Objective: To measure the reliability of Albertoni’s classification for mallet finger. Methods: We performed an evaluation using a questionnaire where there were 43 pictures of radiographs of the distal interphalangeal joint with mallet finger. All lesions were classified by Albertoni’s classification, for a total of 19 respondents (12 hand surgeons and 7 interns). It was then evaluated by the interobserver agreement using the kappa coefficient, separated by groups—(1) tendon avulsion, (2) avulsion fracture, (3) fracture of the dorsal lip, and (4) phisis injury—and subgroups (each group divided into 1 and 2). Results: Agreement was excellent for the group A (k, 0.95 [0.93-0.97]) and remained good when separated into A1 and A2; group B was reasonable (k, 0.42 [0.39-0.44]), and poor when separated into B1 and B2; in the group C, agreement was good (k, 0.72 [0.70-0.74]), but when separated into C1 and C2, it became moderate. In group D, agreement was always bad (k, 0.16 [0.14-0.19]). The general agreement was moderate, with k, 0.57 (0.56-0.58). Conclusion: Albertoni’s classification evaluated for interobserver agreement is considered a reproducible classification by the method used in the research.
