Establishment of an Individualized Distal Junctional Kyphosis Risk Index following the Surgical Treatment of Adult Cervical Deformities.

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Publication Date


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Spine (Phila Pa 1976)


washington; swedish; swedish neuro; swedish ortho


STUDY DESIGN: Retrospective review of a multicenter comprehensive cervical deformity (CD) database.

OBJECTIVE: To develop a novel risk index specific to each patient to aid in patient counseling and surgical planning to minimize postop DJK occurrence.

BACKGROUND: Distal junctional kyphosis(DJK) is a radiographic finding identified after patients undergo instrumented spinal fusions which can result in sagittal spinal deformity, pain and disability, and potentially neurological compromise. DJK is considered multifactorial in nature and there is a lack of consensus on the true etiology of DJK.

METHODS: CD pts with baseline(BL) and at least 1-year postoperative(1Y) radiographic follow-up were included. A patient-specific DJK score was created through use of unstandardized Beta weights of a multivariate regression model predicting DJK(end of fusion construct to the 2nd distal vertebra change in this angle by

RESULTS: 110 CD pts included(61yrs, 66.4%F, 28.8kg/m2). 31.8% of these pts developed DJK (16.1% 3M, 11.4% 6M, 62.9% 1Y). At BL, DJK pts were more frail and underwent combined approach more (both P

CONCLUSIONS: This study proposes a novel risk index of DJK development that focuses on potentially modifiable surgical factors as well as established patient-related and radiographic determinants. The reference model created demonstrated strong correlations with relevant two year outcome measures, including axial pain-related symptoms, occurrence of related reoperations, and the achievement of minimal clinically importance differences for EQ. 5D.

Clinical Institute

Neurosciences (Brain & Spine)

Clinical Institute

Orthopedics & Sports Medicine