Posterolateral spondylodesis using bioactive glass S53P4 and autogenous bone in instrumented unstable lumbar spine burst fractures. A prospective 10-year follow-up study.

BACKGROUND AND AIMS: A prospective long-term follow-up study of bioactive glass (BAG)-S53P4 and autogenous bone (AB) used as bone graft substitutes for posterolateral spondylodesis in treatment of unstable lumbar spine burst fractures during 1996-1998 was conducted. MATERIAL AND METHODS: The lumbar fractures were fixed using posterior USS instrumentation. BAG was implanted on the left side of the fusion-bed and AB on the right side. The operative outcome was evaluated on X-rays and CT scans, and a clinical examination was also performed. RESULTS: The Oswestry score was excellent, and the mean pain score 1. The mean compression rate of the injured vertebral body was 25%. A solid bony fusion was seen on CT scans on the AB side in all patients and on the BAG side in five patients, and a partial fusion in five patients, resulting in a total fusion-rate of 71% of all fused segments in the BAG group. CONCLUSIONS: Our long-term results show that BAG-S54P4 bone graft material is safe to be used as a bone graft extender in spine surgery.

Spondylodesis in the treatment of segmental instability of the lumbar spine with special reference to clinically verified instability.

We analysed the outcome of 42 consecutive patients suffering from low back pain and segmental instability of the lumbar spine who underwent spondylodesis with transpedicular fixation. There were 29 (69%) females and 13 (31%) males with a mean age of 47 +/- 9 years (range 23 to 66 years). The presence of clinically verified instability was a basic requirement for operative treatment, with at least one clinical sign of instability positive in all patients. Radiological signs of instability were detected in only 74% of the patients. After a postoperative follow-up of one year, lumbar fusion was found in 38 (90%) patients. The fusion was classified as complete in 18 (43%) and as partial in 20 (47%) patients. No fusion there was detected in 4 (10%) patients. Low back pain was completely abolished in 19 (45%) and markedly diminished in 15 (36%) patients in (17%) patients, low back pain had remained unchanged and become worse in 1 (2%) patient. Clinical signs and symptoms of instability were still detected in 10 (24%) patients. As compared to the pre-operative situation, the decrease in clinical instability was statistically significant (p = 0.02). Moreover, a significant correlation was observed between the persistence of clinically verified instability and a poor postoperative outcome in daily activities. Of all patients, 17 (40%) returned to work during the period of follow up. Based on the good outcome of our patients, the results of this study show that clinical signs and symptoms of instability can be successfully used as selection criteria for lumbar spondylodesis.