Iliopsoas plane (IP) is a fascial plane deep to the iliopsoas complex that can serve as a potential space for the injection of local anesthetics to selectively block the articular branches of femoral nerve and accessory obturator nerve to the anterior hip capsule. Two highly similar ultrasound-guided interfascial plane blocks that target the IP, pericapsular nerve group (PENG) block and iliopsoas plane block (IPB), were both designed to achieve motor-sparing sensory block to the anterior hip capsule. However, the most recent evidence shows that PENG block can cause 25% or more of quadriceps weakness, while IPB remains the hip block that can preserve quadriceps strength. In this scoping review of quadriceps weakness after PENG block and IPB, we first performed a focused review on the complicated anatomy surrounding the anterior hip capsule. Then, we systematically searched for all currently available cadaveric and clinical studies utilizing PENG block and IPB, with a focus on quadriceps weakness and its potential mechanism from the perspectives of fascial plane spread along and outside of the IP. We conclude that quadriceps weakness after PENG block, which places its needle tip directly deep to iliopsoas tendon (IT), may be the result of iliopectineal bursal injection. The incidental bursal injection, which can be observed on ultrasound as a medial fascial plane spread, can cause bursal rupture/puncture and an anteromedial extra-IP spread to involve the femoral nerve proper within fascia iliaca compartment (FIC). In comparison, IPB places its needle tip lateral to IT and injects just one-fourth of the volume of PENG block. The current evidence, albeit still limited, supports IPB as the true motor-sparing hip block. To avoid quadriceps weakness after PENG block, a more laterally placed needle tip, away from the undersurface of IT, and a reduction in injection volume should be considered. Future studies should focus on comparing the analgesic effects and quadriceps function impairment between PENG block and IPB.

Objective: Discrepancies in the definition of adductor canal block (ACB) lead to inconsistent results. To investigate the actual analgesic and motor-sparing effects of ACB by anatomically defining femoral triangle block (FTB), proximal ACB (p-ACB), and distal ACB (d-ACB), we re-classified the previously claimed ACB approaches according to the ultrasound findings or descriptions in the corresponding published articles. A meta-analysis with subsequent subgroup analyses based on these corrected results was performed to examine the true impact of ACB on its analgesic effect and motor function (quadriceps muscle strength or mobilization ability). An optimal ACB technique was also suggested based on an updated review of evidence and ultrasound anatomy. Materials and Methods: We systematically searched studies describing the use of ACB for knee surgery. Cochrane Library, PubMed, Web of Science, and Embase were searched with the exclusion of non-English articles from inception to 28 February 2022. The motor-sparing and analgesic aspects in true ACB were evaluated using meta-analyses with subsequent subgroup analyses according to the corrected classification system. Results: The meta-analysis includes 19 randomized controlled trials. Compared with the femoral nerve block group, the quadriceps muscle strength (standardized mean difference (SMD) = 0.33, 95%-CI [0.01; 0.65]) and mobilization ability (SMD = −22.44, 95%-CI [−35.37; −9.51]) are more preserved in the mixed ACB group at 24 h after knee surgery. Compared with the true ACB group, the FTB group (SMD = 5.59, 95%-CI [3.44; 8.46]) has a significantly decreased mobilization ability at 24 h after knee surgery. Conclusion: By using the corrected classification system, we proved the motor-sparing effect of true ACB compared to FTB. According to the updated ultrasound anatomy, we suggested proximal ACB to be the analgesic technique of choice for knee surgery. Although a single-shot ACB is limited in duration, it remains the candidate of the analgesic standard for knee surgery on postoperative day 1 or 2 because it induces analgesia with less motor involvement in the era of multimodal analgesia. Furthermore, data from the corrected classification system may provide the basis for future research.

Background: Piriformis syndrome (PS) is a painful musculoskeletal condition characterized by a deep gluteal pain that may radiate to the posterior thigh and leg. This study was designed to compare the effectiveness of ozone and BTX to lidocaine injection in treating piriformis syndrome that was resistant to medication and/or physical therapy. Study design: Between November 2018 and August 2019, we involved eighty-four subjects diagnosed with piriformis syndrome in a double-blinded, prospective, randomized comparative study to receive an ultrasound-guided injection of lidocaine (control group), botulinum toxin A, or local ozone (28 patients each group) in the belly of the piriformis muscle. Pain condition evaluated by the visual analog score (VAS) was used as a primary outcome, and the Oswestry Disability Index (ODI) as a secondary outcome, before, at one month, two months, three months, and six months following the injection. Results: The majority (58.3%) of patients were male, while (41.7%) were female. At one month, a highly significant decrease occurred in VAS and ODI in the lidocaine and ozone groups compared to the botulinum toxin group (p < 0.001). At six months, there was a highly significant decrease in VAS and ODI in the botulinum toxin group compared to the lidocaine and ozone groups (p < 0.001). Conclusion: Botulinum toxin may assist in the medium- and long-term management of piriformis syndrome, while lidocaine injection and ozone therapy may help short-term treatment in patients not responding to conservative treatment and physiotherapy.

The erector spinae plane block (ESPB) at the level of the fifth thoracic vertebra (T5) is a novel technique, first published in 2016, which was found to be effective in both acute and chronic pain control. The mechanism of action and spread of local anesthetic of the ESPB at the lumbar region are thought to differ from those of the thoracic ESPB; however, the difference in onset time has never been evaluated. As for the onset of lumbar ESPBs, we presented three cases: two received lumbar ESPBs (one with chronic low back pain and one with acute postoperative hip pain), and the third one with chronic back pain received a thoracic ESPB. We administered 30 mL of 0.3% ropivacaine in all three patients, but the analgesic effect did not reach its maximum until 3 and 1.5 h, respectively, in the lumbar ESPB cases. On the contrary, the thoracic ESPB case experienced noticeable pain relief within 30 min. The onset time was considerably longer than that reported in earlier reports on ESPBs, and the lumbar ESPB achieved its peak effect much later than the thoracic ESPB using the same formula of local anesthetic. While the delayed-onset lumbar ESPB may have some drawbacks for treating acute postoperative pain, it still could produce significant analgesia, once it took effect, when given to patients suffering from hip surgery with large incisions and intractable low back pain. The current data suggested that the onset time of a lumbar ESPB may be delayed compared with its thoracic counterpart. Therefore, the local anesthetic formula and injection timing should be adjusted for a lumbar ESPB when applied in the perioperative period to make the onset of the analgesic effect coincide with the immediate postoperative pain. Without this concept in mind, clinicians may consider a lumbar ESPB to be ineffective before it takes effect, and consequently treat the patients inadequately with this technique. Future randomized controlled trials should be designed according to our observations to compare lumbar ESPB with its thoracic counterpart regarding onset time.

(1) Introduction: The aim was to describe the anesthetic and surgical technique of eversion carotid endarterectomy performed under intermediate-deep cervical block with sedation, and to analyze the intraoperative and postoperative results. (2) Material and Methods: Thirty cases of unilateral eversion carotid endarterectomy (n = 30), performed between 2019–2020 in a tertiary center under intermediate-deep ultrasound-guided cervical plexus block and sedation, were prospectively observed and analyzed. Hemodynamic (blood pressure, heart rate) and neurological (cerebral oximetry) variables were measured in four intraoperative phases: at the beginning of the operation, prior to carotid clamping, after unclamping and at the end of the operation. We assessed acute postoperative pain in a numerical rating scale at 6, 12 and 24 h, early and 30-day complications, and length of stay. (3) Results: Baseline mean arterial pressure values were 100.4 ± 18 mmHg, pre-clamping 95.8 ± 14 mmHg, post-clamping 94.9 ± 11 mmHg, and at the end of the operation 102.4 ± 16 mmHg. Cerebral oximetry values were 61.7 ± 7/62.7 ± 8, 68.5 ± 9.6/69.1 ± 11.7 and 68.1 ± 10/68.1 ± 10 for the left and right hemispheres at baseline, pre- and post-clamping, respectively. The pain assessment showed a score less than or equal to 3. The incidence of residual nerve block, early complications, and major complications in the first 30 days was 40%, 16.7% and 3.3%, respectively. (4) Conclusions: The combination of intermediate-deep cervical plexus block and low-dose sedation is an effective and safe alternative in awake eversion carotid endarterectomy.

Background: Until now, target-controlled infusion of remifentanil with midazolam for transrectal ultrasound-guided prostate biopsy has not been described. Here, we investigate 2 effect-site concentrations of remifentanil with intermittent bolus midazolam for transrectal ultrasound-guided prostate biopsy under procedural analgesia and sedation. Methods: A prospective, randomized controlled trial including patients who received a transrectal ultrasound-guided prostate biopsy between February 2019 and January 2021 was conducted. Group 1 and Group 2 were respectively administered an initial effect-site concentration of remifentanil of 1.0 ng/mL and 2.0 ng/mL by a target-controlled infusion pump with Minto model. In both groups, maintenance of the effect-site concentration of remifentanil was adjusted upward and downward by 0.5 ng/mL to keep patient comfort with acceptable pain (remaining moveless), and mean arterial pressure and heart rate within baseline levels ± 30%, and using intermittent bolus midazolam to keep the Observer’s Assessment of Alertness/Sedation scale between 2 and 4. The primary outcome was to determine which effect-site concentration of remifentanil provide adequate patient comfort with acceptable pain (remaining moveless) during the procedure. Results: A total of 40 patients in Group 1 and 40 patients in Group 2 were eligible for analysis. Most parameters were insignificantly different between Group 1 and Group 2, except Group 1 having higher peripheral oxygen saturation while probe insertion compared with Group 2. Group 2 patients had less intraoperative movements affecting the procedure (2 vs 18; P < .001), and less total times of target-controlled infusion pump adjustment (0 [0–1] vs 1 [0–3], P < .001) compared with group 1. However, group 1 patients had less apnea with desaturation (peripheral oxygen saturation < 90%; 0 vs 9, P = .002) and less remifentanil consumption (94.9 ± 25.5 μg vs 106.2 ± 21.2 μg, P = .034) compared to Group 2. Conclusion: In transrectal ultrasound-guided prostate biopsy, target-controlled infusion with remifentanil Minto model target 2.0 ng/mL with 3 to 4 mg midazolam use provided sufficient analgesia and sedation, and appropriate hemodynamic and respiratory conditions.