De Qh Tran

Objective: Pericapsular nerve group block spares the main trunk of the femoral nerve, and its use has rapidly expanded from hip fracture surgery to total hip arthroplasty, where preservation of quadriceps function is paramount for early rehabilitation and ambulation. This systematic review investigated the analgesic and motor-sparing benefits of pericapsular nerve group block for total hip arthroplasty. Methods: This systematic review included randomized trials evaluating pericapsular nerve group block in adult patients undergoing total hip arthroplasty. Databases, including MEDLINE, EMBASE, CINAHL, and Google Scholar, were searched (inception through May 2026). Only randomized trials published in English, with prospective registration and without discrepancies between the registered and reported protocols, were retained for analysis. Results: Across 10 randomized trials, from an analgesic standpoint, pericapsular nerve group block was found to be noninferior to intrathecal morphine (100 µg) and superior to infrainguinal fascia iliaca block. Pericapsular nerve group block provided similar analgesia and breakthrough opioid consumption compared with suprainguinal fascia iliaca block, anterior quadratus lumborum block, and L4 erector spinae plane block; however, it may improve motor strength during the initial postoperative period. Combined lateral quadratus lumborum block–periarticular local anesthetic infiltration and combined pericapsular nerve group block–periarticular local anesthetic infiltration–lateral femoral cutaneous nerve block provided similar pain at rest and functional outcomes, although lateral quadratus lumborum block–periarticular local anesthetic infiltration achieved lower pain with movement and reduced opioid requirements. Compared with pericapsular nerve group block, periarticular local anesthetic infiltration resulted in lower dynamic pain (first 6 h) and static pain (first 48 h), and adding pericapsular nerve group block to a robust periarticular local anesthetic infiltration regimen provided minimal incremental benefit. Conclusion: Pericapsular nerve group block provided an equianalgesic, motor-sparing alternative to suprainguinal fascia iliaca block, anterior quadratus lumborum block, and lumbar erector spinae plane block for total hip arthroplasty. However, intrathecal morphine may provide comparable analgesia to pericapsular nerve group block. Furthermore, a robust periarticular local anesthetic infiltration regimen may outperform pericapsular nerve group block. Consequently, future large-scale trials are required to elucidate the benefits of pericapsular nerve group block compared with intrathecal morphine (for inpatient total hip arthroplasty) and periarticular local anesthetic infiltration (for inpatient and outpatient total hip arthroplasty). INPLASY registration number: INPLASY202670024.

Shoulder surgery for patients with pulmonary disease constitutes a unique dilemma. Over the last 10 years, multiple randomized trials have investigated diaphragm-sparing alternatives to interscalene brachial plexus block. In this Education Article, we review the essentials of our current understanding by discussing the innervation of the shoulder, definitions of hemidiaphragmatic paralysis, and the evidence supporting the different diaphragm-sparing nerve blocks. For each diaphragm-sparing strategy, we also identify remaining knowledge gaps and areas requiring further investigation.

Background: This randomized trial compared three admixtures of local anesthetic for ultrasound (US)-guided infraclavicular block (ICB): adrenalized bupivacaine 0.5%- dexamethasone 4 mg (group D0) versus adrenalized bupivacaine 0.5%- dexamethasone 4 mg- dexmedetomidine 0.67 µg/kg (group D1) versus adrenalized bupivacaine 0.5%, dexamethasone 4 mg- dexmedetomidine 1.33 µg/kg (group D2). We hypothesized that the D2 group would display a 30%-shorter onset time than the D1 group, which in turn would display a 30%-shorter onset time than the D0 group. Methods: After obtaining ethics committee approval, we recruited 104 patients undergoing upper limb surgery distal to the elbow. All subjects received 35 mL of bupivacaine 0.5%+epinephrine 5 µg/mL+perineural dexamethasone 4 mg. Patients were randomized to one of three perineural doses of dexmedetomidine (0 µg/kg, 0.67 µg/kg, or 1.33 µg/kg). The primary outcome was the onset time, defined as the time required to reach a minimal score of 14 points on a 16-point sensorimotor scale. The sensorimotor block was assessed every 5 min for 1 hour. Secondary outcomes included the incidence of surgical anesthesia, the duration of analgesia as well as sensorimotor block, and the occurrence of adverse events possibly related to dexmedetomidine (ie, bradycardia, hypotension, and oxygen desaturation). Results: Compared with the D0 group, both D1 and D2 groups resulted in shorter median onset times (20 [12.5–25.0] vs 25 [17.5–30.0] min; p=0.038 and 15 (15.0–20.0) vs 25 (17.5–30.0) min; p=0.003, respectively). No statistical differences were found between the D1 and D2 groups. However, tests of trend were significant for onset time (p<0.001), thereby suggesting a dose-dependent increase in the observed effect over the three doses of dexmedetomidine. Compared with its D0 counterpart, the D2 group displayed a longer mean duration of motor block (26.4 (6.6) vs 23.0 (4.9) hours; p=0.030). No other differences in analgesic or block duration were found among the three groups. The incidences of surgical anesthesia (97.1–100%) and adverse events were similar for all three groups. Conclusion: Compared with control (dexmedetomidine 0 µg/kg), perineural dexmedetomidine 0.67 µg/kg and 1.33 µg/kg decrease the onset time of bupivacaine 0.5%–epinephrine (5 µg/mL)–perineural dexamethasone (4 mg) for US-guided ICBs. Although no intergroup differences in onset were found between the 0.67 µg/kg and 1.33 µg/kg doses, there was a statistically significant directional trend, which suggested a possible dose-dependent effect. Future trials are also required to determine the optimal dose of perineural dexmedetomidine.

Background: Excessive gingival display, or “gummy smile,” occurs in up to 14% of adults and is associated with lip hyperactivity, dentoalveolar extrusion, or vertical maxillary excess. Botulinum toxin A (BTA) has emerged as a minimally invasive therapeutic option, but protocols vary widely and long-term data are limited. Objectives: To critically evaluate the current literature on BTA in gummy smile management, focusing on classification systems, injection techniques, efficacy, safety, and comparative outcomes against conventional surgical and orthodontic treatments. Methods: A narrative review was performed using PubMed, MEDLINE, and Scopus (2000-2023) with the terms “gummy smile,” “excessive gingival display,” and “botulinum toxin.” Clinical studies, case series, and reviews addressing BTA use were included. Data were synthesized into thematic categories. Results: BTA consistently reduced gingival exposure by 3 to 5 mm, with effects lasting 4 to 6 months. Three main injection strategies were identified: single-point (Yonsei), multi-point, and orbicularis oris (“lip flip”). Reported complications were rare and transient (mild asymmetry, lip weakness). Standardized protocols were lacking, with heterogeneity in dosing (2-5 units per site) and injection depth. Comparative studies suggested BTA is less durable than surgical approaches but offers superior patient acceptability and safety for mild to moderate cases. Conclusion: BTA provides reproducible, temporary improvement in gummy smiles with high safety and satisfaction rates. However, absence of consensus on optimal technique and limited long-term evidence highlight the need for standardized protocols and prospective multicenter studies.

Background This randomized trial compared ultrasound-guided interscalene block (ISB) and combined infraclavicular (ICB)-anterior suprascapular nerve block (SSNB) for arthroscopic shoulder surgery. We hypothesized that combined ICB-anterior SSNB provides equivalent analgesia to ISB 30 min after surgery. Methods Fifty subjects were randomized to ISB or combined ICB-anterior SSNB. Twenty mL of bupivacaine 0.5% with epinephrine 5 µg/mL was used for ISB. For ICB and anterior SSNB, we administered 20 mL and 3 mL of bupivacaine 0.5% with epinephrine 5 µg/mL, respectively. Subsequently, all patients underwent general anesthesia. The primary outcome was the pain score at 30 min in the post-anesthesia care unit. Secondary outcomes included the rate of complete sensorimotor blockade (assessed after the performance of the blocks using a 14-point composite scale), postoperative pain scores at 0.5, 1, 3, 6, 12, 24, 36, and 48 hours, the presence of hemidiaphragmatic paralysis at 30 min after the performance of the blocks and in the post-anesthesia care unit, consumption of intraoperative and postoperative narcotics, opioid-related side effects, and patient satisfaction at 24 hours. Results No intergroup differences were found in postoperative pain scores, proportion of patients with complete sensorimotor blockade, intraoperative/postoperative opioid consumption, side effects, and patient satisfaction at 24 hours. Compared with combined ICB-SSNB, ISB resulted in a higher incidence of hemidiaphragmatic paralysis 30 min after the block and in the post-anesthesia care unit (68% vs 0%; and 88% vs 0%, respectively; both pConclusion Compared with ISB, combined ICB-anterior SSNB results in equivalent postoperative analgesia while circumventing the risk of hemidiaphragmatic paralysis. Further confirmatory trials are required. Future studies should also investigate whether combined ICB- anterior SSNB can provide surgical anesthesia for shoulder surgery. Trial registration number NCT05444517.

Primary failure of thoracic epidural analgesia (TEA) remains an important clinical problem, whose incidence can exceed 20% in teaching centers. Since loss-of-resistance (LOR) constitutes the most popular method to identify the thoracic epidural space, the etiology of primary TEA failure can often be attributed to LOR’s low specificity. Interspinous ligamentous cysts, non-fused ligamenta flava, paravertebral muscles, intermuscular planes, and thoracic paravertebral spaces can all result in non-epidural LORs. Fluoroscopy, epidural waveform analysis, electrical stimulation, and ultrasonography have been proposed as confirmatory modalities for LOR. The current evidence derived from randomized trials suggests that fluoroscopy, epidural waveform analysis, and possibly electrical stimulation, could decrease the primary TEA failure to 2%. In contrast, preprocedural ultrasound scanning provides no incremental benefit when compared with conventional LOR. In the hands of experienced operators, real-time ultrasound guidance of the epidural needle has been demonstrated to provide comparable efficacy and efficiency to fluoroscopy. Further research is required to determine the most cost-effective confirmatory modality as well as the best adjuncts for novice operators and for patients with challenging anatomy. Moreover, future trials should elucidate if fluoroscopy and electrical stimulation could potentially decrease the secondary failure rate of TEA, and if a combination of confirmatory modalities could outperform individual ones.

Background This cadaveric study investigated the maximum effective volume of dye in 90% of cases (MEV90) required to stain the iliac bone between the anterior inferior iliac spine (AIIS) and the iliopubic eminence (IPE) while sparing the femoral nerve during the performance of pericapsular nerve group (PENG) block. Methods In cadaveric hemipelvis specimens, the ultrasound transducer was placed in a transverse orientation, medial and caudal to the anterior superior iliac spine in order to identify the AIIS, the IPE and the psoas tendon. Using an in-plane technique and a lateral-to-medial direction, the block needle was advanced until its tip contacted the iliac bone. The dye (0.1% methylene blue) was injected between the periosteum and psoas tendon. Successful femoral-sparing PENG block was defined as the non-staining of the femoral nerve on dissection. Volume assignment was carried out using a biased coin design, whereby the volume of dye administered to each cadaveric specimen depended on the response of the previous one. In case of failure (ie, stained femoral nerve), the next one received a lower volume (defined as the previous volume with a decrement of 2 mL). If the previous cadaveric specimen had a successful block (ie, non-stained femoral nerve), the next one was randomized to a higher volume (defined as the previous volume with an increment of 2 mL), with a probability of b=1/9, or the same volume, with a probability of 1–b=8/9. Results A total of 32 cadavers (54 cadaveric hemipelvis specimens) were included in the study. Using isotonic regression and bootstrap CI, the MEV90 for femoral-sparing PENG block was estimated to be 13.2 mL (95% CI: 12.0 to 20.0). The probability of a successful response was estimated to be 0.93 (95% CI: 0.81 to 1.00). Conclusion For PENG block, the MEV90 of methylene blue required to spare the femoral nerve in a cadaveric model is 13.2 mL. Further studies are required to correlate this finding with the MEV90 of local anesthetic in live subjects.