Subscapularis Plane Block ‐ A Novel Phrenic Nerve Sparing Single Injection Shoulder Block ‐ An Anatomical Study
Notice bibliographique
Résumé
Introduction The interscalene block (ISB) is the gold standard regional anesthetic for shoulder surgery, but invariably results in ipsilateral hemi‐diaphragmatic paralysis due to phrenic nerve involvement. Isolated blocks targeting the suprascapular and axillary nerves separately have been shown to be less effective than the gold standard. The specific aim of this study was to develop a novel peripheral block for shoulder surgeries that would avoid phrenic nerve involvement and associated hemi‐diaphragm paralysis, while still providing adequate anesthesia of the targeted nerves to provide a suitable alternative to the gold standard. It was hypothesized that a subscapularis plane block (SPB), as a single injection, would provide a novel technique to block the suprascapular nerve, axillary nerve, and the upper and lower subscapular nerves. Methodology Bilateral, ultrasound‐guided (Sonosite M‐Turbo) SPB blocks were performed with a linear probe (13‐6 MHz) on 4 fresh cadavers (n = 8) using 5% dextrose with methylene blue dye as injectate (2 – 10 mLs). With the transducer aligned in the sagittal plane and moving medially, first the head of the humerus was identified, then the bicipital groove, then the coracoid process. Medial to the coracoid process, from superior to inferior, the skin, subcutaneous tissue, deltoid, pectoralis major, pectoralis minor, subscapularis muscles, and subscapular fossa were identified. An insulated Tuohy needle (17 gauge × 80 mm) was used to deposit the injectate above the fascia of the subscapularis muscle. Each cadaver was dissected to note the spread of injectate. The first set of 4 blocks were performed to determine the location of the block, while the second set of 4 blocks were performed to replicate the successful block and standardize the volume used. Results Overall, 37.5% of the blocks (3/8) performed were successful in staining all of the target nerves. 37.5% of the blocks (3/8) performed resulted in the injectate spreading along the axillary sheath into the axilla, staining the posterior cord and the lateral cord, but not the suprascapular nerve. 25% of the blocks (2/8) performed resulted in the injectate spreading deep to the subscapularis fascia into the joint. 100% of the blocks spared the phrenic nerve. Discussion The angle of the needle appears to factor into the success of the block, as the injectate spread into the axilla when angled more laterally instead of perpendicular to the injection site. Ultrasound visualization of the subscapularis plane in cadavers also contributed to the blocks success rate, as the needle was sometimes inserted deep to the subscapularis fascia, resulting in spread of the injectate to the joint capsule. A single injection, phrenic nerve sparing SPB may be a viable alternative to the gold standard for shoulder surgery anesthetic management. A clinical trial is currently underway to establish the efficacy of the SPB compared to the ISB.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,003 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».