Why Is My Baby Bowlegged ?
As the legs grow and develop from birth to adulthood, they normally go through a period of being bowlegged, also known as genu varum. This period is usually from birth to 18 months, and involves both legs. If the baby stands or lies with feet together, there will be a space between the knees. This space can be measured by how many adult fingers fit between the knees. The bowlegs usually straighten out with no treatment. Orthopaedic evaluation is recommended if the bowlegs :-
- Are getting worse
- Develop after age 5 years
- Involve only one leg
- Are in combination with severe intoeing
- If the child is very short
What treatment options are available ?
Treatment depends on the age of the child and the stage of the disease. Between ages birth and two, careful observation or a trial of bracing (also called orthotics) may be done. If the child doesn't receive treatment, Blount's disease will gradually get worse with more and more bow-legged deformity. Surgery may be needed to correct the problem. For the obsese child, weight loss is helpful but often difficult.
Nonsurgical Treatment
Most of the time bowlegs or genu varum resolves on its own with time and growth. No specific treatment is needed unless the problem persists after age two. In the case of Blount's disease aggressive treatment is needed. Severe bowing before the age of three is braced with a hip-knee-ankle-foot orthosis (HKAFO) or knee-ankle-foot orthosis (KAFO). Bracing is used 23 hours a day. As the bone straightens out with bracing, the orthotic is changed every two months or so to correct the bowlegged position.
Surgery
Surgical correction may be needed especially for the younger child with advanced stages of tibia varum or the older child who has not improved with orthotics. Surgery isn't usually done on children under the age of two because at this young age, it's still difficult to sell if the child has Blount's or just excessive tibial bowing. A Tibial osteotomy is done before permanent damage occurs. Brace treatment for adolescent Blount's is not effective and requires surgery to correct the problem.
Rehabilitation
What can be expected from treatment?
Nonsurgical Rehabilitation
A Physical therapist will work with the family to teach them how to put on and take off the orthosis. Inspection and care of the skin is very important and will be included in the instruction. The child may need some help with gait training (learning how to walk properly). The therapist will help the child learn how to use any assistive diveces (e.g., walker, crutches) that may be needed.
Failure to correct the tibia vara deformity early often results in permanent damage to the growth plate and growing bone. Later, joint degeneration may occur.
After Surgery
Osteotomy with internal fixation usually heals in six to eight weeks. The cast is removed five to six weeks after the operation if there's enough bone build-up to prevent change or loss of position. A second cast is applied that keeps the knee straight but the foot and ankle free to put weight through the leg.
When the child has surgery with external fixators and distraction osteogenesis, gradual correction of the deformity takes place over the next three weeks. After the tibia is straightened extra rods are used to stabilize the external frame. The frame is taken off about 12 weeks postoperatively.
Parents or guardian should be advised that Blount's disease might not be cured with surgery. Results are usually good with infantile tibia vara. When treated at a young age and at an early stage the problem usually doesn't come back. Older patients with advanced deformity have a much higher risk of recurrence of the deformity. Patients must be followed carefully throughout their growth and development. Unilateral bowing can result in that leg being shorter than the other leg. This is called a leg length discrepancy and may need additional treatment.
