Joints of the Shoulder Girdle:

  • The sternoclavicular joint - where the sternum meets the proximal end of the clavicle.
    • Etymology:
      • Sternum - "breastbone," 1660s, from Greek sternon "chest, breast, breastbone" (in Homer, only of males), also "the breast as the seat of affections," related to stornynai "to spread out," from PIE *ster-no- "to stretch, extend," from root *stere-, *ster- "to spread," related to stornynai "to spread out" (see structure (n.)), on the notion of the chest as broad and flat, as opposed to the neck. Related: Sternal. (Etymology Dictionary)
      • Clavicle - Etymology: L, clavicula, little key (Medical Dictionary)

Sternoclavicular Joint

Sternoclavicular Joint - By Henry Vandyke Carter - Henry Gray (1918) Anatomy of the Human Body (See "Book" section below) Gray's Anatomy, Plate 325, Public Domain,

  • The acromioclavicular joint - where the acromion of the scapula meets the distal end of the clavicle
    • Etymology:

Acromioclavicular (AC) Joint

Acromioclavicular Joint (AC Joint) - By Henry Vandyke