The anatomy of the supraclavicular nerve during surgical approach to the clavicular shaft

Background: Surgery for clavicular shaft fractures is becoming more common but incisional and chest wall numbness reportedly occurs in 10% to 29% of patients. This may be the result of iatrogenic injury to the supraclavicular nerve branches. Questions/purposes: We determined if there was a predictable branching pattern of the supraclavicular nerve at the anterior clavicular border and determined the distances to these nerves from clavicular landmarks. Methods: We performed an anatomic dissection along the anterior border of the long axis of the clavicle in 37 cadavers. The branches of the supraclavicular nerve were identified at the anterosuperior clavicular border and the distances from these nerves to palpable bony landmarks were measured. Results: Ninety-seven percent of specimens had a medial and a lateral branch of the supraclavicular nerve. Nearly half (49%) possessed an additional intermediate branch. No branch was found within 2.7 cm of the sternoclavicular joint or within 1.9 cm of the acromioclavicular joint. Between these two positions, there was wide variability in nerve branch location. Conclusions: There were two or three branches of the supraclavicular nerve crossing the clavicle 97% of the time and a wide variability of the location of these branches outside the safe zones. Clinical Relevance: There are safe zones within 2.7 cm of the sternoclavicular joint and 1.9 cm of the acromioclavicular joint. Between these safe zones, the location of the nerve branches is variable and the surgeon must use meticulous dissection if he or she wishes to prevent transection.