Humeral Head Anatomy

proximal humerus medial picture

rotator cuff insertion picture

Humeral Head Anatomy

  • Humeral head radius averages 23mm (17-28mm) (Robertson DD, JBJS 2000;82A:1594)
  • Humeral head thickness averages 19mm (15-24mm) (Robertson DD, JBJS 2000;82A:1594)
  • The center of the humeral head is offset 7mm medially and 2mm posteriorly relative to the humeral axis. (Robertson DD, JBJS 2000;82A:1594)
  • Humeral head inclination averages 41 degress. (Robertson DD, JBJS 2000;82A:1594)
  • Neck-shaft angle averages 131 degrees. (Robertson DD, JBJS 2000;82A:1594)
  • Proximal humeral retroversion averages 19 degrees, but is variable (9 to 31 degrees)
  • Superior articular surface of the humeral head is usually 8-10mm superior to the highest point of the greater tuberosity.
  • Blood Supply: main source is the anterolateral (arcuate) branch of the anterior humeral circumflex artery, which runs under the long head of the biceps tendon and then adjacent to the lateral aspect of the intertubercular groove. It enters the humeral head at ehr proximal end of the transition from the greater tuberosity to the intertubercular groove. (Gerber C, JBJS 1990;72A:1486)