Predictive model for distal junctional kyphosis after cervical deformity surgery

Area of Science:

• Spine surgery
• Orthopedic surgery
• Neurosurgery

Background:

• Distal junctional kyphosis (DJK) is a significant complication following cervical deformity correction.
• Identifying patients at higher risk is crucial for improving surgical outcomes and patient selection.

Purpose of the Study:

• To develop a predictive risk index for the incidence of DJK within the first year after cervical deformity surgery.
• To identify key factors contributing to DJK development.

Main Methods:

• Retrospective review of a prospective, multicenter cervical deformity database.
• Conditional Inference Decision Trees used to identify predictive factors and cut-off points for DJK.
• Analysis of 101 surgical patients with cervical deformities.

Main Results:

• Radiographic DJK incidence was 23.8% within two years post-surgery.
• Predictive factors for DJK include preoperative malalignments (e.g., C2-T1 tilt, kyphosis, lordosis, T1 slope-cervical lordosis, SVA, C4 tilt) and surgical approaches (combined, Smith-Petersen osteotomy).
• Neurologic symptoms were associated with increased DJK risk (OR: 3.71).

Conclusions:

• Preoperative radiographic malalignments and specific surgical techniques are significant predictors of DJK.
• The identified factors can guide future strategies to minimize DJK incidence.
• Understanding these predictors aids in optimizing patient care for cervical deformity.