Injuries to the structures within the digital flexor tendon sheath (DFTS) can be the primarycause of non-infectious tenosynovitis, for which diagnostic and therapeutic tenoscopy canbe performed. In this retrospective study, the medical records of fifty horses that underwenttenoscopic treatment of non-infectious tenosynovitis of the DFTS from 2008 to 2016 at theFaculty of Veterinary Medicine (Ghent University), were evaluated. Telephonic follow-up informationwas obtained for forty horses.In jumping horses, front limbs were significantly more often involved, whereas in non-jumpinghorses, the hind limbs were affected more frequently (P=0.01). Lesions of the deep digitalflexor tendon (DDFT) were observed in 45% of the cases and lesions of the manica flexoria (MF)in 39% of the cases. Ultimately, 27.7% of horses with lesions of the DDFT and 53% of horses withlesions of the MF returned to their original level of performance, with a mean follow-up periodof 4.6 ± 2.5 years.