The comprehensive anatomical spinal osteotomy and anterior column realignment classification.

Area of Science:

• Spine surgery
• Orthopedic surgery
• Surgical anatomy

Background:

• Spinal osteotomies and anterior column realignment (ACR) are crucial for restoring or preserving spine lordosis and sagittal alignment.
• Existing techniques offer varied degrees of spinal realignment, necessitating a standardized approach for clear communication and outcome assessment.

Purpose of the Study:

• To propose a comprehensive anatomical classification system for anterior column realignment (ACR) and its variants.
• To establish a common language for describing technical complexity and invasiveness in ACR procedures.
• To standardize clinical and radiographic outcomes associated with ACR utilization.

Main Methods:

• Development of a 6-grade anatomical classification for ACR, incorporating anterior longitudinal ligament (ALL) release and varying degrees of posterior column release/osteotomies.
• Inclusion of surgical approach (anterior, lateral, or posterior) as a classification parameter.
• Reliability assessment through analysis of 16 clinical cases rated twice by 14 spine surgeons, with Fleiss kappa coefficients calculated.

Main Results:

• The classification details 6 grades (A through 5) of ACR, ranging from ALL release with hyperlordotic cage to vertebral body resection.
• Intraobserver reliability was 97%, and interobserver reliability was 98% among the 14 participating spine surgeons.
• The classification demonstrated high consistency and reproducibility across a diverse group of surgeons.

Conclusions:

• The proposed anatomical classification provides a consistent and reproducible method for describing various posterior and anterior column releases and osteotomies.
• This classification system is reliable and can serve as a common language to standardize reporting of ACR procedures and outcomes in spinal surgery.