Objective The aim of this study was to report on complications and outcomes with repair of ruptured canine patellar tendons using primary tenorrhaphy coupled with patellar tendon allograft transplantation and use of a transarticular external skeletal fixator. Materials and Methods This report includes three dogs with acutely ruptured patellar tendons, all of whom had surgical repair using a patellar tendon allograft. Dogs were assessed postoperatively by physical examination, owner input, and/or video review. Functional outcomes were classified as full, acceptable, or unacceptable based on previously established criteria. Results Follow-up time was between 24 and 46 weeks. Two dogs obtained full function and one dog reached acceptable function. The acrylic connecting bars of the external fixator fractured and needed to be replaced in one dog. There were no other problems or complications. There was no evidence of rejection of any allograft. Clinical Significance Primary tenorrhaphy supported by patellar tendon allograft transplantation and transarticular skeletal fixation appears to be a viable option without evidence of patellar tendon allograft rejection and acceptable or full recovery in the three dogs of this report.

Background: Achilles mechanism rupture is a surgical condition involving primary tenorrhaphy with various described means of surgical augmentation and bolstering. Aim: To report complications and outcomes with a novel Achilles repair technique in dogs using a superficial digital flexor tendon (SDFT) or deep digital flexor tendon (DDFT) allograft. Methods: Medical records were reviewed for dogs with chronic rupture or deterioration of the Achilles mechanism. Fibrous tissue was excised and either primary tenorrhaphy or reattachment of the tendon(s) to the calcaneus were performed. The surgical repair was supplemented by a SDFT or DDFT allograft, and post-operative immobilization was provided using a transarticular hybrid External Skeletal Fixator (ESF). Complications were classified as minor, major, or catastrophic, and function was classified as full, acceptable, or unacceptable based on established guidelines. Results: Complications occurred with 6 of 12 repairs including 1 minor, 6 major, and 2 catastrophic complications. The two catastrophic complications were recurrence of tarsal hyperflexion and lameness at 20 weeks and 18 months following surgery. Of the 12 surgeries performed, 2 resulted in full function, 8 with acceptable function, and 2 with unacceptable function at last follow-up 17 - 98 weeks post-surgery (mean 45 weeks) for a success rate of 10/12 cases. Conclusion: The use of SDFT or DDFT allografts, coupled with an external fixator, can provide a moderate rate of full or acceptable functional outcomes and appears a viable treatment. However, complications were frequent and without a comparison group no conclusions can be drawn about the inferiority or superiority of this technique to other techniques for Achilles mechanism repair in dogs.