Superior Trunk Block: Ultrasound Guided Novel Approach for Shoulder Surgery

The use of ultrasound in clinical anaesthesia has largely contributed to the development of the nerve block technique in recent years. In the standard ultrasound-guided interscalene brachial plexus block, the C5 and C6 nerve roots are directly infiltrated. Hemi diaphragmatic paresis almost usually follows arthroscopic shoulder surgery, despite the fact that it offers highly effective postoperative analgesia [1]. Other issues include the potential for intraneural injection into the relatively exposed roots as well as damage to the long thoracic nerve or dorsal scapular nerve [2]. Burckett-St. Laurent, et al. [3] described the superior trunk block as a development of the traditional interscalene block technique that addresses these drawbacks. Since the C5 and C6 nerve roots fuse to form the superior trunk, local anaesthetic injections around the superior trunk should have a similar effect on the shoulder’s analgesia because all of the terminal nerves that innervate the shoulder originate distal to the superior trunk. Additionally, because the injection site is farther from the phrenic nerve, there should be less chance of hemi diaphragmatic paresis [4].