Klumpke’s palsy is due to injury to the following nerves:
**Core Concept**
Klumpke's palsy is a form of brachial plexus injury, specifically affecting the lower trunk of the plexus. This condition is characterized by weakness or paralysis of the small muscles of the hand and forearm. The **lower trunk of the brachial plexus** is primarily involved.
**Why the Correct Answer is Right**
The correct answer involves the injury to the **lower trunk of the brachial plexus**, which comprises the C8 and T1 nerve roots. These roots give rise to the **ulnar nerve** and the **median nerve**, which are responsible for the motor and sensory functions of the hand and forearm. Damage to these nerves results in the characteristic symptoms of Klumpke's palsy.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it does not specify the correct nerve roots involved in Klumpke's palsy.
**Option B:** Incorrect as it refers to a different part of the brachial plexus.
**Option C:** Incorrect because it involves higher nerve roots not associated with Klumpke's palsy.
**Option D:** Incorrect as it is not related to the brachial plexus injury.
**Clinical Pearl / High-Yield Fact**
Klumpke's palsy is often associated with a **claw hand deformity** due to the unopposed action of the flexor digitorum profundus and the loss of function of the lumbricals and interosseous muscles. This condition can occur due to traumatic birth injury or other forms of trauma affecting the brachial plexus.
**Correct Answer:** D. Lower trunk of the brachial plexus (C8 and T1 nerve roots)