Background: The suprascapular nerve is largely responsible for the majority of the sensory innervation of the acromioclavicular joint. In this anatomical study, we describe, in detail, the anatomy of the sensory innervation of the acromioclavicular joint by the branches of the suprascapular nerve.
Methods: Twenty-seven shoulders from 17 cadaveric specimens were carefully dissected to identify the course of the suprascapular nerve, with the main focus being on the sensory innervation of the acromioclavicular joint. Nine specific measurements of the acromioclavicular joint sensory nerves were made of each shoulder in relation to distinct anatomical landmarks to determine the mean location and course of these nerves.
Results: In all 27 shoulders (100%), a sensory branch to the acromioclavicular joint with a proximal origin from the suprascapular nerve could be depicted ("first sensory branch"). The mean length of this branch was 4.3 cm (range: 3.3-5.3 cm). In 14 shoulders (52%), a further sensory branch of the suprascapular nerve innervating the posterior acromioclavicular joint capsule could be identified ("second sensory branch").
Discussion: A detailed anatomical description of the sensory innervation of the acromioclavicular joint from suprascapular nerve branches was performed, which can potentially aid in the development of more focused anesthetic blockades and acromioclavicular joint denervation procedures.
Keywords: acromioclavicular joint; anatomy; joint innervation; shoulder surgery; suprascapular nerve.
© 2019 The British Elbow & Shoulder Society.