Fracture dislocations of the tarsometatarsal joints: Analysis of interrater reliability in using the modified Hardcastle classification system.

Fracture dislocations/subluxations of the tarsometatarsal joint are complex injuries that are often misdiagnosed. Prompt recognition and treatment of Lisfranc injuries decrease the likelihood of long-term sequelae. The original (1909) classification system was modified in 1982 and again in 1986. The 1986 classification system, developed by Hardcastle et al, is used most widely in clinical practice and is cited most often in the biomedical literature. For this-or any-classification system to be beneficial, however, multiple observers must be able to use it in a consistent manner, and a high level of interrater agreement should exist. This study examined interrater reliability among clinicians using the modified Hardcastle classification system for Lisfranc fracture dislocations. Thirteen Lisfranc injury radiographs were evaluated by 21 independent observers consisting of surgeons and residents (podiatric and orthopedic) as well as musculoskeletal radiologists, who classified radiographs according to the modified Hardcastle classification system. We used kappa statistics to evaluate the degree of interrater reliability for the entire group. A mean weighted kappa value of 0.54 was found for the group. Moderate interrater agreement was observed among clinicians interpreting the modified Hardcastle classification system for Lisfranc fracture dislocations.