Any horse can get a tendon injury, but our equine athletes are at a greater risk for soft tissue injures due to the additional strains and forces applied during and in preparation for competition. In the past, certain tendon injuries meant the end of a horse’s career or the start of a long and frustrating period of rest; but thanks to the advances in the field of regenerative medicine we are seeing improvement in quality of healing, reduced re-injury rates and less time until return to work. But let’s be honest: It doesn’t make desmitis—inflammation due to an injury to a ligament–any less frustrating because controlled rehabilitation programs are still the most important (and patience-testing) aspect of recovery.
As a budding veterinarian it is important to me to use my time at Hagyard not only to read and be exposed to current research surrounding regenerative therapies like stem cells, Platelet Rich Plasma (PRP), etc., but to pick the brains of experts and hear their opinions formed from years of experience and training. Call me a nerd, but to me that’s the best part of veterinary medicine: We are always learning and changing for the better of our profession.
In Thermal we are lucky enough to have access to the latest and greatest equipment and Dr. Liz Barrett’s expertise to offer and apply regenerative therapies to appropriate cases. Recently we had a horse who presented with a significant left front lameness–what we would grade a 3/5 lameness baseline at the trot. Our examination started with palpation and flexions, and then we began isolating the lameness. Because our patients can’t “point to where it hurts,” we target specific nerves with subcutaneous anesthetic to locally block regions of the limb. Once we had identified the general location of the problem, it was time to image the fetlock with radiographs and ultrasound the suspensory branches and the attachments. The pathology that was discovered at the conclusion of our exam lead to a discussion of therapeutic options to make our new pal sound.
After discussing the available options for this injury, pricing and side effects, one of the therapies chosen was Platelet Rich Plasma. But what exactly is PRP, where does it come from and why is it going to be helpful? PRP is a biological product consisting of concentrated platelets. It is prepared by collecting the patient’s own blood and then processing the sample in a centrifuge-like machine specific for producing PRP. Unlike stem cells, which can take weeks to be cultured, PRP is ready to be injected directly into the lesion in less than an hour. We know that platelets are important in the clotting process, but how do they help tendon fibers heal? The big challenge with tendon injury is that once the fibers have become disrupted the body doesn’t replace them with the same type of connective tissue previous to the injury. This makes the tendon predisposed to future tears and injury because the fibers have less elasticity and strength. Platelets contain growth factors that, when released, aid in the healing process. The theory is that these growth factors produce less scar tissue and a larger percentage of new fibers closer to the strength of the original. With this particular case we injected the PRP into the medial suspensory branch and expect that this will be the only injection needed. However the number of injections varies depending on what is being treated and the horse’s healing response.
That was another glimpse in my life as a HEMI intern and some of the cases I am seeing out here in Thermal, California. Now back to working and melting in the desert!