Defining displacement thresholds for surgical intervention for distal radius fractures – A Delphi study

Distal radius fractures are very common yet controversy exists regarding which require treatment and is reflected by significant variation in surgical intervention rate. Evidence regarding which fractures would benefit from intervention is varied and largely poor quality. This study had three aims; identify which radiographic parameters are clinically important; quantify the threshold of displacement at which intervention should occur and investigate which patient factors influence the decision to intervene. A modified three round Delphi study was carried out and responses were qualitatively analysed. The Delphi panel was composed of three groups of national and international expert surgeons: hand and wrist surgeons, trauma surgeons, and international researchers. 46 participants initially agreed to take part. 43 completed the first round and all then completed three rounds. Participants were asked questions based around case vignettes in patients of three ages (38, 58, 75 years). For all age groups ulnar variance was ranked as the most important extra-articular parameter, step was ranked as the most important intra-articular parameter. Agreed thresholds were the same for all parameters for patients aged 38 and 58. Surgeons would intervene with +2 mm ulnar variance, 10 degrees dorsal tilt, 2mm step and 3mm gap. In patients aged 75 the agreed thresholds were 20 degrees dorsal tilt, 3mm step and 4mm gap, consensus was not achieved for ulnar variance. Mental capacity, pre-injury functional level and medical co-morbidities were ranked as the most important factors influencing the decision to intervene. Qualitative analysis suggested that pre-injury function was the main theme within these factors. Our findings provide useful advice about which parameters should be measured and radiographic thresholds for intervention. These thresholds may then be modified depending on important patient factors. This information can help guide clinicians with management decisions and reduce variation.