Superior check ligament desmotomy for treatment of superficial digital flexor tendonitis in Thoroughbred and Standardbred horses

Abstract

Bilateral superior check ligament desmotomy was performed on 31 Thoroughbred and 17 Standardbred horses as the sole method of treatment for superficial digital flexor tendonitis. Horses resumed racing between 6 and 19 months after surgery. Horses that were able to compete in 5 or more races without injury to the tendon again were considered to have had a successful return to racing. Twenty-five Thoroughbreds were suitable for later study and 13 of these (52%) raced on 5 or more occasions. Fifteen Standardbreds were suitable for later study and 10 of these (66%) raced on 5 or more occasions. Within the racing industry it is generally thought that about 20 to 30% of horses with superficial digital flexor tendonitis can return to racing after a prolonged rest. The results of this study suggest that bilateral superior check ligament desmotomy may improve the prognosis for a horse returning to racing after injury to the superficial digital flexor tendon.

Racing performance of Thoroughbreds with superficial digital flexor tendonitis treated with desmotomy of the accessory ligament of the superficial digital flexor tendon: 332 cases (1989–2003)

“…This increased the length of the check ligament-superficial digital flexor tendon unit (radius to second phalanx), by a finite amount and presumably shifts some of the load to the suspensory ligament, increasing the risk to that structure. Acute transient alteration of carpal anatomy with transection of the check ligament has been noted clinically, but no clinical evidence of carpal injuries in horses following SCLD has been documented 1,8,9,[11][12][13][14] and the carpal anatomy returns to normal within days after the surgery. Acute transient alteration of carpal anatomy with transection of the check ligament has been noted clinically, but no clinical evidence of carpal injuries in horses following SCLD has been documented 1,8,9,[11][12][13][14] and the carpal anatomy returns to normal within days after the surgery.…”

“…An Australian study 13 demonstrated an improvement in rate of return to racing (≥ 2 starts) in horses that underwent SCLD, compared with nonsurgical treatment. Standardbred racehorses with SDFT treated with SCLD have also been reported to have a more favorable prognosis than Thoroughbreds for return to racing and performance.…”

Autologous bone marrow aspirate for treatment of superficial digital flexor tendonitis in 105 racehorses

“…DAL-SDFT results in increased strain on the SDFT in vitro, and is reported to increase the risk of suspensory desmitis in the treated limb in Thoroughbred racehorses (Hogan and Bramlage 1995). However, it has been used with reasonable success, with between 52 per cent and 82 per cent of treated horses returning to race at least five times without re-injury (Ordidge and others 1996, Fulton and others 1994, Hogan and Bramlage 1995, Gibson and others 1997, Alexander and others 2001, Hu and Bramlage 2014). …”

Proximal Check Ligament Desmotomy

“…[4][5][6]9 The reason for improvement is not clearly understood but is likely related to the functional lengthening of the superficial digital flexor musculotendinous unit that occurs after desmotomy. When the proximal check ligament is intact, the majority of the load during weight bearing is sustained by the tendon from the proximal check ligament distally.…”

“…2,3 When performed for superficial digital flexor tendonitis, the prognosis for a return to racing appears to be improved for racehorses, with Standardbreds showing greater improvement. [4][5][6] COMPLICATIONS Seroma formation is the most common complication. Seromas should be left to resorb spontaneously.…”