Anatomical study of the superficial cervical plexus targeted for sensory nerve blocks in neonates

The superficial cervical plexus block can be used to provide perioperative analgesia in pediatric patients undergoing thyroid surgeries, brachial cleft cyst excision, tympano-mastoid surgery, as well as cochlear implantation. The cervical plexus is formed by the first four cervical spinal nerves, and the superficial cutaneous branches emerge from the posterior border of the sternocleidomastoid muscle, often referred to as the "nerve point of the neck." The aims of this study were to evaluate the location of this nerve point and formulate a standardized method of blocking the superficial cervical plexus in pediatric patients.

The nerve point of the neck and the superficial branches of the cervical plexus were dissected and exposed on 22 neonatal cadavers from the Department of Anatomy, University of Pretoria, after ethical clearance was obtained. The distances between the nerve point and predetermined landmarks were calculated.

The nerve point was located 17.51 mm from the sternocleidomastoid muscle attachment at the rudimentary mastoid process and 19.80 mm from the clavicular attachment of the muscle. The nerve point is approximately 20.99 mm from the midline of the neck, and the superior border of the thyroid cartilage corresponds to the level of the nerve point in 83.3% of neonatal dissections.

The superficial cervical plexus can be blocked along the midpoint of the posterior border of the sternocleidomastoid muscle, at the level of the superior border of the thyroid cartilage. This research will assist in the successful performance of sensory nerve blocks in pediatric patients.