Incidence of Acute, Progressive, and Delayed Proximal Junctional Kyphosis Over an 8-Year Period in Adult Spinal Deformity Patients.
Oper Neurosurg (Hagerstown)
BACKGROUND: Proximal junctional kyphosis (PJK) is a common radiographic complication of adult spinal deformity (ASD) corrective surgery. Although previous literature has reported a 5 to 61% incidence of PJK, these studies are limited by small sample sizes and short-term follow-up.
OBJECTIVE: To assess the incidence of PJK utilizing a high-powered ASD database.
METHODS: Retrospective review of a prospective multicenter ASD database. Operative ASD patients > 18 yr old from 2009 to 2017 were included. PJK was defined as ≥ 10° for the sagittal Cobb angle between the inferior upper instrumented vertebra (UIV) endplate and the superior endplate of the UIV + 2. Chi-square analysis and post hoc testing assessed annual and overall incidence of acute (6-wk follow-up [f/u]), progressive (increase in degree of PJK from 6 wk to 1 yr), and delayed (1-yr, 2-yr, and 3-yr f/u) PJK development.
RESULTS: A total of 1005 patients were included (age: 59.3; 73.5% F; body mass index: 27.99). Overall PJK incidence was 69.4%. Overall incidence of acute PJK was 48.0%. Annual incidence of acute PJK has decreased from 53.7% in 2012 to 31.6% in 2017 (P = .038). Overall incidence of progressive PJK was 35.0%, with stable rates observed from 2009 to 2016 (P = .297). Overall incidence of 1-yr-delayed PJK was 9.3%. Annual incidence of 1-yr-delayed PJK has decreased from 9.2% in 2009 to 3.2% in 2016 (P < .001). Overall incidence of 2-yr-delayed PJK development was 4.3%. Annual incidence of 2-yr-delayed PJK has decreased from 7.3% in 2009 to 0.9% in 2015 (P < .05). Overall incidence of 3-yr-delayed PJK was 1.8%, with stable rates observed from 2009 to 2014 (P = .594).
CONCLUSION: Although progressive PJK has remained a challenge for physicians over time, significantly lower incidences of acute and delayed PJK in recent years may indicate improving operative decision-making and management strategies.
Orthopedics & Sports Medicine
Neurosciences (Brain & Spine)
Segreto, Frank A; Passias, Peter G; Lafage, Renaud; Lafage, Virginie; Smith, Justin S; Line, Breton G; Mundis, Gregory M; Bortz, Cole A; Stekas, Nicholas D; Horn, Samantha R; Diebo, Bassel G; Brown, Avery E; Ihejirika, Yael; Nunley, Pierce D; Daniels, Alan H; Gupta, Munish C; Gum, Jeffrey L; Hamilton, D Kojo; Klineberg, Eric O; Burton, Douglas C; Hart, Robert A; Schwab, Frank J; Bess, Shay; Shaffrey, Christopher I; and Ames, Christopher P, "Incidence of Acute, Progressive, and Delayed Proximal Junctional Kyphosis Over an 8-Year Period in Adult Spinal Deformity Patients." (2019). Articles, Abstracts, and Reports. 1791.