Vet Rich Forfa on Bowed Tendon

Tendonitis is inflammation of the tendon structures and is the result of a physical weight bearing strain overload by the soft tissue support of the lower limbs of horses.

A “bowed” tendon is a term used to describe an injury to a tendon which may manifest a bowed appearance.

Bowed tendons most commonly occur in the front legs. The injury can occur due to fetlock overextension when a horse’s weight is on one leg. Poor foot conformation, long toes or low heels, improper conditioning of the horse, working an unfit or fatigued horse, and poor, uneven or slippery ground surfaces, can all contribute to tendon strain. Horses with less demanding exercise regimes are less likely to develop a tendon injury.The superficial digital flexor tendon is the most commonly affected and the middle or mid-cannon location is most common. Also the deep digital flexor tendon, check ligament or suspensory ligament can be injured alone or in combination.  The diagnosis of tendonitis can be made by a physical examination and an adequate medical history. Signs of an acute tendon injury are swelling, heat, and pain on palpation of the affected area. If the injury is minor, swelling may not be obvious and the degree of lameness may be minor or subtle. In cases of a greater severity the horse will be moderately to severely lame with greater tendon swelling.

Ultrasound examination is used to document the extent of the injury, to form a prognosis and to follow healing after treatment. A scale and grading system is used to describe the severity of the lesion, which can be followed by serial ultrasound exams. Tendon injuries are serious so if one is suspected the horse needs to be examined by your veterinarian.

Initial acute treatments would be cold water or ice water applications for the first 24 hours, anti-inflammatory medications and support wraps applied in a proper manner. Stall rest is critical to obtaining the best success.

Other therapies are extracorporeal shock wave, stem cell therapy injection, I-Rap injections, and purified protein derivative injections into the lesion on the affected tendon. All these therapies reduce the effects caused by hemorrhage, inflammatory cells and chemical mediators which can complicate the tendon’s healing.

Rehabilitation includes an initial period of extended stall rest dependent upon severity of the injury to the tendon followed by controlled exercise such as hand walking on a lead or walking under tack.  Every effort should be made to prevent re-injury to the tendon.  Do not be in a hurry!  Follow up ultrasound scans made by your veterinarian can document when your horse will be ready to resume his normal work program.

Prognosis for return to the same level of work depends on the severity of the original injury. If disruption to the fibers of the tendon was minimal and the tendon healed rapidly the prognosis is better of working at the same level. With more severe the injury the more aggressive therapies are recommended. About 70% of horses can be expected to recover completely and return to the same level of work, the others usually can recover to be sound and work at a less strenuous level.

Proper trimming and shoeing by a good farrier, conditioning your horse so it is fit for the work it does and examining the legs after a hard work can go a long way to preventing tendon injuries.

Rich Forfa, DVM, Dip.ABVP

Monocacy Equine Veterinary Associates
P.O. Box 155
Beallsville, MD 20839
www.monocacyequine.com