What are the other Names for this Condition? (Also known as/Synonyms)

• Aseptic Necrosis of the Tarsal Bone
• Navicular Osteochondrosis
• Osteochondritis of Tarsal/Metatarsal Bone

What is Kohler Disease? (Definition/Background Information)

• Kohler Disease is a condition that affects a bone at the arch of the foot called the tarsal navicular bone
• X-rays show that this bone is initially compressed and later breaks into pieces before healing and hardening back into bone. It occurs most frequently in children between the ages of 5 and 10 years
• Signs and symptoms of Kohler Disease include swelling, redness and/or tenderness of the affected foot which can lead to a limp or abnormal gait (style of walking)
• Although the exact underlying cause of Kohler Disease is unknown, some scientists suspect that it may be caused by excessive strain on the tarsal navicular bone and its associated blood vessels before the bone is completely ossified (hardened)
• Kohler Disease typically resolves on its own with or without treatment; however, pain relievers, rest, avoidance of weight-bearing activities, and/or casting may be recommended to help manage symptoms

(Source: Kohler Disease; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

Who gets Kohler Disease? (Age and Sex Distribution)

• Kohler Disease is a rare congenital disorder. The presentation of symptoms may occur in young children in the first decade (mostly between 5 and 10 years)
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Kohler Disease? (Predisposing Factors)

• Delayed bone formation in a child may be a risk factor for Kohler Disease

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Kohler Disease? (Etiology)

The exact underlying cause of Kohler Disease is unknown.

• However, some scientists suspect that it may be caused by excessive strain on a certain bone of the foot (tarsal navicular bone) and its associated blood vessels before the bone is completely ossified (hardened)
• Some scientists have suggested that genetic factors may play a role in the development of Kohler Disease, no disease-causing gene has been identified
• Bone ossification usually begins at age 18-24 months in girls and at age 24 to 30 months in boys
• As the child grows, their foot is required to support more weight. Ossification of the tarsal navicular bone often occurs more slowly than the other bones of the foot
• Consequently, surrounding bones may compress it and its blood vessels resulting in osteonecrosis and ischemia (a loss of blood supply)

(Source: Kohler Disease; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

What are the Signs and Symptoms of Kohler Disease?

The signs and symptoms of Kohler Disease vary, but may include:

• Swelling of the foot
• Redness of the affected area
• Tenderness, particularly along the length of the arch
• Limp or abnormal gait 

(Source: Kohler Disease; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

How is Kohler Disease Diagnosed?

Kohler Disease is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests
• Imaging studies such as X-ray of the affected foot
• Biopsy studies, if necessary

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Kohler Disease?

The complications of Kohler Disease may include:

• Worsening of symptoms such as:
• Extreme pain
• Inability to put weight on the affected foot
• Pronounced limping 
• Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Kohler Disease Treated?

Generally, Kohler’s Disease improves by itself over the course of time and treatment may not be necessary. If treatment is required, then the following may be recommended:

• Rest
• Over-the-counter pain medication
• Avoidance of weight-bearing activities
• Footwear with arch support
• Plaster walking cast

How can Kohler Disease be Prevented?

The cause of Kohler Disease is not known, and hence, no methods or guideline are presently available for its prevention.

• Severe pain and discomfort may be avoidable by resting the affected foot, allowing it time to heal
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis of Kohler Disease? (Outcomes/Resolutions)

• The prognosis of Kohler Disease is typically excellent, with symptom resolution within one year in most cases
• No lingering effects of the condition are observed once an affected child recovers from this foot disorder

Additional and Relevant Useful Information for Kohler Disease:

Kohler Disease may be known by the following additional synonyms:

• Kohler's Disease of the Tarsal Navicular
• Kohler's Osteochondrosis of the Tarsal Navicular
• Osteochondrosis of the Tarsal Bone

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/