Sex Correlation to the Prevalence of Pedal Neuromas in Various Interspaces: A Retrospective Study.

BACKGROUND: Morton's neuromas are abnormalities of the common digital nerve branch located between the lesser metatarsal heads. Historically, interdigital (Morton's) neuromas have been characterized as being most common in the third interspace and in females. The principal investigator observed Morton's neuromas commonly in the second and third interspaces in both sexes. To our knowledge, no literature exists to evaluate Morton's neuroma location with a focus on each sex independently. The present study evaluates Morton's neuroma interspace location and whether there is a variation by sex.

METHODS: In this retrospective study, 582 deidentified magnetic resonance imaging reports with a diagnosis code for Morton's neuroma were evaluated for patients scanned from January 2, 2015, through April 19, 2016. Incomplete records and those with radiologist findings inconsistent with Morton's neuroma were eliminated. For the remaining 379 patients, data were collected on sex, laterality, history of trauma, plantar plate tear, age, and interspace location. Special focus was given to second and third interspace Morton's neuromas. Data were evaluated using the Pearson χ2 and independent-samples Mann-Whitney U tests, with P < .05 indicating statistical significance.

RESULTS: No statistically significant distribution between sex and second and third interspace Morton's neuromas was noted. Right vs left foot, age, and history of trauma did not vary statistically significantly between sexes. There was a statistically significant difference between the presence of plantar plate tears between sexes. Male patients with Morton's neuromas were found to have a higher rate of plantar plate tears (P = .01).

CONCLUSIONS: This study found that there were no statistically significant differences between sexes and Morton's neuromas location, laterality, or age.