Limb lengthening is a highly specialized reconstructive procedure used to gradually lengthen bone so that muscles, nerves and vessels can safely stretch along with the bone. It is performed in children and adults who have variations in their leg length because of a disease, injury, or limb deficiency. The limb lengthening procedure may be combined or staged with other bone and soft tissue procedures to achieve the optimal result. This procedure is typically performed for the lengthening of the femur (thigh bone), the tibia (lower leg bone), the humerus (upper arm bone), and metatarsals (bones in the foot). Lengthening may be performed using internal devices such as a nail, or with external devices such as a hexapod frame.
During the initial surgery, the doctor cuts the bone to create two bone segments. That cut is called an osteotomy, or corticotomy. The lengthening devices is applied to the bone. Other procedures may be performed at the same time, depending on the patient’s particular case. During the first 5-7 days after surgery, the patient recovers, and the bone is allowed to rest. After this initial phase (the latency phase), the patient/family member starts adjusting the lengthening device according to the surgeon’s instructions. This is called the distraction phase. The two ends of the bone are slowly pulled away from each other and new bone grows in the space between the cut ends. This process creates a longer bone, increasing the overall length of the limb. The surgeon will evaluate the new bone with x-rays at every post operative visit. The rate of lengthening may be changed depending on how the new bone is forming. Once the lengthening goal is achieved, adjustments stop, and the new bone hardens. This is called the consolidation phase. Once the bone has hardened completely the patient’s activity will be advanced. If an external fixator was used, that device will be removed surgically. If an internal device was used, the patient will be allowed to bear full weight on their limb, and removal will be planned for a later date.
Important considerations pre-procedure:
- Good nutrition is very important for bone healing. Your child may benefit from vitamin D and calcium supplementation. We will discuss this during your initial evaluations. Your child should also be taking an age-appropriate multivitamin.
- Optimal general health is very important, as this is a lengthy process. You should have a pediatrician established for your child who can assist with any general health concerns.
- Physical therapy combined with the prescribed home exercise program is ABSOLUTELY ESSENTIAL to the success of this surgery and treatment process. You must be able to access formal physical therapy at least twice per week during the lengthening process. If your child develops any joint contractures (reductions in range of motion) we may need to increase the number of physical therapy sessions per week.
- Your child will require frequent visits to our office. It is best to schedule this procedure during a time when you and/or members of your support network will be available to take your child to clinic for all necessary visits.
- Your child will likely be able to attend school with assistive devices (walkers and wheelchairs). We will supply notes to allow for accommodation such as increased time between classes, extra sets of books, the use of their assistive devices, elevator use, and other available modalities that will help them remain safe and engaged. If your child cannot safely attend school during this treatment, you should contact their school and inquire about a hospital homebound program.
Complications:
Lengthening and deformity correction surgery is a highly specialized treatment that has potential complications. Most are easily treatable non-operatively, but occasionally surgery is required. Complications must be addressed quickly to ensure a successful treatment outcome. It is imperative that you, your child, and your support network are prepared for the treatment process and that you communicate with our clinic if you have any questions or concerns.
- Infection
- Incision site infection, though infrequent, is always a risk of surgery. You will be educated on signs and symptoms of infection.
- If an external fixator is used, pin site infections may occur at the site of pine/wire entry into the skin. They are the most common problems associated with external fixation. You will be educated on what signs and symptoms to look out for and how to communicate with a provider at the clinic to help determine if there is an infection and what to do. Typically, a course of oral antibiotics will fully address the issue.
- Very rarely an infection can occur in the bone, usually at a pin site. We will be evaluating your child’s pin sites externally at each visit, as well as using x-rays to visualize the bone quality at the site of each pin internally to make sure the bone is healthy. If there is a concern that a pin is loose, which can cause an infection, the pin will need to be surgically replaced. If the bone becomes infected, then the pin will need to be surgically replaced and the bone infection treated with intravenous and/or oral antibiotics.
- Problems with bone growth
- The new bone may grow too slowly. In that case we may need to slow down the rate of correction/lengthening. A new schedule will be provided.
- The new bone may grow too quickly. In this case we may need to speed up the rate of correction/lengthening. A new schedule will be provided. If the bone heals completely before the correction/lengthening process is complete, then the bone will need to be surgically re-cut to allow treatment to continue.
- In the case of external fixation, fractures can occur at pin sites as the result of a fall. In this case, the fixator will need to be adjusted surgically to stabilize the fracture and allow treatment to continue.
- Joint contractures can occur during the lengthening/correction process. We carefully evaluate each patient to identify those at risk for contractures and address those issues during preparatory surgeries or at the time of the initial surgery, depending on the child’s specific case. Braces and/or stretching straps are provided to stretch muscles. Physical therapy and a home exercise program are ABSOLUTELY ESSENTIAL to maintaining muscle and joint flexibility. If you are unable to access formal physical therapy for your child for the duration of treatment, then the procedure is not advised.
