Shape memory alloy internal linear actuator for use in orthopedic correction

摘要

An implantable linear actuator device for use in orthopedic correction procedures, the device comprising a housing including a first tubular portion and a second tubular portion, the second tubular portion slidably received in telescoping relationship within the first tubular portion; and a drive mechanism secured within the housing and connected between the first and second tubular portions, the drive mechanism including a main screw shaft rotatably journalled at one end in the first tubular portion and threadably connected at an opposite end to the second tubular portion; a one-way rotatable clutch engageable with the main screw shaft such that rotation of the clutch in one direction will effect rotation of the main screw shaft in the one direction but rotation of the clutch in an opposite direction will not rotate the main screw shaft; and a shape memory alloy component fixed between the clutch and the first tubular portion such that, upon application of heat, the component causes the clutch and the screw shaft to rotate in the one direction.