Abstract
Objective
To determine if the sesamoids migrate laterally in the feet with hallux valgus or if they only appear to move, maintaining their relationship with the other forefoot structures.
Methods
Anteroposterior radiographs of 80 patients (94 feet, all weight-bearing), from the period between 2015 and 2016, were evaluated. Forty-eight had a valgus hallux angle greater than 15° (hallux valgus group) and 46 presented a hallux valgus angle lower than 15° (control group). The distances from the firstmetatarsus head and the lateral sesamoid bone to the secondmetatarsus axis weremeasured. Subsequently, the coefficients of these distances were determined by the length of the second metatarsus to adjust it for different foot sizes.
Results
Both the absolute and the relativemeasures from the firstmetatarsus head to the second metatarsus axis were significantly different between the groups, with a positive correlationwith hallux valgus and intermetatarsal angles. However, neither the absolute nor the relative distance of the lateral sesamoid bone to the second metatarsus was different between the groups, as they did not correlate with hallux valgus or intermetatarsal angles.
Conclusion
Despite the medial deviation of the first metatarsus in hallux valgus, the sesamoid bone maintains its relationship with the second metatarsus in the transverse plane. This apparent lateral displacement may lead to misinterpretation of these radiographs. This fact is of paramount importance in the pre-, intra-, and postoperative period of patients with hallux valgus.
Keywords:
hallux valgus; metatarsal bones; radiography; statistical analysis
