Abstract
This study developed a classification system for comminuted patella fractures based
on anatomic zones of comminution: Type 1 (proximal), Type 2 (central or stellate),
and Type 3 (distal). The system's reliability was tested by 30 graders (junior residents,
senior residents, fellows, and attendings) who assessed 60 fracture cases twice, one
month apart, for a total of 120 assessments. Interobserver reliability, measured by
Fleiss' kappa, was 0.67, showing substantial agreement, while intraobserver reliability,
measured by Cohen's kappa, was 0.82, indicating excellent agreement. Reliability was
consistent across experience levels. This novel classification system for comminuted
patella fractures demonstrated substantial interobserver and excellent intraobserver
reliability, but clinical validation is needed to confirm its practical utility.
Keywords
patella - fracture - knee - comminution - AO/OTA 34C3
