Foot scan assessment of metatarsus adductus: A useful adjunct to Bleck’s classification

•For the first time authors introduce a new measurement to assess MA severity based on the foot scanogram to better classify MA.•This novel foot scan assessment appears to be more objective.•Distance from lateral border heel line to the lateral edge of the foot was considered as “a distance and the widest part of the ball of foot was measured as “b” distance. The a/b ratio, which represents the severity of the deformity, was calculated as the Metatarsus Adductus Severity (MAS) index.•Based on MAS index authors introduce a new classification for MA. To determine the severity of metatarsus adductus (MA) comparing with Bleck’s classification as a commonly acceptable method for assessing MA, static foot scan has been used. In this cross-sectional descriptive research study, 100 subjects were equally divided into four groups according to Bleck’s classification. The feet were scanned and MA severity (MAS) index was measured on the obtained foot scan images. The MAS index was the ratio of the transverse deviation of the forefoot from the lateral border heel line to the width of the ball of the foot. The mean of the MAS index in normal, mild, moderate, and severe MA was 0.02±0.02, 0.1±0.01, 0.159±0.03, and 0.216±0.025, respectively. The difference of MAS index between each group was significant (p