Kinetic, kinematic, magnetic resonance and owner evaluation of dogs before and after the amputation of a hind limb

BACKGROUND The amputation of a limb is a surgical procedure that is regularly performed in small animal practice. In spite of several clinical reports indicating high owner satisfaction after limb amputation in dogs, an amputation is still very critically seen by the owners, and even by some veterinarians, due to the lack of accurate information about the recovery of amputee patients. Thus, the objective of this study was to prospectively evaluate, both objectively and subjectively, the recovery outcome of dogs undergoing a hind limb amputation. Twelve patients in which a hind limb amputation was scheduled were studied. Kinetic and kinematic gait analyses were performed before the amputation, and 10, 30, 90 and 120 days after surgery. Magnetic resonance (MR) examination of the contralateral stifle joint was performed before and 120 days after amputation. The subjective impressions of the owners were gathered at the same examination times of the gait analyses. RESULTS Kinetic data showed a redistribution of the load to all remaining limbs after the amputation; ten days after the procedure patients had already established their new locomotory pattern. Kinematic data showed significant differences between sessions in the mean angle progression curves of almost all analyzed joints; however, the ranges of motion were very similar before and after the amputation, and remained constant in the subsequent sessions after the amputation. No changes in the signal intensity of the soft tissues evaluated, and no evidence of cartilage damage or osteoarthritis was seen on the MR examination of the contralateral stifle. Owners evaluated the results of the amputation very positively, both during and at the end of the study. CONCLUSIONS Dogs had a quick adaptation after a hind limb amputation, and the adaptation process began before the amputation was performed. This happened without evidence of morphologic changes in the contralateral stifle joint, and with a very positive evaluation from the owner.