Lumbar plexus block with ultrasound-guided shamrock technique: In-plane versus novel out-of-plane approach.

Study Summary

40 patients undergoing surgery for femoral neck fractures were randomized to receive an ultrasound-guided lumbar plexus block using either the in-plane or out-of-plane Shamrock technique. The primary outcome of interest was block procedure time. Secondary outcomes included the number of needle insertions and redirections, needle depth, minimum nerve stimulation intensity, sensory and motor block onset, epidural spread, and complications. Outcomes were assessed during block performance and through the perioperative period. Overall, the results of the study revealed no significant difference in block procedure time between techniques, while the out-of-plane approach required fewer needle insertions and redirections and a shallower needle depth. These findings suggested that the out-of-plane Shamrock technique provided similar block efficacy and safety with potential technical advantages over the in-plane approach, particularly in elderly patients.