Kohler’s Disease is a rare but self-limiting condition that affects the navicular bone in the midfoot of young children. It is characterized by temporary loss of blood supply (avascular necrosis) to the navicular, leading to bone collapse, pain, and difficulty walking. First described by Alban Köhler in 1908, this condition has an excellent prognosis, with most children recovering completely after a few months of conservative management.
How Common It Is and Who Gets It? (Epidemiology)
Kohler’s Disease primarily affects children between 2 and 7 years old, with a peak incidence at 4–5 years. It is more common in boys (approximately 5:1 male-to-female ratio), though girls can be affected, usually at a younger age due to earlier ossification of the navicular bone.
The condition is typically unilateral, but bilateral involvement occurs in less than 10% of cases. Kohler’s Disease is rare, with an estimated incidence of less than 1 in 100,000 children.
Why It Happens – Causes (Etiology and Pathophysiology)
The navicular bone is the last tarsal bone to ossify, making it vulnerable during early childhood when mechanical forces on the foot increase due to walking and running.
Proposed mechanisms include:
- Mechanical compression: As the child grows, the ossified talus and cuneiforms exert pressure on the still-soft navicular bone.
- Vascular compromise: This pressure reduces blood flow through the perichondral ring, leading to ischemia and necrosis.
- Repetitive microtrauma: Normal activities such as jumping or running may exacerbate ischemic injury.
Fortunately, the navicular’s radial blood supply enables bone revascularization and regeneration, which explains why the condition heals spontaneously over time.
How the Body Part Normally Works? (Relevant Anatomy)
The navicular bone is located in the midfoot and serves as a keystone for the medial longitudinal arch. It connects the talus (hindfoot) with the three cuneiform bones (forefoot), distributing weight and maintaining foot stability. Disruption of its vascular supply temporarily weakens the bone, leading to collapse, sclerosis, and pain during weight-bearing.
What You Might Feel – Symptoms (Clinical Presentation)
Children with Kohler’s Disease typically present with:
- Pain or tenderness over the top or inner side of the midfoot.
- Limping or refusal to bear weight on the affected foot.
- Antalgic gait, with the child walking on the outer edge of the foot to avoid pressure on the navicular.
- Mild swelling or redness over the medial midfoot (occasionally).
- No fever or systemic symptoms, which helps distinguish it from infection.
Symptoms often appear suddenly after increased activity or minor trauma.
How Doctors Find the Problem? (Diagnosis and Imaging)
Diagnosis is based on clinical findings and radiographic imaging.
- Physical examination: Reveals localized tenderness over the dorsomedial midfoot with normal ankle and subtalar motion.
- X-rays: The diagnostic hallmark. Findings include:
- Flattened or fragmented navicular bone.
- Increased density (sclerosis).
- Loss of the normal trabecular pattern.
- Collapse of the bone’s central portion.
These findings are often unilateral but may also appear on both sides.
- MRI: Rarely needed but can confirm avascular necrosis in early or atypical cases by showing bone marrow edema.
Classification
Kohler’s Disease can be staged radiographically:
- Early (Ischemic) Stage: Sclerosis and loss of trabecular pattern.
- Fragmentation Stage: Collapse and fragmentation of the navicular.
- Healing Stage: Gradual reformation and return of normal bone density.
Other Problems That Can Feel Similar (Differential Diagnosis)
- Tarsal coalition (fusion of tarsal bones causing rigid flatfoot).
- Stress fracture of the navicular or other midfoot bones.
- Osteomyelitis (infection of bone).
- Accessory navicular syndrome.
- Juvenile idiopathic arthritis.
Radiographs are key for distinguishing these conditions.
Treatment Options
Non-Surgical Care
Kohler’s Disease is self-limiting, and conservative management is almost always effective. Treatment focuses on symptom relief and preventing further stress on the bone:
- Pain control: Acetaminophen or NSAIDs such as ibuprofen.
- Footwear modification: Soft arch supports or medial heel wedges.
- Immobilization: In more severe or painful cases, a short-leg walking cast for 4–6 weeks provides excellent pain relief and speeds recovery.
- Activity modification: Avoid high-impact play or running until symptoms improve.
Surgical Care
Surgery is not indicated for Kohler’s Disease, as the condition resolves spontaneously with conservative care.
Recovery and What to Expect After Treatment
- With immobilization: Symptoms typically resolve within 6–12 weeks.
- Without immobilization: Symptoms may persist for 6–15 months but will eventually subside.
Follow-up X-rays show normalization of the navicular shape and density within 6–18 months. Children regain full function without residual deformity or arthritis.
Possible Risks or Side Effects (Complications)
- Persistent midfoot pain (rare).
- Mild flattening of the navicular bone (usually asymptomatic).
- Misdiagnosis leading to delayed treatment for other conditions (e.g., infection or fracture).
Long-Term Outlook (Prognosis)
The prognosis for Kohler’s Disease is excellent. Most children recover fully with no long-term effects. Radiographs eventually show reossification and restoration of the navicular’s normal shape and size. Unlike other avascular necroses, there is no risk of chronic deformity or arthritis.
Out-of-Pocket Costs
Medicare
CPT Code 29425 – Application of Short Leg Walking Cast: $17.92
Medicare Part B typically covers 80% of the approved cost for this procedure after your annual deductible has been met, leaving you responsible for the remaining 20%. Supplemental Insurance plans such as Medigap, AARP, or Blue Cross Blue Shield generally cover that remaining 20%, minimizing or eliminating out-of-pocket expenses for Medicare-approved services. These supplemental plans work with Medicare to fill the coverage gap and reduce your total cost.
If you have Secondary Insurance such as TRICARE, an Employer-Based Plan, or Veterans Health Administration coverage, it serves as a secondary payer. These plans often cover any remaining coinsurance or deductible, which typically ranges from $100 to $300 annually, depending on your policy and provider network.
Workers’ Compensation
If your need for a short leg walking cast is the result of a work-related injury, Workers’ Compensation will cover all associated expenses, including the cast application, follow-up care, and removal. You will not have any out-of-pocket expenses, as your employer’s insurance carrier will handle all approved charges.
No-Fault Insurance
If your injury occurred as part of an automobile accident, No-Fault Insurance will generally cover the entire cost of your cast and related care. The only potential out-of-pocket expense might be a small deductible or co-payment depending on your policy.
Example
Robert Ellis required a short leg walking cast (CPT 29425) after sustaining an ankle sprain. His estimated Medicare out-of-pocket cost was $17.92. Because Robert had supplemental insurance through AARP Medigap, his remaining balance was fully covered, leaving him with no out-of-pocket expenses for the cast application.
Frequently Asked Questions (FAQ)
Q. What is Kohler’s disease?
A. Kohler’s disease is a rare condition where a bone in the foot called the navicular bone loses its blood supply, leading to bone collapse and regeneration.
Q. Who typically gets Kohler’s disease?
A. Kohler’s disease typically affects children, most commonly boys between the ages of 3 and 7.
Q. What causes Kohler’s disease?
A. Kohler’s disease is caused by a temporary loss of blood supply to the navicular bone during its development, but the exact reason for the loss of blood supply is unknown.
Q. What are the symptoms of Kohler’s disease?
A. Symptoms include pain, swelling, tenderness over the arch of the foot, and a limp.
Q. How is Kohler’s disease diagnosed?
A. Kohler’s disease is diagnosed through a physical examination and confirmed with X-rays showing changes in the navicular bone.
Q. What does an X-ray show in Kohler’s disease?
A. X-rays typically show the navicular bone as dense, flat, and fragmented.
Q. How is Kohler’s disease treated?
A. Treatment usually includes rest, immobilization with a cast or brace, and pain management.
Q. Does Kohler’s disease require surgery?
A. Surgery is rarely needed for Kohler’s disease.
Q. How long does Kohler’s disease take to heal?
A. Healing generally occurs within several months to up to two years, and most children recover completely without long-term problems.
Q. What is the prognosis for Kohler’s disease?
A. The prognosis is excellent, and most children recover full function without any permanent deformity.
Q. Can Kohler’s disease affect both feet?
A. Yes, although it is less common, Kohler’s disease can affect both feet.
Summary and Takeaway
Kohler’s Disease is a rare, self-limiting condition that causes temporary avascular necrosis of the navicular bone in young children. It presents with midfoot pain, limp, and characteristic radiographic findings of navicular flattening and sclerosis. Conservative management with rest, immobilization, and pain control leads to full recovery in nearly all cases. Early recognition helps alleviate symptoms quickly and prevents unnecessary interventions.
Clinical Insight & Recent Findings
A 2025 case report published in the Journal of Orthopaedic Case Reports described a rare presentation of bilateral Kohler’s disease in a 5-year-old girl—the first such case reported in nearly a century.
The child presented with midfoot pain and limping after physical activity, showing radiographic signs of sclerosis and fragmentation of both navicular bones. Conservative treatment with a short-leg splint and rest led to complete recovery within a year.
The study reinforces that Kohler’s disease remains a self-limiting condition with excellent outcomes when diagnosed early and managed symptomatically, avoiding unnecessary interventions. (“Recent study on bilateral Kohler’s disease in children – see PubMed.“)
Who Performs This Treatment? (Specialists and Team Involved)
Pediatric orthopedic surgeons or pediatricians specializing in musculoskeletal conditions typically diagnose and manage Kohler’s Disease. Radiologists assist with imaging evaluation, and physical therapists may support gait rehabilitation after casting.
When to See a Specialist?
Parents should seek evaluation if their child develops unexplained midfoot pain, limping, or reluctance to bear weight—especially between ages 2 and 7.
When to Go to the Emergency Room?
Immediate evaluation is warranted if the child cannot bear weight suddenly, if there is swelling with fever (possible infection), or if the pain follows acute trauma.
What Recovery Really Looks Like?
Most children resume normal activity within 2–3 months. Occasional residual tenderness may persist briefly but resolves as the bone remodels.
What Happens If You Ignore It?
If untreated, symptoms may last longer, but the bone will eventually heal spontaneously. However, ignoring persistent pain could risk overlooking other conditions such as infection or tarsal coalition.
How to Prevent It?
There are no known preventive measures, but early recognition and rest during active symptoms minimize discomfort and ensure faster recovery.
Nutrition and Bone or Joint Health
A balanced diet rich in calcium, vitamin D, and protein supports bone growth and healing. Adequate hydration and outdoor activity (for natural vitamin D synthesis) promote healthy ossification.
Activity and Lifestyle Modifications
Encourage low-impact play and avoid excessive jumping or running during recovery. Supportive, well-fitting shoes with soft soles can prevent stress on the midfoot during healing.
Dr. Mo Athar
