PRP for Stable Stress Fractures

A stable stress fracture is one in which no shift has occurred in the bone alignment. This differs from another common type of stress fracture, a displaced stress fracture, which is an injury characterized by the ends of the bones becoming unaligned.  When a horse develops a stress fracture, the prognosis is generally good, that is if the fracture is a mild one (stress fractures are considered fairly mild). If proper care is rendered, a horse should recover and have full use of the injured body part.

It is important to note that equine fractures tend to heal slower than those experienced by human beings. Severe fractures can be disastrous at least they were in the past. Not too many years ago, a horse that developed a severe fracture, would either be forced into retirement or euthanized. Today, veterinarians are better able to treat fractures so that such injuries aren’t necessarily considered career ending or life threatening, though they still can be.

Stress fractures are pretty common, especially amongst performance and racehorses. This is because these types of fractures are typically caused by overuse. Because the aforementioned types of horses are very active and are typically trained quite hard, the likelihood that they develop a stress fracture is higher than horses which are not.

A stress fracture may also be referred to as a green stick or incomplete fracture. When a horse suffers from this type of injury the bone has split or crack. It doesn’t actually break off, in two or into pieces. A stress fracture occurs due to continual stress. Prolonged stress causes the bone to split or crack. Again, these types of fractures are not unheard of amongst racehorses or performance horses. In fact, they are fairly common. These differ from fractures which occur suddenly, as a result of sudden trauma..

In order to treat a stress fracture, it is first necessary to diagnose it. There are a number of ways in which a veterinarian will do so. Because these types of injuries are so common, the diagnostic procedures used to determine whether or not a horse is suffering from a stress fracture, are pretty cut and dry.  The vet will first consider the symptoms they either observe or are reported to them by the horse’s owner or trainer and then will perform some type of scan.

It is extremely important that a stress fracture be diagnosed as early as possible because if it is not, and isn’t subsequently treated, the stress fracture can develop into something much more serious. The fortunate thing is, if horses receive proper treatment after developing a stress fracture, they can make a full recovery and will be able to once again, compete in whatever arena they did prior to developing the injury.


Equine stress fractures develop over time. They never occur suddenly or as the result of a traumatic event. Instead, as the name suggests, stress fractures are the result of ongoing stress being placed on the bone. The reason that stress fractures are fairly common amongst performance and racehorses is because they repeat the same activities over and over. These activities typically place a great deal of stress on the limbs and as a result, stress fractures develop. While performance and racehorses are most susceptible to equine stress fractures, they can occur in other types of horses.

It is important to note that stress fractures can develop into more serious fractures if they aren’t diagnosed and treated. It is thus very important that owners recognize their horse’s susceptible to these types of fractures and take necessary precautions and vigilantly be on the lookout for possible injuries. Once a problem is suspected, a diagnosis should be sought by a veterinarian.


When a horse develops a stress fracture, it may or may not exhibit extremely noticeable symptoms. Often times, a diagnosis will be the result of a vet eliminating other possible ailments before being able to definitively diagnose the injury as a stress fracture. Because stress fractures are splits or cracks in the bones, the injury may not be as obvious or easy to diagnose as a complete fracture or break would be. Therefore, a little detective work may be required.

Horses with stress fractures may exhibit some mild lameness. Lameness is characterized as a change in gait caused by pain or some other physical restrictions. A horse with a stress fracture may change its gait because it is in pain. Once an owner recognizes this, it is important that he or she call a vet because the sooner the injury is diagnosed and treated, the better. The more time that passes, the worse the condition will become. If too much time lapses, a much more serious injury can develop and a performance or racehorse may be out of commission for longer than it would have if the stress fracture was diagnosed and treated early.

The location of the stress fracture and how severe it is will determine the amount of lameness a horse exhibits. For example, a hose that has a stress fracture in its tibia may exhibit a significant change in its gait, though not for very long. After a week or so, the horse will probably begin to walk normally. Because a horse gait may suddenly improve the likelihood that the stress fracture may not be diagnosed right away is very real and not at all uncommon. An owner may mistakenly believe that that horse of fine, when it fact, it isn’t.


A stress fracture, while not difficult to diagnose, requires more than palpitation and an x-ray. Because stress fractures are less severe and the symptoms not as noticeable as those caused by a complete or at least very bad fracture, it requires a bit more investigation to diagnose it. For instance, because stress fractures can’t always be diagnosed via x-ray, it is sometimes necessary to use other diagnostic tools, for instance, nuclear scintigraphy.

Nuclear scintigraphy, also known as bone scanning, is a procedure that utilizes an IV injection of radioactive materials. Nuclear scanners are used to detect the radioactive material and present stress or hidden fractures.  X-rays may be taken but can be unreliable because stress fractures don’t always show up in x-rays.


A stable stress fracture can be treated with PRP (Platelet Rich Plasma) therapy, along with stable rest and possibly a splint. If the fracture is caught early enough, it may not be necessary to splint the injury. PRP therapy would be used to speed up the healing process and would be used in the conjunction with the aforementioned. A horse that is treated with PRP may be able to return to form significantly sooner than a horse that is not. This is because of the treatments use of blood platelets and the growth factors they contain. Growth factors are utilized by the body to heal injured tissue and bone. When concentrated amounts of growth factors are injected into the body (which they are during PRP therapy), the healing processes is significantly sped up. Healing takes place much faster.

PRP treatment is a natural treatment. It utilizes the horse’s own growth factors to heal itself. The procedure is non-invasive and there are few, if any, complications. Side effects are rare and minimal.  The most serious potential complication is an infection developing at the injection site. This is the same potential infection that a horse might develop anytime it received a shot or injection. Complications don’t typically occur because, again, a horse’s own platelets are used in the procedure. Very little foreign substances are.

A PRP procedure is quite simple, though a vet has a few options when it comes to administering it. Autologous blood PRP is the most conventional form of the procedure. The use of PRP gels and sprays are newer but catching on.

 To begin PRP treatment, a vet will draw about 52 mLs of blood from the horse into a 60mLs syringe with an anticoagulant solution. 52 mLs of blood is commonly used, but varying amounts may be.  Prior to drawing the blood, the horse will be sedated and given a nerve block.

After the correct amount of blood has been drawn, it will be placed, while still in the vial, in a centrifuge machine. The centrifuge machine will spin it. The purpose of doing so is to separate the blood’s components. Blood is made up of red blood cells, white blood cells, plasma and platelets. Once separated, the platelets are removed and injected into the horse. The area is bandaged and the horse will be required to rest. Post-procedure care will not only be dictated by normal PRP protocol but also those guidelines which govern the treatment of fractures.

A vet may or may not use autologous blood PRP therapy as explained above. He or she may use a PRP gel or spray. More than one application of PRP may be needed. The pace in which and how well the injury heals is likely to be the primary, determining factor. Ultrasound guidance is not normally required.