RT Journal Article
SR Electronic
T1 Full-Body Radiographic Analysis of Postoperative Deviations From Age-Adjusted Alignment Goals in Adult Spinal Deformity Correction and Related Compensatory Recruitment
JF International Journal of Spine Surgery
JO Int J Spine Surg
FD International Society for the Advancement of Spine Surgery
SP 205
OP 214
DO 10.14444/6028
VO 13
IS 2
A1 PETER G. PASSIAS
A1 CYRUS M. JALAI
A1 BASSEL G. DIEBO
A1 DANA L. CRUZ
A1 GREGORY W. POORMAN
A1 AARON J. BUCKLAND
A1 LOUIS M. DAY
A1 SAMANTHA R. HORN
A1 BARTHÉLEMY LIABAUD
A1 RENAUD LAFAGE
A1 ALEXANDRA SOROCEANU
A1 JOSEPH F. BAKER
A1 SHEARWOOD MCCLELLAND III
A1 JONATHAN H. OREN
A1 THOMAS J. ERRICO
A1 FRANK J. SCHWAB
A1 VIRGINIE LAFAGE
YR 2019
UL http://ijssurgery.com//content/13/2/205.abstract
AB Background: Full-body stereographs for adult spinal deformity (ASD) have enhanced global deformity and lower-limb compensation associations. The advent of age-adjusted goals for classic ASD parameters (sagittal vertical axis, pelvic tilt, spino-pelvic mismatch [PI-LL]) has enabled individualized evaluation of successful versus failed realignment, though these remain to be radiographically assessed postoperatively. This study analyzes pre- and postoperative sagittal alignment to quantify patient-specific correction against age-adjusted goals, and presents differences in compensation in patients whose postoperative profile deviates from targets.Methods: Single-center retrospective review of ASD patients ≥ 18 years with biplanar full-body stereographic x-rays. Inclusion: ≥ 4 levels fused, complete baseline and early (≤ 6-month) follow-up imaging. Correction groups generated at postoperative visit for actual alignment compared to age-adjusted ideal values for pelvic tilt, PI-LL, and sagittal vertical axis derived from clinically relevant formulas. Patients that matched exact ± 10-year threshold for age-adjusted targets were compared to unmatched cases (undercorrected or overcorrected). Comparison of spinal alignment and compensatory mechanisms (thoracic kyphosis, hip extension, knee flexion, ankle flexion, pelvic shift) across correction groups were performed with ANOVA and paired t tests.Results: The sagittal vertical axis, pelvic tilt, and PI-LL of 122 patients improved at early postoperative visits (P < .001). Of lower-extremity parameters, knee flexion and pelvic shift improved (P < .001), but hip extension and ankle flexion were similar (P > .170); global sagittal angle decreased overall, reflecting global postoperative correction (8.3° versus 4.4°, P < .001). Rates of undercorrection to age-adjusted targets for each spino-pelvic parameter were 30.3% (sagittal vertical axis), 41.0% (pelvic tilt), and 43.6% (PI-LL). Compared to matched/overcorrections, undercorrections recruited increased posterior pelvic shift to compensate (P < .001); knee flexion was recruited in undercorrections for sagittal vertical axis and pelvic tilt; thoracic hypokyphosis was observed in PI-LL undercorrections. All undercorrected groups displayed consequentially larger global sagittal angle (P < .001).Conclusions: Global alignment cohort improvements were observed, and when comparing actual to age-adjusted alignment, undercorrections recruited pelvic and lower-limb flexion to compensate.Level of Evidence: 3