Leg swelling in the horse is a common finding, especially in the equine athlete. The most common problem associated with swollen legs is poor circulation, which can be attributed to many underlying problems. In most cases, we refer to this problem as ‘stocking up”, which is most often seen in the mornings after a horse has been stalled at nite. Usually, this stocking up resolves with increased movement, which signifies circulatory problems, but in other cases, it can be more stubborn, persisting for longer periods of time. Equine cellulitis is one of those conditions that tends to persist and create marked frustration.
Stocking up in the horse is really a condition in which fluid accumulates in between tissue layers in the leg. It can be a result of poor circulation, in which blood tends to pool in the leg due to poor return to the heart, which can signify cardiac, blood pressure or even liver concerns. In the legs, and other parts of the body, the veins return blood and fluid to the heart, but there is a backup mechanism called the lymphatics, which is a small network of tubules that essentially drain excess fluid that may not be present in the blood stream. The lymphatics gather up this excess fluid and through the network, move it back to the heart, where it can rejoin the overall circulation. When fluid does accumulate, swelling results, and this can signify that there is a problem with return of fluid back to the heart and general circulation. In most cases, the swelling occurs after a period of rest or stall confinement. The reason for this is that movement is reduced and movement is necessary in the horse to encourage blood and fluid return out of the limbs. The average horse does not stock up with stall rest, so when this does occur, it should be a sign that a problem may be present.
Celluitus is an inflammatory process that may be present with infection, usually involving the soft tissue structure of a certain region. Lymphangitis is technically inflammation of the lymphatic network, which may accompany an infection or wound. Both conditions can lead to a swollen leg and stocking up presentation.
The exact causes of stocking up are many including infection, trauma, cardiac concerns and even liver problems. Fluid has a natural tendency to stay within the blood vessels due to oncotic pressure. When oncotic pressures drop, for what ever reason, fluid can leak out and will accumulate in dependent regions. One protein, Albumin, that is produced by the liver helps to maintain oncotic pressure and when albumin levels are low, fluid can leak out. In these cases, not only are the legs usually swollen but there is also fluid accumulation on the midline of the abdomen.
The diagnosis of cellulitus and/or lymphangitis is not complicated. In most cases, the leg is swollen and has what is termed ‘pitting edema’, which is tight swelling which will leave a finger impression upon deep palpation, almost like pushing your finger into bread dough. Most of theses horses are weight bearing and will walk on the affected limb, but may become increasingly lame if the problem progresses. Bloodwork is often done to rule out other problems such as infection and organ damage. Ultrasound examination and x-rays may be warranted, especially if there is trauma or a wound, making sure there are no fractures or joint involvement.
The treatment for the condition can be just as variable as the cause, and is really cause dependent. In most cases, bloodwork is usually done to rule out problems such as infection, kidney and liver disease, and to check various protein values. Most standard therapies employed, regardless of cause are cold or warm water hosing of the limb to improve circulation, snug wraps of the legs to force fluid back into the circulation, topical sweats to pull out excess fluid and of course movement. I am nore one that is in favor of light turnout or even forced work, which is dictated by the horse and level of lameness. I feel that continual stall rest in these cases can do more harm than good.
If infection is present with a wound or even foreign material, then surgery may be warranted to open, drain and debride the region. With infection, we usually will run a course of antibiotics and even perform regional limb perfusions, which helps us to get higher antiibotic levels to that specific region.
Prognosis for Recovery:
The prognosis for most cases of stocking up in the horse is usually pretty good and favorable. The exact prognosis is dependent on the exact cause, how much damage is present and how long the condition has been present. Time is critical in these cases, as with more time that passes, more swelling occurs which can not only impede circulation further but the ongoing inflammation can contribute to scar tissue, which may impact range of motion and future soundness. In cases of lymphangitis, in some cases, the ongoing infection and inflammation may scar these structures, thus impacting future fluid movement in and out of the leg. Those horses are often then prone to stocking up more readily in the future.
“Microbabe” is a 9 y.o OTTB mare that was rescued by Central Virginia Horse Rescue. She has sustained an injury of unknown origin and was found in the killer sale, tucked away in a corner with a swollen leg. The left rear limb was diffusely swollen, extending up into her left stifle at times and she was very hesitant to bear weight and use the leg. There was an evident healed over wound on the outside of the left rear fetlock, but exact cause was unknown.
She received the highest level of attention by her caregivers, including referral to a veterinary teaching hospital where surgery was done to help drain fluid from the leg and regional limb perfusions were performed to aid in infection control. “Microbabe” was placed on systemic antibiotics and anti-inflammatory medications, which she has remained on essentially for the past year since her acquisition. Over the course of therapy, the left rear leg would improve at times with swelling reduction and lameness improvement, but on other days, it was completely swollen again with her being reluctant to bear weight.
“Microbabe” was presented to our rehab facility in mid April of 2015. At the time of presentation, she was grade 5/5 lame and very unwilling to put weight on the left rear, but would toe touch to ambulate forward. She had been on an extended course of antibiotics including doxycycline and enrofloxacin, with no improvement noted by the rescue group.
The focus of our attention in her therapy was to manage the inflammatory response that was present and impeding circulation of fluid from the leg. In all likeliness, there was a tremendous amount of scar tissue present due to the prior injury and even as a result of ongoing infection, which may impair the full recovery to an extent. At this point, x-rays were performed of the fetlock and hock, with no visable problems evident on a boney level, but scar tissue or calcification was noted around the hock region. The ongoing swelling and scar tissue was impeding her movement and ability to fully bear weight, essentially restricting her and creating pain.
When we look at the inflammatory process, we realize that it is a complicated one. Many anti-inflammatory medications can be beneficial but are somewhat restricted in their scope of managing inflammation, often just addressing one or two aspects of the process. The other question in this case is ‘where does the inflammation come from?”. Why does she float back and forth between no swelling and full swelling?
In many cases of equine lameness and health concerns, the gastrointestinal tract and health in this region can give us some clues as to the process. In many respects, and based on research findings, often there is a shift in bacterial balance within the hindgut which occur secondary to stress, diet and many medications. Continued use of antibiotics and even anti-inflammatory medications can have negative impacts on gut health not only from an ulcer standpoint, but can also directly impact bacterial levels. Stress, which often accompanies any health condition, can also impact bacterial levels due to increased levels of cortisol.
In the case of “Microbabe”, is was theorized that she had ongoing hindgut concerns, possibly with translocation or movement of bacteria from the intestinal tract to the general circulation, which may continually ‘seed’ the region, but also ignite inflammation on a persistent level. Based on our prior research project, we submitted feces from ‘Microbabe’ for culture and analysis. Her results indicated that she had a significant overgrowth of lactic acid bacteria (Lactobacillus species), while she also had a significant reduction in overall bacterial levels. So, in reality, the persistent use of antibiotics had reduced her overall gut bacterial levels and other factors led to the heightened levels of lactic acid producers. This shift can potentially correlate not only with decreased digestion and nutrient absorption, but can also contribute to ongoing inflammation and immune problems.
“Microbabe” was placed on the Cur-OST® EQ Total Support formula, twice daily, with the goal of managing the ongoing inflamamtory response and addressing the process of healing any gastrointestinal damage that may be present and potentially contributing to leaky gut problems. She was also placed on the Cur-OST® EQ Immune formula once daily to encourage a proper immune response and provide amino acids to aid in restoring circulation and tissue repair. A topical sweat consisting of DMSO, Dexamethasone and Curcumin was applied once daily in the evening with a breathable wrap applied. She was stalled at night, but turned out by day. She was also placed on a short course of SMZ/TMP antibiotics to help clear up any residual bacteria that may be present. The goal was to get her off the antibiotics as soon as possible, while allowing our other therapies to take hold. We wanted to minimize further damage to the gastrointestinal tract.
She had a tremendous amount of inflammation that was contributing to the ongoing swelling in the leg and associated discomfort, but this inflammation was not being managed with traditional approaches. Through the use of herbs and Cur-OST®® formulas, we tackle the inflamamtion on a higher level, more completely and without side effects. We also wanted to target the gut, which was perceived as being a major culprit in her situation, reducing inflammation in this region, improving health, which will result in less bacterial translocation, more microbial balance and improved nutrient absorption, which improves healing rate.
Within 48 hours, “Microbabe” was almost completely weight bearing on the left rear. On turnout, she was walk fairly well, but would want to trot, doing so using only three legs, which is what she had become accustomed to doing in the past. Over time, her weight bearing improved and we began to do light lunging after 1.5 weeks, helping to encourage improvement in range of motion to the left rear, freeing up scar tissue. Range of motion exercises were also employed to improve movement. She wanted to use the leg, but just didn’t seem to trust it.
After 2 weeks, the swelling had resolved by about 40% with improved range of motion. She was almost completely sound at the walk and on the lunge, she was now using the left rear leg with each stride, but still had an obvious hitch in her gait.
Here are some photos after two weeks:
The long term prognosis for “Microbabe” is good for pasture turnout and soundness. We do not know how much the swelling will further reduce, as the injury is old and scar tissue dominant. I believe and am hopeful that with continued management and support, along with movement, she will lead a comfortable life. In this case, we discover just how important the GI tract and health in that region can play in other areas of the body.
Tom Schell, D.V.M.