Inter- and intraobserver reliability of the first metatarsal sagittal alignment measurements

Abstract

Objective: First, analyze the inter- and intraobserver reliability of the angular measurements used to evaluate the first metatarsal sagittal alignment. Second, evaluate whether the anatomical type of foot interferes with the reliability of the measurements. Methods: The angular measurements used were all those found in the literature, such as first metatarsal declination angle (MDA), first distal metatarsal articular angle (DMAA), first proximal metatarsal articular angle (PMAA), lateral intermetatarsal angle (LIMA), and the angle described by Day. To evaluate interobserver reliability, the Intraclass Correlation Coefficient (ICC) was used; to evaluate intraobserver reliability, the Lin Correlation Coefficient of Agreement (LCCC) was used. Results: Among all the measurements obtained, the MDA presented the highest ICC and LCCC values in the 40 radiographs evaluated, regardless of the anatomical type of foot. Conclusion: The first MDA represents an adequate radiographic tool for measuring the first metatarsal sagittal alignment when evaluated by the CCI and LCCC. Level of Evidence IV; Therapeutic Studies; Case Series.