Description and Reliability of the AOSpine Sacral Classification System.

Area of Science:

• Orthopedic Surgery
• Trauma Surgery
• Spine Surgery

Background:

• Existing sacral fracture classification systems lack validation and standardization.
• Current systems are descriptive, not uniformly applied, and lack treatment algorithms.
• A need exists for a reliable classification system for sacral fractures.

Purpose of the Study:

• To assess the reliability of the AOSpine Sacral Classification System.
• To evaluate its consistency among international spine and trauma surgeons.
• To determine its utility in standardizing sacral fracture assessment.

Main Methods:

• 18 international surgeons evaluated 38 sacral fractures.
• Assessments were repeated after 4 weeks to measure intrarater reproducibility.
• Interrater agreement was analyzed using kappa statistics for fracture severity and subtypes.

Main Results:

• Excellent intrarater reproducibility (κ=0.83) for fracture severity and substantial (κ=0.71) for subtypes.
• Substantial interrater agreement (κ=0.75) for fracture severity, highest for type-A (κ=0.95).
• Moderate interrater agreement (κ=0.58) for fracture subtypes, highest for A2 (κ=0.81).

Conclusions:

• The AOSpine Sacral Classification System shows substantial to excellent reliability among expert surgeons.
• The system demonstrates good intrarater reproducibility and moderate to substantial interrater agreement.
• This classification system is a reliable tool for sacral injuries, promoting standardized treatment.