Expandable Non-invasive Prostheses - an Alternative to Pediatric Patients with Bone Sarcoma.

In the paper the problem of joint arthroplasty in children who have not reached their maturity is raised. The arthroplasty concerns replacement of a joint that does not function due to bone sarcoma that a child suffers from. Osteosarcoma and Ewing's sarcoma are the most common types of pediatric bone cancer and they afflict mainly long bones, i.e. femur and tibia. In such cases there are only two options: to amputate the affected limb or to replace the diseased bone. It goes without saying that the latter solution is most acceptable by patient and surgeon. However, a special prosthesis has to be applied as the limbs still grow. To avoid leg length discrepancy between the healthy limb and the affected one expandable prostheses are inserted. Specific designs of such prostheses allow one to lengthen the operated limb and preserve the same length of the two legs. In the paper an overview of expandable prostheses is presented. Also our own designs of expandable orthopaedic devices are shown. The devices are characterised by the fact that their length can be intelligently extended by means of a special electro-magnetic set.