Below is a great video that breaks down the fundamental components of the Ulnar Nerve. I will highlight a few key points, but I recommend watching the video as well.
Ulnar Nerve Quick Facts:
1) The ulnar nerve originates from C8-T1 nerve roots.
2) It does not give off any branches in the axilla or upper arm
3) The nerve passes between the 2 heads of the flexor carpi ulnaris
4) Tinel's Sign can be used for assessing cubital tunnel syndrome
5) The nerve enters the palm through Guyon's Canal
6) The deep branch of the ulnar nerve innervates the three hypothenar muscles, two medial lumbricals, seven interossei, the adductor pollicis, and deep head of the FPB
7) The ulnar nerve provides sensory innervation to the little finger and half the ring finger
8) A claw hand deformity is due to unopposed pull of the flexor digitorum profundus.
Enjoy the video!