The ipsilateral olecranon tip is a suitable anatomic autograft for unrepairable coronoid fractures: A comparative three-dimensional mapping analysis.

Background: Perform computed tomography (CT) three-dimensional (3D) mapping analysis of the ipsilateral olecranon tip to determine its suitability as an autograft for unrepairable coronoid fractures.

Methods: CT was evaluated using Mimics 13.0 and 3-matic software (Materialise, Inc., Leuven, Belgium). Coronoid fracture fragment was measured from the medial sublime tubercle to the halfway point of the proximal radioulnar joint. Ipsilateral olecranon tip graft was measured at the equivalent height of the coronoid fragment and the angle of graft "cut" necessary to match the coronoid fragment was measured. The overall width of each graft site was measured in thirds and the congruity of surface geometry was measured by overlapping both fragments. The ipsilateral olecranon tip lateral facet which rotates to become the coronoid medial facet was also measured.

Results: The olecranon tip and coronoid fragments were similar in average maximum height and width. The average angle of graft cut needed to match the coronoid fragment was 86°. The average difference between the medial facet of the coronoid and lateral facet of the olecranon was <2 mm.

Discussion: The ipsilateral olecranon tip can be harvested through the same surgical incision and function as a local autograft during reconstruction of unrepairable coronoid fractures.