Abstract
Purpose of the study: We report the results of a series of seven cases of non-tuberculos infectious lumbar spondylodiscitis treated by posterior instrumentation and secondary anterior curettage of the infectious focus with bone grafting. This particular osteosynthesis method produces a short monosegmentary fixation limited to the space of the infected disc.
Material and methods: The series included six men and one woman (mean age 61.7 years, age range 37–82 years). The causal germ was identified in all cases: Staphylococcus aureus in five, and in one each, Staphylococcus epidermidis and Pseudomonas aeruginosa. Levels were L1L2 in one, L2L3 in two, L3L4 in three and L5S1 in one. Predisposing factors were history of prostatic cancer in two patients, coronary heart disease in one and chronic renal failure in one. One patient had received corticosteroid injections and two had no recognized co-morbid conditions. The surgical procedure was undertaken due to persistent pain in three patients (one with quadriceps amyotrophy and weakness), spinal instability with risk of neurological injury in two, and after failure of medical treatment in two patients who had persistent abscesses.
Results: Excepting one patient who died from renal failure four months after the surgical procedure, mean follow-up was 31.5 months (range six months to six years). Outcome was excellent in four patients, good in one, and a failure in one patient who was operated on because of instability. Failure of the instrumentation required surgical revision to extend the initial assembly. At last follow-up, all patients had achieved fusion of the instrumented zone and were considered to be cured of their infection.
Discussion: Classically, it is advisable to avoid instrumenting close to an infectious area in order to avoid the vicious circle of infection. Configurations described in the literature are usually extensive, blocking healthy levels beyond the infected area and compromising spinal mobility. However, a short instrumentation limited to one segment can be proposed when the end plates at the outer limits of the infectious focus are theoretically healthy. Careful analysis of the imaging data is required to carefully select patients who can benefit from this short configuration. Magnetic resonance imaging is most helpful.
Correspondence should be addressed to SOFCOT, 56 rue Boissonade, 75014 Paris, France.