What is Limb Lengthening?
Limb lengthening is a reconstructive procedure where the deformed bone is straightened or missing bone is replaced. It is performed in children and adults who have variations in their leg length because of a disease, injury or birth defect. The limb lengthening procedure can be performed by minimally invasive techniques.
Indications for Limb Lengthening
Conditions that can be corrected by a limb lengthening procedure include:
- Broken bones resulting in a shortened limb
- Bone infections resulting in leg length variations
- Growth disturbances resulting in a limb length discrepancy
Principle Behind Leg Lengthening
The process of increasing the bone length depends on tissue and bone regeneration. When the bone is pulled apart, it tends to regenerate at the rate of approximately 1 mm per day.
Phases of Leg Lengthening Procedure
There are two phases of lengthening until the bone is healed:
- The distraction phase involves lengthening of the bone.
- The consolidation phase involves hardening and calcification of this new bone, which is still weak due to lack of calcium.
Limb Lengthening Devices
There are two types of devices available, external fixators and internal fixators. The external devices are attached to the bone with wires or threaded pins. The internal devices are placed inside your body, on the bone or inside the bone marrow.
Complications of Limb Lengthening Surgery
Bone complications include:
- Delayed union or non-union: Bone healing is delayed due to damage of bone tissues at the time of bone cutting.
- Premature consolidation: It occurs when the bone healing is abundant or fast.
- Axial deviation: It occurs because of unbalanced forces that bend the bone during the lengthening process.
Soft tissue complications include:
- Muscle contractures: This occurs when the soft tissues cannot adapt to the changes in bone length.
- Muscle weakness: It is caused by lack of movement because of the inability to walk normally.
- Nerve injury: This occurs when certain nerves do not stretch in coordination with the bone lengthening.
