DAA Case Studies

In regard to Case C, which of the following nerve roots are involved in an upper brachial plexus injury? (MARK ALL CORRECT ANSWERS) A.C6 B.C5 C.T1 D.C8

C5 C6

CASE C: While climbing a mango tree to pick fruit, a boy lost his balance and started to fall. He managed to grab a branch which slowed his descent, but he felt a strong pull in his armpit and had to let go. He landed on the shoulder of his friend who was standing below, forcefully spreading his friend's shoulder and neck. At the local health center, the boy who climbed the tree was diagnosed with a lower brachial plexus lesion and his friend with an upper brachial plexus lesion. 3. What nervous structures were injured to result in the upper brachial plexus lesion?

C5, C6 Medial and Lateral Branches Axillary N Musculocutaneous N An upper brachial plexus lesion involves the nerves originating from the upper trunk of the brachial plexus, typically due to trauma to the upper part of the brachial plexus. It's worth noting that in the scenario described, the boy who climbed the tree experienced a lower brachial plexus lesion when he felt the strong pull in his armpit. His friend, who was standing below and had his shoulder and neck forcefully spread upon impact, experienced an upper brachial plexus lesion.

In regard to Case C, which of the following nerve roots are involved in a lower brachial plexus injury? (MARK ALL CORRECT ANSWERS) A.C6 B.C8 C.C5 D.T1

C8 T1

CASE C: While climbing a mango tree to pick fruit, a boy lost his balance and started to fall. He managed to grab a branch which slowed his descent, but he felt a strong pull in his armpit and had to let go. He landed on the shoulder of his friend who was standing below, forcefully spreading his friend's shoulder and neck. At the local health center, the boy who climbed the tree was diagnosed with a lower brachial plexus lesion and his friend with an upper brachial plexus lesion. 1. What nervous structures were injured to result in the lower brachial plexus lesion?

C8, T1 A lower brachial plexus lesion typically involves the nerves originating from the lower trunk and/or cords of the brachial plexus. The specific nerves that may be injured in a lower brachial plexus lesion are the ulnar nerve (C8-T1 nerve roots) and potentially the medial brachial cutaneous nerve and medial antebrachial cutaneous nerve, which are also derived from the lower trunk. It's worth noting that in the scenario described, the boy who climbed the tree experienced a lower brachial plexus lesion when he felt the strong pull in his armpit. His friend, who was standing below and had his shoulder and neck forcefully spread upon impact, experienced an upper brachial plexus lesion.

In regard to question number 1 under Case A, which of the following nerves were injured? (MARK ALL CORRECT ANSWERS) A.CN XI on the right B.trochlear nerve C.the right spinal accessory nerve D.the left vagus nerve

CN XI on the right the right spinal accessory nerve

In regards to Case D, which spinal nerve was being compressed? A.L3 spinal nerve B.L5 spinal nerve C.S1 spinal nerve D.L4 spinal nerve

L5 spinal nerve

In regard to Case B, the nerve that innervates the muscle that is most likely causing "winging" of the patient's scapula is the _____ thoracic nerve.

Long Thoracic Nerve

CASE D: An individual was lifting a heavy object when they suddenly felt severe back pain that radiated down the posterior aspect of their right thigh and leg. MRI revealed a protruding intervertebral disc between L4 and L5 vertebrae. 1. What ligaments connect the vertebrae on the posterior aspects of the vertebral bodies?

Posterior Longitudinal Ligament (PLL) and Tectorial Membrane

CASE A: A patient schedules an appointment in your clinic and would like to receive treatment for some complications from a previous neck surgery. The patient presents with the following: their head slightly laterally flexed to the left with their face turned to the right and upwards, numbness over part of the right auricle and skin over the parotid gland, and some difficulty in tongue movement. 1. What nerve and muscle were injured to cause their face to turn upward to the right?

Right Sternocleidomastoid Muscle (SCM) Right side not working CN XI (Spinal) Accessory Nerve Damaged The patient's head being slightly laterally flexed to the left with their face turned to the right and upwards suggests an injury to the accessory nerve (cranial nerve XI) and the sternocleidomastoid muscle on the left side. The accessory nerve innervates the sternocleidomastoid and trapezius muscles, and when it is injured, it can lead to weakness or paralysis of these muscles, causing the head to tilt and rotate.

CASE C: While climbing a mango tree to pick fruit, a boy lost his balance and started to fall. He managed to grab a branch which slowed his descent, but he felt a strong pull in his armpit and had to let go. He landed on the shoulder of his friend who was standing below, forcefully spreading his friend's shoulder and neck. At the local health center, the boy who climbed the tree was diagnosed with a lower brachial plexus lesion and his friend with an upper brachial plexus lesion. 4. What motor functions would be affected and where would sensory loss be noted due to this lesion?

Sensory is Lateral shoulder and forearm • Motor : abduction and medial and lateral rotation Motor functions affected by an upper brachial plexus lesion: Weakness or paralysis of the muscles innervated by the musculocutaneous nerve (C5-C7 nerve roots) and the axillary nerve (C5-C6 nerve roots). This includes the anterior arm muscles (e.g., biceps brachii, brachialis, coracobrachialis) and the deltoid muscle. Sensory loss in the distribution of the axillary nerve, which includes the lateral aspect of the shoulder region. It's worth noting that in the scenario described, the boy who climbed the tree experienced a lower brachial plexus lesion when he felt the strong pull in his armpit. His friend, who was standing below and had his shoulder and neck forcefully spread upon impact, experienced an upper brachial plexus lesion.

CASE C: While climbing a mango tree to pick fruit, a boy lost his balance and started to fall. He managed to grab a branch which slowed his descent, but he felt a strong pull in his armpit and had to let go. He landed on the shoulder of his friend who was standing below, forcefully spreading his friend's shoulder and neck. At the local health center, the boy who climbed the tree was diagnosed with a lower brachial plexus lesion and his friend with an upper brachial plexus lesion. 2. What motor functions would be affected and where would sensory loss be noted due to this lesion?

Sensory=Medial Aspect of Arm & forearm- -Ulnar N Anterior Compartment - Ulnar Deviation, ADDuction/ABduction, flexion of wrist and digits (fingers) Motor functions affected by a lower brachial plexus lesion: Weakness or paralysis of the muscles innervated by the ulnar nerve, including the intrinsic hand muscles (e.g., interossei, hypothenar muscles) and some forearm muscles (e.g., flexor carpi ulnaris). Sensory loss in the distribution of the ulnar nerve, which includes the medial aspect of the hand (pinky finger and half of the ring finger) and the corresponding part of the palm. It's worth noting that in the scenario described, the boy who climbed the tree experienced a lower brachial plexus lesion when he felt the strong pull in his armpit. His friend, who was standing below and had his shoulder and neck forcefully spread upon impact, experienced an upper brachial plexus lesion.

CASE D: An individual was lifting a heavy object when they suddenly felt severe back pain that radiated down the posterior aspect of their right thigh and leg. MRI revealed a protruding intervertebral disc between L4 and L5 vertebrae. 2. What are the parts of an intervertebral disc?

The intervertebral disc has two main parts: 1. Annulus fibrosus: This is the tough, fibrous outer layer of the disc that surrounds the inner core. 2. Nucleus pulposus: This is the soft, gel-like inner core of the disc.

CASE B: A patient presents to your office with shoulder pain in the front of their shoulder. They complain of it hurting when they bring their arm overhead (such as trying to perform full abduction of the arm), or when lifting anything more than 5lbs. Notable exam findings were that while standing, the patient's left scapula was "winging", and the winging gets worse when their scapula is abducted (protracted). 2. What nerve is most likely involved? In reference to question number 1.

The long thoracic nerve (also known as the long thoracic nerve of Bell) is most likely involved in this case. The long thoracic nerve innervates the serratus anterior muscle, and damage or dysfunction to this nerve can lead to weakness or paralysis of the serratus anterior, causing scapular winging. Scapular winging is characterized by the abnormal protrusion or "winging" of the scapula away from the ribcage during certain movements, like arm abduction or protraction. This weakness in the serratus anterior can lead to difficulty in stabilizing the scapula during overhead movements, resulting in pain and limited shoulder function.

CASE B: A patient presents to your office with shoulder pain in the front of their shoulder. They complain of it hurting when they bring their arm overhead (such as trying to perform full abduction of the arm), or when lifting anything more than 5lbs. Notable exam findings were that while standing, the patient's left scapula was "winging", and the winging gets worse when their scapula is abducted (protracted). 1. Which muscle is most likely involved when given these findings? Specifically, the winging of the scapula.

The muscle that is most likely involved in the winging of the scapula based on the given findings is the serratus anterior muscle.

In regard to Case A, which of the following nerves were injured to result in difficulty in tongue movement? (MARK ALL CORRECT ANSWERS) A.hypoglossal nerve B.abducens nerve C.glossopharyngeal nerve D.CN XII

hypoglossal nerve CN XII

In regard to Case C, which of the following choices represents an area you would expect to find sensory loss with a lower brachial plexus injury? (MARK ALL CORRECT ANSWERS) A.lateral portion of the hand B.lateral antebrachium C.medial portion of the hand D.medial antebrachium

medial portion of the hand medial antebrachium

In regards to Case D, what part of the intervertebral disc would be protruding and in which direction would it usually herniate? A.anulus fibrosus; posterior and medial B.nucleus pulposus; posterior and lateral C.anulus fibrosus; anterior and medial D.nucleus pulposus; anterior and medial

nucleus pulposus; posterior and lateral

In regard to Case B, which of the following muscles is most likely causing "winging" of the patient's scapula? A.levator scapulae B.pectoralis minor C.serratus anterior D.teres minor

serratus anterior

In regard to question number 2 under Case A, which of the following choices represent a nerve that was injured? A.the right ansa cervicalis nerve B.the left greater auricular nerve C.the right transverse cervical nerve D.the right greater auricular nerve

the right greater auricular nerve

CASE D: An individual was lifting a heavy object when they suddenly felt severe back pain that radiated down the posterior aspect of their right thigh and leg. MRI revealed a protruding intervertebral disc between L4 and L5 vertebrae. 4. Which spinal nerve would be compressed by the herniated disc and why?

• L4 exits in between L4-LS + In this case. L5 is being compressed because the spinal cord stops at cauda equina (LI,L2), so it is after the spinal cord ends, (so it's NOT L4). Disks in lumbar are larger. In the case of a protruding intervertebral disc between L4 and L5 vertebrae, the L5 spinal nerve would be compressed by the herniated disc. The herniation occurs at the L4-L5 level, and as the nucleus pulposus protrudes backward, it can compress the exiting L5 nerve root as it passes through the neural foramen. This compression can result in radiating pain down the posterior aspect of the right thigh and leg, a condition known as sciatica. The L5 nerve root is responsible for providing motor and sensory innervation to certain muscles in the leg and foot, so compression of this nerve can cause pain, weakness, and sensory changes in the affected areas.

CASE D: An individual was lifting a heavy object when they suddenly felt severe back pain that radiated down the posterior aspect of their right thigh and leg. MRI revealed a protruding intervertebral disc between L4 and L5 vertebrae. 3. Which part of the disc would be protruding, and in which direction would it usually herniate?

• Posterolateral - nucleus will be protruding out The protruding part of the intervertebral disc would be the nucleus pulposus. It usually herniates posteriorly, which means it bulges backward toward the spinal canal and the spinal nerves.