[header] How to splint a humerus fracture [title] Identify a proximal humerus fracture. [step] This type of injury can cause damage to the ball and socket (glenohumeral) joint where the humerus bone attaches to the shoulder girdle. A fracture in this location causes difficulty with shoulder movement, such as trying to raise the arm overhead. 
Palpate (touch) the upper arm and feel for any bumps, lumps or evidence of broken skin. Carefully remove or alter clothing so you can see the entire arm and look for signs of bruising, inflammation or deformity.