RT Journal Article
SR Electronic
T1 The Impact of Adult Thoracolumbar Spinal Deformities on Standing to Sitting Regional and Segmental Reciprocal Alignment
JF International Journal of Spine Surgery
JO Int J Spine Surg
FD International Society for the Advancement of Spine Surgery
SP 308
OP 316
DO 10.14444/6042
VO 13
IS 4
A1 KATHERINE E. PIERCE
A1 SAMANTHA R. HORN
A1 DEEPTEE JAIN
A1 FRANK A. SEGRETO
A1 COLE BORTZ
A1 DENNIS VASQUEZ-MONTES
A1 PETER L. ZHOU
A1 JOHN MOON
A1 LEAH STEINMETZ
A1 CHRISTOPHER G. VARLOTTA
A1 NICHOLAS J. FRANGELLA
A1 NICHOLAS STEKAS
A1 DAVID H. GE
A1 AARON HOCKLEY
A1 BASSEL G. DIEBO
A1 SHALEEN VIRA
A1 HADDY ALAS
A1 AVERY E. BROWN
A1 RENAUD LAFAGE
A1 VIRGINIE LAFAGE
A1 FRANK J. SCHWAB
A1 HEIKO KOLLER
A1 AARON J. BUCKLAND
A1 MICHAEL C. GERLING
A1 PETER G. PASSIAS
YR 2019
UL http://ijssurgery.com//content/13/4/308.abstract
AB Background: Regional and segmental changes of the lumbar spine have previously been described as patients transition from standing to sitting; however, alignment changes in the cervical and thoracic spine have yet to be investigated. So, the aim of this study was to assess cervical and thoracic regional and segmental changes in patients with thoracolumbar deformity versus a nondeformed thoracolumbar spine population. Methods: This study was a retrospective cohort study of a single center's database of full-body stereoradiographic imaging and clinical data. Patients were ≥ 18 years old with nondeformed spines (nondegenerative, nondeformity spinal pathologies) or thoracolumbar deformity (ASD: PI-LL > 10°). Patients were propensity-score matched for age and maximum hip osteoarthritis grade and were stratified by Scoliosis Research Society (SRS)–Schwab classification by PI-LL, SVA, and PT. Patients with lumbar transitional anatomy or fusions were excluded. Outcome measures included changes between standing and sitting in global alignment parameters: sagittal vertical axis (SVA), pelvic incidence minus lumbar lordosis (PI-LL), pelivc tilt (PT), thoracic kyphosis, cervical alignment, cervical SVA, C2-C7 lordosis (CL), T1 slop minus CL (TS-CL), and segmental alignment from C2 to T12. Another analysis was performed using patients with cervical and thoracic segmental measurements.Results: A total of 338 patients were included (202 nondeformity, 136 ASD). After propensity-score matching, 162 patients were included (81 nondeformity, 81 ASD). When categorized by SRS-Schwab classification, all nondeformity patients were nonpathologically grouped for PI-LL, SVA, and PT, whereas ASD patients had mix of moderately and markedly deformed modifiers. There were significant differences in pelvic and global spinal alignment changes from standing to sitting between nondeformity and ASD patients, particularly for SVA (nondeformed: 49.5 mm versus ASD: 27.4 mm; P < .001) and PI-LL (20.12° versus 13.01°, P < .001). With application of the Schwab classification system upon the cohort, PI-LL (P = .040) and SVA (P = .007) for severely classified deformity patients had significantly less positional alignment change. In an additional analysis of patients with segmental measurements from C2 to T12, nondeformity patients showed significant mobility of T2-T3 (−0.99° to −0.54°, P = .023), T6-T7 (−3.39° to −2.89°, P = .032), T7-T8 (−2.68° to −2.23°, P = .048), and T10-T11 (0.31° to 0.097°, P = .006) segments from standing to sitting. ASD patients showed mobility of the C6-C7 (1.76° to 3.45°, P < .001) and T11-T12 (0.98° to 0.54°, P = 0.014) from standing to sitting. The degree of mobility between nondeformity and ASD patients was significantly different in C6-C7 (−0.18° versus 1.69°, P = .003), T2-T3 (0.45° versus −0.27°, P = .034), and T10-T11 (0.45° versus −0.30°, P = .001) segments. With application of the Schwab modifier system upon the cohort, mobility was significant in the C6-C7 (nondeformed: 0.18° versus moderately deformed: 2.12° versus markedly deformed: 0.92°, P = .039), T2-T3 (0.45° versus −0.08° versus −0.63°, P = .020), T6-T7 (0.48° versus 0.36° versus −1.85°, P = .007), and T10-T11 (0.45° versus −0.21° versus −0.23°, P = .009) segments.Conclusions: Nondeformity patients and ASD patients have significant differences in mobility of global spinopelvic parameters as well as segmental regions in the cervical and thoracic spine between sitting and standing. This study aids in our understanding of flexibility and compensatory mechanisms in deformity patients, as well as the possible impact on unfused segments when considering deformity corrective surgery.