Diagnosis and Treatment

By Dr. Billy Hodge

In recent years the addition of the back examination to a routine lameness exam has become commonplace. With vast amounts of information available on the internet and social media pages, it can be daunting to understand and clarify “back pain” in the sport horse. This article will organize the clutter of information into a clear picture for riders and owners.

Most Common Causes of Back Pain

Anatomically, the mid/caudal back of a horse is comprised of bone (eighteen thoracic vertebrae, six lumbar vertebrae, and the sacroiliac articulation to the pelvis), linked by soft tissues (ligaments), which together form joints that are propelled into action by muscles.

Summarized below are the most common causes of back pain in the sport horse, depending on the horse’s discipline. 

This image shows the most important structures of the horse’s anatomy relative to the regions of common injuries in the horse’s back. Any of these areas can become injured. Photo: Thinkstockphotos/GlobalP & Canstockphoto/Andriioliinyk

Muscle and Soft Tissue Pain From Incorrect Saddle Fit

Horses can become locally or generally sore from an ill-fitting saddle. Horses, like humans, can change shape as they grow and develop more muscle, even during the show season. Just as we need to adjust our gear as riders, the horse must have tack that fits correctly in order to succeed.

The horse’s back changes over time due to training, nutrition, and other factors. For this reason, the fit of the saddle should be checked at regular intervals and adjusted to accommodate these changes. Photo: Dreamstime/Chernetskaya

Related: Equine Sports Medicine

Diagnosis & Therapy: Ill-fitting tack can lead to pain that can present acutely or as a low grade, longstanding issue. This will usually present as the horse being unhappy with saddling, areas of rubbing, white hairs, hair loss, saddle slipping, and/or areas of bruising-tenderness-swelling, which can be felt. Clinical examination is usually sufficient for diagnosis, but incorporating radiographs and ultrasound can aid in ruling out other common issues.

Laser therapy is the use of an intense beam of laser light directed into the patient’s tissue. This reduces pain, inflammation and accelerates healing. The laser causes vasodilation, which brings healthy nutrient-rich blood to the target area. It also brings more oxygen to the cells and generates more energy. Increased energy for the cells means quicker recovery, enabling wounds and other injuries to heal faster and with better quality fibre alignment.

Laser therapy has a multitude of uses for both acute and chronic injuries as well as for pre-performance use. At this time only FEI classes have a withdrawal time assigned to laser treatments. Photo courtesy of Meadow Lane Equine Clinic

Usual therapy is one to three weeks of back free exercise, topical or oral nonsteroidal anti-inflammatory drugs (NSAIDs), and careful saddle fitting. In our clinic, we routinely use laser therapy and/or light therapy with acupuncture to help relieve some of the tension that has developed.  

Extracorporeal shockwave therapy is widely used for managing pain and optimizing healing in soft tissue injuries. Its most common application is following tendinous or ligamentous injury and for management of navicular syndrome. It can also be helpful in treating back and neck conditions, and select cases of bony injury. Photo courtesy of Meadow Lane Equine Clinic

Overriding Dorsal Spinous Processes or “Kissing spine”

The pain arises from the region known as the dorsal spinous processes. This condition can be found in all disciplines and breeds of horses, and in horses of almost any age. 

Equine back showing kissing spine. X-rays confirmed that eleven of this horse’s vertebrae suffered from kissing spine, and four vertebrae had fused together.

Diagnosis & Treatment: This condition can be suspected in horses with pain on palpation, saddling, walking, trotting, and commonly in the canter. It can be diagnosed and graded by the lesion seen with radiographs, ultrasound, or gamma scintigraphy (bone scan) and by the presentation clinically (mild, moderate, severe). Interestingly, the radiographic findings often don’t support the clinical findings. This individual variation is seen often and can be confusing for owners. Some horses may have severe signs with only one area of abnormality on radiographs, and other horses will have moderate to severe radiographic findings with mild clinical signs.  

Related: Equine Rehab for the Not-Quite-Right Horse

Often there is a bone component, as well as soft tissue and local nerve-associated pain, making treatment of “kissing spine” case dependent. Therefore, a single therapy is usually unable to significantly reduce pain and improve rideability. Treatment should be aimed at reducing pain, and this will usually involve local ultrasound-guided injections, bisphosphonates, a short course of NSAIDs, mesotherapy, shockwave therapy, and regenerative laser therapy (RLT). Therapies such as the Bemer Blanket and Magna Wave have not been clinically trialled and therefore the exact response is not discussed here. There are anecdotal reports of improvement with their use. 

Supraspinous Ligament Injury

Photo: Thinkstockphotos/GlobalP & Canstockphoto/Andriioliinyk

This is a relatively common injury found in sport horses. The supraspinous ligament is very elastic and can be over- stretched resulting in mild to moderate tearing causing pain and reduced performance. It is usually a sudden onset swelling over the midline back region, and diagnosis is strongly supported by palpation.

Diagnosis & Therapy: Ultrasound is the diagnostic technique of choice, and examination with careful evaluation of this fibrous/ligamentous structure that runs from the top of each dorsal spinous process and has a wave-like undulation along the back.

The horse should be rested for up to four to six weeks, with non-riding exercise allowed. Topical and oral NSAID treatment should be given until signs of pain and inflammation have subsided. The injury can be also treated concurrently with shockwave and RLT in addition to local therapy depending on the acute/chronic nature (ice/heat). 

Related: Understanding Equine Back Pain

A unique non-surgical technique that allows horses to work and compete with less pain, mesotherapy uses a mixture of homeopathic substances which are injected along a region of pain (usually the back, sacroiliac, lumbosacral areas). The injections are made in the skin layer called the mesoderm where nerve fibres that provide deep pain sensation are “dampened” in order to allow pain-free movement. This very effective method of pain relief is commonly used to treat conditions such as sacroiliac joint disease, lumbosacral joint disease, kissing spine, facet joint disease, and fractured withers or degenerative joint disease. Photo courtesy of Meadow Lane Equine Clinic

Thoracolumbar Facet Joint Pain (Osteoarthritis)

Osteoarthritis is a relatively common finding in sport horses but rarely discussed or diagnosed. It can present as acute or chronic pain arising from the thoracic/lumbar facet joints (the small interlocking joints that allow rotation in the back). Loss of performance, decreased rideability, and behavioural issues when ridden are all possible manifestations.

Diagnosis & Treatment: This condition is diagnosed by ultrasonographic evaluation of the joint just off midline. 

The use of scintigraphy can be warranted but is expensive and requires special equipment. Radiography is also utilized but precise technique is required as well as a machine with higher settings (KV/Mas).  

Related: Equine Chiropractic

Sacroiliac Pain/Dysfunction

This very common condition affects horses of all ages, breeds, and disciplines. The presentation is acute pain, or more commonly chronic pain, resulting in poor performance, decreased ability to canter, swapping leads, behavioural changes, inability to hold one limb up for long periods of time (difficulty with farrier), and in some cases sore on palpation over the sacroiliac region. 

Diagnosis & Therapy: An experienced ultrasonographer using careful rectal ultrasound or scintigraphy can diagnose this condition. A misconception that a “hunter’s bump is suggestive” of sacroiliac pain is untrue.

Therapy is directed at decreasing the pain in the sacroiliac region, and therefore cases should be treated utilizing a short course of oral NSAIDs, sacroiliac injections using steroids (ultrasound guided), platelet-rich plasma therapy such as Pro-Stride or IRAP. Horses should have reduced work for two to three weeks depending on presentation. Rehabilitation using a walker or high speed setting is ideal for up to 45 minutes a day. The use of mesotherapy (multiple mesoderm injections) can be utilized along with RLT, shockwave, and acupuncture. Moderately affected cases will need longer rehabilitation and may have concurrent other lameness issues which should be identified. 

Acupuncture is typically performed without sedation and begins with a thorough history and musculoskeletal examination of the horse. Saddle assessment or soundness evaluations may also be performed. Acupuncture can be very beneficial in the diagnosis and relief of musculoskeletal pain caused by ill-fitting tack, trauma or extended lay-up, kissing spine or other conformational abnormalities, laminitis, muscle atrophy secondary to nerve injury, and compensatory musculoskeletal pain secondary to lameness. Photo courtesy of Meadow Lane Equine Clinic

The list of conditions is not exhaustive but would be considered our most common case load. The equine back is now a common part of all lameness exams and a careful examination with a thorough history, coupled with a ridden exam if possible, is key to diagnosing primary back pain in horses. 

We commonly see both primary and secondary back pain in horses. The widespread use of radiography and ultrasound has made diagnosing back pain much more reliable. Therapy is never a single approach, but usually a selection of beneficial therapies (mesotherapy, local/systemic injections, shockwave, and saddle fitting) are chosen. With patience and correct diagnosis, equine back pain can be managed in the majority of cases.

Related: Osteoarthritis - Keeping Our Aging Horses Sound

Related: Spinal Problems in Horses

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Main Photo: Shutterstock/Catwalk Photos