Cervical and thoracolumbar radiological sagittal parameters in asymptomatic Indian population

Introduction: There is a dearth of normative data for radiological sagittal parameters of asymptomatic Indians. The present study aimed to address this lacuna. Materials and Methods: Sagittal radiological parameters were studied in asymptomatic volunteers: seven lumbopelvic, i.e., pelvic index (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), cranial LL (crLL), caudal LL (caLL), PI-LL; three thoracic and thoracolumbar, i.e., thoracolumbar alignment (TL), thoracic kyphosis (TK), T1 slope (TS0); five cervical, i.e., cervical sagittal vertical axis (cSVA), cervical lordosis (CL), TS-CL, C2 slope (CS), C2 T1 pelvic angle (CTPA); and lastly, five global parameters: SVA, T9 spinopelvic inclination (T9SPI), T1 spinopelvic inclination (T1SPI), T1 pelvic angle (TPA), C2 pelvic angle (CPA) were studied. Results: Volunteers (n = 125) aged 41.49±12.93 years were included. Mean PI, PT, SS, LL, crLL, caLL, PI-LL, TL, TK, TS, cSVA, CL, TS-CL, CS, CTPA, SVA, T9SPI, T1SPI, TPA, and CPA were 47.23±8.04°, 13.4±6.61°, 33.68±4.59°, −56.19±7.83°, −22.71±9.82°, −45.02±10.07°, −7.83±9.4°, 9.99±11.17°, 22±7.33°, 4.88±7.64°, 34.77±12.2 mm, −6.36±10.99°, −0.5±10.02°, 2.56±9.53°, 3.54±1.04°, −36.49±23.4 mm, −10.89±2.75°, −7.88±2.17°, 5.52±6.82°, and 10.72±6.69°, respectively. As per Roussouly’s classification, the distribution for types I, II, III, and IV was 32 (25.6%), 41 (32.8%), 45 (36%), and 7 (5.6%), respectively. LL correlated significantly with PI, SS, and TK. TS had significant correlation with CL and TS-CL. cSVA significantly correlated with CL. PI-LL significantly correlated with TS-CL. CS significantly correlated with cSVA and TS-CL. TS-CL significantly correlated with cSVA. TPA correlated significantly with PT, SVA, PI, and PI-LL. CTPA correlated significantly with CL, cSVA, TK, and TS-CL. Males had significantly different SVA (−35.3 mm), TK (22.4°), TS (6.2°), TPA (6.35°), cSVA (37.1 mm), and CTPA (3.95°) when compared with females (−58.4 mm, 17.2°, −0.15°, 0.3°, 24.95 mm, and 2.85°, respectively) (P = 0.008, 0.003, 0.002, 0.003, 0.002, and 0.0005, respectively). Conclusion: Normative data for sagittal profile in Indian volunteers, enunciated in this study, can be used to guide decisions in surgery.