Blount's disease is relatively rare, with an estimated prevalence of less than 1% of children worldwide and a higher prevalence in certain populations. The infantile form typically presents between the ages of 1 and 3 years, while the adolescent form appears later, between 8 and 15 years. The condition is more common in African-American children and those who are overweight or obese. It affects males more often than females, and bilateral involvement (affecting both legs) occurs in about 50% of cases.

The exact cause of Blount’s disease is unknown, but certain factors are associated with a higher risk of developing the disease. For example, excessive stress on the growth plate of the tibia, particularly in children who are overweight or have early walking, is thought to disrupt normal bone development. In the adolescent form, increased body weight and rapid growth during puberty can exacerbate the deformity. Family history and genetic predisposition may also play a role.

The hallmark symptom of Blount’s disease is progressive bowing of the lower leg, typically below the knee. Other common symptoms include:

• Limb Discrepancy: One leg may be shorter than the other.

• Knee Pain: Particularly in older children or adolescents, pain in the knee may develop due to the abnormal alignment.

• Gait Abnormalities: Walking difficulties, such as limping or an altered gait, often result from the leg deformity.

• Visible Deformity: The bowing of the legs becomes more pronounced over time and may be more noticeable during walking or standing.

Blount’s disease is usually diagnosed through clinical evaluation and imaging studies. A healthcare provider will assess the patient’s medical history, physical appearance of the legs, and any related symptoms. Early diagnosis is important to prevent the condition from worsening.

• X-rays: X-rays of the lower leg are the primary diagnostic tool for Blount’s disease. They help visualize the bowing and assess the growth plates of the tibia.

• MRI or CT Scans: These imaging studies may be used in more severe cases to assess the growth plate's structure and rule out other conditions.

• Physical Examination: A physical examination will evaluate the degree of leg bowing, knee stability, and any limb length discrepancies.

The treatment of Blount’s disease depends on the severity of the condition and the age of the patient:

• Bracing: For children with the infantile form, leg bracing may be effective in early stages to correct the deformity and prevent further progression.

• Surgical Intervention: In more severe cases or when bracing is ineffective, surgery is required to correct the deformity. Procedures include osteotomy (cutting and realigning the tibia) or guided growth surgery using plates or screws to straighten the leg over time.

• Weight Management: For overweight children, weight reduction may help reduce stress on the tibia and improve outcomes.

With early detection and proper treatment, the prognosis for Blount’s disease is generally good. Bracing or surgery can effectively correct the deformity, allowing for normal leg development and function. However, if left untreated, Blount’s disease can lead to severe leg deformity, pain, and long-term mobility issues. In some cases, residual deformities may persist, especially in older children or adolescents who have more severe forms of the disease at diagnosis.

1. Gordon, J. E., & Schoenecker, P. L. (2009). "Bowlegs and Blount disease." Journal of the American Academy of Orthopaedic Surgeons, 17(7), 464-474.

2. Sabharwal, S., & Zhao, C. (2009). "The role of obesity and tibial slope in the pathogenesis of Blount disease." Journal of Pediatric Orthopedics, 29(7), 703-710.

3. Bowen, J. R., & Devito, D. P. (1984). "Treatment of adolescent Blount disease by osteotomy." The Journal of Bone and Joint Surgery, 66(5), 731-738.

4. Campos, A., & Abdelgaid, S. (2011). "Infantile tibia vara (Blount’s disease)." Orthopedic Clinics of North America, 42(4), 517-531.

5. Dobbs, M. B., & Gordon, J. E. (2017). "Blount disease." Pediatrics in Review, 38(7), 338-347.

6. https://my.clevelandclinic.org/health/diseases/22424-blounts-disease 

7. https://medlineplus.gov/ency/article/001584.htm