Characterization of Weight-bearing Compensation in Dogs With Bilateral Hip Osteoarthritis

To describe the weight-bearing compensation in working dogs with bilateral hip osteoarthritis (OA), 50 police working dogs were evaluated with a weight distribution platform at the initial evaluation and after intra-articular treatment (a negative control - 0.9% sodium chloride (NaCl), a platelet concentrate, Hylan G-F 20, triamcinolone hexacetonide or stanozolol). Six evaluation sessions were performed, over a 180-day period. Results were compared by breed, age, sex, weight and Orthopedic Foundation for Animals hip grade scores with the Independent Samples T-Test, repeated samples Analysis of variance and Pearson correlation coefficient, P < .05. Animals had a mean age of 6.5 ± 2.4 years and a bodyweight of 26.7 ± 5.2kg. No significant differences were observed when comparing weight-bearing for different breeds, sex, hip grades or weight during the initial evaluation. Significant differences were observed in deviation (P < .01) and symmetry index (P < .01) between the control and treatment groups during the follow-up period. A weight shift from pelvic to thoracic limbs was observed, with a weak, although a significant, correlation between a pelvic limb and the opposing contralateral thoracic limb. Labrador Retrievers showed higher symmetry index and deviation from normal values during the follow-up period than German Shepherd Dogs and Dutch Shepherd Dogs. Male dogs also showed higher symmetry index and deviation compared with females. At this period, the symmetry index showed a weak, although significant, correlation with body weight. Weight-bearing of all limbs correlated with the remaining limbs, reflecting a more balanced weight distribution than the initial evaluation. The weight distribution platform can be used to evaluate patients, at the initial presentation and during the assessment of response to treatment.