Scintigraphic evaluation of TPLO and CTWO in canine osteoarthritis.

The objective of this study was to evaluate the bone uptake of the bone-seeking radionuclide (99m)technetium-methylene diphosphonate ((99m)Tc-MDP) in order to examine and compare the clinical efficacies of tibial plateau leveling osteotomy (TPLO) and cranial tibial wedge osteotomy (CTWO) for the correction of experimentally induced cranial cruciate ligament (CrCL) transected stifle. Fifteen healthy adult beagle dogs, weighing between 10 and 15 kg, were used for this study. Dogs were assigned to TPLO (n=5), CTWO (n=5) or a control sham group (n =5) and screened with both physical and complete orthopedic examinations. Left CrCLs were transected and two of the three groups were stabilized using TPLO and CTWO. Scintigraphic evaluation of the stifle was performed before TPLO or CTWO surgical repair of the left limb and again at 4, 8 and 12 weeks after surgery. Bone uptake values at 8 and 12 weeks for the TPLO and CTWO groups were not significantly different from their preoperative values, but these differed significantly from the control group at 4, 8 and 12 weeks (p<0.01). No significant differences were found between TPLO and CTWO values. In summary, the relative efficacy of CTWO approximately equals that of TPLO. Moreover, the results of this study confirmed that TPLO and CTWO inhibited the progression of osteoarthritis in CrCL-deficient dogs.