Patients who herniate a disc at the L5-S1 lesion face surgery that can be difficult because of the location of the disc and its difficult access. While posterior approaches have been done regularly, an anterior approach, transabdominal is proving to be a viable technique. The authors of this article review the surgical method and evaluate its effectiveness and safety.
Researchers located 30 patients who had undergone transabdominal percutaneous lumbar discectomy (TPLD) for treatment of L5-S1 extruded disc fragments. The patients were, on average, 42 years old. Five patients had undergone surgery previously. All patients had undergone conservative medical treatment but had not been relieved of their pain.
To undergo the procedure, several steps had to be followed. Step 1 involved bowel preparation, which is crucial to obtaining optimal outcome of the surgery. Following the bowel protocol, which evacuated the bowels, the patients received a barium meal that would help the surgeon visualize the bowel. The patients also received metoclopramide to enhance bowel tension, and barium was introduced through the rectum to fill the left colon.
The patients underwent spinal anesthesia as their assistance is needed for this surgery. The discectomy is performed and broad-spectrum antibiotics are injected into the disc space to prevent infection. Evaluation of success begins immediately after surgery with straight leg raises and neurological examination.
After the surgery, the patients were followed for between 12 and 30 months. Their progress was assessed regarding function and pain. Patients filled out a standard spine questionnaire and every three months, x-rays, computed tomography (CT) scans, or magnetic resonance imaging (MRI) were performed. In the case where patients couldn’t be evaluated by the researchers, they were interviewed over the phone regarding their progress or any problems.
The results showed that the TPLD was technically successful and well-tolerated in all patients. Only one patient did not see a resolution of pain or neurological problems and one patient developed pancreatitis. Before surgery, the mean visual analog scale (VAS), measuring the intensity of pain from 0 to 10, with 10 being the most severe, was 7.1. After surgery at the final follow-up, VAS was 0.933. The McNab classification of excellent, no pain, no restriction of activity; good, occasional back or leg pain of sufficient severity to curtail or modify work or leisure activities; fair, improved functional capacity but handicapped by intermittent pain of sufficient severity to curtail or modify work or leisure activities; or poor, no improvement or insufficient improvement to enable an increase in activities and thus further operative intervention required, was used to measure progress. According to the Mcnab criteria, all patients showed good results (26 were excellent and four were good).
The authors wrote that the advantages of this procedure over the traditional approach from the back included avoiding paraspinal muscle trauma and partial denervation, the ability to remove more of the offending disc, which minimizes the possibility of recurrent herniations at that level, less pain after surgery, and earlier discharge from the hospital. They point out that the preoperative measures must be strictly enforced in order to minimize the potential of complications and the surgical procedure must follow exactly as is indicated.
There were some limitations to the study, the authors pointed out. This included that this was not a comparative study and there was no control group. They conclude, however, that TPLD is a safe and effective method of treatment for removing lumbar disc herniations at the L5-S1 level.