Selective blockade of the dorsal scapular nerve for scapula surgery

Selective Dorsal Scapular Nerve and Long Thoracic Nerve Blocks for Rescue Analgesia in Scapulothoracic Arthrodesis Surgery: A Case Report

Scapulothoracic arthrodesis (STA) surgery is performed to stabilize the scapula in patients with facioscapulohumeral dystrophy (FSHD). Postoperative pain could be a major problem even while using erector spinae plane block (ESPB). We performed a preoperative ESPB with an intraoperative ESPB catheter, but rescue analgesia was needed for pain in the periscapular area in the postoperative period. The patient's pain score was reduced by applying an ultrasound-guided dorsal scapular nerve (DSN) and long thoracic nerve (LTN) block. Selective DSN and LTN blocks can be effective in enhancing postoperative analgesia in STA surgery.

Utilizing an ultrasound guided 5-in-1 trigger point and hydrodissection technique for interscapular mid-thoracic myofascial pain: A retrospective review

Poor posture can lead to excessive strain of the neck and upper back musculature, leading to irritation of the dorsal scapular nerve (DSN) and spinal accessory nerve (SAN). A 5-in-1 trigger point technique has been described that specifically target trapezius, rhomboids, levator scapulae, SAN and DSN in a single percutaneous injection. We modified the technique to include hydrodissecting the DSN and SAN to provide further pain relief from possible nerve entrapments. Our retrospective review revealed that the modified 5-in-1 technique is a safe and effective way to address medial periscapular pain, often seen with anterior head carriage and upper crossed syndrome. Patients who received the modified 5-in-1 technique had statistically significant pain relief, allowing them to participate in rehabilitation programs.

Single continuous erector spinae plane block for multiple rib, clavicle, and scapula fractures: A case report

The aim of this study is to describe the ability of a continuous erector spinae plane (ESP) block to provide analgesia in an extended territory (brachial plexus and thoracic nerves) with a single catheter. A continuous ESP block at T4 was performed in a 74-year-old man, two days after trauma involving clavicle, scapula, and multiple posterior rib fractures (first to ninth). The technique was maintained for 12 days and provided effective analgesia not only to the thoracic region but also the scapula and clavicle area (C5–T12 dermatomes). Concomitant respiratory insufficiency was ameliorated, which helped to avoid mechanical ventilation and intensive care unit admission. Moreover, this analgesia technique promoted patient's ambulation. ESP block, as an alternative to a thoracic epidural, is a more straightforward and safer procedure than paravertebral block (PVB). To obtain an extensive dermatome block using PVB, more than one paravertebral catheter would be necessary. Extensive cephalad–caudad spread of the PVB is primarily related to analgesia due to the concomitant epidural spread. PVB frequently causes bilateral block and may produce significant motor or sympathetic block. Additionally, proximal extension of the block under the erector spinae muscle fascia can provide a significant extension of the block to the cervical region, which allows brachial plexus block (cervical plexus block was not observed clinically). This is a unique feature of ESP block, as there is no communication between adjacent paravertebral levels in the cervical region that could allow the same pattern of analgesia using PVB.

Scapular Block: An Innovative Procedure-Specific Regional Anesthesia Technique for Scapula Surgery-A Case Report

A 40-year-old healthy male patient underwent open reduction and internal fixation with screws and plate for a comminuted fracture of the right scapula under ultrasound-guided "scapular block" with optimal sedation. We coined the term "scapular block" for an innovative combination of previously described regional anesthesia techniques to cover all dermatomes, myotomes, and osteotomes involved in scapula surgery. It is a combination of 5 target blocks (selective superior trunk block, selective supraclavicular nerve block, subclavian perivascular block, suprascapular nerve block, and erector spinae plane block) via 3 approaches (interscalene, supraclavicular, and paraspinal).

Regional anesthesia for scapular fracture surgery: an educational review of anatomy and techniques

Scapular fractures are very rare, and those requiring surgical interventions are even rarer. Most scapula surgeries are done under general anesthesia with or without the regional anesthesia (RA) technique as an adjunct. Since scapular innervation is complicated, a thorough review of the relevant anatomy is warranted. In this RAPM educational article, we aimed to summarize the target nerves and blocks needed to optimize analgesia or even to provide surgical anesthesia for scapula surgeries. In this review, we are describing an algorithmic "identify-select-combine" approach, which enables the anesthesiologist to understand detailed innervation of the scapula and to obtain a procedure-specific RA technique. Procedure-specific RA would probably be the way forward for defining future RA practices.

New insights into pathways of the dorsal scapular nerve and artery for selective dorsal scapular nerve blockade

Background

The aim of this study was to clarify the topographical relationships between the dorsal scapular nerve (DSN) and the dorsal scapular artery (DSA) in the interscapular region to identify safe and convenient injection points related to DSN blockade.

Methods

Thirty shoulders of embalmed Korean cadavers and 50 live subjects were used for dissection and ultrasound (US) analysis.

Results

The running patterns of the DSA and DSN in the interscapular region were classified into 3 types. Type I was defined as nerves that were medial to the artery and parallel without changing location (80.0% of specimens). In type II (13.3%), the nerve and artery traversed one another only one time over their entire length. In type III (6.7%), the nerve and artery traversed one another, resembling a twist. Above the level of the scapular spine, the nerve was always medial to the artery. Below the scapular spine, the number of arteries was obviously decreased. Most of the arteries were lateral to the medial border of the scapula, except at the level of the superior angle of the scapula artery (SA). The positional tendency of the DSN toward the medial or lateral sides from the medial border of the scapula was similar. In US imaging of live subjects, the DSA was most observed at the level of the SA (94.0%).

Conclusions

Results of this study enhance the current knowledge regarding the pathway of the DSN and DSA and provide helpful information for selective diagnostic nerve blocks in the interscapular region.

The Effect of Fixation Technique on Continuous Interscalene Nerve Block Catheter Success: A Randomized, Double-Blind Trial

BACKGROUND

Continuous peripheral nerve blocks offer advantages over single-injection blocks, including extended analgesia and reduction in opioid consumption. These benefits require that the perineural catheter remain intact for the duration of the planned local anesthetic infusion. Mechanical displacement of catheters, leaking, and consequent failure are known complications. The aim of this study was to evaluate continuous perineural catheter tip-to-nerve apposition in vivo over 48 hours comparing 2 different simple fixation strategies.

METHODS

Subjects presenting for a continuous interscalene nerve block were randomized to perineural catheter fixation with 1 of 2 types of adhesive: Dermabond (2-octylcyanoacrylate) or Mastisol (alcohol 23A, gum mastic, storax, and methyl salicylate), covered with a simple transparent dressing. The primary outcome was the evaluation of catheter-to-nerve apposition maintenance over 48 hours via both a blinded ultrasound evaluation of local anesthetic distribution and a blinded clinical assessment. Secondary outcomes included leakage at the catheter site, pain scores, opioid consumption, catheter-to-skin migration at the insertion site, and patient satisfaction.

RESULTS

Sixty-six subjects were recruited and randomized to compare adhesive group catheter tip-to-nerve apposition on postoperative day 2 (POD 2). Within the intention-to-treat cohort, a statistically significant decrease of perineural catheter tip-to-nerve apposition in the Mastisol group (64.7%) compared with the Dermabond group (90.6%) on POD 2 (odds ratios [OR] 0.19; 95% confidence interval [CI] 0.05-0.75; P = .012) was observed. Similar results were observed on POD 1 (OR 0.19; 95% CI 0.03-1.38; P = NS) and POD 2 (OR 0.14; 95% CI 0.02-0.97; P = .008) within the as-treated cohort. Catheter leakage (OR 67; 95% CI 7.3-589) and median catheter migration difference at the skin insertion site (2.0 cm; 95% CI 0.5-2.5) were also significantly greater in the Mastisol group than in the Dermabond group from POD 0 to POD 2 (P < .001). Median postoperative opioid consumption difference in morphine equivalents (3.2 mg; 95% CI - 9.0 to 14.2) was not significantly different between the Dermabond and the Mastisol groups through POD 2 (P = .542).

CONCLUSIONS

Perineural catheter fixation with Dermabond in continuous interscalene nerve block improves maintenance of catheter-to-nerve apposition when compared with Mastisol.

A Cadaveric Investigation of the Dorsal Scapular Nerve

Compression of the dorsal scapular nerve (DSN) is associated with pain in the upper extremity and back. Even though entrapment of the DSN within the middle scalene muscle is typically the primary cause of pain, it is still easily missed during diagnosis. The purpose of this study was to document the DSN's anatomy and measure the oblique course it takes with regard to the middle scalene muscle. From 20 embalmed adult cadavers, 23 DSNs were documented regarding the nerve's spinal root origin, anatomical route, and muscular innervations. A transverse plane through the laryngeal prominence was established to measure the distance of the DSN from this plane as it enters, crosses, and exits the middle scalene muscle. Approximately 70% of the DSNs originated from C5, with 74% piercing the middle scalene muscle. About 48% of the DSNs supplied the levator scapulae muscle only and 52% innervated both the levator scapulae and rhomboid muscles. The average distances from a transverse plane at the laryngeal prominence where the DSN entered, crossed, and exited the middle scalene muscle were 1.50 cm, 1.79 cm, and 2.08 cm, respectively. Our goal is to help improve clinicians' ability to locate the site of DSN entrapment so that appropriate management can be implemented.