Incidence of Accessory Navicular Bone among the Indian Population - An Original Article

The purpose of this study was to assess the incidence of accessory navicular bone (ANB) among the Indian population.

This study consisted of 510 cases of which 1020 plain radiographs of both feet were taken (anteroposterior and lateral/oblique) belonging to the age group of 18 years and older of both genders. This study was conducted retrospectively from July 2023 to July 2024 in the Department of Orthopaedics and Radiology at a Tertiary level institute. Ethics approval number I.E.S.C./W/219/2024. The primary outcome to measure was the incidence of ANB in patients consulting the orthopedic outpatient department, and the secondary outcome measured the classification of ANB into its various subtypes and the total percentage of symptomatic ANB cases.

Out of the 1020 X-rays assessed (510 cases) and evaluated it was found that 125 cases showcased signs of ANB in them, which amounts to 24.5% of cases. The classification of ANB according to their subtypes showed that Type 2a-b and Type 1-a were the most prevalent 23 (18.4%) and 23 (18.4%), respectively. Out of the total 125 ANB cases, only 13 were symptomatic, whereas the remaining cases were asymptomatic.

In conclusion, the incidence of ANB in the Indian population was 24.5%, wherein the symptomatic incidence was 10.4%. Keeping this in mind, it is imperative to consider ANB as a differential diagnosis when treating medial-side foot pain. To our knowledge, this is the first paper of its kind that brings to light the incidence of ANB in clinical practice among the Indian population.