# Accessory navicular (extra foot bone) > An accessory navicular is a common extra bone along the inner edge of the foot, present from birth. It's usually harmless and painless, but it can become sore. Simple non-surgical care, such as easing activity and supportive footwear, comes first. Guide in [Children's feet](https://footanklelowerlimb.com.au/learn/topics/childrens-feet), from Foot Ankle Lower Limb: https://footanklelowerlimb.com.au/learn/accessory-navicular-syndrome Reviewed by Andrew Schox, BSc(Hons) PGradDipPod MPod (Podiatrist) on 1 November 2026. Next review by 1 November 2027. - **It's a congenital extra bone,** lying along the inside edge of the foot. - **Most people have no pain from it,** and many never know it's there. - **Simple care comes first** if it does become sore. - **A child's limp or foot pain** needs checking and isn't always this condition. ## What is an accessory navicular, and how common is it? An accessory navicular is an extra bone on the inner side of the foot, next to the navicular bone [1]. It's one of the most common extra bones in the foot, found in about 4–14% of people [1], with estimates up to 21% [2]. Most people with one have no symptoms, so it's usually found by chance [2]. Occasionally it becomes painful, which is called accessory navicular syndrome [2]. Then the inner midfoot can be tender, swollen or red [2], and the pain tends to come and go with activity [1]. If it's found by chance and doesn't hurt, it usually needs no treatment. ## What causes it, and who gets it? In children, the bump rubbing on the shoe is the most common cause of pain [3]. In adults, a twisting injury is more often the trigger [3]. Pull from the tendon and friction at the join may also play a part [4]. It often starts in the teenage years and runs in families, and genetics is thought to play a large part [1][2]. It often goes with flat feet, but which causes which isn't clear, so don't assume treating one fixes the other [2][5]. It helps to note which activities, shoes or injuries bring the pain on. ## What does it feel like, and how is it diagnosed? The usual picture is a tender bump on the inner midfoot, which can look red or swollen [2][6]. It tends to hurt with walking, sport or shoes that rub on it, and it comes and goes with activity [6][1]. It often starts in the teenage years, especially in teenagers who play sport [7][1]. A podiatrist or doctor can usually diagnose it from your history and an examination, with an X-ray to confirm [4][1]. The bump is usually easy to feel [1]. A recent injury or bruising can point to a broken bone instead, which can look similar [2][3]. A child's inner foot pain or limp shouldn't be assumed to be this condition [8]. ## What helps first? Once the pain has been checked and is thought to come from the bone, non-surgical care comes first [2][4][8][9]. - **Ease off what hurts.** Cut back on activities that bring the pain on, then build back up gradually [1]. - **Wear supportive shoes** that fit well and don't press on the bump [4]. - **Ask about arch supports.** A podiatrist can advise on arch supports or custom orthotics (shoe inserts) [2][1]. - **Use ice** [2]. - **A boot or cast** is sometimes used briefly. Follow your clinician's advice on how long [1]. Anti-inflammatory medicines (NSAIDs) call for particular care in children [2][4]. These steps aren't for a limp or foot pain with warning signs or no clear cause [8][9]. ## What helps if that isn't enough? If your pain continues despite non-surgical care, surgery to remove the extra bone or the painful part may be the next step [6][7]. A flat foot needs to be dealt with at the same time [10]. Before any operation, the planned procedure and the reasons for it, the risks, what rehabilitation involves and when you or your child can return to sport are all points that can be explained beforehand. ## How long does it take to get better, and can it come back? In growing children, the type of accessory navicular appears to change as the skeleton matures, and a Type II is likely to develop into a Type III over time [6]. Joining doesn't necessarily mean the pain has gone [6][7]. How long care takes, and whether anything stops the pain coming back, isn't clear yet, and the findings give no evidence-based answer on how long to keep using orthotics or exercises. For children with flat feet, choosing suitable, well-fitting shoes and helping them keep to a healthy weight as the arch develops are sensible general steps [11]. Return to sport gradually if the pain comes back. ## What can make it serious? - Your pain is getting worse, or doesn't settle with rest, less activity or pain relief. - You have pain at night or at rest that doesn't settle. - Your child has a limp that hasn't improved after a week, limps without pain, or doesn't want to put weight on their foot. - Your child has a fever with a limp or a painful, red, hot or swollen joint, or seems very unwell with foot or leg pain. - Your child suddenly has severe pain in one joint and is limping. - You can't put weight on your foot or take four steps after an injury. - You think you may have broken a bone in your foot or ankle in an injury, for example you heard a crack, or it swelled or bruised badly within minutes. - Your child has hurt their foot or toe and it may be broken (in children a break can look like a sprain). ## Common questions ### Is an accessory navicular dangerous? Usually not. It's a common extra bone that people are born with, and most people who have one never notice it. It only sometimes becomes sore, and simple care usually comes first. The bone itself isn't the worry. ### Can my child keep playing sport with a painful accessory navicular? The usual plan is to cut back on the activities that bring the pain on for a while, then build back up gradually. Your podiatrist or GP can advise how much sport suits your child while the foot is sore. ### Do I need an X-ray for inner foot pain? A podiatrist or doctor usually works it out from your history and an examination, and the bump is often easy to feel. An X-ray is commonly used to confirm it. ## Further reading - [Accessory navicular (extra foot bone) on Clindice](https://clindice.com/accessory-navicular-syndrome) - [Accessory navicular](https://www.kentcht.nhs.uk/leaflet/accessory-navicular/), NHS - [What Is an Accessory Navicular Bone?](https://my.clevelandclinic.org/health/body/accessory-navicular-bone), Cleveland Clinic - [Ortho-pinion - What Is an Accessory Navicular - AAOS](https://www.orthoinfo.org/diseases--conditions/ortho-pinion-accessory-navicular/), OrthoInfo (American Academy of Orthopaedic Surgeons) - [Clinical Practice Guidelines : Navicular Fractures - Emergency Department](https://www.rch.org.au/clinicalguide/guideline_index/fractures/Navicular_Fractures_-_Emergency_Department/), The Royal Children's Hospital Melbourne - [Foot pain: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/003183.htm), MedlinePlus ## Sources 1. Accessory navicular (extra foot bone) · Royal Berkshire NHS Foundation Trust. https://www.royalberkshire.nhs.uk/media/nf5pq5j5/accessory-navicular_apr25.pdf 2. The prevalence and anatomy of accessory navicular bone: a meta-analysis · Stolarz K, Osiowski A, Preinl M et al. · Surgical and Radiologic Anatomy · 2024. https://doi.org/10.1007/s00276-024-03459-x 3. Prevalence and classification of accessory navicular bone: a medical record review · Alsager GA, Alzahrani K, Alshayhan F et al. · Annals of Saudi Medicine · 2022. https://doi.org/10.5144/0256-4947.2022.327 4. Effects of customized orthoses on foot morphology and pressure in patients with accessory navicular syndrome · Pu X, Xing W, Cheng Z et al. · BMC Musculoskeletal Disorders · 2025. https://doi.org/10.1186/s12891-025-08689-7 5. Sustainable treatment success of an Os naviculare syndrome using conservative measures, infiltration therapy, and shock waves · Andresen JR, Radmer S, Puchner SE · Journal of Surgical Case Reports · 2024. https://doi.org/10.1093/jscr/rjae544 6. A retrospective study on factors predictive of operative intervention in symptomatic accessory navicular · Knapik DM, Archibald HD, Xie KK et al. · Journal of Children's Orthopaedics · 2019. https://doi.org/10.1302/1863-2548.13.180168 7. Investigation of accessory navicular in local pre-adolescence children: A longitudinal study with 2-year follow-up-KID Locomo Study · Sasaki T, Teraguchi M, Mure K et al. · PLoS One · 2025. https://doi.org/10.1371/journal.pone.0328339 8. Limping in children · NHS. https://www.nhs.uk/symptoms/limp-in-children/ 9. Atraumatic painful limb, paediatrics (1126) · NHS Greater Glasgow and Clyde. https://www.clinicalguidelines.scot.nhs.uk/ggc-paediatric-guidelines/ggc-paediatric-guidelines/emergency-medicine/atraumatic-painful-limb-paediatrics-1126/ 10. Adolescent accessory navicular · Leonard ZC, Fortin PT · Foot and Ankle Clinics · 2010. https://doi.org/10.1016/j.fcl.2010.02.004 11. Risk Factors of Flatfoot in Children: A Systematic Review and Meta-Analysis · Xu L, Gu H, Zhang Y et al. · International Journal of Environmental Research and Public Health · 2022. https://doi.org/10.3390/ijerph19148247 --- This is general information, not advice about your own situation. To discuss your issues, book with one of our podiatrists. In an emergency, call 000.