Ulnar Nerve Palsy

Ulnar nerve palsy

Low Ulnar Nerve Palsy

– the major functional deficits are weakness of pinch (adductor pollicis), weakness of grip (intrinsic paralysis) and sometimes clawing of the ring and little fingers.

– weakness of pinch secondary to loss of thumb ADDUCTION (adductor pollicis paralysis)

– this should be restored, as it represents a major loss of function

Transfers: (to restore thumb adduction)
FDS of 4 swung over to thumb (Brand)
Brachioradialis or ECRL to a free tendon graft (plantaris or palmaris longus) through the 3-4 interspace, then through the palm to the thumb (Boyes)
FDS of 4 split into two limbs then swung over to thumb (Royle-Thompson)
FDS of 4 split into 3 limbs, one to the thumb, the other two transferred dorsally to 4
and 5 to restore intrinsic function (Omer)

– the loss of intrinsic power make grip weak:

Transfers: (to restore intrinsic power)
FDS transfer from volar to dorsal (Bunnell)
EDC 3 and 4 split then transferred under deep transverse metacarpal ligament then dorsally
again (Fowler)
ECRL or ECRB to a free plantaris graft (divided into 4) then transferred under deep
transverse metacarpal ligament, then dorsally again (Brand)

– to prevent the clawing, the MCP’s should be stabilized so that they don’t fall into hyperextension: (this allows the fingers to be flexed by the extrinsics and extended by the extrinsics.

Procedures: (to stabilize the MCPs)
volar capsulodesis (Zancolli)
tenodesis (Riordan)

High Ulnar Nerve Palsy

– all the same applies, but you cannot use FDS of 4 because its FDP is also paralyzed. Flexion of the ring and little finger can be restored by suturing their FDPs to that of the long FDP.