Fig. 1.

Deltoid overview. (A) (Specimen S3) Anterior deltoid (d) and pectoralis major. cl: clavicle. at: anterior deltoid ET blade. pc, pt: clavicular and thoracic parts of pectoralis major. ch: chiasma of vena cephalica. br: brachialis (biceps has been removed). cb: coracobrachialis. (B) (specimen S5) Posterior deltoid. sp: spina scapula (the supra-spinal scapula was covered by black background). ps: posterior spinal deltoid segment, mobilized from anterior spinal deltoid (as). ac: acromial deltoid. if: infraspinal fascia, covering infraspinatus and spinal deltoid OT sheet. White dotted line: origin line of spinal deltoid OT. Black dotted line: posterior deltoid edge. (C) Cross-section through humerus heads (h), left and right shoulders (from: ‘Visible Human’). Top is posterior. Deltoid (d) transected just beneath spina scapula, showing the great origin width compared to humerus width. White dotted line: outline of deltoid in right shoulder; left shoulder was left unmarked. s: scapula. i: infraspinatus. su: subscapularis.