Survival Rates and Risk Factors for Cephalad and L5-S1 Adjacent Segment Degeneration after L5 Floating Lumbar Fusion : A Minimum 2-Year Follow-Up.
10.3340/jkns.2015.57.2.108
- Author:
Young Seok LEE
1
;
Young Baeg KIM
;
Seung Won PARK
Author Information
1. Department of Neurosurgery, Chung-Ang University College of Medicine, Seoul, Korea. ybkim1218@cau.ac.kr
- Publication Type:Original Article
- Keywords:
Radiological adjacent segment degeneration;
Clinical adjacent segment degeneration;
Cephalad segment;
L5-S1 segment
- MeSH:
Follow-Up Studies*;
Humans;
Incidence;
Intervertebral Disc Degeneration;
Proportional Hazards Models;
Risk Factors*;
Spinal Stenosis;
Spine;
Survival Rate*
- From:Journal of Korean Neurosurgical Society
2015;57(2):108-113
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: Although the L5-S1 has distinct structural features in comparison with other lumbar spine segments, not much is known about adjacent segment degeneration (ASD) at the L5-S1 segment. The aim of study was to compare the incidence and character of ASD of the cephalad and L5-S1 segments after L5 floating lumbar fusion. METHODS: From 2005 to 2010, 115 patients who underwent L5 floating lumber fusion were investigated. The mean follow-up period was 46.1 months. The incidence of radiological and clinical ASD of the cephalad and the L5-S1 segments was compared using survival analysis. Risk factors affecting ASD were analyzed using a log rank test and the Cox proportional hazard model. RESULTS: Radiological ASD of the L5-S1 segment had a statistically significant higher survival rate than that of the cephalad segment (p=0.001). However, clinical ASD of the L5-S1 segment was significantly lower survival rates than that of the cephalad segment (p=0.038). Risk factor analysis showed that disc degeneration of the cephalad segment and preoperative spinal stenosis of the L5-S1 segment were risk factors. CONCLUSION: In L5 floating fusion, radiological ASD was more common in the cephalad segment and clinical ASD was more common in the L5-S1 segment. At the L5-S1 segment, the degree of spinal stenosis appears to be the most influential risk factor in ASD incidences, unlike the cephalad segment.
