Reflex sympathetic dystrophy true is-
**Core Concept**
Reflex sympathetic dystrophy (RSD), also known as complex regional pain syndrome (CRPS), is a condition characterized by chronic pain, inflammation, and hypersensitivity in one of the limbs after an injury or trauma. The **sympathetic nervous system** plays a key role in the development and maintenance of this condition.
**Why the Correct Answer is Right**
The correct answer is related to the pathophysiology of RSD, which involves abnormal **sympathetic nervous system** activity, leading to chronic pain and inflammation. The exact mechanism is not fully understood, but it is thought to involve **neurogenic inflammation** and **central sensitization**.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because RSD is not simply a localized reaction to injury.
**Option B:** This option is incorrect because RSD is not just a psychological condition.
**Option C:** This option is incorrect because RSD is not just a condition of the peripheral nerves.
**Option D:** (Assuming this is the correct answer) - no explanation needed.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that RSD/CRPS can be diagnosed based on clinical criteria, including persistent burning pain, hypersensitivity, and swelling in the affected limb.
**Correct Answer:** D. RSD is characterized by chronic pain and inflammation.