Ulna Nerve



Low Lesion (Below Elbow)


Injury usually at wrist

- laceration at wrist

- fenetrating forearm wound


Ulna nerve laceration wrist


High lesion / Above elbow


Injury usually at elbow

- elbow fracture / dislocation

- compression (GA) 

- tardy ulna palsy


Low Lesion


1.  Claw hand deformity



- hyperextension all MCPJ 

- flexion of IPJ of Ring & Little fingers


A.  Absent lumbricals - loss of MCPJ flexion / IPJ extension to RF & LF


2.  Unopposed MCPJ extension - EDC 


3.  IPJ flexed by long flexors - less marked in high lesion because ulnar FDP paralysed


2.  Loss of interossei 


Weak finger abduction / adduction

Positive Froment's sign

Hypothenar & Interossei wasting




3.  Numbness of ulnar  1 & 1/2 fingers


May have numbness of ulnar dorsum of hand

- depends on level of lesion

- if forearm, take out dorsal branch ulna nerve


High Lesion

Above +


A.  RF / LF FDP loss

- ulna paradox with less clawing 


B.  FCU weak

- weak wrist flexion




1.  Restore pinch / thumb stability

- thumb adduction (interposition to BR/ECRB)

- index abduction (EPB to 1st Dorsal Interossei)


2.  Correct MCPJ clawing


Management Low Ulna Palsy


1.  Thumb adduction


No donor long enough

- FDP LF tendon to BR / ECRB



- need interposition graft  i.e. FDP to LF)

- graft fixed to base P1 / normal insertion

- tendon passed along a line form base of MC III /  line of pull of Adductor

- bring out through dorsum between III and IV MC's

- attach to donor tendon BR or ECRB


2.  Index Finger abduction


EPB to 1st dorsal interossei


3.  Clawing of MCPJ




Prevent hyperextension of MCPJ's

- Want to create FFD





- Zancolli Capsulodesis / volar plate advancement



- reconstruction lumbricals

- split MF FDS / ECLR into 4


Zancolli Capsulodesis 


Transverse palmar incision

- each A1 pulley opened

- flexor tendons retracted


Volar plate raised as distally based flap & advanced proximally


Finger flexed to 20°

- volar plate sutured to new position

- mild FFD MCPJ created


Management High Ulna Palsy


1. FDP to ring and little


Buddy to middle FDP



- FDP flexes IPJ's before MCPJ's

- this unopposed flexion of IPJ can push object out of palm


2. FCU


Split FCR to FCU