Evaluation of humeral head replacements using time-action analysis.

New surgical technologies are often introduced without objective evaluation of their efficiency. Commonly, their results are only related to surgical outcome and complication rate. In this study, time-action analysis was applied to evaluate the per-operative process and to measure surgical performance during 8 humeral head replacements. An overview of the operative theater and a detailed view were recorded on video simultaneously. The duration and number of actions grouped to functions, limitations, and repeated actions were determined. The duration and number of performed actions varied between procedures. The efficiency of the procedure, defined as the percentage of goal-oriented functions, was about 55%. Repeated actions were frequently observed during the alignment and insertion phase. We conclude that time-action analysis can be used to evaluate surgical performance objectively. Limitations of the surgical process that can be improved could be identified. These findings enable the evaluation of new operative techniques, protocols, and instruments.