Change in tibial plateau angle after tibial plateau leveling osteotomy in dogs.

OBJECTIVE

To determine the change in tibial plateau angle (TPA) during healing after tibial plateau leveling osteotomy (TPLO) performed for cranial cruciate ligament insufficiency in dogs and to examine factors that may be associated with the change.

STUDY DESIGN

Retrospective study.

STUDY POPULATION

One hundred and forty-nine canine stifles after TPLO procedure.

METHODS

Records of dogs that had TPLO were reviewed. Patient age, weight, sex, breed, pre- and postoperative TPA, recheck TPA, time to recheck, type of implant used, and radiographic evidence of healing were analyzed.

RESULTS

Mean time to recheck evaluation was 46 days (range, 28-65 days). Mean difference between immediate postoperative and recheck TPA measurements was 1.5 degrees (range, -3 to 9 degrees). Recheck TPA was a significantly greater (numerically higher) than immediate postoperative TPA (P<.0001). There was no significant effect of patient weight, type of plate used, or healing status of the osteotomy at the time of recheck. No correlation between pre- or postoperative TPA angles and change in TPA angle was detected.

CONCLUSIONS

TPA changes during osteotomy healing after TPLO, but factors influencing this change were not identified.

CLINICAL RELEVANCE

TPA may increase during healing after TPLO despite apparently adequate osteotomy fixation. The clinical relevance of this increase is unknown but is likely minimal.