Description

Periostits of the cannon bone, known as bucked shins is the result of concussive force on the cannon bone of young horses that run on hard surfaces. As the horse's hoofs strike the hard ground or track, the front surface of the cannon bone experiences greater compression than the back surface. This compression causes the periosteum on the front surface to buckle and tear. At the same time, the bone may suffer stress fractures.

The cannon bone responds to this trauma by periosteal remodeling or the depositing of new bone at fracture sites to increase strength and durability.

This high-strain, repetitive motion injury comes from overly rigorous training regimens that don't allow the bone to gradually adapt to the concussive force involved in training, especially on hard track.

As the horse becomes older, the cannon bone becomes more resilient and bucked shins are less likely to occur.

Symptoms

• Swelling over the dorsal region of the cannon bone
• Heat
• Pain
• New bone formation shown in X-rays
• Lameness
• Uneven or choppy gait

Causes

Bucked shins are caused by intense training that places too much stress on the cannon bone. These injuries usually occur during the first six months of training. It is estimated that approximately 12% of horses that develop bucked shins will go on to have stress or saucer fractures, leading to dorsal metacarpal disease.

Prevention

Since bucked shins have been directly related to intense training and racing regimens, prevention is best accomplished by taking the horse's age and condition into consideration and devising a training program that regulates the frequency and intensity of workouts. This way, the bones are strengthened, reducing the likelihood of bone remodeling. .

Several researchers have devised training programs that promote good bone health by decreasing distance galloped, along with conditioning programs to promote bone strength in a systematic way.

Treatment

Once bucked shins develop, treatment is directed at relieving pain and swelling. X-rays should be taken to identify the injury and diagnose the severity, especially if stress fractures are involved. Ice packs, pressure bandages, and Butazolidin may be prescribed by a veterinarian. Cortisone injections will help reduce inflammation. Prolonged rest may be necessary for complete healing to take place.