Back pain is usually multifaceted and can be generated not only from a discogenic source but also from facet joints, sacroiliac joints, or just frank muscle spasms, to name a few.
Even though the MRI does not reveal "pinched nerves" or spinal stenosis, this does not eliminate the fact that a disk can be injured and "leaky." The internal contents of the disk are highly inflammatory and can cause radicular symptoms.
I have seen several cases of facet pain radiating pain into the buttocks and posterior thigh. I have also seen several cases of sacroiliac joint pain radiating pain into the buttocks and posterior thigh. A very thorough physical exam needs to be performed in order to sort out the painful structures. Diagnostic and therapeutic injections may also prove helpful in that once an injection is attempted and symptoms improve the character of the pain may change, pointing to another painful source.
It is not uncommon to see a combination of facet and diskogenic pain as well as facet and sacroiliac joint pain or a combination of all three. This is where diagnostic and therapeutic injections become extremely helpful in sorting out and managing back pain.
This is a typical lumbar spine presentation. This young woman not only has back pain but a burning sensation down the back of both legs. Her pain waxes and wanes, ranging from 3-7 on a scale of 1-10 with 10 being the worst. She has tried anti-inflammatory medication and a muscle relaxant without much benefit. Her symptoms are worse with prolonged sitting but tend to improve with walking. She is tender to palpation of the lumbar spine and paraspinal muscles and has limited lumbar flexion. It appears the neurological exam is intact.
With a diagnosis of acute low back pain, probably from diskogenic disease, there are different approaches that may be considered. In the first 30 days 80%-90% of back pain resolves on its own whether treated with medication, injection, chiropractic care, or nothing at all. During acute exacerbation the pain can be severe and measures should be taken to make the patient more comfortable. The use of anti-inflammatory medication and muscle relaxants can prove helpful in getting the patient through the acute phase of the injury.
If the back pain does not respond to medication, chiropractic care and physical therapy may also provide significant relief. Involvement in chiropractic or physical therapy for McKenzie maneuvers to centralize pain followed by advancement to a spine stabilization program may also be beneficial. No matter what treatment is provided, it is my opinion that all spine pain exacerbations should be followed by a spine stabilization program. Substitution with different class anti-inflammatory medication and muscle relaxants may prove to be beneficial if the first medications tried do not provide relief or are not tolerated.
If conservative management fails to improve symptoms I would start with diagnostic and therapeutic epidural steroid injections with either an intralaminar approach or a transforaminal approach. If radiculitis is affecting the nerve roots there would very likely be improvement in pain. If the patient had only low back pain I would be less optimistic that epidural steroid injection would help.
Depending on the results of that injection I would move to diagnostic and therapeutic facet and sacroiliac joint injections if needed. In my opinion, all these injections should be performed under fluoroscopic guidance to confirm placement of the needles and medication.
If the above measures fail and there continues to be a significant amount of back pain then consideration for provocative diskography should be make. This is the gold standard for diagnosing diskogenic back pain. In the past treatment options were typically lumbar fusion. We also have the option of intradiskal electrothermal coagulation (IDET) which is showing promise in the management of diskogenic back pain. In my opinion, diskography, IDET, or fusion should be performed only if all other conservative measures and injections have failed.