Background: Controversy exists regarding the structural and functional causes of hallux limitus, including metatarsus primus elevatus, a long first metatarsal, first-ray hypermobility, the shape of the first metatarsal head, and the presence of hallux interphalangeus. Some articles have reported on the radiographic evaluation of these measurements in feet affected by hallux limitus, but no study has directly compared the affected and unaffected feet in patients with unilateral hallux limitus. This case-control pilot study aimed to establish whether any such differences exist.
Methods: Dorsoplantar and lateral weightbearing radiographs of both feet in 30 patients with unilateral hallux limitus were assessed for grade of disease, lateral intermetatarsal angle, metatarsal protrusion distance, plantar gapping at the first metatarsocuneiform joint, metatarsal head shape, and hallux abductus interphalangeus angle. Data analysis was performed using a statistical software program.
Results: Mean radiographic measurements for affected and unaffected feet demonstrated that metatarsus primus elevatus, a short first metatarsal, first-ray hypermobility, a flat metatarsal head shape, and hallux interphalangeus were prevalent in both feet. There was no statistically significant difference between feet for any of the radiographic parameters measured (Mann-Whitney U tests, independent-samples t tests, and Pearson χ2 tests: P > .05).
Conclusions: No significant differences exist in the presence of the structural risk factors examined between affected and unaffected feet in patients with unilateral hallux limitus. The influence of other intrinsic factors, including footedness and family history, should be investigated further.