The Journal of Bone and Joint Surgery (American) 85:831-837 (2003)
© 2003 The Journal of Bone and Joint Surgery, Inc.
Cyclic Loading of Olecranon Fracture Fixation Constructs
Douglas T. Hutchinson, MD,
Daniel S. Horwitz, MD,
Gregory Ha, MD,
Cameron W. Thomas, BS and
Kent N. Bachus, PhD
Investigation performed at the Department of Orthopaedics, University of Utah Health Sciences Center, Salt Lake City, Utah
Douglas T. Hutchinson, MD
Daniel S. Horwitz, MD
Gregory Ha, MD
Department of Orthopaedics, University of Utah Health Sciences Center, 50 North Medical Drive, Salt Lake City, UT 84132
Cameron W. Thomas, BS
Kent N. Bachus, PhD
Orthopaedic Bioengineering Research Laboratory, University of Utah, 20 South 2030 East (190 BPR), Salt Lake City, UT 84112
The authors did not receive grants or outside funding in support of their research or preparation of this manuscript. They did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated. Synthes donated the screws that were used in the test.
Background: Despite the good results that are usually reported after fixation at the sites of olecranon fractures and osteotomies, problems such as loss of fixation, nonunion, and the need for revision surgery are still encountered. Various types of fixation have been recommended, but few have been evaluated with use of clinically relevant cyclic load testing at appropriate levels of stress. The purpose of the present study was to test multiple olecranon fixation techniques under physiologic cyclic loads.
Methods: We studied ten cadaveric elbows with use of cyclic loading that simulated (1) active range of motion and (2) pushing up from a chair. Each specimen underwent fixation of a simulated 50% transverse olecranon fracture with use of intramedullary and cortically fixed tension band constructs (in randomized order) followed by fixation with a 7.3-mm-diameter cancellous screw with and without a tension band. Displacement transducers were placed posteriorly on the tension side and anteriorly near the articular surface.
Results: Both configurations involving the 7.3-mm-diameter cancellous screw provided the most stable fixationnearly five times better than that provided by the Kirschner-wire techniques. Use of the tension band in conjunction with the intramedullary screw improved the stability of fixation. In none of the constructs did the AO tension band result in compression across the osteotomy gap.
Conclusions and Clinical Relevance: The use of a 7.3-mm screw in conjunction with a tension band provided better fixation of simulated displaced transverse fractures than did the use of Kirschner wires in conjunction with a tension band or the use of a screw only. The AO principle of converting posterior tensile forces to articular compressive forces was not demonstrated in this study. We therefore question the validity of the tension band concept in olecranon fracture fixation and recommend passive rather than active range of motion in the immediate postoperative period to limit fracture distraction.

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