The Dangers of Leg Yielding
Michael Baxter is a Canadian and is the founder of the International Academy of Sports Therapy. In 1998 he presented a research paper at the Association of Sport Medicine in USA. The research paper was called "Swinging Hip Syndrome". The focus was on:- 'Hindend irregularities are inclined to cause forelimb lameness'. It has been proven that many forehand lameness and back problems result from improper hindend movement patterns. It is well documented that rotational stress and concussion forces on the joints, as well as trauma, age, confirmation, muscle fatigue and muscle misuse are possible causes of osteo-arthritis.
WHAT IS SWINGING HIP SYNDROME?
This is a biomechanical stress. The hypothesis is based on the fact that 80% of the horses that were filmed in a 12 metre circle on the lunge and also with a rider, have one asymmetrical side. They showed excessive lateralization of the inner hind leg. The inside hind does not track straight into the front feet tracks as it should, but moves across the mid line of the body and crosses the outside hind leg. This is the same as leg yielding. It is best seen on the video in slow frame on a circle.
WHAT CAUSES SWINGING HIP SYNDROME?
- There are many causes, but the majority are rider faults: A major cause of swinging hip is leg yielding. For most people, leg yielding is incorporated into the horses work and is in dressage tests. Swinging Hip Syndrome is one of the main reasons for lack of forwardness. This happens when the rider tends to use excessive inside leg to push the horse into the outside rein. This causes further deviation of the inner hind leg and compression of the vertebrae.
" Too many circles causes rotational stress through the body.
" Improper lunging techniques and regular lunging.
" Rider pulling on the inside rein.
" Too much neck bend on circles.
" On a circle horse falling onto outside shoulder
" Rider sitting crooked.
BIOMECHANICAL STRESSES PLACED ON THE BODY
A horse with swinging hip syndrome will drop the inside hip on the circle causing the hind feet to land on an angle to the ground. The shoulder will fall outwards and the inside shoulder will be over loaded. This places strain on the knees, suspensory ligament, hocks, stifles, sacro-iliac joint and other joints of the body.
Due to rotational stress of the lumbar vertabrae, behind the saddle, the muscles in the hindquarters, back and ribs go into a protective spasm to try and keep the vertebrae more stable. This will effect the lumbar-sacral joint. This joint and muscles around it are responsible for propelling the horse forward, lengthening and shortening of the stride and the ability for the horse to move well.
The forehand will also suffer. There will be a slight hollowing of the back. This causes the spines of the vertebrae to get close together and touch. This is why this condition is called Kissing Spine Syndrome. This leads to vertebrae blockage at the base of the withers (T9-T12). When there is rotational stress here, this leads to referred pain in C5,6,7 vertebrae at the base of the neck in the brachiocephalic muscle. This muscle creates movement of the head and forelimb. Muscle tension at C7 will pinch on the brachial nerve supply that regulates blood flow in the front limbs. If the blood supply is reduced, the horse will be more inclined to develop joint and tendon injuries and move with short choppy strides.
Swinging hip syndrome is very destructive to your horses health because it creates instability within the joints and blockages of others. In a vast majority of cases, prolonged instability gives rise to the premature degenerative changes in joints, intervertebral disks, ligaments, tendons, and muscles. Posture imbalances is one of the leading causes of strain and pain in the horse.
Every athletic horse suffers some degree of joint damage during it's career, simply because the forces on the joint surfaces far exceed the joint repair properties. Although some horses never demonstrate any signs of these joint changes, many do. Joint degeneration is silent and slow. In the early stages of joint injury, it goes unnoticed. When clinical signs do appear, we usually search for a "magic" cure or medication to treat the joint, ignoring the long term consequences. Prevention of injuries is better than cure.
Laser therapy, acupuncture, massage and physical therapy give relief but can never restructure the muscular imbalances. They will increase blood supply, relieve pain or reduce healing time. It is important to remove the cause of the problem and not just treat the symptoms. Only then with a well structured muscle training programme and therapy treatment plan, will successful changes be made. The therapist and rider must work together.