Surgical prosthetic fixing with self cutting screw threads - having abrasive coating to facilitate insertion and improve screw grip

Abstract

Abstract A surgical prosthetic fixing esp. for artificial joints and limbs has self-cutting screw threads to engage in the bone of a patient. The threads are axially fluted or otherwise discontinuous to provide clearance for bone cuttings. Methods of mfr. and inserting the fixing are also claimed. The screw thread surface has a biocompatible coating capable of abrasive action, pref. by virture of contg. abrasive particles of apatite of a calcium hydroxide base. The particles should have a grain size 0.7mm, pref. between 0.2-0.4 mm. As an alternative to apatite, the abrasive particles may be grains of quartz sand. The abrasive content of the coating is pref. between 20 and 60wt. % with a balance of enamel. Insertion of the self-cutting screw is facilitated and security improved by simultaneously imposing angular oscillations = plus-or-minus 2 degrees at a frequency of >=20 Hz.

Inventors

• 👤 Helmut Prof Dr Ing Grell
• 👤 Heinz Dipl Chem Scharbach

Bibliographic Details