I was checking a friends mare for lameness earlier today and said “the windgall on the near hind is harder and more swollen than the off hind” or words to that effect. I was horrified that not a dingle person, out of the five horsey people there, knew what a windgall is.
So here’s my explanation.
A windgall is a wear and tear injury, which is quite common in working horses, and is usually of no problem and doesn’t cause lameness, except for looking unsightly. It is more common on the hind legs, and is located just above the fetlock. A windgall is a swelling of the tendon sheath, caused by an excess of synovial fluid. There are two types, which I remember from college studies; articular windgalls and non-articular windgalls. The articular windgall being a swelling of the fetlock joint capsule whilst the more common non-articular windgall which is a swelling of the digital tendon sheath.
Windgalls are affected by the environment and climate; a horse who has jumped on hard ground will have more enlarged windgalls the following day, whilst warm days and standing in a box can cause them to swell too. Many people use bandages to support the tendon in exercise, and to reduce swelling when in the stable, but daily bandaging can cause rubs and problems elsewhere in the tendon.
Horses tend to have symmetrical windgalls, and they should be easily compressible with the pea sized pocket of fluid moving around the leg under pressure.
Occasionally windgalls can appear suddenly and cause problems, but this is usually when the tendon fibres are damaged, so called inflammatory tenosynovitis. This can be investigated using an ultrasound scanner and appropriate treatment taken to resolve the root cause. In this case the windgall will be quite hard and tender, and treatment is usually box rest and bandaging along with a course of anti-inflammatories. Some people suggest draining the windgall, but the horse’s body will just produce more fluid to protect the tendon. The best course of treatment for windgalls is to establish the cause: be it tendon damage, or wear and tear, hard ground or warm weather and then support the leg appropriately, using boots or bandages and cold hose the legs if they swell up.