Shock Wave Therapy and Kissing Spines

Q. I have an 8-year-old mare we show in reined cow horse competition that was evaluated in January and showed early stage kissing spines. My vet said we might be able to do some shock wave before our next show to help this horse. I don’t know much about how shock wave works, and what are the cost and benefits of the therapy for performance horses in helping extend their show careers, especially in the instance of a condition like early stage kissing spines?

A.  Your question is not uncommon and is frequently asked by many trainers and owners to their veterinarians. It is helpful to understand what “kissing spines” are, why the condition is important to consider as a cause of poor performance, and what treatment options are available. Overriding dorsal spinous processes, or kissing spines, occur when the dorsal spinous processes—vertical bone projections of the thoracic or lumbar vertebrae—are abnormally spaced such that they touch or rub against one another. Occasionally, this impingement can cause back pain and secondary poor performance, including inability to bend through the body, poor canter quality, trouble with transitions, bucking, and sour attitude when being tacked up. Often this condition can be diagnosed by radiography and a supportive clinical exam. Ultrasound can be useful to further evaluate adjacent soft tissues, including the ligamentous attachments and muscles that help stabilize these bony projections. If your veterinarian diagnoses kissing spines as a cause of poor performance in your horse, he or she may recommend treatments including systemic non-steroidal anti-inflammatory drugs (NSAIDs), mesotherapy, local injections of corticosteroids, and/or extracorporeal shock wave therapy (ESWT).

Extracorporeal shock wave therapy is used to treat pain and promote healing by delivering high-energy sound waves to injured or damaged tissue. A transducer emits high-energy sound waves, causing a rapid increase in pressure as they travel through the affected tissues, stimulating neovascularization (blood vessel formation), production of growth factors, osteogenesis (bone production), analgesia (pain relief), and other anti-inflammatory cellular processes. Often a series of treatments is prescribed. Most commonly an initial treatment dose is applied once every two weeks for three treatments and then as needed to control clinical signs.

While shock wave therapy can be financially limiting, it is noninvasive, has few negative side effects, and has proven to be quite effective in the treatment of kissing spines. In general, clinically significant kissing spine issues typically need a multifactorial treatment approach for resolution of signs, but shock wave therapy is a cornerstone to the approach. Regular, intermittent shock wave in the early stages of kissing spines can provide enough comfort between treatment sessions that the horse may begin to appropriately use his body, rounding his back more comfortably, helping to develop topline musculature that adds support to the vertebral column. In addition to the direct effects of shock wave, these secondary improvements can also help slow the progression of the disease process, potentially lengthening his athletic career.