Implantable hydraulic bone expansion device

摘要

The bone expansion device uses a hydraulic system comprising a hydraulic actuator unit (5) filled with gel (7) containing valves (11), to control the supply by a reservoir (12). Tubing (6) connects the reservoir to the actuator unit and supplies the cylinder (14) with fluid from the actuator. Biocompatible screws (3) are fixed directly into the bone and attached to the cylinder housing (14') and piston housing (15'). The entire hydraulic bone expansion unit is implanted beneath the skin. The bone to be lengthened is broken in two and the expansion unit fixed across the gap by means of biocompatible screws. The hydraulic expander is controlled by a hydraulic pump operated by pressure applied to the skin, or by an implanted electric pump operated by induction from outside the body. Pressure applied on the piston makes the gap between the bone sections wider. This carried out repeatedly once a bony graft has been formed between the two sections.