Herniated disc is a medical condition caused by ruptured fibrous ring allowing nucleus pulposus to bulge out and oppress nerve root, and its main symptom is pain in waist and lower limbs. Disc herniation usually occurs in waist and neck due to sudden change of loads on spine. Lumbar disc herniation is more commonly seen. After the age-related degeneration of all the parts of lumbar disc (nucleus pulposus,fibrous ring and cartilage plate), especially the nucleus pulposus, with influence of external factors, the fibrous ring may rupture and nucleus pulposus bulge out or even come off into the spinal canal and stimulate or oppress the spinal nerve root nearby, hence symptoms such as pain in the waist, numbness, tingling and pain in one or both limbs occur. Lumbar disc herniation mostly occur between L4-5 and L5-S1, about 95% morbidity. Patients mainly range from 20-40 years old, and male patients are more likely to be affected, the morbidity ratio between male and female is around 2:1. Morbidity of lumbar disc herniation is related to gender, age, occupation characteristics, trauma history and history of getting cold.
Pathogenesis of Lumbar Disc Herniation
- 1.Basic factor:degeneration of lumbar disc
- 3.Weakness of lumbar disc from anatomy
- 4.Genetic factor
- 5.Congenital abnormality of lumbosacral region
- 6.Precipitating factor
Degeneration of nucleus pulposus is mainly seen in water content reduction, which may cause localized pathological changes such as instability and looseness of vertebra segments; degeneration of fibrous ring is mainly seen in the decrease of tenacity.
Repeating external force in long term will cause minor damage, increasing degeneration.
Spinal discs in adult body gradually lost blood circulation and self-repairing ability. With all the factors above, some precipitating factor which increase the pressure of spinal disc may allow the nucleus pulposus with poor elasticity to get through the degenerated fibrous ring and cause herniation of the nucleus pulposus.
There are reports showing that lumbar disc herniation runs in family.
The congenital abnormality includes lumbar sacralization, sacral lumbarization, deformity of hemivertebral body, Asymmetry of zygopophysis, etc. The factors above may change the stress of lumbar vertebra and increase the internal pressure of intervertebral disc as well as the danger of degeneration and trauma.
With spinal disc degeneration, factors which could induce the sudden rise of intervertebral pressure may cause herniation of the nucleus pulposus. Common precipitating factors are increase of abdominal pressure, poor waist posture, sudden weight-bearing, pregnancy, getting cold and dampness.
Symptoms of Lumbar Disc Herniation
- 1.Pain in the waist
- 2.Radiating pain in the lower limbs
- 3.Symptoms of oppressed cauda equina
This is the first symptom for most patients, with an incidence rate of 91%. Since the outer layer of fibrous ring and posterior longitudinal ligament are stimulated by nucleus pulposus, through sinuvertebral nerves caused referred pain in the waist, sometimes accompanied by pain in the hips.
Although lumbar disc herniation in high level (L2-3,L3-4) could cause femoral neuralgia, but clinically it is rarely seen, the incidence rate is less than 5%. Most patients’ herniation are in L4-5, L5-S1, with the symptoms of sciatica. The radiating pain is always on one side of the limbs, only very few central type or near central type of herniation patients suffer from pain in both limbs.
Nucleus pulposus bulged to the rear part or prolapsed or dissociated from the disc tissue and oppress cauda equina will mainly cause fecal and urinary dysfunction as well as perineum and crissum paresthesia. Severe patients may even have symptoms such as feces and urine incontinence and incomplete paraplegia in both lower limbs, which are rarely seen.
Diagnosis of Lumbar Disc Herniation
Combining patient’s medical history, physical examination and imageological examination, it is not difficult to diagnose typical cases of lumbar disc herniation, especially nowadays with the spreading of CT and MRI technology. But it cannot be diagnosed only by features in CT and MRI without any clinical symptoms.
Treatment for Lumbar Disc Herniation
- 1.Stem cell transplantation therapy.
- 2.Non-surgical treatment
- 3.Percutaneous lumbar diskectomy/nucleus pulposus laser vaporization prostatectomy
- 4.Surgical treatment
With repeated clinical treatments, it is proved that transplanting stem cells to the focus area can effectively reduce and treat symptoms of lumbar disc herniation. This therapy is suitable for young patients’ initial attack or patients with a shorter course of disease, mild symptoms and are not qualified for surgical treatment.
Non-surgical treatment is mainly suitable for: ①patients who are young, having initial attack or a short course of disease; ②patients who have mild symptoms and feel relieved after a good rest; ③patients who has no clear spinal canal stenosis according to imageological examination.
This treatment is suitable for patients who has bulged nucleus pulposus or mild herniation, and it is not suitable for patients with lateral recess stenosis, obvious herniation or nucleus pulposus already inside the spinal canal.
Surgical indications: ①patients whose disease history is longer than 3 month, and strictly accepted conservative treatment but received no effect, or patients who has effect from conservative treatment but suffer from often relapse and severe pain; ②patients who are having initial attack but suffer from severe pain, especially from the lower limbs, and cannot move and sleep, be in forced posture; ③patients who also have symptoms of oppressed cauda equina; ④patients who have symptoms of single nerve root palsy along with muscle atrophy and muscle weakness; ⑤patients who also have spinal canal stenosis.
Prevention for Lumbar Disc Herniation
Lumbar disc herniation is caused by accumulation of injury upon degeneration, and these injuries will deepen degeneration of the disc, so the focus of prevention lies in reduction of injury accumulation. People need to keep a correct sitting posture, and should not sleep in too soft beds. People who need to sit in front of a desk and work for a long time need to pay attention to the height of tables and chairs, and regularly change postures. For people who need to bend over a lot during work, it is necessary for them to regularly straighten back and square shoulders, and use wider belts. Increasing lumbodorsal muscles exercises and enhancing the internal stability of spine is very helpful, especially for long-term waist band users, these exercises prevent the adverse outcomes of disuse muscle atrophy. When bending over, it is better to use hips or knees instead of waist, hence reducing pressure behind lumbar discs.