Hrayr G Basmajian1, Joseph N Liu2, Travis Scudday3, Seth T Campbell4, Nirav H Amin5. 1. Premier Orthopaedic and Trauma Specialists 160 E. Artesia Street, Suite 310, Pomona, CA 91767, USA. 2. Loma Linda University, Department of Orthopedics, 24851 Circle Dr, Loma Linda, CA 92354, USA. 3. Orthopaedic Specialty Institute Medical Group of Orange County, 280 South Main Street, Suite 200, Orange, CA 92868, USA. 4. Loma Linda University, 24851 Circle Drive, Loma Linda, CA 92354, USA. 5. Restore Orthopedic and Spine Center, 1120 W. La Veta Avenue, Suite #300, Orange, CA 92868, USA.
Abstract
OBJECTIVES: To compare the pullout strength and maximal insertional torque of pilot holes prepared with the traditional twist drill bit versus a smooth Kirschner wire. METHODS: Pilot holes were prepared using a drill press with either a 2.5 mm twist drill bit or a 2.5 mm smooth Kirschner wire into 2 distinct polyurethane foam densities representing severe and mild osteoporotic bone. 3.5 mm cortical and 4.0 mm cancellous screws were then inserted freehand into the prepared holes. All permutations of pilot hole type, screw size and foam density were tested for maximum pullout strength and maximum insertional torque. RESULTS: Kirschner wire prepared pilot holes resulted in significantly higher pullout load than drill bit holes in low density blocks (P < 0.001), but not in high density blocks (P = 0.232). There was no statistical difference (P > 0.05) for maximum insertional torque in the pilot hole preparation type. CONCLUSION: In severely osteoporotic bone, Kirschner wire pilot hole preparation may improve screw pullout strength.
OBJECTIVES: To compare the pullout strength and maximal insertional torque of pilot holes prepared with the traditional twist drill bit versus a smooth Kirschner wire. METHODS: Pilot holes were prepared using a drill press with either a 2.5 mm twist drill bit or a 2.5 mm smooth Kirschner wire into 2 distinct polyurethane foam densities representing severe and mild osteoporotic bone. 3.5 mm cortical and 4.0 mm cancellous screws were then inserted freehand into the prepared holes. All permutations of pilot hole type, screw size and foam density were tested for maximum pullout strength and maximum insertional torque. RESULTS: Kirschner wire prepared pilot holes resulted in significantly higher pullout load than drill bit holes in low density blocks (P < 0.001), but not in high density blocks (P = 0.232). There was no statistical difference (P > 0.05) for maximum insertional torque in the pilot hole preparation type. CONCLUSION: In severely osteoporotic bone, Kirschner wire pilot hole preparation may improve screw pullout strength.
Authors: William M Ricci; Paul Tornetta; Timothy Petteys; Darin Gerlach; Jacob Cartner; Zakiyyah Walker; Thomas A Russell Journal: J Orthop Trauma Date: 2010-06 Impact factor: 2.512
Authors: Sara E Tankard; Simon C Mears; Daniel Marsland; Evan R Langdale; Stephen M Belkoff Journal: J Orthop Trauma Date: 2013-04 Impact factor: 2.512