Risk Factors of De Novo Scoliosis in the Elderly
Remzi A. Ozerdemoglu, MD**
Salim Ersozlu, MD*
Rasim Serifoglu, MD*
Cagatay Ozturk, MD*
*Dept. of Orthopedic Surgery, Uludag University, Bursa, Turkey; **Dept. of Orthopedic Surgery, S.Demirel University, Isparta, Turkey
PURPOSE: The main purpose of this study was to analyze the age related degenerative process in the lumbar spine, in order to determine potential risk factors related to the evolution of de novo scoliosis in the elderly.
METHODS: This prospective study includes 121 adults (› / = 50 years of age) evaluated by medical history, physical examination, and standing spinal roentgenograms. Cases with prior history of scoliosis, trauma or spinal surgery were excluded. Analyzed radiological parameters included: degree of listless (%), wedging (%), and height of each lumbar vertebra, wedging (%), and height of disc, length of vertebral spurs, lumbar lordosis, lumbosacral, lumbo (L5) horizontal and sacro-horizontal angles, sagittal indexes, pelvic tilt on A-P X-ray, depth of L5 from the intercrest line, also -if present- curve pattern [size, side, length, rotation, location, # of curve], and level presented with the most obvious degenerative changes [MODC]. Uni- and multi-variate statistical methods were used for analysis.
RESULTS: There were 33 male and 88 female with the mean age of 63±7 years (range, 50-93). Scoliosis (>10º Cobb angle) was found in 35 cases, with an average curvature of 15±6º (range, 11-37). Low back pain and leg pain were more common in women (Fisher's Exact Test, p=0.004, p=0.013) and in cases with scoliosis (Fisher's Exact Test, p=0.001, p=0.046). Asymmetric disc collapse and spur formation were most obvious at the L3-4 disc level, whereas, on A-P X-rays, wedging and listhesis were most frequently seen at the L3 vertebra. MODC at L2-3 and L4-5 disc levels were significant more frequent in cases with scoliosis (Mann-Whitney U test, p=0.010, p=0.011, respectively). Upon multivariate analysis lateral listhesis of L3, asymmetric collapse of L3-4 disc, and pelvic tilt on A-P X-ray were risk factors significant for the formation of scoliosis (p=0.000, p=0.000, p=0.001, respectively). If only cases with scoliosis were evaluated, MODC at the L3-4 disc level, and a more cranial apex of curve were predictive for a higher degree of scoliosis, whereas MODC at the L5-S1 level was related to lesser degree of scoliosis (multivariate regression test, p=0.009, p=0.017, p=0.009, respectively).
CONCLUSIONS: Degenerative changes in the middle lumbar region (particularly at L3-4 disc level), and pathologic conditions in the hip or lower extremities resulting in pelvic tilt, seem to be important risk factors in the evolution of degenerative adult scoliosis. Likewise, asymmetric degenerative changes at the L3-4 disc level, and a more cranial apex of curve was predictive for an increase of scoliotic curve.