[Subtrochanteric end-to-side valgus osteotomy for severe infantile coxa vara]

Area of Science:

• Pediatric Orthopedics
• Skeletal Dysplasias
• Hip Surgery

Background:

• Infantile coxa vara, characterized by a collodiaphyseal angle of 100 degrees or less, often presents with femoral neck pseudarthrosis.
• This condition disrupts normal hip biomechanics, affecting muscle function, lever arms, and force distribution on the femoral neck.
• Accurate leg length and proper greater trochanter development are crucial for normal growth and function.

Purpose of the Study:

• To evaluate a surgical technique for correcting severe infantile coxa vara.
• To achieve healing of concurrent femoral neck pseudarthrosis.
• To restore normal hip biomechanics, including muscle length-tension relationships and lever arms.

Main Methods:

• The procedure involves preoperative planning, a lateral approach to the proximal femur, and insertion of a guide wire and cannulated chisel.
• A subtrochanteric osteotomy is performed, followed by repositioning of bone fragments and fixation with a plate and screws.
• Postoperative management includes 6-week spica casting.

Main Results:

• The study included 13 children (20 hips) with various forms of coxa vara, treated at an average age of 7.1 years.
• A 100% responder rate was observed at a mean follow-up age of 13.4 years.
• All femoral neck pseudarthroses healed, with one case of recurrent coxa vara requiring reoperation.

Conclusions:

• The described surgical technique is effective in treating severe infantile coxa vara.
• It successfully promotes healing of femoral neck pseudarthrosis and restores hip biomechanics.
• This approach offers a viable solution for complex pediatric hip deformities.