Anomalous Innervations

1.  Richie-comeau

 

Site

- ulna to median in palm

- provides motor to the thenar muscles

- ulna dominate hand

- may be due to RC anastomosis

 

Clinical significance

- carpal tunnel syndrome with no thenar atrophy

 

2.  Martin-Gruber 

 

Site

- median to ulna in forearm

- provides motor function to hypothenar eminence

 

Clinical significance

- cubital tunnel syndrome with no hypothenar atropy

- may be due to MG anastomosis