LLRS Key Surgical Technique: Epiphysiodesis

Jill C. Flanagan, M.D.

An epiphysiodesis is a surgical procedure that surgically stops the growth at a specific part of the limb of a growing child through an area known as the physis, also know as the “growth plate”.

There are multiple different methods in which to perform the procedure, and you can discuss with your surgeon the technique that he or she utilizes.

In general, most surgeons employ a minimally invasive technique with 1 or 2 small incisions. This typically translates into less pain, and an earlier recovery. More information about the procedure will be discussed below.

Anatomy

The middle of a bone is known as the diaphysis, while the top and bottom are called the epiphysis. Between the epiphysis and diaphysis is the metaphysis. “Meta” is latin for change, so the “metaphysis” represents the transition from the wider epiphysis to the narrower diaphysis.

Growing children also have a physis, or “growth plate”. Long bones such as femurs, tibias, humerii, etc, have physes on either end. Shorter bones such as fingers and toes, only have a physis on one end. The physis is reponsible for the longitudinal growth of the long bones. Any damage to the growth plates may cause shortening or deformity of the affected bone.

Indications for Surgery

Epiphysiodesis is a surgical technique used in the management of growing children with limb length differences. This technique may be recommended for a growing child who has a projected limb length difference at skeletal maturity of 2-5 cm (approximately 1-2 inches).

Prior to surgery, your surgeon will estimate growth remaining of both limbs, and may check your child’s bone age (which generally requires an xray of the hand). With this information, your surgeon can calculate the final projected difference in limb length as well as the best age in which to perform your child’s surgery. Your physician will discuss the impact of this procedure on your child height at skeletal maturity.

Case example:

Your 10 year-old son has a current limb length difference of 2 cm (slightly greater than ¾” with the right limb longer. The difference is due to a condition known as hemihypertrophy. Your surgeon predicts that when your son is fully grown, he will have a 1” difference in limb lengths (2.5 cm). Based on this data, your surgeon may recommend an epiphysiodesis. In terms of when to perform the surgery, your surgeon will calculate the age at which your son will have 1” of growth remaining in the longer right side. Your surgeon would then perform the epiphysiodesis of the longer right side, allow the shorter left side to grow, and hopefully, when your son is fully grown, he has equal limb lengths. For a male with a projected difference of 1”, the surgery would likely be done around the age of 13-14 years old.

Performing an Epiphysiodesis:

There are various methods of performing an epiphysiodesis surgery, with the overall outcome the same – stopping growth of the physis. Most commonly, your surgeon will either drill the growth plate, place screws or plates across the growth plate, or do some combination.

Getting ready for surgery:

If your child is relatively healthy, and no other major procedures are also being done, then this procedure is typically outpatient. This means your child will not need to stay overnight at the hospital.

Be sure to inform your orthopaedic surgeon of any medications or supplements that you child takes. You may need to stop taking some of these before surgery. Please also inform your orthopaedic surgeon of prior surgeries, injuries, infections, and any family history of abnormal bleeding or clotting disorders.

The hospital or surgery center will contact you ahead of time to provide specific details of your procedure. Make sure to follow the instructions on when to arrive and especially on when to stop eating or drinking prior to your procedure.

Surgical Procedure:

Drilling: Typically, a small incision is made on the outer portion (lateral) of the limb, and the growth plate is carefully drilled with radiographic guidance. Your surgeon may make a second incision on the inside (medial) part of the limb and drill from this side as well.

Screw placement: Generally, two small incisions are made on each side of the limb and screws are inserted under x-ray guidance

Plate placement: Two medium sized incisions are made on each side of the limb to place a small plate with two screws spanning the growth plate.

Closure:

After your surgeon closes the skin, it is typically protected using soft dressings. Sometimes a knee brace is used. Most of the time, the surgery takes less than an hour to perform. After the procedure, your child wakes up in a recovery room, and then is brought back to you as soon as possible. Once your child is awake and has tolerated a small amount of food and drink, he/she should be able to go home on the day of surgery.

Your child should go home with a pair of crutches. He/she is allowed to walk on the operative leg, but it may be sore for a few days, and crutches can be helpful until the pain and swelling subsides. If you or your child have any questions about bearing weight, call your surgeon.

Complications:

The complication rate after epiphysiodesis surgery is very low. If complications occur, they are usually minor and are treated easily. Possible complications could include:

• Infection
• Bleeding
• Temporary Knee stiffness
• Incomplete correction of limb lengths (this will be discussed more in the next section)
• Incomplete closure of growth area (this will be discussed more in the next section)

Follow Up:

Your doctor will want to see your child back in the office 1-3 weeks after surgery to check on the incision and to make sure that your child can bend and straighten the knee well. You will also need to see your doctor prior to being cleared for sports activities and PE. Physical therapy is rarely needed unless your child is having a hard time moving the knee. After the initial visit, your surgeon will likely schedule follow ups once or twice a year until your child has completed growth to ensure that the limb lengths are more equal by the end of growth.

Outcome:

In general, epiphysiodesis surgery is relatively well tolerated, especially the more minimally invasive and instrumented techniques. The biggest “risk” with the surgery is incomplete correction or overcorrection of limb lengths. Most of the time, correction is within ½” which for most people is well tolerated.

In uncommon circumstances (<7%), the physis may not stop growing, and/or it may only partially stop growing. There are treatments available to remedy these problems, and this should be discussed more thoroughly with your surgeon.