AUTHOR=Török Magdaléna , Dvoranová Mária , Lipták Tomáš , Mad'ari Aladár , Kuricová Mária TITLE=Structured therapeutic exercise program effect on PROM and muscle mass in dogs with osteoarthritis: a prospective clinical study JOURNAL=Frontiers in Veterinary Science VOLUME=Volume 13 - 2026 YEAR=2026 URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2026.1836746 DOI=10.3389/fvets.2026.1836746 ISSN=2297-1769 ABSTRACT=BackgroundDegenerative joint disease, namely osteoarthritis, represents a major cause of chronic pain and functional limitation in dogs. Although rehabilitation is widely incorporated into clinical management, objective data quantifying joint mobility and muscular adaptations following structured exercise protocols remain limited.ObjectiveTo evaluate changes in passive range of joint motion (PROM) and limb circumference following a five-week therapeutic exercise program in dogs diagnosed with degenerative joint disease.MethodsTwenty-one client-owned dogs underwent a standardized rehabilitation protocol consisting of three sessions per week. Goniometric measurements of appendicular joints and limb circumference assessments were performed before and after intervention. Deviations from published reference midpoints were calculated, and improvement in joint motion was defined as reduction in deviation regardless of direction of absolute change. Morphometric parameters were also recorded. Joints were analyzed individually to describe distribution of changes across the cohort.ResultsAcross most joints, extension movements were associated with a higher proportion of PROM increases, whereas flexion showed a more mixed pattern with frequent decreases or unchanged values. The most pronounced response was observed in the hip joint. Pelvic limb musculature showed greater circumference than thoracic limb musculature, with the largest mean increase in circumference recorded in the thigh region. Body weight and trunk circumferences remained largely stable during the intervention period. Considerable inter-individual variability in response to therapy was observed.ConclusionA structured exercise-based rehabilitation program was associated with measurable changes in goniometry and muscle circumference in dogs with secondary degenerative joint disease. These findings support the integration of targeted therapeutic exercise into multimodal conservative management strategies for orthopedic patients.