Pre-operative lumbar plexus block provides superior post-operative analgesia when compared with fascia iliaca block or general anesthesia alone in hip arthroscopy.

The objective of this study is to retrospectively examine the effects of pre-operative fascia iliaca (FI) and lumbar plexus (LPB) nerve blocks on post-operative pain and secondary post-operative variables following arthroscopic surgery of the hip. Subjects undergoing arthroscopic surgery of the hip received one of three pre-operative anesthetic techniques; general anesthesia only, general anesthesia with FI or general anesthesia with LPB. Patient reported pain scores (0-10) were recorded at 0, 30, 60, 90 and 120 min after admission to the post-anesthesia care unit (PACU). Secondary variables examined include time spent in the PACU, morphine equivalent administered, presence of nausea, persistent numbness, parasthesia, weakness, increased narcotic usage for rebound pain, ED visits and hospital admissions. The mean pain scores over all time points were significantly lower in the LPB group (2.38) than the FI group (4.08, P  <   0.001) and the Gen group (3.55, P  <   0.001). Patients receiving a lumbar plexus block exhibited significantly decreased pain at t  = 0 ( P  =   0.019), t  = 30 ( P  =   0.038), t  = 60 ( P  =   0.013), t  = 90 ( P  =   0.017) and t  = 120 ( P  =   0.001) after admission to PACU. The FI group showed no improvement in any post-operative variable when compared with general anesthesia alone. There was no difference in the time to discharge or in morphine equivalent administered between groups. One patient receiving a lumbar plexus block experienced a seizure lasting about 10 s. However, there were no medium or long-term complications. Lumbar plexus block administered in concert with general anesthesia provides clinically important and statistically significant post-operative pain relief when compared with general anesthesia alone or general anesthesia plus fascia iliaca block.