What types of limb lengthening and reconstruction surgery are possible?
There are five possible options:
- gradual limb lengthening and deformity correction
- epiphysiodesis
- hemiepiphysiodesis
-
acute deformity correction
- limb shortening.
A child may need more than one of the options above to repair their limb. Each option is explained below using the repair of a leg as an example. Limb lengthening and reconstruction is usually used to correct or lengthen a leg or foot, but it can certainly be used to correct arm or hand deformities if necessary.
Gradual lengthening and deformity correction
This surgery involves mounting an external fixator on the limb. The fixator can lengthen a short limb, correct a deformity or both.
There are two main types of external fixator:
- circular rings that go around the outside of the limb
- a rail (straight bar) along one side of the limb.
With the fixator in place, the surgeon will perform an osteotomy. This involves gently dividing the bone. The surgeon will decide where on the bone to do the osteotomy based on the type of correction your child needs.
After the surgery, your child's healthcare team will show you how to adjust the fixator for your child's needs. The fixator is adjusted at home every day so it can gradually move the two parts of the bone into their new, correct, position to lengthen the limb or straighten it.
New bone will grow in the gap between the ends of the cut bone. Over time, the bone heals enough that the fixator can be removed from the limb. This will be done during another surgery in the operating room.
How soon your child may bear weight on their operated limb depends on the type of limb lengthening and reconstruction they receive.
- If a child is fitted with a circular fixator, they are usually allowed to bear weight fully on the operated limb immediately after surgery.
- If a child is fitted with a rail-type fixator, they will usually not be allowed to bear weight on the operated limb until the consolidation (healing) stage.
Epiphysiodesis
Most bones have a special layer of cartilage at each end, called a growth plate, to allow the bone to grow. When a child reaches adulthood, the growth plate cartilage becomes bone. At this point, the bone can no longer grow.
The goal of epiphysiodesis is to slow down the growth of a bone. This is achieved by performing surgery to drill into and remove the growth plate cartilage. When the growth plate is removed from the longer leg while the child is still growing, the shorter leg can catch up over time.
Epiphysiodesis can only be used on children whose bones are still growing. The surgery has to be timed very carefully and is typically done when a child is aged between 10 and 14 years, depending on the size of their leg length discrepancy. By the time your child stops growing, their legs should be the same length.
Epiphysiodesis is an excellent choice to correct small leg length differences of up to 5 cm. It is a relatively simple operation that may be done as a day surgery (your child does not stay in hospital overnight).
After surgery, your child:
- may put full weight on the leg immediately
- will not need a cast
- will need crutches for a week or two
- can go back to full activity, including contact sports, after six weeks.
Your child will also have regular follow-up appointments and X-rays in the clinic so the surgeon can check that the operation has worked. These appointments will continue until your child stops growing. By this time, both legs should be the same length.
Hemiepiphysiodesis (guided growth)
This surgery gradually allows a deformed (crooked) bone to straighten over time as a child grows. This is done by attaching a small metal plate to one side of the growth plate at the end of the crooked bone. This temporarily slows down the growth of one side of the bone while allowing the other side to continue growing, so straightening the limb. It works in a similar way to dental braces to straighten crooked teeth.
Hemiepiphysiodesis can be done as a day surgery. Your child will not feel or see the metal plate; it will only be seen on an X-ray.
After surgery, your child:
- may put full weight on the leg immediately
- will not need a cast
- will usually need crutches for a week or two
- can go back to full activity, including sports, after two weeks.
Your child will have regular follow-up appointments and X-rays in the clinic so the surgeon can check that the crooked leg is becoming straighter over time.
It usually takes six to 12 months for most bones to straighten. Once the bone is straight, your child will have a second surgery to remove the small metal plate so that the bone does not overcorrect (curve in the other direction).
Hemiepiphysiodesis works only in a child who is still growing. Many bones will stay straight after this surgery, but some will tend to grow crooked again. If this happens, the hemiepiphysiodesis may need to be repeated when the child is older.
Not all limb deformities can be corrected with this type of surgery. Your surgeon will explain if it is a good option for your child.
Acute deformity correction
Some limb deformities can be treated with limb reconstruction surgery that fixes the problem acutely. This means that treatment is completed in a single surgery; no gradual correction is needed. When your child wakes up from the surgery, their limb is already straight.
With this type of surgery, the bone(s) that need to be corrected are divided, repositioned and then held together in the right position with metal plates, screws or rods.
After surgery, your child:
- will need to limit the weight they put on their operated leg
- will usually need to use crutches for six to 12 weeks while the bone heals
- may need to do many months of physiotherapy to achieve a full recovery.
The main benefits of an acute correction are that the straightening is done in one go and there are many ways to do it. However, not all deformities can be treated in this way. For example, this type of surgery cannot lengthen a limb to any great degree.
Your surgeon will explain all the options to you so you can decide if this is a suitable treatment for your child.
Limb shortening
As the name suggests, this surgery involves shortening the longer limb. It may be used for limb length discrepancies of between 2 cm and 5 cm. It should not be used on differences greater than 6 cm.
The surgery is an alternative to lengthening the shorter leg. It is usually only considered for people who:
- have stopped growing or are near the end of growth
- can no longer be considered for an epiphysiodesis
- do not wish to undergo limb lengthening surgery.
To perform the surgery, the surgeon removes from the longer limb a piece of bone that is equal to the difference in length between the two limbs. The shortened bone is then fixed together with a metal plate or rod.
The surgery dramatically corrects the limb length discrepancy, as a child's legs will be the same length once they wake up from surgery.
While this surgery is a good solution in certain situations, it comes with some problems. Firstly, it reduces a child's overall height. Secondly, the muscles around the shortened bone become loose and weak. This can make it difficult for a child to walk and run in the early period after surgery. It can take more than a year for the muscles to regain their original strength. For these reasons, very few patients choose limb shortening.
Your surgeon will discuss with you if this limb reconstruction surgery is a reasonable option for your child.
Return to limb reconstruction learning hub