Monday, June 10, 2013
Low Back Pain: Where Is My Pain Coming From?
Low back pain can emanate from many anatomical locations (as well as a combination of locations), which always makes it interesting when a patient asks, “…doc, where in my back is my pain coming from?” In context of an office visit, we take an accurate history and perform our physical exam to try to reproduce symptoms to give us clues as to what tissue(s) may be the primary pain generators. In spite of our strong intent to be accurate, did you know, regardless of the doctor type, there is only about a 45% accuracy rate when making a low back pain diagnosis? This is partially because there are many tissues that can be damaged or injured that are innervated by the same nerve fibers and hence, clinically they look very similar to each other. In order to improve this rather sad statistic, in 1995 the Quebec Task Force published research reporting that accuracy could be improved to over 90% if we utilize a classification approach where low back conditions are divided into 1 of 3 broad categories:
1. Red flags – These include dangerous conditions such as cancer, infection, fracture, cauda equina syndrome (which is a severe neurological condition where bowel and bladder function is impaired). These conditions generally require emergency care due to the life threatening and/or surgical potential.
2. Mechanical back pain – These diagnoses include facet syndromes, ligament and joint capsule sprains, muscle strains, degenerative joint disease (also called osteoarthritis), and spondylolisthesis.
3. Nerve Root compression – These conditions include pinching of the nerve roots, most frequently from herniated disks. This category can include spinal stenosis (SS) or, combinations of both, but if severe enough where the spinal cord is compromised (more commonly in the neck), SS might then be placed in the 1st of the 3 categories described above.
The most common category is mechanical back pain of which “facet syndrome” is the most common condition. This is the classic patient who over did it (“The Weekend Warrior”) and can hardly get out of bed the next day. These conditions can include tearing or stretching of the capsule surrounding the facet joint due to performing too many bending, lifting, or twisting related activities. The back pain is usually localized to the area of injury but can radiate down into the buttocks or back of the thigh and can be mild to very severe.