Symptomatic accessory navicular bone: A case series

IntroductionAccessory navicular bone (ANB) is present in 4-20% of the general population. It can cause of midfoot pain and consequently may lead to flat foot. The patient usually presents with pain and swelling on the medial aspect of the foot with difficulty on walking. Diagnosis is often delayed.Case reportsWe report the clinical presentation and outcome of five cases from Pakistan with symptomatic ANB comprised of four males and one female (23-45 years) that were diagnosed after a significant delay. The mean duration of symptoms was one year before final diagnosis. Three cases involved the left foot while 2 were on the right side. Flat foot (pes planus) was present in one case while 2 others had a depressed medial longitudinal arch. Overuse activities including prolonged standing and excessive walking typically precipitated onset of symptoms while the female case was also overweight. Diagnosis was clinically suspected and confirmed by radiological investigations. Three patients were diagnosed with type II ANB and two with type III. Conservative management included RICE (Rest, Ice, Compression and Elevation), non-steroidal anti-inflammatory drugs (NSAIDs), foot orthotics, activity modification, patient education, and foot care. One of the patients further used a POP boot. All cases had a good recovery and were pain free at six months follow up.ConclusionsConservative treatment is sufficient for most patients while surgical treatment is usually reserved for those with chronic persistent pain and complications. Early diagnosis and management can halt the progression of ANB to chronic pain and foot deformities.