Preoperative Thoracic Compensation is Associated With a Lower Risk of Proximal Junctional Kyphosis After Lower Thoracic Fusion for Adult Spinal Deformity

AI Summary

Preoperative thoracic compensation associated with lower PJK risk after lower thoracic fusion; adjusted odds ratio 0.431 (95% CI 0.261–0.713).
Patients with TC showed greater reciprocal TK increase (19.1° vs 11.0°) and lower postoperative TK (21.5° vs 33.7°) yet reduced PJK.
Absence of TC combined with lordosis overcorrection markedly increased PJK risk; odds ratio 3.41 (95% CI 1.37–8.46).

TL;DR (AI Generated)

TC remained associated with a lower risk of PJK after adjustment (odds ratio 0.431, 95% CI 0.261-0.713, P = 0.001), consistently across eight prespecified subgroups.

Relative to TC without overcorrection, the odds ratio reached 3.41 (95% CI 1.37-8.46) when TC was absent and the L1PA offset indicated overcorrection.ConclusionsTC assessed against the deformity burden was associated with a lower risk of PJK despite a larger reciprocal increase in TK.

Basic summary

Global Spine J. 2026 Oct 10:21925682261496815. doi: 10.1177/21925682261496815. Online ahead of print.

ABSTRACT

Study DesignRetrospective cohort study.ObjectivesTo determine whether thoracic compensation (TC) assessed against the deformity burden is associated with proximal junctional kyphosis (PJK) after lower thoracic fusion for adult spinal deformity (ASD).MethodsWe reviewed 343 patients fused from T9-L1 to the sacrum or pelvis with a pelvic incidence (PI) minus lumbar lordosis (LL) mismatch above 20°. Expected thoracic kyphosis (TK) was derived from the PI-LL mismatch using published equations, and a measured TK below it defined TC. PJK was defined as a proximal junctional angle of 20° or more, or revision, within two years. Multivariable logistic regression adjusted for patient, operative, and radiographic covariates including two measures of correction adequacy.ResultsPJK occurred in 60 of 124 patients (48.4%) without TC and 68 of 219 (31.1%) with TC (P = 0.002). Correction was equivalent for PI-LL, the L1 pelvic angle (L1PA), and pelvic tilt, yet the TC present group restored more TK (19.1° vs. 11.0°) while reaching a lower postoperative value (21.5° vs. 33.7°, both P < 0.001). TC remained associated with a lower risk of PJK after adjustment (odds ratio 0.431, 95% CI 0.261-0.713, P = 0.001), consistently across eight prespecified subgroups. Relative to TC without overcorrection, the odds ratio reached 3.41 (95% CI 1.37-8.46) when TC was absent and the L1PA offset indicated overcorrection.ConclusionsTC assessed against the deformity burden was associated with a lower risk of PJK despite a larger reciprocal increase in TK. Risk was highest when TC was absent and lordosis overcorrected.

PMID:42858085 | DOI:10.1177/21925682261496815

Document this CPD