Computer-based gait analysis of dogs: evaluation of kinetic and kinematic parameters after cemented and cementless total hip replacement.

To date it is unclear whether cementless total hip replacement (THR) in dogs is of clinical advantage in comparison to cemented THR with regard to lameness improvement. Thus the aim of this study was to compare objectively the development of the gait pattern after cemented and cementless THR in dogs. For this purpose, 18 adult dogs with hip dysplasia underwent computer-based gait analysis on an instrumented treadmill prior to unilateral THR and then again ten days, four weeks and four months after surgery. Analysed kinetic parameters were symmetry indices (SI) of vertical ground reaction forces (GRF), which included peak vertical forces (PFz), mean vertical forces (MFz), vertical impulse (IFz), and vertical ground reaction forces of the arthroplasty limbs only. Analysed kinematic parameters were range-of-motion and the flexion and extension angles of hip, stifle and hock joints. The symmetry indice for PVF, MFz and IFz decreased to a value less than six in both THR groups four months after surgery, which is defined as not lame. Improvement in lameness of the arthroplasty limbs during the examination period of four months was not significantly different between the cemented and cementless groups. The results suggest that within a short-term observation period of four months after surgery, neither cementless nor cemented THR have a greater advantage with regard to lameness improvement. Additional studies with larger pools of subjects and longer time periods for follow-up examinations are necessary to verify these findings.

Computer-assisted gait analysis of the dog: comparison of two surgical techniques for the ruptured cranial cruciate ligament.

OBJECTIVES: To compare the improvement in degree of lameness following surgical repair of cranial cruciate ligament rupture in dogs using computer-assisted gait analysis. METHODS: Two groups of 14 dogs were used. One group was treated by a capsular-fascial imbrication method, and the other group by tibial plateau levelling osteotomy (TPLO). All dogs underwent gait analysis prior to surgery, as well as at four days, four weeks, and four months after surgery. Symmetry indices of vertical ground reaction forces as well as vertical ground reaction forces in % body weight, joint angles and certain gait cycle parameters were evaluated. RESULTS: Four months after surgery, the degree of lameness expressed as symmetry index for peak vertical force for the TPLO group (5.83%) was not significantly different to the capsular-fascial imbrication group (19.05%). Within the TPLO group, there was a significantly increased ability to extend the stifle joint four months after surgery. The stifle motion pattern of the capsular-fascial imbrication group as well as the range-of-motion in both groups showed very little change at the time of the last gait analysis. The complication rate was greater in the TPLO group than in the capsular-fascial group. CLINICAL SIGNIFICANCE: In conclusion the results suggest that the TPLO method leads to a faster recovery and improved limb function in comparison to the capsular-fascial imbrication method four months after surgery. Further analyses are needed to determine if the TPLO method is superior concerning long-term joint stability.