Extracorporeal shockwave therapy is a widely used treatment for painful orthopaedic conditions in horses, dogs and humans. In humans it has been used for the treatment of gallstones, uroliths and burns. There are also recent, promising reports of its use as a novel treatment for burns in horses.
Extracorporeal shockwaves are pressure waves that are generated outside the body which can travel through fluid and soft tissue. In equine practice, the main indications for use of shockwave therapy are for the treatment of insertional desmopathies and the stimulation of osteogenesis. Insertional desmopathies? Osteogenesis? Okay, lets explain.
A desmopathy is a disease of the ligaments. When we refer to an insertional desmopathy, we are referring to an orthopaedic condition of the bone-ligament or bone-tendon interface. In humans, the types of conditions that are successfully treated with shockwave therapy include epicondylitis humeri radialis (tennis elbow), epicondylitis humeri ulnaris (golfers elbow) and plantar fasciitis (heel spurs). Shockwave therapy enhances the healing rate of the bone-tendon interface resulting in higher tensile strength. This means that if damaged tendon fibres are treated with shockwave therapy during the healing process, they will be stronger as a result.
Osteogenesis is the formation and development of bony tissue. The cells that lay down new bone are called osteoblasts. A number of in-vitro studies have demonstrated stimulation of osteoblasts after application of shockwave therapy and a resultant increase in osteogenesis.
So, how do we apply this information to equine practice?
A great example, is the use of shockwave therapy to treat proximal suspensory desmitis. This is pain originating from the origin of the suspensory ligament. We diagnose this condition in both the forelimbs and hindlimbs and we most commonly see it in mature sport horses and young racehorses.
We begin the process of reaching a diagnosis of proximal suspensory desmitis by localising pain to the area using a combination of palpation and nerve blocks. To confirm our diagnosis we use a combination of radiographs and ultrasound. In some situations, nuclear scintigraphy can also be useful to confirm a diagnosis.
Our treatment recommendations for this condition vary based upon the degree of lameness, the severity and exact location of the lesion, the use of the horse and the budget of the client. Our management plan may include one or more of the following; controlled exercise, intra-lesional injection of cortisone or platelet rich plasma, surgery, rest and shockwave therapy.
When we recommend shockwave therapy, the basic course of treatment consists of three treatments two weeks apart, however in some situations we may alter the treatment depending on the severity of the injury. The horse requires sedation and each treatment is directed at the origin of the suspensory ligament.
The analgesic effect of shockwave therapy is well accepted. So, in addition to the beneficial effects that shockwave therapy has on tendon fibre recovery and osteogenesis, we also see a rapid reduction in degree of lameness. This reduction in lameness, combined with the other aforementioned benefits of shockwave therapy, makes shockwave therapy a great addition to the arsenal of treatments we can use to manage proximal suspensory desmitis in our equine patients.