Generally, when low back pain is associated with minimal leg pain, we do not know the exact cause. (1) Potential causes include:
- Muscles around the spine,
- Ligaments that hold the spine together,
- Facet joints that keep the spine aligned
- Combination of the above
- Mind Body Syndrom
Physicians can make an exact diagnosis only about 15 percent of the time. Your body is designed to hurt whenever a tissue is injured, so when you feel low back pain, it indicates that the stress threshold for a specific part of the spine has been exceeded. At a minimum, treatment should decrease stress to the whole lower back, so any injured structure can heal.
The diagnosis will also vary depending on what type of spine care provider you are seeing. For example, a rheumatogist may call your pain fibromyalgia. An internist, physiatrist, neurologist, or family practitioner may call it “myofascial pain.” Fascia is the tissue that envelops and defines muscles. The chiropractor might conceptually treat your pain in the context of alignment or vertebral subluxations. A surgeon may feel that the pain is “discogenic.” None of the practitioners are clearly wrong. It is just that it is beyond our current diagnostic abilities to come up with a more exact diagnosis.
Sometimes, a diagnosis is subjective. I don’t definitively know where your back pain is coming from either. My rheumatologist colleague feels LBP is primarily from “inflammation.” My belief, in most cases, is that it is most likely myofascial. Essentiallt, I think the supporting soft tissues around the spine is the cause of non-specific back pain. During my residency, I had a belief that since the only “real joint” in the spine is the facet joint, pain must be coming from the facet joints. From 1986 to 1993, I had the strong impression that most back pain must be originating from the discs. My treatment offers during my “discogenic years” usually consisted of aggressive fusions for low back pain.
I have often wondered aloud to my colleagues what percent of patients with a “discogenic” low back pain diagnosis in a surgeons’ office would have a fibromyalgia diagnosis from a rheumatologist. (Fibromyalgia is not a surgically treatable problem; is it a coincidence that surgeons don’t often come up with this diagnosis?)
The upshot is that undergoing a permanent major structural alteration to your spine based on a “possible” source of the pain is unpredictable and risky.
1. Nachemson, A. Advances in low-back pain. Clinical Orthopedics and Clinical Research 1985; 200: 266-278.