Pediatric Lateral Humeral Condyle Fractures: Reliability of a Modified Jakob Classification System and its Impact on Treatment Planning With or Without Arthrography.

Abstract

Various lateral humeral condyle fracture (LHCF) classification systems have been in use since the 1950s, but limited research exists on their reliability. The most widely utilized, yet un-validated system is that of Jakob and colleagues. The purpose of the current study was to analyze the reliability of a modified Jakob classification system and its value in guiding treatment either with or without arthrography. Interrater and intrarater reliability studies were performed using radiographs and arthrograms from 32 LHCFs. Radiographs were presented to 3 pediatric orthopaedic surgeons and 6 pediatric orthopaedic surgery residents who were asked to classify the fractures according to a modified Jakob classification system, enunciate their treatment plan, and whether they would utilize arthrography. Classification was repeated within 2 weeks to assess intrarater reliability. The treatment plan using radiographs only and radiographs with arthrography were compared at both rating points. The modified Jakob system had excellent interrater reliability using only radiographs with a kappa value of 0.82 and an overall agreement of 86%. The average kappa for intrarater reliability using only radiographs was 0.88 with a range of 0.79 to 1.00 and an average overall agreement of 91% with a range of 84% to 100%. Interrater and intrarater reliability was poorer using both radiographs and arthrography. On average, arthrography changed the treatment plan in 8% of cases. The modified Jakob classification system proved to be a reliable classification system for LHCFs, independent of arthrography, given the excellent free-marginal multirater kappa values. Level III-diagnostic.