Figure 1. Anteroposterior radiograph of the right foot.
Figure 2. Lateral radiograph of the right foot.
An 8-year-old is brought to the office with right foot pain that has persisted for 1 month. The pain seems to have worsened over the past week when his parents noticed him limping. The patient’s symptoms intensify with running and other athletic activities. Anteroposterior and lateral radiographs of the right foot show collapse and fragmentation of the tarsal navicular consistent with Kohler disease (Figures 1 and 2).
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Kohler disease, or osteochondrosis of the tarsal navicular, is a condition of spontaneous osteonecrosis of the navicular that occurs in pediatric patients aged 4 to 8 years during the period of ossification of the bones in the foot. The navicular is the last tarsal bone to ossify in children, and performing weight-bearing exercise is thought to disrupt the blood supply to it from compression caused by the surrounding ossified bones. Radiographs typically show collapse of the navicular with patchy areas of sclerosis and loss of the normal pattern of trabecular bone.
Kohler disease usually resolves over a short time with conservative treatment. A 4 to 6-week period of immobilization in a walking boot or cast can promote rapid revascularization and improved outcomes. The navicular reconstitutes over several weeks; therefore, athletic activities should be restricted for a few months or until complete resolution of symptoms. Pain beyond 4 to 5 months despite conservative treatment should raise suspicion of other diagnoses such as tumor or infection.1,2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor-in-chief of the Journal of Orthopedics for Physician Assistants (JOPA).
1. Cloutier, D. Image quiz: osteochondrosis of the tarsal navicular. J Bone Joint Surg. 2018;6(4):e36.
2. Krueger C. Kohler’s disease. OrthoBullets website. https://www.orthobullets.com/pediatrics/4071/kohlers-disease?expandLeftMenu=true. Updated December 7, 2016. Accessed April 24, 2019.