Kennedy phenomenon is seen in: NEET 13
**Question:** Kennedy phenomenon is seen in: NEET 13
**Core Concept:** Kennedy phenomenon refers to the temporary relief of symptoms in a patient with a known spinal cord injury. This occurs due to reflex sympathetic dystrophy (RSD), also known as complex regional pain syndrome (CRPS). RSD is a chronic pain disorder that affects the peripheral nervous system and is characterized by pain, swelling, and abnormal skin color.
**Why the Correct Answer is Right:** Kennedy phenomenon occurs in patients with spinal cord injury, where the affected limb is immobilized and the patient is distracted (usually by a conversation). The immobilization and distraction lead to a decrease in sympathetic activity, which in turn reduces the symptoms of RSD. This temporary relief of symptoms is an important clinical clue for the diagnosis of RSD.
**Why Each Wrong Option is Incorrect:**
A. This option is incorrect because Kennedy phenomenon is not seen in patients with peripheral nerve injury or spinal cord injury at the level of the peripheral nerves (e.g., upper extremity).
B. This option is incorrect as Kennedy phenomenon is not seen due to hypothermia or hyperthermia. The phenomenon is specific to sympathetic dystrophy and sympathetic blockade.
C. This option is incorrect because Kennedy phenomenon is not seen due to reflex sympathetic activity, but rather due to a reduction in sympathetic activity.
D. This option is incorrect because Kennedy phenomenon is not seen due to the administration of local anesthetics, as the phenomenon is related to sympathetic dystrophy rather than local anesthetic effects.
**Clinical Pearl:** Kennedy phenomenon is a valuable clinical clue for the diagnosis of RSD in patients with spinal cord injury. The phenomenon should prompt further evaluation for RSD, as it can help differentiate RSD from other conditions with similar symptoms, such as reflex sympathetic dystrophy and reflex sympathetic dystrophy. It is essential for clinicians to recognize this phenomenon to initiate appropriate treatment and provide better care for patients suffering from RSD.