Spino-pelvic alignment, balance, and functional disability in patients with low-grade degenerative lumbar spondylolisthesis

OBJECTIVE: To evaluate the relationships among spino-pelvic parameters, trunk balance and functional disability in patients with degenerative lumbar spondylolisthesis. DESIGN:  Cross-sectional study. SUBJECTS: Forty-five patients with degenerative lumbar spondylolisthesis and 32 patients without degenerative lumbar spondylolisthesis. METHODS: Spino-pelvic parameters (pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis) and pain severity were evaluated. Biodex balance tests (postural stability, limits of stability, modified clinical test of sensory interaction and balance, fall risk) and Quebec Back Pain Disability Scale (QBDS) scores were measured. RESULTS: Intergroup differences were found in age, low back pain, limits of stability, pelvic incidence, pelvic tilt and some subscales of QBDS. Correlations were found: (i) in the degenerative lumbar spondylolisthesis group: between pelvic incidence and sacral slope/pelvic tilt/lumbar lordosis/height/limits of stability; sacral slope and lumbar lordosis/height/limits of stability/modified clinical test of sensory interaction and balance (eyes closed on foam); lumbar lordosis and body mass index/QBDS/postural stability/modified clinical test of sensory interaction and balance (eyes open and eyes closed on foam); (ii) in the non-degenerative lumbar spondylolisthesis group: between pelvic incidence and pelvic tilt; pelvic tilt and sacral slope/lumbar lordosis; sacral slope and lumbar lordosis/fall risk. All spino-pelvic parameters in the degenerative lumbar spondylolisthesis group and pelvic tilt in the non-degenerative lumbar spondylolisthesis group correlated with QBDS. CONCLUSION: Pelvic tilt was the major compensating factor in both groups (patients with and without degenerative lumbar spondylolisthesis). Sacral slope and lumbar lordosis contributed to partial compensation in the degenerative lumbar spondylolisthesis group. Lumbar lordosis correlated with body mass index. Sacral slope could be an indicator of fall risk in the non-degenerative lumbar spondylolisthesis group.