olecranon Ulnar Radial notch -trochlear notch coronoid process ·Upper end: UInar tubersity olecranon coronoid process trochlear notch(large curved articular surface) radial notch ulnar ulnar tubersity ·Lower end styloid process of ulnar head of ulnaUlnar • Upper end: olecranon coronoid process trochlear notch (large curved articular surface) radial notch ulnar tubersity • Lower end styloid process of ulnar head of ulna trochlear notch olecranon Ulnar tubersity coronoid process ulnar Radial notch