Most lumbar disc herniation occurs in one side of the lateral saphenous fossa, causing radiating pain and numbness in one lower extremity, mostly causing pain to patients, and the traditional surgical approach is mainly the posterior median approach to the spine, although most of the results are good, but the original symptoms are not completely resolved after laminectomy and decompression, and there are new symptoms of nerve irritation, as well as a longer period of strong pulling to the lateral side of the stripped vertebral The paravertebral muscle group, which leads to persistent postoperative low back pain, has become a more common complication, and a few patients have postoperative discomfort due to adhesions between the dural sac and muscles.
Clinical data
1.General information
There were 21 cases in this group, 15 males and 6 females, age 35 – 62 years old, average 48 years old. Among them, there were 13 cases of lumbar spine 4 and 5 interspace, 9 cases of protrusion to the left side, 4 cases of protrusion to the right side, 9 cases of lumbar 5 sacral 1 interspace, 5 cases of the left side and 4 cases of each right side. All patients underwent frontal and lateral radiographs of the lumbar spine and lateral radiographs of lumbar hyperextension and hyperflexion as well as MRI examination of the lumbar spine.
2. Surgical approach and surgical method
The patients were operated under general anesthesia with a 2 CM incision next to the spinous process on the affected side in the prone position.
The skin and subcutaneous tissues were incised, and the lumbodorsal fascia was incised longitudinally, and the paravertebral muscles were clearly revealed after incision. The position of the multifidus and longest muscles is determined, and the two muscles are gently and bluntly separated from each other with a periosteal stripper. The surface of the small articular eminence and the transverse prominence of the corresponding vertebral body can be easily reached from superficial to deep, and the transverse prominence of the vertebral body can be determined according to the shape of the transverse prominence, and a fluoroscopic needle is inserted into the vertebral body through the midpoint of the corresponding transverse prominence and the beginning of the articular eminence.
Care is taken not to damage the veins and posterior branches of the spinal nerve that pass through the muscular space. These structures can be clearly exposed by stripping a small amount of surface tissue from the upper and lower tuberosities, the transverse process, and the lateral surface of the vertebral plate without forceful retraction of soft tissues such as the paravertebral musculature.
The ligamentum flavum is revealed in the intervertebral soft tissue space between the upper and lower articular processes, and the ligamentum flavum is peeled off with a small spatula along the upper edge of the vertebral plate of the upper vertebral body and along the lower edge of the vertebral plate of the lower vertebral body, and the canal between the upper and lower vertebral plates without posterior bony structures can be accessed by removing the ligamentum flavum with a 1 cm sharp bone knife and first partially chiseling along the medial edge of the lower articular process of the upper vertebral body to reveal the coronal growth of the upper articular process of the lower vertebral body of the lower examination body. The joint surface of the inferior vertebral body is coalesced, and below it is the lateral saphenous fossa and the near opening of the nerve roots that are extruded by it;
The extent of chiseling is such that the exit and travel roots penetrating this area can be effectively exposed and released, the compressed nerve roots can be decompressed, and the intervertebral space can be clearly revealed. It is not necessary to remove the entire tuberosity, but only the marginal expansions that have migrated sagittally, proliferated, hypertrophied, and coalesced toward the midline during the degenerative process. The nerve roots and dural sac are pulled medially with a nerve root puller to fully expose the herniated or prolapsed disc or nucleus pulposus.
The intervertebral or vertebral body punch is placed in the intervertebral space in front of the dural sac, and the posteriorly protruding nucleus pulposus and fibrous ring tissue or hyperplastic soft tissue are punched into the intervertebral space and again removed with the nucleus pulposus.
After full exploration of the nerve and the dural sac without compression, it was flushed with physiological saline. Temporarily compress with gauze and put in the elastic rod. And put in the transfusion drainage tube to drain, and suture the lumbar dorsal fascia, subcutaneous and skin in layers.
3.Postoperative treatment and observation index
Postoperative application of antimicrobial agent for 3 – 5 days, straight leg raising exercise on the next day after surgery, the patient can be allowed to get out of bed and live a normal life 4 days after surgery. The patient was just told not to perform heavy physical work for 3 months. Comparison of their preoperative and postoperative low back and leg pain scores. Postoperative and preoperative pain scores were: 0 no pain: very painful.
4. Results
All 20 patients in this group had complete disappearance of lower limb pain after surgery, and the mean amount of blood drained after surgery was 50 ML. preoperative and postoperative VAS scores for low back and lower limb pain: preoperative mean was 8. 5, postoperative mean was 1. 0. No discomfort was found to occur in the postoperative follow-up.
5. Discussion
5.1 The importance of the posterior lumbar ligamentous complex
Since 1963, when HOLDSWORTH proposed the posterior ligament complex, which is mainly a component of the posterior column and includes mainly the posterior supraspinous ligament, interspinous ligament, ligamentum flavum and small joint capsule, biomechanical studies have confirmed the stabilizing effect of the posterior ligament complex on the spine.
JAMES et al. concluded that thoracolumbar fractures with intact posterior structures are stable fractures and can be treated satisfactorily by establishing a spinal fracture model, and found that injury to the posterior column plays a more important role in the evaluation of burst fracture stability than injury to the middle column.PANJABI et al. showed that the supraspinous, interspinous, and ligamentum flavum ligaments play a stabilizing role in the spine in flexion, and referred to the posterior The posterior ligament complex is referred to as an “endogenous stabilizing system.”
ASANO et al. demonstrated that the supraspinous and interspinous ligaments have a significant effect on the tension load and tension strength factor, and that the posterior ligament complex is important for maintaining spinal stability.
5.2 Inappropriateness of traditional posterior lumbar surgery: it is obvious that intraoperative exposure requires extensive stripping of the paravertebral muscles, and a long period of continuous pulling and compression with a vertebral plate pulling hook resulting in ischemia of the muscles and injury to the posterior branch of the spinal nerve innervating the paravertebral muscles, and the paravertebral muscles are tightly encircled by thick and tough myofascia, after a longer period of strong pulling;
Postoperative edema leads to ischemia and the occurrence of interfascial compartment syndrome, which triggers postoperative low back pain and muscle atrophy; and the blood supply, metabolism and innervation characteristics of the paravertebral muscle itself make this process last for a longer period of time, and these factors are one of the causes of persistent postoperative low back pain.
The paravertebral muscles have an important role in maintaining the stability and motor function of the lumbar spine. In the posterior median approach, the paravertebral muscles are extensively stripped up and down from the spinous process and the attachment point of the vertebral plate, resulting in a decrease in muscle control of the lumbar spine and a decrease in strength due to the injury to the muscles themselves;
The paravertebral muscles cannot effectively counteract the spinal flexion stress and the dorsal extension force will be significantly reduced, thus causing lumbar instability and increased load, which leads to the occurrence of clinical symptoms such as postoperative lumbar pain, lumbar weakness and lumbar instability.
The disadvantage is that the gap is small when the paravertebral muscle is retracted medially and there is no corresponding pulling hook for retraction, but only the sigmoid pulling hook for abdominal retraction is used.
CONCLUSION: The unilateral elastic nailing of the posterior paravertebral muscle gap access for the treatment of disc herniation has significant efficacy in its postoperative function when economically feasible. The disadvantage is that a pulling hook for inward retraction is not readily available.