title: Holding power of orthopedic screws in the large metacarpal and metatarsal bones of calves.
abstract: Holding power was determined for various orthopedic screws in bones of calves. Holding power was defined as maximal tensile force required to remove a screw divided by thickness of bone engaged by the screw (kN/mm). Comparative pull-out tests were performed, using pairs of large metacarpal or metatarsal bones from calves aged 3 to 14 days. Comparisons were made of the holding power of 6.5-mm fully threaded cancellous screws and 5.5-mm cortical screws in the proximal and distal metaphyses, and of 4.5-mm and 5.5-mm cortical screws in the diaphysis. Sixteen repetitions of each comparative trial were performed. There was no statistically significant difference in the holding power of 4.5- and 5.5-mm cortical screws in the diaphysis. There was no significant difference in the holding power of 5.5-mm cortical and 6.5-mm fully threaded cancellous screws in the proximal metaphysis. In the distal metaphysis, 6.5-mm fully threaded cancellous screws had significantly (P < 0.001) greater holding power than did 5.5-mm cortical screws. There was no significant difference between the mean holding power of 5.5-mm cortical screws in the proximal metaphysis and 5.5-mm cortical screws in the distal metaphysis. There was significantly (P < 0.01) greater mean holding power of 6.5-mm cortical, fully threaded cancellous screws in the distal metaphysis, compared with the proximal metaphysis.
authors.affiliation: Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606.
authors.forename: A T
authors.initials: AT
authors.lastname: Blikslager
authors.forename: K F
authors.initials: KF
authors.lastname: Bowman
authors.forename: C F
authors.initials: CF
authors.lastname: Abrams
authors.forename: T R
authors.initials: TR
authors.lastname: Seaboch
authors.forename: E L
authors.initials: EL
authors.lastname: Hunt
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001863:Bone Screws / Q000662:veterinary*; D002417:Cattle; D004867:Equipment Design; D050279:Metacarpal Bones; D008684:Metatarsus; D009985:Orthopedics / Q000662:veterinary*; D013718:Tensile Strength