The impact of medial cuneiform bone variant measures on the severity of hallux valgus: A radiological study

The aetiology of hallux valgus (HV) is multifactorial in nature. The first metatarsocuneiform joint obliquity is a well-known factor in the development of the deformity. The purpose of this study is to assess the correlation of different medial cuneiform radiological measures on the severity of HV.

Full weight-bearing anteroposterior views of 152 feet with different clinical severity are divided into four groups: without deformity and with mild, moderate and severe deformities. Three medial cuneiform angles were assessed, namely, the first metatarsocuneiform angle (MCA), the first metatarsocuneiform slope angle (MCSA) and the medial cuneiform lateral tilt angle (MCLTA).

The first MCA average values of groups 1, 2, 3 and 4 were (25.16 ± 5.74°, 27.38 ± 6.14°, 30.27 ± 5.62° and 34.28 ± 6.81°), respectively. Statistical differences were detected between groups (1, 3) and (1, 4) with p values of 0.034 and 0.001, respectively. The average values of the first MCSA of groups 1, 2, 3 and 4 were 19.26 ± 4.97°, 22.54 ± 5.62°, 26.13 ± 6.36° and 32.17 ± 5.85°, respectively. Significant differences were detected between groups (1, 3) and (1, 4) with p values of 0.04 and 0.023, respectively. Average values of the MCLTA of groups 1, 2, 3 and 4 were 80.85 ± 4.49°, 74.56 ± 5.28°, 62.38 ± 6.34° and 58.78 ± 6.25°, respectively. Statistical significances were detected between groups (1, 2), (1, 3) and (1, 4) with p values of 0.026, 0.018 and 0.001, respectively.

Increasing the medial cuneiform lateral tilt increases the first metatarsocuneiform articulation obliquity demonstrated by the increase in the first MCSA which in term enhances the progression of varus deformity of the first metatarsal bone explained by the increase in the first MCA.