Accessory Ossicles and Navicular Bone Disorders in Foot Anatomy

The human foot exhibits a range of normal anatomical variants known as accessory ossicles, small extra bone fragments that arise from unfused secondary ossification centres. Although most ossicles remain asymptomatic, they may become implicated in pain syndromes, impingement of tendons or ligaments, degenerative changes and avascular necrosis. The accessory navicular bone is among the most frequently encountered variants and can alter medial‐longitudinal‐arch mechanics and the biomechanics of the tibialis posterior tendon. Navicular disorders encompass a spectrum from flatfoot deformity associated with a symptomatic accessory navicular to Kohler’s disease, an osteochondrosis of the navicular marked by vascular compromise. Accurate imaging interpretation using radiography, ultrasonography, computed tomography and magnetic resonance imaging is essential to distinguish accessory ossicles from fractures or other pathologies. Management ranges from conservative measures—orthotic support, physiotherapy and anti‐inflammatory medication—to minimally invasive and microsurgical approaches aimed at restoring blood flow or realigning the navicular complex. Recognition of these variants is critical to avoid misdiagnosis, guide targeted intervention and optimise functional outcomes across diverse patient populations.

Research from Nature Portfolio

Recent clinical findings have demonstrated that targeted microsurgical intervention for paediatric navicular osteonecrosis can expedite recovery and alleviate pain. In a small series of children with refractory Kohler’s disease, navicular decompression combined with micro‐circulation reconstruction led to rapid improvements in visual analogue pain scores and restoration of normal bone density within months. All patients resumed full activities by three months post‐operation, highlighting the potential of microsurgical techniques to correct vascular insufficiency in the navicular and shorten convalescence compared with prolonged conservative treatment.

Accessory Ossicles and Navicular Bone Disorders in Foot Anatomy publication trend

The graph below shows the total number of articles in accessory ossicles and navicular bone disorders in foot anatomy across all publications each year (not limited to Nature Index journals).

Technical terms

Accessory ossicle: A small, supernumerary bone arising from an unfused ossification centre, typically asymptomatic but sometimes implicated in foot pathology.

Accessory navicular bone: An ossicle adjacent to the medial aspect of the navicular, classified into three morphological types based on size and degree of fusion.

Kohler’s disease: Paediatric osteochondrosis of the navicular bone caused by avascular necrosis, presenting with midfoot pain and altered gait.

Impingement: Pathological contact between an ossicle and surrounding soft tissues or bone, leading to pain, inflammation or restricted movement.

References

1. Clinical report of microsurgical treatment of Kohler's disease. Scientific Reports (2024).
2. Accessory Ossicles of the Foot and Ankle: Disorders and a Review of the Literature. Cureus (2017).
3. Anatomical variation in the ankle and foot: from incidental finding to inductor of pathology. Part II: midfooot and forefoot. Insights into Imaging (2019).
4. Accessory Ossicles in the Region of the Foot and Ankle: An Epidemiologic Survey in a Jordanian Population. Medicina (2021).