Myofascial chains of the upper limb: A systematic review of anatomical studies.

The presence of structural in-series continuity between skeletal muscles has been confirmed in the trunk and lower extremity. However, it is not yet clear whether the same architecture can be found in the upper limb. Therefore, the aim of the present study was to review the available literature considering the existence of myofascial chains in the shoulder-arm region. Two independent investigators performed a systematic literature search using MEDLINE (PubMed) and Google Scholar (each 1900-2019). Peer-reviewed anatomical dissection studies reporting myofascial in-series continuity in the upper extremity were included. The methodological quality of the included studies was assessed by the QUACS scale. Thirteen studies were included in the review. Analysis of these papers led to the identification of three myofascial chains: the ventral arm chain (pectoralis major, brachial fascia/biceps brachii, flexor carpi ulnaris/brachioradialis/supinator, based on five studies); the lateral arm chain (trapezius, deltoideus, lateral intermuscular septum/brachialis, brachioradialis, four studies); and the dorsal arm chain (latissiumus dorsi/teres minor/infraspinatus, triceps brachii, anconeus, extensor carpi ulnaris, six studies). There is good evidence for direct serial tissue continuity extending from the neck and shoulder region to the forearm. Despite this intriguing finding, which could have implications for health professionals and the treatment of musculoskeletal disorders, further research is needed to establish the mechanical relevance of the identified myofascial chains. Clin. Anat. 32:934-940, 2019.