Approach to Diagnosis and Therapy of Back Pain

Introduction

While one of the most common complaints related to athletic performance of the sport horse, the diagnosis of back pain can be complex. The signs are easy enough to recognize, however the underlying cause may be perplexing. The rider or trainer may perceive that a horse has back pain from a number of clinical signs. These may include sensitivity to grooming and saddling, resistance to rider weight, stiffness, pain on manual palpation of the back, and poor jumping performance. Many of these symptoms may arise as secondary issues to other lameness problems, particularly of the hind limb, and the difficult issue is determining the origin of the problem. Back pain may be due to secondary muscle strain related to hind limb lameness producing an altered gait, primary muscle strain related to athletic effort or a fall, impingement of dorsal spinous processes, strain of the sacroiliac ligament, poor saddle fit, inflammation of the supraspinous ligament, trauma to spinous processes, and facet joint arthritis to name a few. A thorough physical examination, coupled with a complete therapeutic approach can most frequently relieve symptoms of back pain.

Physical examination

The examiner should first attempt to rule out lower limb problems as a cause for the development of back pain. Hind limb lameness such as distal tarsitis, chronic proximal suspensory desmitis, and gonitis may contribute to significant muscle soreness in the low back because of an altered leg swing related to a resistance to flex the lower limb or bear weight. Chronic forelimb soreness, particularly foot soreness, may contribute to back pain in the jumper because of an inverted way of going that attempts to protect the forelimbs on landing after a jump. Something as simple as an ill-fitting saddle can be the source of significant pain and should be considered. Bad teeth that cause mouth pain and an inverted way of going may lead to back pain. The horse’s neck should be carefully evaluated for painful responses as well. The examiner needs to develop confidence in his or her palpation technique and trust the observations made. It may take considerable time to develop a cautious and smooth palpation technique that elicits true pain responses but doesn’t startle the horse. A complete physical examination should include palpation, passive and active flexion tests, jogging, lunging and riding the horse, and imaging as indicated by the physical examination. Radiography and ultrasound are very valuable tools in the evaluation of back pain. Modern digital radiography makes diagnostic radiographs of the back possible with portable x-ray machines and ultrasound examination may reveal joint and soft tissue abnormalities of the neck and back. [...]