Rating of internal fixation and clinical outcome in displaced femoral neck fractures: a prospective multicenter study.

The influence of precise surgical technique on the clinical outcome of internal fixation for displaced femoral neck fractures is an under-reported and potential confounding factor in randomized studies involving internal fixation as a treatment modality. Two experienced surgeons blindly rated internal fixation techniques on the perioperative radiographs of 102 patients selected for internal fixation in a prospective multicenter 2-year followup study. Overall technical, fracture reduction, and implant positioning ratings were given according to instruction. One or both raters assigned an inadequate overall rating in 25% of patients. There was a correlation with 2-year clinical internal fixation failure for overall technique and fracture reduction rating. Implant positioning did not correlate with 2-year internal fixation failure. Correlation increased if both raters agreed on inadequate technique. One inadequate rating indicated a problem could arise, whereas two inadequate ratings strengthened this problem likelihood. Adjudication of technique by independent rater(s) is useful, may have clinical implications, and should be performed routinely in future studies involving internal fixation in patients with displaced femoral neck fractures.