean of 18.31 points and the SF-12 score increased by 27.56 points after two weeks. Higher baseline WOMAC scores predicted greater improvement, whereas longer symptom duration predicted less improvement. The difference in the sagittal hip-knee-ankle angle before and after the intervention was statistically significant, with an increase of 2.03° post-intervention. Radiographic measurement reliability was excellent at both time points, baseline (ICC = 0.968, 95% CI 0.941-0.983; SEM = 0.555°; MDC95 = 1.539°) and post-treatment (ICC = 0.985, 95% CI 0.975-0.993; SEM = 0.519°; MDC95 = 1.440°). Short term improvements in symptoms, function, and health related quality of life were observed following two weeks of standardized osteopathic manipulative treatment in patients with knee osteoarthritis. Greater baseline symptom severity and shorter symptom duration were independently associated with greater improvement in WOMAC scores, whereas most baseline radiographic parameters showed limited independent predictive value. The observed change in sagittal knee alignment is more likely to reflect a short term functional or postural adaptation than structural remodeling.Clinical trial registration: ChiCTR2300074433, http://www.chictr.org.cn/, August 2023.