title: A new method of fixation in osteoporotic bone. A preliminary report.
abstract: Over-tightening of cortical bone screws in osteoporotic bone results in weak fixation. Once a screw is over-tightened and the bone thread form is stripped, there are limited means at the surgeon's disposal to rescue the situation, none of them entirely satisfactory. We describe a simple device that is specifically designed to resolve this problem. It consists of a nylon cavity plug and applicator. The plug is inserted into the stripped hole and the screw re-applied and tightened in the normal manner. The plug expands and forms a load-bearing region on the inner face of the bone. Tests on osteoporotic cadavaric bone have shown that the plug effectively re-establishes screw fixation. When compared to an over-tightened screw, the plug is at least twice as resistant to loads acting to pull the screw out of the surrounding bone.
authors.affiliation: Department of Orthopaedic and Trauma Surgery, University of Dundee, Ninewells Hospital & Medical School, DD1 9SY, Dundee, UK. t.dre@dundee.ac.uk
authors.forename: Tim
authors.initials: T
authors.lastname: Drew
authors.forename: Paul
authors.initials: P
authors.lastname: Allcock
mesh_terms: D001863:Bone Screws; D001842:Bone and Bones / Q000601:surgery*; D004867:Equipment Design; D004868:Equipment Failure; D005592:Fracture Fixation / Q000295:instrumentation* / Q000379:methods; D050723:Fractures, Bone / Q000150:complications / Q000601:surgery*; D006801:Humans; D010024:Osteoporosis / Q000150:complications / Q000601:surgery*