| disease | Prolapse of Lumbar Intervertebral Disc |
| alias | Lumbar Disc Annulus Fibrosus Rupture Nucleus Pulposus Prolapse |
As early as 1764, Contugno described the symptoms of lumbar intervertebral disc herniation. In 1857, Virchow reported a case, and in 1896, Kocher discovered a case of lumbar intervertebral disc herniation caused by trauma. In 1911, Middleton and Teacher reported a fatal case due to nerve root compression from prolapse of the lumbar intervertebral disc. That same year, Good-Thwait explained the relationship between prolapse of the lumbar intervertebral disc and sciatica. Between 1928 and 1929, Schmorl and others linked degenerative changes in the lumbar intervertebral disc to herniation of the intervertebral disc. In 1934, Mixter and Barr reported successful surgical removal of a herniated lumbar intervertebral disc with excellent results. Subsequently, scholars both domestically and internationally began performing lumbar discectomies and conducted in-depth research on prolapse of the lumbar intervertebral disc. Today, this condition is widely recognized by scholars worldwide and is believed to be closely related to 95% of sciatica cases and 50% of lower back and leg pain cases, as well as potentially causing secondary lumbar spinal stenosis.
bubble_chart Etiology
After adolescence, degenerative changes occur in various tissues of the human body, among which intervertebral disc degeneration occurs relatively early. The primary change is the dehydration of the nucleus pulposus. After dehydration, the intervertebral disc loses its normal elasticity and tension. On this basis, due to severe trauma or repeated minor {|###|} injuries, the annulus fibrosus weakens or ruptures, allowing the nucleus pulposus to herniate from that site.
The nucleus pulposus often protrudes posterolaterally into the spinal canal from one side (rarely from both sides simultaneously), compressing the nerve roots and causing symptoms of nerve root {|###|} injury. It may also herniate centrally backward, compressing the cauda equina and leading to urinary and fecal dysfunction. If the annulus fibrosus completely ruptures, fragmented nucleus pulposus tissue can enter the spinal canal, causing widespread damage to the cauda equina. Due to the heavy load and frequent movement in the lower back, herniation commonly occurs at the L4-5 and L5-S1 intervertebral spaces.
bubble_chart Clinical Manifestations(1) Lumbago and radiating pain in one lower limb are the main symptoms of this disease. Lumbago often occurs before leg pain, or both may occur simultaneously; most cases have a history of trauma, but some may have no clear predisposing factors. The pain has the following characteristics:
1. The radiating pain travels along the sciatic nerve, reaching the lateral side of the lower leg, dorsum of the foot, or toes. If the herniation occurs at the L3-4 level, compression of the L4 nerve root causes radiating pain in the anterior thigh.
2. Any action that increases cerebrospinal fluid pressure, such as coughing, sneezing, or defecation, can worsen lumbago and radiating pain.
3. Pain worsens with activity and improves with rest. Bed posture: Most patients adopt a lateral position with the affected limb flexed; in severe cases, pain persists in any posture, and the patient may only find relief by kneeling with hips and knees flexed. Those with concurrent lumbar spinal stenosis often exhibit intermittent claudication.
(2) Spinal scoliosis deformity: The main curvature is in the lower back and becomes more pronounced when bending forward. The direction of the curvature depends on the relationship between the herniated nucleus pulposus and the nerve root: if the herniation is anterior to the nerve root, the torso generally bends toward the affected side.
Left: If the herniated nucleus pulposus is located anteromedial to the nerve root, the spine bends toward the affected side, and bending toward the healthy side exacerbates the pain.
Right: If the herniated nucleus pulposus is located anterolateral to the nerve root, the spine bends toward the healthy side, and bending toward the affected side exacerbates the pain.
(4) Tenderness in the lumbar region with radiating pain: There is localized tenderness on the affected side near the spinous process at the site of herniation of the intervertebral disc, accompanied by radiating pain to the lower leg or foot, which is significant for diagnosis.
(5) Positive straight leg raise test: Due to individual constitutional differences, there is no uniform degree standard for a positive test, and comparison between both sides is important. Limited elevation of the affected leg with radiating pain to the lower leg or foot is considered positive. Sometimes, raising the healthy leg causes numbness or pain in the affected leg due to traction on the affected nerve, which is highly valuable for diagnosis.
(6) Neurological examination: In L3-4 herniation (compression of the L4 nerve root), the knee reflex may diminish or disappear, and sensation on the medial side of the lower leg may decrease. In L4-5 herniation (compression of the L5 nerve root), sensation on the anterolateral lower leg and dorsum of the foot decreases, and extensor hallucis longus and second toe muscle strength often weaken. In L5-S1 herniation (compression of the S1 nerve root), sensation on the posterolateral lower leg and lateral foot decreases, muscle strength of the third, fourth, and fifth toes weakens, and the Achilles reflex diminishes or disappears. Severe nerve compression may lead to muscle atrophy in the affected limb.
bubble_chart Auxiliary Examination
Anteroposterior and lateral views of the lumbosacral spine should be taken, with oblique views added if necessary. Scoliosis is often present, and sometimes narrowing of the intervertebral space or lipping of the vertebral margins may be seen. Although radiographic findings cannot serve as definitive evidence for the diagnosis of {|###|}prolapse of lumbar intervertebral disc{|###|}, they can help exclude other conditions such as lumbar {|###|}subcutaneous node{|###|}, {|###|}osteoarthritis{|###|}, {|###|}fracture{|###|}, tumors, or spondylolisthesis. For severe or atypical cases where diagnosis is difficult, special examinations such as myelography with iodized oil, CT scans, or magnetic resonance imaging may be considered to confirm the diagnosis and locate the herniation. Patients with no significant abnormalities on these tests cannot completely rule out {|###|}herniation of intervertebral disc{|###|}.
Most patients with {|###|}prolapse of lumbar intervertebral disc{|###|} can be accurately diagnosed based on clinical symptoms or signs. The main symptoms and signs are: ① {|###|}lumbago{|###|} combined with "{|###|}sciatica{|###|}" radiating to the lower leg or foot, with a positive straight-leg raising test; ② marked tenderness lateral to the interspinous ligament at L4-5 or L5-S1, accompanied by radiating pain to the lower leg or foot; ③ decreased skin sensation in the anterolateral or posterolateral lower leg, weakened toe muscle strength, and diminished or absent Achilles tendon reflex on the affected side. X-rays can exclude other bone {|###|}sexually transmitted disease{|###|} changes.
bubble_chart Treatment Measures
(1) Non-surgical treatment: Resting on a hard board bed, supplemented with physical therapy and tuina, can often alleviate or cure the condition. There are many traction treatment methods. The prone traction and shaking reduction is a reduction method summarized from Chinese medicine manipulation techniques. An automatic traction and shaking machine has now been developed, the therapeutic principle of which is to separate the intervertebral space and apply rhythmic shaking at the site of herniation of intervertebral disc to reposition the prolapsed nucleus pulposus. This method is suitable for prolapse of lumbar intervertebral disc without bone sexually transmitted disease changes, without major incontinence of urine, and without systemic diseases. Before treatment, it is not advisable to eat a full meal to avoid abdominal distension and fullness. After treatment, strict bed rest for one week is required. If symptoms are not relieved after one session, traction and shaking can be repeated after a few days of rest. This method is simple, has a high cure rate, is easily accepted by patients, and is a commonly used non-surgical therapy.
(2) Surgical treatment
The indications for surgery are: ① Failure or recurrence of non-surgical treatment, with severe symptoms affecting work and life. ② Obvious and extensive symptoms of nerve injury, or even worsening, with suspected complete rupture of the intervertebral disc annulus fibrosus and herniation of nucleus pulposus fragments into the spinal canal. ③ Central lumbar herniation of intervertebral disc with dysfunction of bowel and bladder. ④ Combined with obvious lumbar spinal stenosis.
Preoperative preparation includes X-ray localization, which involves marking the area of obvious tenderness and radiating pain with methylene blue and fixing a metal marker at the site with adhesive tape, then taking an anteroposterior lumbar X-ray for intraoperative reference.
The surgery is performed under local anesthesia. The ligamentum flavum and part of the lamina above and below the affected area are removed, and the spinal dura membrane and nerve roots are gently retracted to expose the herniated intervertebral disc. A long-handled knife is used to circumferentially incise the annulus fibrosus of the herniated portion, which is then removed. A pituitary rongeur is inserted into the intervertebral space to remove residual degenerated nucleus pulposus tissue. The wound is irrigated, and after complete hemostasis, it is sutured. The operation must be meticulous, with attention to hemostasis during surgery to prevent nerve injury. Postoperatively, gentamicin is injected into the spinal canal to prevent intervertebral space infection. Before closing the wound, a rubber tube is placed for drainage.
Generally, only one intervertebral space is exposed during surgery. However, if preoperative diagnosis indicates herniation at two sites or no abnormality is found at one exposed site, another space may be exposed. For patients with combined lumbar spinal stenosis, in addition to discectomy, adequate decompression should be performed based on the degree of spinal stenosis. Since the surgery is performed using the laminotomy or laminectomy method, it does not affect spinal stability. Patients can get out of bed and move around 3 days after surgery, with rapid functional recovery, and can resume light work in 2–3 months. Heavy physical labor should be avoided within six months postoperatively.
(1) Lumbar Facet Joint Disorder The adjacent vertebral bodies' superior and inferior articular processes form the lumbar facet joints, which are synovial joints with nerve distribution. When the relationship between the superior and inferior articular processes is abnormal, acute cases may experience pain due to synovial membrane impaction, while chronic cases may develop traumatic arthritis of the facet joint, leading to lumbago. This pain often occurs 1.5 cm lateral to the spinous process and may radiate to the ipsilateral buttock or posterior thigh, easily confused with prolapse of lumbar intervertebral disc. The radiating pain from this condition generally does not extend beyond the knee joint and is not accompanied by signs of nerve root damage such as sensory loss, muscle weakness, or reflex absence. For difficult-to-diagnose cases, injecting 5 ml of 2% procaine near the affected facet joint can help exclude prolapse of lumbar intervertebral disc if symptoms disappear.
(2) Lumbar Spinal Stenosis Intermittent claudication is the most prominent symptom. Patients report lower limb soreness, numbness, and weakness after walking a certain distance, requiring squatting to rest before continuing. Cycling may not cause symptoms. Another key feature is that patients often have many complaints but few objective signs. A minority may exhibit signs of radicular nerve injury. Severe central stenosis can lead to urinary incontinence. Special tests like myelography with iodized oil or CT scans can confirm the diagnosis.
(3) Lumbar Subcutaneous Nodule Early localized lumbar subcutaneous nodules can irritate nearby nerve roots, causing lumbago and radiating leg pain. Lumbar subcutaneous nodules present systemic reactions of nodular disease, with severe lumbago. X-rays may show destruction of the vertebral body or pedicle. CT scans are particularly useful for detecting early localized subcutaneous nodule lesions not visible on X-rays.
(4) Vertebral Metastasis Pain intensifies, worsening at night, with patients showing constitutional weakness. Primary tumors may be identified. Plain X-rays reveal osteolytic destruction of the vertebral body.
(5) Spinal Meningioma and Cauda Equina Tumor These are chronic progressive conditions without intermittent improvement or spontaneous recovery, often accompanied by urinary incontinence. Cerebrospinal fluid protein levels are elevated, and Queckenstedt's test indicates obstruction. Myelography can provide a definitive diagnosis.
