"extension of the MCP and flexion of the PIP (innervation to the third and fourth lumbricals) resulting in the characteristic ulnar claw"
"Guyon's canal"
"Some conditions that make patients more prone to developing Guyon's canal syndrome are ganglion cysts, hook of hamate fracture and repetitive trauma (e.g. common in cyclists due to handlebar compression)."
"weakness in flexion, abduction and opposition of the little finger (innervation to the hypothenar muscles)"