Bone lengthening procedures (24420, 25391, 25393, 27466, 27715) are considered medically necessary for the correction of congenital or post-traumatic limb length discrepancies and angular deformities of the limb (arm, forearm, thigh or leg) (736.01, 736.02, 736.3-736.32, 736.4-736.42, 736.81, 755.24-755.27, 755.34-755.37, 755.59, 755.69). Specific indications include:

• demonstrable non-union or mal-union of long bone with or without bone loss or infection;
  

  NOTE:

  Non-union/mal-union is defined as not having united within a minimum of three months of the original trauma.

• where lengthening of an amputation stump is needed for proper fitting of a prosthesis;
• where leg lengthening is needed to equalize leg length discrepancy greater than 6 cm and for correction of congenital or post-traumatic angular-rotational deformations of the long bones;
• when used for bone defects with or without deformities.

Bone lengthening for conditions other than the above is not medically necessary and, therefore, is not eligible for payment. A participating, preferred, or network provider cannot bill the member in this instance.

Description

The Ilizarov method is based on the biological principle of "tension stress." According to this principle, gradual controlled distraction of the bone ends not only stimulates bone production but also supports the regeneration of the overlying tissue. This is achieved through use of a special osteotomy-corticotomy technique which involves transection of only the bone cortices.

The Ilizarov technique involves the use of a circular external fixator device (20690, 20692) which is attached to the bone by transfixion wires. A corticotomy (percutaneous osteotomy) is performed to permit attachment of the wires. Periodic adjustment of the external fixator then produces a distractive lengthening force, which gradually stimulates new bone growth.