SummaryReasons for performing study Medial patellar ligament splitting (MPLS) has been shown to be a highly effective and minimally invasive treatment for upward fixation of the patella (UFP) in horses. However, long-term follow-up results of this procedure have not previously been reported. Objectives To evaluate the long-term resolution of UFP following MPLS and provide information on complications and recurrence. Study design Retrospective case series. Methods Data were collected from horses that underwent MPLS between 1999 and 2013. All cases had a confirmed diagnosis of UFP that had not responded to conservative therapy. Data were collected from medical records, including follow-up visits and through telephone conversations with the owner, trainer or referring veterinarian. Results A total of 85 horses were included. Fifty-eight horses (68%) had surgery under general anaesthesia in dorsal recumbency, while 27 horses (32%) underwent standing surgery and 97.6% had complete resolution of the UFP immediately after surgery or within the 2 week rehabilitation period. Two cases (2.4%) had only unilateral resolution after bilateral surgery, even after the procedure was repeated. The majority of cases (90.5%) were followed up at least 3 and up to 14 years after surgery. No short- or long-term complications were reported. No recurrence of UFP was observed in the horses that resumed exercise after surgery. Conclusions Medial patellar ligament splitting is a highly effective and minimally invasive surgical procedure to treat UFP when conservative treatment is unsuccessful. In addition, it allows for a very rapid return to sports activity. No short- or long-term complications were observed and no recurrence of this condition was noted.
