SIJ is the abbreviation for sacroiliac joint. The first problem with the sacroiliac joint is that it is out of reach of both manipulation as well as imaging. “The SIJ is particularly inaccessible due to its depth within the pelvis and the surrounding musculature, making it impossible to palpate the joint externally.” (L. M. Goff, 2008). The second problem is that the sacroiliac joint is subject to very minuscule range of motion. For instance, measurements effectuated on the sagittal plane have found that the range of motion of the SIJ was less than 1°. In fact all the SI damages observed on horses affected with sacroiliac dysfunction are all due to excessive movement and therefore instability of the joint. Stability is the main issue and consequently, all therapies attempting to release muscles, tendons and fascia involved in the stability of the sacroiliac joint are likely to create sacroiliac dysfunction instead of treating the problem. The third problem is that palpations are extremely problematic. The SI joint itself is out of reach and the only palpation that can be made is on the dorsal sacroiliac ligament (DSIL), which is greatly involved in the stability of the SIJ. However, if it might be possible to access the DSIL on a skinny horse, the mass of the gluteal muscles renders any manipulation quite difficult on a horse properly muscled up.
There is a battery of tests and manipulations that have been proposed for horses based on manipulations applied to humans. However, while a human is likely to participate in the manipulation knowing that some pain during manipulation might lead to better reeducation in the future, the horse, which lives in the moment, is more likely to protect himself from any stimulation of pain, resisting the movement that the therapy is suggesting. Therefore, even if some movement might have some therapeutic effect, their application through manual manipulation is unlikely to occur. Instead, therapeutic movements can be created riding the horse or working the horse in hand through the technique proper to the science of motion.
The most important concept relative to SI injury is that the main problem is about lack of stability. Instability is either caused by incorrect work of the muscles and tendons and ligaments associated with the joint or due to pathologic changes within the joint. In fact, pathologic changes are the more advanced level of a problem that started with poor or inappropriate muscular work. The therapy is therefore about recreating stability of the whole system. This is the topic of our Sacroiliac Day which is Friday February 17th, 2012 starting at 10am.
SI Day, Cleaning up the misconceptions.
There are numerous misconceptions and even misinformation about Sacroiliac Dysfunction. A very common misconception is the belief that one tuber sacrale higher than the other is an indication of SIJ subluxation. The tuber sacrales are the two small protuberances which are visible on the top of the croup. Each tuber sacrale is the head of the wing of ilium, which are the wings of the pelvis. It is true that acute sacroiliac strain can lead to pelvis deformation lifting one tuber sacral higher, but such acute case also causes severe lameness. Instead, it is not uncommon that one tuber sacrale is higher than the other simply because the wings of the ilium do not grow in perfect symmetry. Another case leading to the same visual impression is transversal rotation of the thoracolumbar spine which places the sacrum and the pelvis in a slight transversal inclination. If not corrected by appropriated gymnastic the transversal rotation can became chronic as back muscles and also ligaments adapt to the torsion. The pelvis cannot be replaced manually. Instead, a gymnastic program focusing on recreating muscle imbalance between right and left side of the thoracolumbar column is the therapy. In fact, transversal rotations of the horse’s thoracolumbar spine are mostly located between the 9th and 14th thoracic vertebrae, which are basically between the rider’s thighs, therefore, corrective gymnastic needs to focus on this area of the horse’s vertebral column.
One needs to realize that it is not the sacrum which support the pelvis but instead the pelvis that support the sacrum. The pelvis is supported by two columns which are the hind legs. The sacrum is suspended under the pelvis and is very tightly attached by a system of ligaments. This is why the sacroiliac joint is not built as a joint supporting compressive force but instead as a joint designed for sliding motion. However, very little motion occurs between the sacrum and the pelvis. The SI day will start with a clear description of the sacroiliac joint, offering to the participants the unique opportunity to manipulate a pelvis and a sacrum and fully comprehend how they are attached and function. JLC
Jean Luc Cornille 2012