The causes of low back pain are extremely complex, and disorders of the annulus fibrosus, end plate, and paravertebral muscle ligaments may all be causes of low back pain. The anatomical localization of low back pain is vague, which makes clinical diagnosis and treatment very difficult. The intervertebral disc is an important source site of low back pain. Low back pain caused by intervertebral discs is called discogenic low back pain and may be accompanied/unaccompanied by radiating pain in the lower extremities. Low back pain is caused by rupture within the normal structure of the disc and biochemical changes within the disc. It is estimated that 26-39% of chronic low back pain is caused by intradiscal rupture.
Diagnosis of discogenic low back pain
I. Diagnosis of discogenic low back pain
The history, symptoms and signs of discogenic low back pain are atypical. The diagnosis of discogenic low back pain is currently made mainly by discography-induced pain experiments. Reproduction of similar or consistent pain during discography is the most reliable sign for the diagnosis of discogenic low back pain. Discography CT can better visualize the internal structure of the disc and therefore helps to make a pathological diagnosis of the pain-causing disc in patients with discogenic low back pain. high signal areas and Modic changes in the end plate on MRI are only useful imaging signals as an aid to the diagnosis of discogenic low back pain due to their poor specificity.
II. Differential diagnosis of discogenic low back pain
Acute lumbar sprain
1, clear history of trauma.
2.pressure pain at the attachment point of lumbar back muscles.
3.After local muscle closure, pain is relieved.
4.Straight leg raising test is negative.
Chronic lumbar strain injury
1.Chronic strain pain, part of them have a history of acute trauma.
2.Soreness or dull pain in the low back after exertion, which may involve the buttocks or the back of the thigh.
3.It can be relieved by rest, but not completely relieved.
4.The general movement of the lumbar region is not restricted, and the straight leg raising test is negative.
Lumbar intervertebral disc herniation
1.History of low back pain and sciatica.
2.Most patients can make localized diagnosis through physical examination.
3, Positive findings corresponding to clinical symptoms and signs were found by imaging examination.
Small joint pain in the lumbar spine
1, accounting for 15-45% of patients with lumbar pain, most commonly L4-L5 and L5-S1.
2, Lumbosacral pain with or without sciatica. Pain occurs after trunk rotation or twisting, and lumbar pain may radiate to the buttocks or thighs.
3.Small joint pain cannot be reliably diagnosed by clinical manifestations, imaging and physical examination.
4.Diagnostic small joint nerve block can effectively, sensitively and specifically diagnose small joint type low back pain.
Sacroiliac joint pain
1, It accounts for 13-30% of all patients with low back pain and often shows L5 nerve root symptoms and signs.
2, usually with a history of fall or high-speed traffic injuries.
Ankylosing spondylitis
1, 90% of the cases are distributed under the age of 40 years especially in young people aged 18-28 years.
2, low back pain and lumbar stiffness lasting for more than 3 months and not relieved by rest.
3.There is stiffness in the early morning, and the lumbar movement is limited.
4.Hunchback and flexion deformity in the middle and late stage.
5.X-ray film, CT scan suggest inflammatory signs of sacroiliac joint and spinal changes.
6.Serum HLA-B27 positive. Erythrocyte sedimentation rate and serum alkaline phosphatase are increased.
Lumbar spinal stenosis
1. Atypical low back pain, which may further develop into lower limb radiating pain. It is aggravated by standing, walking or activity and relieved by lumbar forward flexion, squatting or seating.
2. Intermittent claudication. The patient finds that the walking distance becomes shorter and shorter.
3.Severe symptoms, while physical examination is often mild or negative.
4.Lumbar posterior extension is limited, which may aggravate the pain.
5.Imaging suggests significant narrowing of the spinal canal and nerve compression.
Lumbar spondylolisthesis
1.Lumbar back pain, instability and downward sensation. Sometimes it is accompanied by nerve root signs, and the symptoms can be relieved by lying down.
2.Palpation of the lumbar back can reveal local depression or step sensation, and local muscle tension.
3.X-ray examination: front and side, left and right oblique and power position films show isthmic fissure and slippage of vertebral body.
Treatment of discogenic low back pain
The treatment of discogenic low back pain aims to relieve or relieve pain, improve function and quality of life, and stop further injury and instability of the lumbar region.
I. Conservative treatment
Conservative treatment is effective in 68% of patients.
Second, spinal fusion
For those patients with persistent low back pain and conservative treatment is ineffective, most of them need surgical treatment. At present, surgical spinal fusion is still the most commonly used treatment and is currently the last option for the treatment of discogenic low back pain. (Figure 9) The painful disc, the segment to be fused, and the surgical approach need to be defined prior to surgical fusion. The goal of surgical fusion of a diseased segment in patients with discogenic low back pain is to remove the diseased disc, remove the source of pain, stabilize the lumbar spine, and provide symptomatic relief. Although many studies have been reported in support of fusion surgery, and the fusion approach has undergone many improvements. However, after fusion of the lumbar spine, accelerated degeneration of the adjacent segments has occurred.
Third, power internal fixation
Surgical fusion of diseased lumbar segments is a common treatment for some patients with severe discogenic lower back pain for whom conservative treatment has failed. Recent studies have found that internal fixation that preserves motion improves lower back pain more than those that restrict motion, which provides a new way of thinking about the treatment of lower back pain. A new concept of “powered internal fixation” or “soft fixation” has been proposed.
Definition of dynamic internal fixation
A fixation system that preserves beneficial motion and intersegmental load transfer without fusion of the vertebral segments. This fixation system prevents lumbar motion in the direction and plane of motion that produces pain, but preserves all other normal lumbar mobility.
IV. Minimally invasive treatment
Intradiscal drug injection; radiofrequency technique; lateral posterior endoscopic technique.