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.

High efficiency lunate-tail swimming with high-aspect-ratio lifting surfaces has evolved in many vertebrate lineages, from fish to cetaceans. Baleen whales (Mysticeti) are the largest swimming animals that exhibit this locomotor strategy and present an ideal study system to examine how morphology and the kinematics of swimming scale to the largest body sizes. We used data from whale-borne inertial sensors coupled with morphometric measurements from aerial drones to calculate the hydrodynamic performance of oscillatory swimming in six baleen whale species ranging in body length from 5-25m (fin whale, Balaenoptera physalus; Bryde's whale, Balaenoptera edeni; sei whale, Balaenoptera borealis; Antarctic minke whales, Balaenoptera bonaerensis; humpback whales, Megaptera novaeangliae; and blue whales, Balaenoptera musculus). We find that mass-specific thrust increases with both swimming speed and body size. Froude efficiency, defined as the ratio of useful power output to the rate of energy input (Sloop, 1978), generally increased with swimming speed but decreased on average with increasing body size. This finding is contrary to previous results in smaller animals where Froude efficiency increased with body size. Although our empirically-parameterized estimates for swimming baleen whale drag was higher than that of a simple gliding model, oscillatory locomotion at this scale exhibits generally high Froude efficiency as in other adept swimmers. Our results quantify the fine-scale kinematics and estimate the hydrodynamics of routine and energetically expensive swimming modes at the largest scale.

Objectives:Nerve block administration in concert with general anesthesia can help manage post-operative pain and provide favorable muscle relaxation of the operative leg in hip surgery. However, the optimal nerve blockade_if any_for arthroscopic surgery of the hip remains undefined. Considerations specific to hip arthroscopy include control of intra-operative pain, adequate muscle relaxation to allow for distraction for work in the central compartment, and post-operative pain control. Dold et al. recently reported in AJSM that a pre-operative femoral nerve block administered in concert with general anesthesia led to decreased patient-reported pain scores at the 60 minute mark post-operatively. Given this demonstrated benefit of the pre-operative femoral nerve block, we hypothesized that a regional block that anesthetized the femoral nerve and the lateral femoral cutaneous nerve (as the fascia iliaca block does), or one that anesthetized the obturator nerve in addition to the femoral and lateral femoral cutaneous nerves (i.e. the lumbar plexus block), would provide additional benefit. The purpose of this study is to examine the effects of pre-operative fascia iliaca and lumbar plexus nerve blocks on post-operative pain and secondary post-operative variables following arthroscopic surgery of the hip.Methods:A retrospective chart analysis was conducted on 145 patients undergoing arthroscopic surgery of the hip in 3 groups. Group 1 (n=55) received general anesthesia only, Group 2 (n=30) received general anesthesia and a fascia iliaca nerve block, and Group 3 (n=60) received general anesthesia and a lumbar plexus nerve block. Post-operative measures were recorded, examined and compared. The primary outcome measure was patient reported pain scores (0-10) at 0, 30, 60, 90 and 120 minutes in the post-anesthesia care unit (PACU). Secondary variables examined included time spent in the PACU, morphine equivalent administered, and presence of nausea requiring anti-emetic medication.Results:Mid-term analysis revealed no benefit to the fascia iliaca block; this regional anesthesia technique showed no significant effect on any of the measured post-operative variables when compared to general anesthesia alone. We therefore abandoned this block in favor of the lumbar plexus block. Patients receiving a lumbar plexus block exhibited significantly decreased pain at each time point when compared to the fascia iliaca group, and at all but one time point when compared to the general anesthesia group (P<0.05). There was no difference in the time spent in the PACU, nor in morphine equivalent administered between any of the groups.Conclusion:The results of the current study indicate that for arthroscopic surgery of the hip, a pre-operative lumbar plexus regional block performed in conjunction with general anesthesia provides significant and clinically meaningful decreases in post-operative pain reported in the PACU when compared with general anesthesia alone or general anesthesia with fascia iliaca block. This relative benefit we found in...