Texas Equine Veterinary Association

www.teva-online.org • Page 13 the patient is tractable for appropriate bandaging and exercise for the first three months post surgery. There is variation in the amount of exercise allowable depending on the condition of the feet. With conventional surgical descriptions a medial approach is often described; in my experience this approach requires significantly more dissection and there is a higher likelihood of a blemish as a result. I personally find a blemish on the medial aspect of the limb as offensive as on the lateral. The most straight forward technique and commonly performed technique is accomplished using conventional surgery in lateral recumbency positioned for a lateral approach, with the affected leg up. The skin may be rolled palmarly prior to incising so the final placement appears over the fourth metacarpal bone. The skin incision begins two cm distal to the head of the fourth metacarpal bone and extends distally two cm. Sharp dissection is continued through the subcutaneous tissue, the fascia of the flexor carpal sheath and paratenon, exposing the junction of the accessory (inferior check) ligament with the DDFT. A pair of curved hemostats are passed along the dorsal border of the accessory ligament and the DDFT spread, then withdrawn. Next, the hemostats are passed along the palmar border of the ligament in a similar fashion. Care must be taken to avoid the neurovascular bundle along the medial aspect of the limb. Digital palpation of the SDFT and DDFT is performed to confirm that the proper structure has been isolated. The lower limb may be slightly flexed to relax the ligament which is isolated, exposed and exteriorized with the hemostatic forceps, and then transected. I generally remove a one cm section of the ligament, although removal of this section is not necessary, requires more tissue dissection, and the second transecting cut can be difficult to accomplish neatly. The limb should undergo extension and flexion and the operator should observe the movement of the structure to assure complete transection. Closure should be performed in three layers being careful to leave a half cm opening in the distal portion of each layer to allow for drainage should a seroma occur. The bandage should extend above the knee and be taped to prevent slippage and exposure of the incision. If there is no slipping of the bandage, the first bandage should remain in place four to five days before changing. The foot should be trimmed appropriately and if a corrective device such as a toe cap is needed, it should be applied. I routinely administer two to three days of oxytetracycline (44 mg/kg IV SID) in addition to a NSAID in the post-operative period to encourage loading the foot. Deep digital flexor tenotomy may be performed for stage two deformities. As a general rule, even with severe deformities, I attempt correction with a check ligament desmotomy prior to this. Mid-metacarpal or mid-pastern tenotomy is acceptable, but greater release is achieved with a mid-pastern approach and is my preferred technique in adults which suffer repeat abscessation or septic osteitis of the distal phalanx. Reports vary regarding the level of success after surgical intervention. In general, soundness is achieved but racetrack performance is decreased from that of unaffected siblings. Although clubfoot deformity in horses is common there is a sparse amount of evidence-based work defining the syndrome and its management. Therapy is often empirical and based on clinical experience. The primary goal of therapy and management of any clubfoot horse is to obtain a sound horse with a normal or near normal foot which will be maintained with routine hoof care. One important principle of clinical management is to determine if discomfort or lameness is present, and if so, to localize the source of the lameness and determine the association of the lameness to the club foot (primary or secondary). If the foot is improperly loaded, a normal contour hoof capsule will not be possible to obtain and the underlying lameness may be the limiting factor on the future athletic capacity. a. BaytrilTM, Bayer Healthcare LLC, Animal Health Division, Shawnee Mission, KS 66201 sUggested reading Auer JA. Flexural Deformities. In: Auer JA, ed. Equine Surgery. Philadelphia: W.B. Saudners Company, 1992;957-71. Baxter GM, Stashak TS, Hill C. Conformation and Movement. In: Baxter, GM, ed. Adams and Stashak's Lameness in horses 6th ed. West Sussex: Blackwell Publishing, Ltd., 2011;73-108. Greet TRC. Managing flexural and angular limb deformities: The Newmarket perspective, in Proceedings. Am Assoc Equine Pract 2000;46;130-136 Hunt RJ. Flexural limb deformities in foals. In: Ross MW, Dyson SJ, eds. Diagnosis and Management of Lameness in the Horse, 2nd ed. St. Louis: Elsevier Saunders, 2011;645-649. Madison JB, Garber JL, Rice B, et al. Effects of oxytetracycline on metacarpophalangeal and distal interphalangeal joint angles in new born foals. J Am Vet Med Ass 1994;204:240-240. O'Grady SE. Flexural deformities of the distal interphalangeal joint (clubfeet) – a review. Equine vet Educ 2012 Stone WC, Merritt K. A review of the etiology, treatment and a new approach to club feet, in Proceedings. Am Assoc Equine Pract Focus on the Equine Foot. 2009 Walmsley EA, Anderson GA, Adkins AR. Retrospective study of outcome following desmotomy of the accessory ligament of the deep digital flexor tendon for type 1 flexural deformity in Thoroughbreds. Australian Vet J 2011;89(9):265-268. White NA. Ultrasound-Guided Transection of the Accessory Ligament of the Deep Digital Flexor Muscle (Distal Check Ligament Desmotomy) in Horses. Vet Surg 1995;24:373-378. Caldwell FJ, Waguespack RW. Evaluation of a Tenoscopic Approach for Desmotomy of the Accessory Ligament of the Deep Digital Flexor Tendon in Horses. Vet Surg 2011;40: 266-71. Yiannikouris S, Schneider RK, Sampson SN, et al. Desmotomy of the Accessory Ligament of the Deep Digital Flexor Tendon in the Forelimb of 24 Horses 2 Years and Older. Vet Surg 2011;40:272- 276.

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