Ulnar paradox is due to:

Ulnar paradox The higher the lesion of the median and ulnar nerve injury , the less prominent is the deformity and vice versa, because in higher lesions the long finger flexors are also paralysed (which were causing interphalangeal flexion/clawing). The loss of finger flexion makes the deformity look less obvious/ less clawing In low ulnar nerve palsy forearm muscles are spared but the clawing is more ( as compared to high ulnar nerve palsy) because in low ulnar nerve palsy finger flexors are spared which adds on to the deformity by flexing IP joints.