Bowed tendons, like all tendon and ligament injuries, are serious injuries which must be treated as soon as possible and as thoroughly as possible. These injuries are caused by excessive strain on the tendon, usually caused by exercise. During exercise a tendon can become stretched to the point of tearing if the muscles surrounding it are not strong enough to support it, the footing is too deep or the horse's hoof is too flat and causes the back of the leg to stretch. A bowed tendon gets it’s ‘banana’ shape from tears in the tendon causing swelling at the point of the tear. In extreme cases the tendon may actually be severed. If you suspect that your horse has a bowed tendon contact your vet immediately.
The most characteristic symptom of a bowed tendon is the ‘banana’ shape mentioned above. When fibres in the tendon tear they become misshapen and irregular. The area will become swollen, resulting in a rounded protruding lump on the tendon. This lump will not be superficially on top of the tendon, like a bruise, it will be from within the tendon. This can be detected by feeling the tendon from top to bottom; the bow will feel hot but reasonably hard and not malleable. Any bumps on the tendon, weather bruising or tears, should be examined by a vet. The vet should feel the tendon and palpate the injury. An ultrasound is recommended for the best diagnosis. The price of an ultrasound varies, but the norm is between $40 and $150.
Lameness often, if not always, accompanies bowed tendons. The degree of lameness is not indicative of the extent of the injury. A very lame horse might not have done that much damage to the tendon, and a horse which only shows slight lameness/soreness might actually have severe tearing. For this reason it is important to monitor you horse’s movements and habits, especially since bowed tendons might appear up to 48 hours after the trauma which caused them. So called 'bandage bows' are believed to be caused by improperly applied polo wraps or bandages, however in most cases the bow was caused by overexertion and only manifested itself later.
Traditional treatments include cold therapy, rest, poultices/braces, and alternating hot and cold compresses. These are all still recommended by vets today, and are usually effective at bringing down swelling. The benefit of these treatments is that they do the horse no harm. The same cannot be said of pinfiring (thermocautery), which is painful to the horse and actually weakens the horse’s tendons and ligaments by replacing healthy tissue with scar tissue. This involves applying hot metal to the injury, either as a flat bar on the surface or pressed into the skin (‘pins’). It is commonly practiced at the racetrack; however it is losing popularity.
Recent advances in veterinary care have resulted in new treatments for bowed tendons. Many products are available which provide circulating cold water and keep the affected leg cool for hours. More recently shockwave therapy has been used to much success. This treatment is best used when the acute stage of the injury is over and the swelling has subsided. Shockwave therapy is expensive (on average $300 per treatment), but has been shown to be highly effective in treating old bowed tendons, ligament injuries, and arthritis.
While traditionally a bowed tendon would mean the end of a horse’s career, with today’s veterinary care a horse can return to work at the same level as before the injury. This requires time, dedication, and a bit of luck. It is hard to determine the outcome of a bowed tendon months or even years after the initial injury. Some horses are sound with just cold therapy and lots of rest, while others undergo thousands of dollars worth of treatment and never fully recover. With this type of injury only time will tell, and the healing of any tendon injury should never be rushed.
When a horse is going to be exercised it's legs should be supported, particularly if it is going to be worked at a fast pace or in deep footing. This is very important if the horse has already suffered from a bowed tendon. Polo wraps, tendon boots, and support wraps are all good options and vary in cost. After exercise feel for heat in all legs, especially the front. Applying cold to the legs helps reduce swelling and the likelyhood of injury. This can often be done by hosing the legs with cold water for about 10 minutes. Good shoeing and farriery is also important in balancing the horse's leg and preventing stress on the tendons ( horse-care.suite101.com/article.cfm/equine_health_hoof_care).The best way to prevent bowed tendons is to develop an exercise program which will gradually get the horse fit rather than stress it too early.