Sensory innervation of the human shoulder joint: the three bridges to break.J Shoulder Elbow Surg. 2020 Jul 23 [Online ahead of print]JS
Painful shoulders (PS) create a substantial socioeconomic burden and significant diagnostic challenge for shoulder surgeons. Consensus with respect to the anatomic location of sensory nerve branches is lacking. The aim of this literature review was to establish consensus with respect to the anatomic features of the articular branches (AB) (1) innervating the shoulder joint, and (2) the distribution of sensory receptors about its capsule and bursae.
MATERIALS & METHODS
Four electronic databases were queried, between January 1945 and June 2019. Thirty original articles providing a detailed description of the distribution of sensory receptors about the shoulder joint capsule (13) and its articular branches (22) were reviewed.
The suprascapular, lateral pectoral, axillary, and lower subscapular nerves were found to provide AB to the shoulder joint. The highest density of nociceptors was found in the sub-acromial bursa. The highest density of mechanoreceptors was identified within the insertion of the glenohumeral ligaments. The most frequently identified innervation pattern was comprised of three nerve bridges (consisting of AB from suprascapular, axillary, and lateral pectoral nerves) connecting the trigger and the identified pain generators areas rich in nociceptors.
Current literature supports the presence of a common sensory innervation pattern for the human shoulder joint. Anatomic studies have demonstrated that the most common parent nerves supplying AB to the shoulder joint are the suprascapular, lateral pectoral, and axillary nerves. Further studies are needed to assess both the safety and efficacy of selective denervation of the PS, while limiting the loss of proprioceptive function.
LEVEL OF EVIDENCE
Anatomy Study; Literature Review.