Prevalence and response to surgical treatment of lateral palmar intercarpal ligament avulsion in horses: 37 cases (1990-2001)

OBJECTIVE: To clarify the diagnosis of avulsion of the lateral palmar intercarpal ligament (LPICL), correlate avulsion of this ligament with lameness, determine the prevalence of avulsion of the LPICL in a hospital population, and evaluate the response to surgical removal of the avulsion fragment in horses. DESIGN: Retrospective study. ANIMALS: 37 horses with avulsion of the LPICL. PROCEDURE: Medical records and radiographs of horses with avulsion of the LPICL were reviewed; follow-up information was obtained from race records and from owners via a telephone survey. RESULTS: Of 6,418 horses evaluated for forelimb lameness from March 1, 1990, to December 31, 2001, 37 (0.5%) had avulsion of the LPICL; each horse had a discrete fragment associated with avulsion of the ligament origin from the ulnar carpal bone. Twenty-six horses underwent arthroscopic fragment removal; 20 of 22 (91%) horses for which follow-up information was available returned to work. Of 9 horses treated conservatively, 5 returned to work. Odds ratio calculations indicated that horses treated surgically were 8 times as likely to return to work than those not treated surgically. Twelve horses had LPICL avulsion without concurrent osteochondral fragmentation in the same or additional joints; follow-up information was available for 9 of those horses, of which 8 returned to athletic work. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, discrete avulsion of the LPICL can be a cause of lameness and arthroscopic debridement may be the treatment of choice. Prognosis for return to work of horses with avulsion of the LPICL is good.