Validation of a proposed radiographic bone defect classification system

•A skeletal defects classification scheme is an important step towards standardising the assessment of these complex injuries.•Interobserver reliability testing demonstrated the proposed classification system had substantial agreement between observers.•Intraobserver variability showed a range of substantial to almost perfect agreement of each observer following a three-week interval.•The classification scheme is based primarily on conventional orthogonal radiographs, requiring no sophisticated technology or elaborate calculations.•The distinction between the various elements of the classification scheme are consistent with the prior orthopaedic trauma literature. To clinically validate a recently proposed classification scheme of post-traumatic bone defects. Open fractures were classified utilising a newly introduced classification system. This classification system is based on plain radiographs, assessing the extent and local geometry of bone loss, including: D1 - Incomplete Defects; D2 - Minor/Sub-Critical (Complete) Defects (