To evaluate the feasibility and limitations associated with a minimally invasive ultrasound-assisted cutting thread technique for tenotomy of the deep digital flexor tendon (DDFT) in horses. Ex vivo study. Twenty cadaveric forelimbs. Forelimbs were placed on a jig to mimic a standing semiflexed position and the midmetacarpal region was prepared to perform tenotomy of the DDFT using a percutaneous technique with a cutting thread. For that purpose, the thread was placed percutaneously around the DDFT (first dorsally and then palmarly) with the aid of a curved 20 gauge spinal needle. Tendon palpation/manipulation and ultrasonographic assessment assisted thread placement. Procedure time and skin puncture size were recorded. Limbs were then dissected to evaluate the degree of DDFT transection and the presence of any iatrogenic lesions. The DDFT was completely transected in all cases. Minor lesions of the superficial digital flexor tendon were found in 11/20 limbs and considered clinically irrelevant. However, the neurovascular bundle was damaged in 6/20 limbs (four limbs had nerve damage and two limbs had a nerve and either a palmar artery or vein damaged). The skin puncture hole sizes ranged from undetectable to 5 mm long. The average duration of the procedure was 7 min and 38 s (range: 4 min 56 s to 10 min 19 s). A DDFT tenotomy can be performed reliably with a percutaneous cutting thread technique. However, refinement of the technique is required to minimize iatrogenic damage. The reported technique allows a DDFT tenotomy to be performed in a minimally invasive manner and has the potential to be clinically applicable.