Lumbar Disc Herniation
Last edit by Alaric Steinmetz on
Synonyms: BSV, LDH
Disc herniations can occur in the cervical, thoracic, and lumbar regions of the spine and can also be completely asymptomatic in many cases. By far the most common are lumbar disc herniations, with approximately 95 % affecting the intervertebral disc space between the 4th and 5th lumbar vertebrae (L4/5) and between the 5th lumbar vertebra and the first sacral vertebra (L5/S1). In the vast majority of cases, no surgical intervention is necessary, and only 5-10% of all disc herniations require surgery1. A lumbar disc herniation is almost always preceded by a long history of back pain. When a nerve root is compressed, pain radiating into the buttocks and legs occurs depending on the area supplied by the nerve. The radiating leg pain is usually the predominant symptom and, depending on the level of the disc herniation, may be localized to different areas of the leg. Current evidence shows that both conservative and surgical treatment of disc herniation have their place2.
Diagnosis
The diagnosis of a disc herniation is established by spinal MRI, which is the imaging gold standard. Larger disc herniations can often already be identified on CT, although an MRI must be performed before surgery for more precise assessment. On clinical examination, patients frequently show findings corresponding to the affected nerve root: diminished reflexes, hypesthesia, and a positive Lasègue sign. Very pronounced compression of a nerve root may additionally cause motor deficits in the corresponding nerve distribution.
Conservative Therapy
As a rule, a disc herniation is treated conservatively, with regular outpatient physical therapy being particularly important. In many cases, the disc herniation is displaced or resorbed, and the symptoms regress without the need for intervention. If pain persists despite physical therapy and analgesic medication, an infiltration of the affected nerve root can be performed. A mixture of local anesthetic and corticosteroid is applied directly to the nerve root under imaging guidance using X-ray or CT. The response to epidural nerve root infiltration varies considerably from patient to patient. However, this is a very low-risk minor procedure and should, provided there is no indication for emergency surgery, be part of conservative treatment.
Indication for Surgery
In most cases, disc herniations can be treated conservatively. However, if symptoms persist despite exhausting conservative treatment options, surgical removal of the disc herniation may be performed. The occurrence of significant motor deficits or acute-onset bladder or bowel dysfunction is considered an emergency indication. Cauda equina syndrome Cauda Equina Syndrome is an absolute emergency indication requiring immediate surgical treatment.
Surgical Risks
Disc surgery is a very common neurosurgical procedure, but like any operation, it still carries specific risks.
- Recurrent disc herniation: Because the intervertebral disc space at the level of the existing disc herniation is already damaged, there is a risk of recurrent disc herniation. The incidence of recurrent disc herniation reported in the literature is approximately 7-18 %3.
- CSF fistula: The risk of a CSF fistula is approximately 3.5 % after an initial lumbar disc operation and increases to as much as 13 % during revision surgery due to scarring and adhesions4. If the dura mater is damaged during surgery, this results in a CSF leak. Loss of CSF causes orthostatic headaches. In cases of severe symptoms or CSF leakage through the wound, revision surgery is necessary. If damage to the dura is identified intraoperatively, it is usually closed immediately during the procedure.
- Postoperative hemorrhage: Postoperative hemorrhage can cause a spinal epidural hematoma, which can lead to nerve compression and consequently severe pain and neurological deficits. Symptomatic postoperative hemorrhage should be treated with emergency revision surgery. The risk of postoperative hemorrhage is significantly increased, particularly in patients with coagulation disorders or those taking anticoagulants.
- Nerve injuries: Because the surgery takes place immediately adjacent to the nerve roots, damage to the nerve roots with consequent partial paralysis of the lower extremity is also possible in very rare cases.
- Wound infection: As with any surgical procedure, a wound infection can also occur after disc surgery. If it is not merely superficial but extends into the deeper tissues, this can lead to a very protracted process with spondylodiscitis and the corresponding need for subsequent surgery.
References
Deyo RA. Herniated Lumbar Intervertebral Disk. Ann Intern Med. 1990;112(8):598 ↩ ↩
Schoenfeld A, Weiner B. Treatment of lumbar disc herniation: Evidence-based practice. Int J Gen Med. 2010;3:209-214. ↩ ↩
Watters WC III, McGirt MJ. An evidence-based review of the literature on the consequences of conservative versus aggressive discectomy for the treatment of primary disc herniation with radiculopathy. The Spine Journal. 2009;9(3):240-257. ↩ ↩
Tafazal SI, Sell PJ. Incidental durotomy in lumbar spine surgery: incidence and management. Eur Spine J. 2004;14(3):287-290. ↩ ↩
