`Ulnar paradox’ is seen in –
**Core Concept**
The "ulnar paradox" refers to a phenomenon where the ulnar nerve is compressed or damaged, leading to a characteristic pattern of symptoms and signs that might seem counterintuitive. This paradoxical presentation is due to the complex innervation of the forearm and hand.
**Why the Correct Answer is Right**
The ulnar paradox occurs when the ulnar nerve is compressed or damaged at the elbow, leading to a combination of symptoms including paralysis of the intrinsic muscles of the hand, clawing of the 4th and 5th fingers, and loss of sensation over the 5th finger and the ulnar aspect of the 4th finger. This is because the ulnar nerve supplies the intrinsic muscles of the hand, but not the flexor carpi ulnaris or the ulnar half of the flexor digitorum profundus, which are responsible for wrist flexion and finger flexion, respectively.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is likely incorrect because the ulnar paradox is not typically associated with radial nerve compression or damage.
**Option B:** This option is incorrect because the ulnar paradox is not typically associated with median nerve compression or damage, which would cause different symptoms, such as thenar muscle weakness and sensory loss over the thumb, index, and middle fingers.
**Option C:** This option is incorrect because while the ulnar paradox can be associated with Guyon's canal syndrome, it is not the only condition that can cause this phenomenon.
**Clinical Pearl / High-Yield Fact**
The ulnar paradox highlights the importance of careful clinical examination and localization of nerve compression or damage in patients with hand and wrist symptoms.
**Correct Answer:** C.