Can I have a pinched blood vessel ?

Patients will often precede a question with the disclaimer “ this may be a dumb question, but I am wondering if….”. This disclaimer almost always guarantees that they are usually pretty astute in their observation and closing in on some matter of importance.

The latest “dumb question” that came up this week was interesting: could my symptoms be caused by a pinched blood vessel ?  The patient had some pins and needles sensations in the front of the shoulder, they had noticed that the skin on the front of the arm was a little darker and a little colder than on the other side. Good logic led them to wonder if there was decreased blood flow in the affected area.

The surprising answer to that question is not only: yes !, but the fact that most instances of pinched nerves probably have some degree of pinched vascular structures that go along with the pinched nerve. And there is a very simple reason for that: if you go back to basic anatomy, nerves, arteries and veins very often travel as a trio before splitting off prior to their final destination. Anyone who has done college level anatomy will recall the acronym NAV, standing for  nerve, artery and vein, describing the bundles of the three structures lumped together. And anyone who has done anatomy cadaver dissection recalls how difficult it was to separate the three structures from each other and tell them apart.

From a practical and clinical standpoint, there is a lot of overlap in the symptoms of nerve and vascular compression. Both can cause pain, and both can cause abnormal sensation like numbness and tingling, making it difficult to differentiate them based on symptoms alone. Physical examination can be helpful, but also somewhat limited. Mild vascular compression can cause subtle swelling, changes in color and temperature, but those can be difficult to differentiate from inflammation related edema, and most body areas have collateral circulation that can take over when there is mild vascular compression from one source. 

In day to day chiropractic practice, we tend not to aim our treatment to relieve mild vascular compression independent from relieving nerve compression, which is probably why we talk about this topic infrequently. Relieving nerve compression is the main goal, and vascular structures will basically benefit from that approach. Nerve tissue and vascular tissues have distinct features that makes nerves more vulnerable in NAV bundles: they lack collateral back up, and they are not as adaptable to move out of the way of compressive forces. But that is not to say that some patients will show up with unusually strong vascular compression symptoms that need to be taken into account when setting up a treatment plan, for example limiting the use cold pack therapy and compression

Femoral neuritis: the "other sciatica"

Femoral Neuritis

Sciatica enjoys quite a bit of popularity, and rightfully so. It is not technically a medical diagnosis but the description of symptoms encompassing pain in the leg, generally assumed to stem from the low back. The sciatic nerve originates at 5 levels spanning the last two lumbar vertebrae/discs, and the upper three sacral segments. It travels through several soft tissue structures in the buttock, down the posterior thigh, before splitting into two different branches at the knee, covering the lateral and posterior calf and foot. As such, sciatica describes referred pain affecting this distribution pattern.

Patients often use the term “sciatica” pretty liberally, to describe any sort of pain in the leg, including pain in the front of the thigh, which is not a sciatic nerve distribution. Enter its lesser known cousin, the femoral nerve.

Femoral neuritis is actually surprisingly common but getting little recognition ( it is still less common than sciatic neuritis). The femoral nerve originates in the mid lumbar spine and is made up from nerve roots from lumbar segments L2 through L4.  It travels in the front of the lumbar spine, deep in the abdomen, through the intersection of the two branches of the iliopsoas hip flexor muscles, through the groin and into the anterior and medial aspect of the thigh. It does not extend very far below the knee, unlike the sciatic nerve, which extends all the way into the foot.

The femoral nerve can be compressed in the lumbar spine, by a mid lumbar disc herniation, and just as commonly by myofascial injuries in the hip flexors. The patient will often present with unexplained groin, hip, thigh and medial knee pain and tingling. Unlike sciatic neuritis, many patients will not initially recognize  femoral neuritis as referred pain from the lumbar spine since it manifests in the front of the trunk and leg.

Femoral neuritis will be treated in the same manner as sciatic neuritis, based on the source / cause of the problem: chiropractic adjustments, myofascial release, corrective exercise, supportive therapies etc.

Can the low back cause abdominal pain ?

It's a question that has been posed to me on a couple of occasions. Obviously, abdominal pain can have many pain generating structures, and internal abdominal organs are going to be the primary source of pain. However, I have had many a case over my 30 years in practice where a patient came in with persistent vague lower abdominal discomfort that felt really deep, and had had a battery of tests from ultrasounds, endoscopies, colonoscopies, and a boatload of labs, without any explanation for the continued symptoms. In the process of working up the patient for some other symptoms (lower back with thoracic pain most commonly), the patient reports a substantial improvement in their long-standing abdominal pain when starting chiropractic care.

An older and wiser colleague who mentored me in my early career once said: "there is as much lumbar spine in the front as there is in the back". The point was that the posterior aspect of the lumbar spine gets the lion's share of attention, since the posterior structures such as the facet joints, and the posterior margin of the lumbar discs, have a higher density of fine discriminating pain sensors, and all the spinal nerves which exit posterior to the center of the vertebral body can basically only be compressed in the posterior half of the lumbar spine. However, this is not to say that anterior lumbar pain generating structures do not exist or that they are rare. Anterior lumbar disc herniations are clearly seen on MRIs. They do not often get the attention they deserve, since orthopedic and neurosurgical providers are more focused on spinal nerve compression. Anterior lumbar disc herniations and the pain they generate is going to be more vague, and have more of an autonomic pain component: pain, malaise, nausea, fatigue, cold sweats, etc. One of the distinguishing features of abdominal pain of anterior lumbar origin is that it is going to be triggered by positional and mechanical factors much more so than digestive triggers. In this scenario, a thorough chiropractic examination is certainly worth investigating if you or a loved one has been dealing with continued unexplained abdominal pain that has been medically investigated with no answers.

( image courtesy of Freepik)

DORSAL SCAPULAR NEURALGIA

In this discussion I would like to explore an extremely common pain pattern as well as some of the root causes and treatments available.

Many patients will present with pretty intense pain in the inside of the shoulder blade, radiating downward in a "J" pattern that hooks underneath the inferior corner of the shoulder blade. The pain is often an ill-defined deep dull achy sensation that the patient feels starts in the mid back area but is difficult to pinpoint.

When patients manually trace the location and radiation of this type of pain, they're basically describing the path of the dorsal scapular nerve without having ever rather than anatomy book.

The dorsal scapular nerve is a relatively thin but long nerve that is formed by a branch of the spinal nerve exiting around the C5 vertebra it then has a convoluted pathway that has to travel through the metal scaling muscles, underneath the levator scapula muscle, and underneath the rhomboid muscles before tapering off at the bottom of the scapula.

The relatively long and convoluted path of the dorsal scapular nerve makes it particularly vulnerable to single or multiple areas of compression with the resulting pain described by the patient above. Possible areas of entrapment include: at the level of the spine itself around C5, especially common from reverse cervical curves and whiplash type injuries, in the scalenes, underneath the levator scapula which is a muscle chronically activated by anterior cervical posture, and within the rhomboid muscles, which are also very chronically partially overloaded muscles.

If the source of the entrapment and compression to the dorsal scapular nerve happens to be within the rhomboids, the patient will usually have some degree of luck resolving the issue with local intervention. However some of the patients we see with the most persistent pain pattern of dorsal scapular neuralgia happened to be those patients with entrapment higher up, usually within the mid cervical spine and the scalenes, as the pain can be felt only in the thoracic spine and not alert the patient or the provider to look higher up the nerve source for resolution. The source of the dorsal scapular neuralgia can usually be assessed by manual palpation if carefully applying pinpoint pressure over the area of the C5 nerve root exit, within the middle scalenes, or the levator scapula muscle, and fully reproducing the pain pattern in the thoracic spine. As always, treatment of the problem depends on the location of the problem itself, but for the most part a combination of cervical manual adjustments and specific myofascial nerve entrapment release can usually get the job done.

https://www.youtube.com/watch?v=8cH151cJEaI