Transhumeral Trimlines

Trimlines vary, depending on the level of amputation and the activity level

• Type I Elbow Disarticulation
  • Axilla trimline: high enough for socket stability
  • Anterior trimline: encompass the humerus in its entirety, but does not impede ROM
  • Superior/lateral: 1-2cm (½”) proximal to the level of the axilla or at level of axilla
  • Posterior: encompass the humerus in its entirety
• Type II Medium-long transhumeral
  • Axilla trimline: at pectoralis and teres tendon/muscle
  • Anterior trimline: fossa-shaped, deepest portion of deltopectoral groove is medial to the apex of the head of the humerus and about 3-5cm (1-2”) inferior to the clavicle, does not extend to sternum.
  • Superior/lateral: 3-5cm (1½-2”) proximal to the level of the axilla
  • Posterior: extends over the scapula for socket stability, below the spine of the scapula, does not pass medial border of scapula
• Type III Short Transhumeral
  • Axilla trimline: pectoralis and teres tendons/muscles in contact with the socket, extensions down three ribs on the chest wall.
  • Anterior trimline: prevent edge pressure; does not impede ROM.
    • Short Transhumeral: medial to the delto pectoral groove
  • Superior/lateral: 3-5cm (1½-2”) proximal to the level of the axilla
  • Posterior: include as much of the scapula as possible