No abstract

A continuous adductor canal block for total knee arthroplasty reduces opioid consumption compared with that of placebo in the first 48 hours after surgery. Other outcomes including quadriceps strength, distance ambulated, and pain scores all show benefit from an adductor canal catheter after total knee arthroplasty but require further study before being interpreted as conclusive.

Background The interscalene nerve block provides analgesia for shoulder surgery, but is associated with diaphragm paralysis. One solution may be performing brachial plexus blocks more distally. This noninferiority study evaluated analgesia for blocks at the supraclavicular and anterior suprascapular levels, comparing them individually to the interscalene approach. Methods One hundred-eighty-nine subjects undergoing arthroscopic shoulder surgery were recruited to this double-blind trial and randomized to interscalene, supraclavicular, or anterior suprascapular block using 15 ml, 0.5% ropivacaine. The primary outcome was numeric rating scale pain scores analyzed using noninferiority testing. The predefined noninferiority margin was one point on the 11-point pain scale. Secondary outcomes included opioid consumption and pulmonary assessments. Results All subjects completed the study through the primary outcome analysis. Mean pain after surgery was: interscalene = 1.9 (95% CI, 1.3 to 2.5), supraclavicular = 2.3 (1.7 to 2.9), suprascapular = 2.0 (1.4 to 2.6). The primary outcome, mean pain score difference of supraclavicular–interscalene was 0.4 (–0.4 to 1.2; P = 0.088 for noninferiority) and of suprascapular–interscalene was 0.1 (–0.7 to 0.9; P = 0.012 for noninferiority). Secondary outcomes showed similar opioid consumption with better preservation of vital capacity in the anterior suprascapular group (90% baseline [P < 0.001]) and the supraclavicular group (76% [P = 0.002]) when compared to the interscalene group (67%). Conclusions The anterior suprascapular block, but not the supraclavicular, provides noninferior analgesia compared to the interscalene approach for major arthroscopic shoulder surgery. Pulmonary function is best preserved with the anterior suprascapular nerve block.

Purpose The saphenous nerve block using a landmarkbased approach has shown promise in reducing postoperative pain in patients undergoing arthroscopic medial meniscectomy. We hypothesized that performing an ultrasound-guided adductor canal saphenous block as part of a multimodal analgesic regimen would result in improved analgesia after arthroscopic medial meniscectomy. Methods Fifty patients presenting for ambulatory arthroscopic medial meniscectomy under general anesthesia were prospectively randomized to receive an ultrasoundguided adductor canal block with 0.5% ropivacaine or a sham subcutaneous injection of sterile saline. Our primary outcome was resting pain scores (numerical rating scale; NRS) upon arrival to the postanesthesia care unit (PACU). Secondary outcomes included NRS at six hours, 12 hr, 18 hr, and 24 hr; postoperative nausea; and postoperative opioid consumption.Results There was a statistically significant difference in mean NRS pain scores upon arrival to the PACU (P = 0.03): block group NRS = 1.71 (95% confidence interval [CI] 0.73 to 2.68) vs sham group NRS = 3.25 (95% CI 2.27 to 4.23). Cumulative opioid consumption (represented in oral morphine equivalents) over 24 hr was 71.8 mg (95% CI 56.5 to 87.2) in the sham group vs 44.9 mg (95% CI 29.5 to 60.2) in the block group (P = 0.016). Conclusions An ultrasound-guided block at the adductor canal as part of a combined multimodal analgesic regimen significantly reduces resting pain scores in the PACU following arthroscopic medial meniscectomy. Furthermore, 24-hr postoperative opioid consumption and pain scores were also reduced. RésuméObjectif Le bloc du nerf saphène à l'aide d'une approche par repères anatomiques s'est avéré prometteur pour réduire la douleur postopératoire chez les patients subissant une méniscectomie médiale par arthroscopie. Nous avons émis l'hypothèse qu'en réalisant un bloc échoguidé du canal adducteur du nerf saphène dans le cadre d'un régime analgésique multimodal, l'analgésie serait plus efficace après une méniscectomie médiale par arthroscopie. Méthode Cinquante patients devant subir une méniscectomie médiale par arthroscopie en ambulatoire sous anesthésie générale ont été randomisés de façon prospective à recevoir un bloc échoguidé du canal adducteur avec de la ropivacaïne 0,5 % ou une injection sous-cutanée fictive de solution saline stérile. Notre critère d'évaluation principal était les scores de douleur au repos (échelle d'évaluation numérique; É É N) à l'arrivée en salle de réveil. Les critères d'évaluation secondaires comprenaient l'É É N à six heures, 12 h, 18 h et 24 h; les nausées Author contributions Neil A. Hanson and Francis V. Salinas were involved in the study design.

The objective of this study was to evaluate an injectable, in situ crosslinkable elastin-like polypeptide (ELP) gel for application to cartilage matrix repair in critically sized defects in goat knees. One cylindrical, osteochondral defect in each of seven animals was filled with an aqueous solution of ELP and a biocompatible, chemical crosslinker, while the contralateral defect remained unfilled and served as an internal control. Joints were sacrificed at 3 (n = 3) or 6 (n = 4) months for MRI, histological, and gross evaluation of features of biomaterial performance, including integration, cellular infiltration, surrounding matrix quality, and new matrix in the defect. At 3 months, ELP-filled defects scored significantly higher for integration by histological and gross grading compared to unfilled defects. ELP did not impede cell infiltration but appeared to be partly degraded. At 6 months, new matrix in unfilled defects outpaced that in ELP-filled defects and scored significantly better for MRI evidence of adverse changes, as well as integration and proteoglycan-containing matrix via gross and histological grading. The ELP-crosslinker solution was easily delivered and formed stable, well-integrated gels that supported cell infiltration and matrix synthesis; however, rapid degradation suggests that ELP formulation modifications should be optimized for longer-term benefits in cartilage repair applications.