Table 1 Location and reported prevalence of the sesamoid and accessory ossicles of the foot

 Hallucal

Plantar aspect of the first metatarsal head

Always present

 Lesser metatarsal

Plantar aspect of the second through fifth metatarsals

0.4 % (second);

0.2 % (third);

0.1 % (fourth)

Up to 4.3 % (fifth) [4]

 Interphalangeal joint

Plantar aspect of the interphalangeal joint of the first digit of the foot

2–13 % [4]

 Os trigonum

Posterior to the talus

7–25 % [9, 10]

 Os peroneum

At the cuboid tunnel adjacent to the calcaneocuboid joint, within the peroneus longus tendon

Up to 26 % [13, 14]

 Accessory avicular

Adjacent to the tarsal navicular, within the distal posterior tibial tendon

2–21 % [9, 15]

 Os intermetatarseum

Between the first and second metatarsal

1–13 % [9, 13]

 Os vesalianum

Proximal to the base of the fifth metatarsal, within the peroneus brevis tendon

0.1–1 % [17]

 Os supranaviculare

Above the talonavicular joint

1.0–3.5 % [4, 19, 20]

 Os supratalare

Above the neck of the talus

0.2–2.4 % [4, 19, 20]

 Os talotibiale

Anterior to the tibiotalar joint

0.5 % [19]

 Os calcaneus secundarium

Adjacent to the anterior calcaneal process

0.6–7 % [21]