Endoscopic removal of PMMA in hip revision surgery with a CO 2 laser

Abstract

Purpose: to compare CO 2 laser to mechanical means of PMMA removal in total hip arthroplasty revision surgery. Materials and methods: Forty-five patients requiring hip revision surgery were studied and compared to historical controls. Cement was removed from the femoral canal utilizing a 30 centimeter laparoscope. A CO 2 laser waveguide was passed through the laparoscope into the femoral canal and a TV camera was placed over the eye piece to permit visualization of the depths of the femoral canal on a video monitor. The leg was placed in a horizontal position which avoided the pooling of blood or saline in the depths of the femur. Under direct vision the distal plug could be vaporized with a 40 centimeter CO 2 laser waveguide. Power settings of 20 to 25 watts and a superpulsed mode were used. A 2 mm suction tube was welded to the outside of the laparoscope permitting aspiration of the products of vaporization. Results: Of 45 hip revisions there were no shaft perforation, fractures or undue loss of bone stock. There was no statistically different stay in hospital time, blood loss or operative time between the CO 2 revision group compared to the non-laser revision group, in which cement was removed by mechanical methods. Conclusions: Mechanical methods used in removing bone cement using high speed burrs, reamers, gouges, and osteotomies is technically difficult and fraught with complications including shaft fracture, perforations, and unnecessary loss of bone stock. The authors' experience using the CO 2 laser in hip revision surgery has permitted the removal of bone cement. Use of a modified laparoscope has allowed for precise, complete removal of bone cement deep within the femoral shaft without complication or additional operative time. The authors now advocate the use of a CO 2 laser with modified laparoscope in hip revision surgery in which bone cement is to be removed from within the femoral shaft.