[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Lower limb](https://durgical.com/en/anatomy/region/lower-limb/) › Navicular [Skeletal system](https://durgical.com/en/anatomy/system/skeletal-system/) · [Lower limb](https://durgical.com/en/anatomy/region/lower-limb/) # Navicular The navicular is a boat-shaped bone on the inner midfoot, at the top of the arch, in front of the [talus](https://durgical.com/en/anatomy/talus/). Official name: Navicular bone [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=lower_limb&select=navicular&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A boat-shaped bone on the inner side of the midfoot, between the talus and the three cuneiforms. ## What it does Acts as the keystone of the inner arch. The tibialis posterior tendon attaches to it. ## Key points - Stress fractures run in the relatively avascular central third; tenderness at the dorsal N spot is the clue - Keystone of the medial longitudinal arch: with the [spring ligament](https://durgical.com/en/anatomy/plantar-calcaneonavicular-ligament/) it forms a socket for the talar head - Tibialis posterior inserts mainly on the tuberosity; its failure causes adult-acquired flatfoot - Köhler disease: avascular necrosis in young children, more often boys, which usually resolves on its own ## Key facts **Joints with** Talus (head); three cuneiforms; sometimes cuboid **Landmarks** Navicular tuberosity (main insertion of tibialis posterior); concave posterior surface for talar head; three anterior facets for cuneiforms ## Relations **Behind** Talar head at the talonavicular joint, part of the transverse tarsal (Chopart) joint **In front** Medial, intermediate and lateral cuneiforms **Medial** Tuberosity with the [tibialis posterior tendon](https://durgical.com/en/anatomy/tendon-of-tibialis-posterior/); [abductor hallucis](https://durgical.com/en/anatomy/abductor-hallucis/) below **Lateral** [Cuboid](https://durgical.com/en/anatomy/cuboid-bone/), sometimes with a small joint; calcaneonavicular part of the [bifurcate ligament](https://durgical.com/en/anatomy/bifurcate-ligament/) **Above** Dorsal [talonavicular ligament](https://durgical.com/en/anatomy/talonavicular-ligament/); the [dorsalis pedis artery](https://durgical.com/en/anatomy/dorsalis-pedis-artery/) and [deep fibular nerve](https://durgical.com/en/anatomy/deep-fibular-nerve/) cross the dorsum of the midfoot nearby **Below** Spring (plantar calcaneonavicular) ligament and the plantar slips of [tibialis posterior](https://durgical.com/en/anatomy/tibialis-posterior-muscle/) ## How to find it The tuberosity is the bony bump on the medial border of the foot, in front of and below the medial malleolus. The N spot lies on the dorsum over the proximal navicular, just lateral to the [tibialis anterior tendon](https://durgical.com/en/anatomy/tendon-of-tibialis-anterior/). ## Examination - Feiss line: standing, the navicular tuberosity normally lies on a line from the medial malleolus to the [first metatarsal](https://durgical.com/en/anatomy/first/) head; a drop below it shows a flattened medial arch ## On imaging Stress fractures are often invisible on X-rays: CT shows the sagittal line in the central third and MRI shows early bone oedema. Standing views assess arch collapse (Meary's line from talus to first metatarsal). ## Common problems - Stress fracture: common in sprinters and jumpers. It causes vague midfoot pain and is easy to miss. - Accessory navicular: an extra small bone on the inner side that can hurt where the tendon pulls. - Rarely, the bone loses its blood supply. ## How it is diagnosed A physical exam (tenderness on top of the bone). X-rays often look normal early; CT or MRI confirm a stress fracture. ## Treatment - Stress fracture: a cast or boot with no weight on the foot for several weeks, then a gradual return to activity. - Displaced or slow-healing fractures: surgery with screws, sometimes with a bone graft from the patient or a donor. ## Clinical notes - Müller–Weiss syndrome: spontaneous collapse of the lateral navicular in adults, giving a comma shape on X-ray - The talonavicular joint is the key joint fused in triple arthrodesis, because it controls most hindfoot motion ## Anatomical variants - Accessory navicular (reported in about 4–21%, often both feet): type I a sesamoid in the tendon, type II joined by a synchondrosis (most often painful), type III fused as a horn-shaped tuberosity - Os supranaviculare on the dorsum near the talonavicular joint ## Development The last tarsal bone to ossify, around age 3; irregular or multiple centres at this stage are normal. ## Memory aid Tarsal bones from the heel forwards: "Tiger Cubs Need MILC" (Talus, [Calcaneus](https://durgical.com/en/anatomy/calcaneus/), Navicular, Medial, Intermediate and Lateral cuneiforms, Cuboid). ## Related conditions - [Clubfoot (talipes equinovarus)](https://durgical.com/en/conditions/clubfoot/) - [Flatfoot (pes planus)](https://durgical.com/en/conditions/flatfoot/) ## Test yourself Think of the answer, then tap the question to see it. ## Which tendon inserts mainly on the navicular tuberosity? The tibialis posterior tendon; its failure causes adult-acquired flatfoot. ## Where do navicular stress fractures occur and what is the clinical clue? In the relatively avascular central third; tenderness at the dorsal N spot. ## Why can a navicular stress fracture be missed on X-ray, and what confirms it? X-rays are often normal early; CT shows the fracture line and MRI shows early bone oedema. ## What is Köhler disease? Avascular necrosis of the navicular in young children, more often boys, which usually resolves on its own. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/navicular-bone/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** os naviculare TA2 1484 **Official Spanish (DeCS)** Hueso navicular DeCS D013639 **English (TA2)** Navicular bone **Also called** os naviculare pedis ## Related - [Talus](https://durgical.com/en/anatomy/talus/) - [Medial cuneiform](https://durgical.com/en/anatomy/medial-cuneiform-bone/) - [Intermediate cuneiform](https://durgical.com/en/anatomy/intermediate-cuneiform-bone/) - [Lateral cuneiform](https://durgical.com/en/anatomy/lateral-cuneiform-bone/) - [Spring ligament](https://durgical.com/en/anatomy/plantar-calcaneonavicular-ligament/) - [Bifurcate ligament](https://durgical.com/en/anatomy/bifurcate-ligament/) - [Talonavicular ligament](https://durgical.com/en/anatomy/talonavicular-ligament/) - [Top-of-foot arteries](https://durgical.com/en/anatomy/arcuate-artery/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=23476&filter=ths_termall&q=Huesos%20Tarsianos); [Anatomy, Bony Pelvis and Lower Limb: Navicular Bone](https://www.ncbi.nlm.nih.gov/books/NBK547675/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/navicular-bone/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/navicular-bone/