Stance and weight distribution after tibial plateau leveling osteotomy in forelimb and hind limb amputee dogs

Published: Small Animal Orthopedics, Koret School of Veterinary Medicine, Rehovot, Israel. The Hebrew University of Jerusalem, P.O Box 12, 76100 Rehovot, Israel

Keyword: Dog, amputation, tibial plateau leveling, TPLO, weight distribution, stance analyzer

Author(s): Ron Ben-Amotz, David Dycus, David Levine, Andréia Gonçalves Arruda, Nicholas Fagan and Denis Marcellin-Little

Overview:  The objectives of the current study were to measure the weight distribution and posture of forelimb and hind limb amputee dogs after a TPLO (AmpTPLO), to compare those to weight distribution and posture in amputee dogs not undergoing a TPLO (Amp), and to four legged dogs after a TPLO (4LTPLO).

Materials/Methods:

• Twenty-eight dogs were enrolled in the study: Seven AmpTPLO, 10 Amp, and 11 4LTPLO.
• All dogs had undergone either a forequarter amputation or a coxofemoral disarticulation at least eight weeks or more prior to being enrolled in the study.
• No meniscal injuries were identified during TPLO surgery.
• TPLO were stabilized with a bone plate and a combination of locking and nonlocking screws.
• Craniocaudal and mediolateral stifle radiographs were acquired before surgery, immediately after surgery, and eight weeks or more after surgery.
• Standing weight distribution was measured using the Companion Stance Analyzer.
• Fifteen measurements of weight distribution were recorded and means were calculated for each patient.
• Shoulder, elbow, carpus, hip, stifle, and tarsus angles were measured.

Results: 

• Dogs with a previous hind limb amputation had the largest mean increase in weight bearing in the contralateral thoracic limb.
• The AmpTPLO increased the weight placed on their ipsilateral thoracic limb.
• In contrast to four-legged control dogs, which bear 60% of their weight in the forelimbs and 40% in the hind limbs, dogs bear 74% of their weight on their thoracic limbs and 26% on their pelvic limbs after a hind limb amputation.
• In the current study, AmpTPLO appear to behave similarly to those Amp with regards to thoracic limb weight distribution.

Conclusions:  The position of the center of mass and posture of AmpTPLO and Amp does not differ. The weight distribution and posture of Amp is not impacted negatively by TPLO.