Elbow doesn't sit right. if arms extend straight palms flat iner elbow faces up. no trama. just noticed when stretching. no pain. stiff movement.

Hyper extension: Hyperextension of the elbow in a young female suggests joint hypermobility syndrome (jhs). Other signs (per brighton criteria for jhs) include ability to bend over & put palms on floor & touch thumb to inside of arm. Jhs of no great concern except joints have greater than normal potential for injury from severe physical trauma & evolution of fibromyalgia. Study yoga & avoid extreme sports.