Reliability of the Anterior Humeral Line Index Compared With the Gartland Classification for Posteriorly Hinged Supracondylar Humerus Fractures.

The Gartland classification of pediatric supracondylar humerus (SCH) fractures is commonly used but inconsistently defined regarding type 1 and type 2 (posteriorly hinged) SCH fractures. This study examined the reliability of the anterior humeral line (AHL) index compared with the Gartland classification. Fifty consecutive SCH fractures on anteroposterior and lateral elbow radiographs in pediatric patients (age range, 18 months to 15 years) were classified by 11 observers (9 attendings and 2 residents) according to the Gartland classification (types 1, 2, and 3) and the AHL index (AHL0, AHL passes anterior to the capitellum; AHL1, anterior one-third capitellum; and AHL2, middle one-third capitellum), with recommendations for treatment (cast immobilization vs surgery). Five attendings repeated the evaluation 4 to 6 weeks later. Interobserver and intraobserver reliability were scored using kappa statistics. Interobserver agreement for AHL with AHL1 and AHL2 combined (AHL1/2) was substantial (kappa=0.68) and moderate (kappa=0.55) when differentiating between AHL1 and AHL2. Anterior humeral line intraobserver reliability was almost perfect (kappa=0.83). Overall interobserver agreement on Gartland fracture type was fair (kappa=0.36), with type 2 fractures having the lowest (kappa=0.27), and with substantial (kappa=0.71) intraobserver reliability. For treatment, the interobserver agreement was fair (kappa=0.39), with substantial intraobserver reliability (kappa=0.72). Observers agreed more when using the AHL index than when using the Gartland classification. Observers differed on the degree of extension in posteriorly hinged SCH fractures that requires closed reduction. The AHL index is a more consistent method than the Gartland classification in differentiating posteriorly hinged SCH fractures and may be useful in guiding treatment. [Orthopedics. 2018; 41(4):e502-e505.].