Source: CNS 2004 San Francisco, California

Abstract:
Access to L4/L5 & L5/S1 true central disc herniations is very limited. In conventional open surgery (including microscopic approaches), important bone and soft tissue removal must occur in order to access the pathology, more so than in other locations. This, in turn, increases the likelihood of long-term spinal instability and post-surgical failed back syndrome.

The use of a small working channel scope with a double access approach is another way to treat this pathology. This approach allows precise, focused treatment, with no bone or soft tissue removal and minimal invasiveness. Pre-operative CT mapping, including full thickness "wide views" is essential.

A retrospective analysis of the years 2002 and 2003 was performed by one of the authors and the results were reported utilizing the MacNab criteria. The study population included 33 patients (66% single level), 29% females and 71% males with an age range between 13 and 83 years (mean = 36 years). There were 19 L4/L5 and 14 L5/S1 herniations. 78.78% of the herniations were contained and 21.21% uncontained. The mean follow-up time was 2.5 months (1-8).

No limitations to the double access were found in the wide view CT scans. The analysis showed the following results: Excellent: 33.33% (n = 11), Good: 57.57% (n = 19), Fair: 6.06% (n = 2) and Poor: 3.03% (n = 1). The overall success rate was 90.90%. No complications were reported. There was a statistically significant difference between the success rates of herniations at L4/5 (94.72%) and L5/S1 (85.71%) and also between uncontained (100%) vs. contained (87.56%) herniations.

Small endoscopic double access of L4/L5 & L5/S1 central herniations is not just a viable alternative to open surgery but has proven to be highly successful, avoiding the deleterious long-term effects of considerable bone removal and soft tissue resection and retraction. This minimally invasive technique is also extremely safe.