In an Opening Wedge Osteotomy, the surgeon cuts though the tibia on the medial side and opens a wedge. A bone graft strut is put into the wedge to hold the wedge open.
This surgery involves making an incision on the medial (inner) side of the knee. Again, care is taken to protect the nerves and blood vessels that travel across the knee joint.
Once the tibia bone is exposed, a cut is made through the upper tibia. Under the guidance of x-ray-control or image intensifier.
After the bone is cut, the two sides of the tibia are separated to form a wedge-shaped opening. This opening is then filled with bone graft. The bone graft is usually taken from iliac crest, through an incision in the side of your hip. The bone graft is held in position with a metal plate or pins. After fixing the two edges of bone with a plate or pins, the surgeon stitches the soft tissue and the skin. The leg is placed in a padded splint to protect the knee joint.
» Advantages :
» Fibular osteotomy is not necessary
» Limb is not shortened
» Patella instability is avoided
» Disadvantages :
» Bone grafts may be taken from the same side iliac crest, hence morbidity.
» Weight bearing may be delayed
» Union at osteotomy site may be delayed