Tendinopathy and desmopathy are significant causes of morbidity in horses./r/nTo evaluate the use of percutaneous ultrasonic debridement (PUD) as a treatment for chronic tendinopathy and desmopathy in the horse./r/nEight adult horses with 10 affected limbs presented for lameness, ranging from 60-700 days postinjury. Diagnostic ultrasound identified the following: suspensory branch desmitis ( = 1), suspensory body desmitis ( = 2), Achilles tendinopathy ( = 1), desmitis of the accessory ligament of the deep digital flexor (DDF) tendon ( = 1), DDF tendinopathy ( = 2), and superficial digital flexor tendinopathy ( = 3). All horses had demonstrated lameness ranging from grade 1 to 4 [American Association of Equine Practitioners (AAEP) scale], with a mean pretreatment grade of 2.7. All horses underwent PUD using the Tenex Health TX System./r/nFollow-up results were available from 6 to 41 months (mean, 23.2 months). Follow-up ultrasound imaging demonstrated improvement in fiber alignment and architectural change in all cases. All horses had a reduction in lameness from the treated tendon or ligament (AAEP grade 0-1; mean AAEP grade, 0.2) following a single treatment; lameness completely resolved in 8 of 10 treated limbs. No adverse events occurred in any case. No horses in this study developed a recurrence of their original lesion./r/nHorses in this study demonstrated improvement following the PUD procedure. The procedure was well-tolerated and safe. Removal of tendinopathic scar tissue with PUD resulted in a return to function and without recurrence of the original lesion in all horses.