Nonseptic tenosynovitis of the digital flexor tendon sheath caused by longitudinal tears in the digital flexor tendons: a retrospective study of 135 tenoscopic procedures

To determine the prevalence of LTs of the digital flexor tendons in a large population of horses undergoing diagnostic tenoscopy of the DFTS and to assess the outcome of surgical treatment and the factors influencing the outcome. Methods: Medical records of 130 horses with chronic tenosynovitis of the DFTS that had tenoscopic surgery between 1999 and 2009 were evaluated. One hundred and thirty-five DFTSs were examined. LTs were diagnosed in 104 DFTSs in 101 horses and long-term follow-up was obtained. Results: Seventy-eight percent of the horses with a nonseptic tenosynovitis of the DFTS had a LT. Preoperative ultrasonographic examination diagnosed tears in 76% of the cases. In showjumpers forelimbs were more frequently affected than hindlimbs (88 vs. 12%), with the right front having a higher incidence of injury than the left front (76 vs. 24%). Seventy-nine percent of the tears involved the deep digital flexor tendon (DDFT) and 87% were located on the lateral tendon border. Thirty-seven horses (38%) returned to an equal or higher level of work. The use of a radiofrequency probe (coblation) was associated with a lower level of performance and decreased the cosmetic end result. Persistence of marked post operative distension of the DFTS carried a poor prognosis for return to previous level of work. Conclusions and potential relevance: A guarded prognosis for future soundness should be given to horses presented for treatment of LTs of the digital flexor tendons. The use of coblation wands had a negative effect on the final outcome