Classification of Hallucal Sesamoid Bone Correlated with Hallux Valgus Severity

Table 2

Frequency of medial HSB displace grade found in 3D CT images.

		Dislocation
		Grade 0	Grade 1	Grade 2	Grade 3
Classification	I	—	—	—	—
	II	—	—	—	1
	IIIa	10	19	12	1
	IIIb	31	36	29	2
	IV	3	2	2	—

vs. classification. Note: taking the bisection line of the long axis of the first metatarsal axis as the reference line: Grade 0: no displacement of sesamoid relative to the reference line; Grade 1: overlap of less than 50% of sesamoid to the reference line; Grade 2: overlap of greater than 50% of sesamoid to the reference line; and Grade 3: complete displacement of medial sesamoid beyond the reference line laterally.