The brachial plexus is a network of nerves located in the neck and upper back. It is responsible for providing motor and sensory functions to the shoulder, arm, and hand. This complex system of nerves originates from the spinal cord and branches out to control various muscles and sensations in the upper limb. Injuries to the brachial plexus can occur due to trauma, such as accidents or childbirth complications. These injuries can lead to weakness, numbness, or paralysis in the affected arm. Treatment options may include physical therapy, medication, or, in severe cases, surgery to repair damaged nerves.