I haven’t forgotten my Osteopathic terminology – the only time I will use the term thoracic in place of dorsal is in the title of my posts! It is now time to continue up the column to the eleventh dorsal segment.
The eleventh dorsal segment is part of the thoraco-lumbar junction with the twelfth dorsal segment and the first lumbar segment. As such the eleventh dorsal segment shares characteristics with a lumbar vertebra (such as a more posteriorly directed spinous process, a larger vertebral body, smaller transverse processes). The eleventh rib articulates directly with the body of the eleventh dorsal segment thus providing a greater degree of movement when compared to the dorsal segments above it.
The visceral structures that are most often affected by a lesion of the eleventh dorsal segment are: small intestine, vermiform appendix, cecum, ovaries, testes, kidney, spleen, ureter, prostate, epididymus, Fallopian tubes, and suprarenal capsules. Much of these connections are made via the lesser splanchic nerve as well as connections via the renal plexus. As with any other segment the effects of a lesion will be determined by whether they are inhibitory or excitatory to the nerve controlling the area in question. Generally, as has been noted before, a flexion/increase in size of the intervertebral foramen (whether unilateral or bilateral) will be excitatory while extension/decrease in size of the intervertebral foramen (unilateral or bilateral) is usually inhibitory.
Keeping in mind that the eleventh dorsal segment is a transitional vertebrae with a high degree of movement freedom it is easily susceptible to developing a lesion. Instead of sticking simply with Marion Clark’s work I am going to jump on my own soapbox (as I have done before) and put some of my thoughts out there (as always, remember that I have a lifetime of learning Osteopathy ahead of me and my thoughts will become more refined as time passes). As I noted in my post on the twelfth dorsal segment, the thoraco-lumbar junction is a big deal in locomotion/propulsion of the human body. The thoraco-lumbar junction is where the upper and lower gridles meet and, as such, the site of coordination. Within this coordination there is the need to manage global balancing of movements as well as transmission/amplification of force between the upper and lower girdle. The thoraco-lumbar junction is extremely important for full body function! To deal with lesions of the eleventh dorsal segment it is imperative that the upper and lower girdles are appropriately adjusted and coordinated.
Another consideration that I wish to postulate is the influence that the thoraco-lumbar junction has on global fluid dynamics. Not only does correcting the thoraco-lumbar junction have the possibility to balance long diagonal torsions that will compress blood and lymphatic vessels, the thoraco-lumbar junction is also closely related to the respiratory diaphragm. The respiratory diaphragm is the prime driver of passive circulation via the respiratory pump. Removing long diagonal torsions as well as correcting the eleventh dorsal segment allows for optimal global fluid flow! As a quick consideration think of all of the blood and lymphatic vessels that pass through the respiratory diaphragm (also consider the digestive structures that pass through it!). Don’t forget the importance of the kidneys with regards to full body fluid regulation as well as the close relationship they have with the thoraco-lumbar junction!