Reliability of a Modified Watson-Jones Classification for Tibial Tubercle Fractures in Children

Area of Science:

• Orthopaedic Surgery
• Pediatric Orthopaedics
• Radiology

Background:

• Pediatric tibial tubercle fractures, first described in 1852, lack systematically evaluated classification system reliability.
• Sir Watson-Jones introduced a classification in 1955, but its validation remains incomplete.

Purpose of the Study:

• To assess the intraobserver and interobserver reliability and reproducibility of a modified Watson-Jones (mWJ) classification system for pediatric tibial tubercle fractures.
• To evaluate the impact of advanced imaging (CT/MRI) on the diagnostic reliability of the mWJ classification.

Main Methods:

• Three pediatric orthopaedic surgeons and three residents classified 30 tibial tubercle fractures using the mWJ system on radiographs.
• Fractures were classified twice over two weeks, with and without advanced imaging (CT/MRI), to assess variability.

Main Results:

• Substantial intraobserver reliability was found with radiographs alone (κw = 0.733), improving with advanced imaging (κw = 0.783).
• Interobserver reliability was substantial with radiographs (κw = 0.69) and improved with advanced imaging (κw = 0.75).
• No significant difference in reliability was observed between attending surgeons and residents.

Conclusions:

• The modified Watson-Jones classification system demonstrates substantial reproducibility among surgeons for pediatric tibial tubercle fractures.
• Classification systems are vital for knowledge transfer, treatment guidance, and communication in academic literature.
• The mWJ classification is a reliable tool for assessing pediatric tibial tubercle fractures, with enhanced accuracy using advanced imaging.