title: [Studies of femoral neck fractures--biomechanical experiments with various devices for internal fixation with follow-up study on clinical cases-- (author's transl)].
abstract: The Tri-cancellous compression screw method was developed in order to overcome some defects which we feel exist in other methods of fixation presently in use. The author has conducted studies on the stability of the Tri-cancellous compression screw method and on the results of its clinical use. The conclusions are as follows: 1) In compression and torsion tests, the Tri-cancellous compression screw method showed greater strength than other methods. 2) The holding strength in cancellous bone of the screw is determined solely by its outside diameter and is never influenced by its thread profile and pitch. 3) The stability of the Tri-cancellous compression screw method decreases every hour postoperatively. 4) Clinically, when the Tri-cancellous compression screw method was correctly used, we found no evidence of the development of non-union. However, late segmental collapse has remained a problem of the same level as when other methods are used.
mesh_terms: D000368:Aged; D000818:Animals; D001696:Biomechanical Phenomena; D001858:Bone Nails; D001863:Bone Screws; D005260:Female; D005265:Femoral Neck Fractures / Q000601:surgery*; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000295:instrumentation / Q000379:methods*; D006245:Hardness Tests; D006801:Humans; D008297:Male; D013552:Swine