Complex deformity correction
What is this procedure?
After a major injury the broken bones sometimes heal in a less-than-perfect position. This can lead to deformity of the leg, for example a shortened leg (leg length discrepancy). Sometimes this does not lead to symptoms but sometimes it can be difficult to walk normally, or there can be joint pain.
Often as well as the break in the bone, there is significant damage to the skin, muscle and other soft tissues. Attempting to perform an osteotomy (cut in the bone) and plate fixation in such cases could result in inadequate correction of alignment, stretching of the nerves, wound breakdown and deep infection. In this situation, the deformity can be corrected by performing an osteotomy (cut in the bone) and using a frame to externally fix the fracture. The external fixation consists of a combination of pins going into the bone and tight wires which pass through the bone, typically attached to a series of rings around the outside of the leg. The rings are then held in position by struts running between them to make a rigid frame on the outside of the leg. If the amount of deformity is too large to correct in one go, then the struts can be adjusted to gradually correct the deformity, giving time for the nerves, muscles and other soft tissues to elongate. Often the frame will need to stay on for 4-6 months whilst the deformity is corrected gradually.
Who should consider this operation?
This operation may be of benefit if you malalignment of the lower limb and experience symptoms which are refractory to non-operative management. Good bone healing is important for this operation to be successful so if you smoke you are strongly advised to quit.
Preoperative preparation and evaluation
A full history and examination is required along with investigations to make the diagnosis and identify any other complications such as infection or nonunion (where the fracture has not healed). Full leg length, weight bearing X-rays allow the overall limb alignment to be assessed. CT or MRI scanning is a useful adjunct to physical examination if there is a rotational component to the deformity.
What happens in the post-operative period?
After surgery you will be taught how to care for your leg whilst it is in the frame, including how to keep the pin-sites (where the wires or pins enter through the skin) clean. Full weight bearing is encouraged wherever possible to stimulate bone healing. If deformity correction is to take place gradually over several months, either you or a member of your family may be required to make gradual adjustments to the frame. If this is the case, written instructions will be provided. It is very common to have some inflammation around the pin sites and sometimes a course of antibiotics is required if the skin becomes infected. When the time comes for the frame to be removed, this is usually done as a day-case procedure under general anaesthetic.