Levator scapulae and rhomboid minor are united

Abstract

Pain over the superior angle of the scapula is a common musculoskeletal symptom. It is often accompanied by radiating pain to the neck, head, and shoulder. The aetiologies can be varied but may also be idiopathic in nature. To explore the fascial connections of this region, we studied 26 unembalmed, -two Thiel and one alcohol body-donors of science, by dissection, histological probes, and plastinations. When removing the descending and transverse fibres of the trapezius, a large prominent triangular area of white connectives is revealed, varying in mass. A subdivision of these connectives can be further dissected to prove that the rhomboid minor and levator scapulae muscles are interconnected and enclosed by connectives. Between these two muscles a bridge of connective tissue, containing fat, is observed. These connectives end cranially at the surface of the splenius capitis, and at the midline, containing vessels and nerves, as supported by histology and plastinations. This unification is separate from the rhomboid major muscle but overlaps with the latter dorsally. It connects to the superior angle of scapula and its upper medial borders, respectively, and cranially to the root of the spine of the scapula. Beneath the united levator scapulae and rhomboid minor, described here, the serratus posterior superior and possibly serratus anterior form a hypomochlion or fulcrum at the superior angle of the scapula. Any tension on this unified entity can unbalance this fulcrum. Investigating the connections between these two unified muscles may help explain the often idiopathic nature of superior scapular pain, and the success or failure of surgery, and other treatments.

Keywords: Cervical fascia; Levator scapulae; Myofascial pain; Neck fascia; Rhomboid minor; Scapula pain; Trigger points.