The Upper Limb Ernest F. Talarico, Jr., Ph.D. Associate Director of Medical Education Associate Professor of Anatomy & Cell Biology Associate Faculty, Radiologic Sciences Indiana University School of Medicine – Northwest Campus

Objectives To gain a comprehensive understanding of the osteology of the upper limb To understand and be able to discuss the anatomy/anatomical relationships of the upper limb (i.e., veins, arteries, compartments, muscles) To understand the brachial plexus Apply the above to a case study of the brachial plexus and medical imaging.

Upper Limb Osteology Right Clavicle Brachium Antebrachium Carpus Manus Phalanges Right Clavicle

Fascia ☺ Compartment ☺ Lymphatics

Veins and Lymphatics of the Upper Limb

Muscles of the Brachiium Posterior Radial n. What is the view? What is the innervation? (anterior) (Musculocutaneous n.)

Muscles of the Antebrachium

Muscles of the Antebrachium

Muscles of the Antebrachium

Compartment & Muscles of the Manus

An Area of Concern!

Vessels

1 2 3 Lateral boarder of R1 and medial border of pectoralis minor m. Superior (supreme) Thoracic a. Posterior to pectoralis minor m. Thoracoacromial a. (Acromial, Clavicular, Pectoral, Deltoid) Lateral Thoracic a. (**** BREAST ****) Lateral border of pectoralis minor m. and the inferior border of teres major m. Subscapular a. (largest) Anterior & Posterior Circumflex Humeral aa. (P > A)

Anatomical Relationships - Vessels/Nerves

The Brachial Plexus Innervates all muscles of superior extremity Sensory & motor nerves Anterior division fibers supply flexors Posterior division fibers supply extensors Roots Trunks Divisions Cords Branches Robert Taylor Drinks Cold Beer

IUSM-NW 2007 - 17

Spinal Nerves (31 pairs) all are mixed nerves (sensory and motor) 4 fiber components Sensory GSA: general somatic afferent GVA: general visceral afferent Motor GSE: skeletal GVE: visceral IUSM-NW 2007 - 18

Typical Thoracic Spinal Nerve 31 pairs of spinal nerves: 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal IUSM-NW 2007 - 19

Brachial Plexus: Major Branches Musculocutaneous (C5-7) Median Nerve (C6-T1) Ulnar Nerve (C8-T1) Axillary Nerve (C5-6) Radial Nerve (C7-8)

Brachial Plexus: Major Branches Musculocutaneous (C5-7) Biceps Brachii (C5, C6) Coracobrachialis (C5, C6, C7) Brachialis (C5, C6)

Brachial Plexus: Major Branches Median Nerve (C6-T1) Pronator teres Flexor carpi radialis Palmaris longus Flexor digitorum profundus (lateral) Flexor digitorum superficialis Flexor pollicus longus Pronator quadratus and hand mm.

Brachial Plexus: Major Branches Ulnar Nerve (C8-T1, often C7)  + 13 hand mm. Flexor digitorum profundus (medial) Flexor carpi ulnaris

Brachial Plexus: Major Branches Axillary Nerve (C5-6) Deltoid Teres minor

Brachial Plexus: Major Branches Radial Nerve (C5-T1)  12 + anconeus Brachioradialis Triceps brachii (C6, C7, C8) Extensor carpi radialis longus and brevis Extensor digitorum Extensor digiti minimi Extensor carpi ulnaris Supinator Abductor pollicus longus Extensor pollicus longus and brevis Extensor indicus

Brachial Plexus: Other Nerves Dorsal Scapular (C5) Rhomboideus major and minor Levator scapulae Suprascapular (C5-6) Supraspinatus Infraspinatus Shoulder joint Subclavian (C5-6) Subclavius Lateral Pectoral (C5-C7) Pectoralis major and minor

Upper Subscapular (C5-6) Subcapularis Thoracodorsal (C6-8) Latissimus dorsi Lower Subscapular (C5-6) Teres major Long Thoracic (C5-7) Seratus anterior Medial Pectoral (C8-T1) Pectoralis minor and major Medial Brachial Cutaneous Medial Antebrachial Cutaneous

Brachial Plexus

Nerves of the Upper Limb

CLNICAL CORRELATION

Medical Imaging

Swan Neck Deformity A swan neck deformity describes a finger with a hyperextended PIP joint and a flexed DIP joint.

How does this condition occur? Conditions that loosen the PIP joint and allow it to hyperextend can produce a swan neck deformity of the finger. Rheumatoid arthritis (RA) is the most common disease affecting the PIP joint. The small (intrinsic) muscles of the hand and fingers can tighten up from hand trauma. Various nerve disorders, such as cerebral palsy, Parkinson's disease, or stroke.

Mallet Finger

How do these injuries of the DIP joint occur? A mallet finger results when the extensor tendon is cut or torn from the attachment on the bone. Sometimes, a small fragment of bone may be pulled, or avulsed, from the distal phalanx. The result is the same in both cases: the end of the finger droops down and cannot be straightened.

Boutonniere Injury Boutonnière deformity (buttonhole deformity) is a deformity in which the middle finger joint is bent in a fixed position inward (toward the palm) and the outermost finger joint is bent excessively outward (away from the palm). This disorder most often results from rheumatoid arthritis but can also occur from injury (such as deep cuts, joint dislocation, or fractures) or osteoarthritis

A 34-year-old, African-American male, falls from the roof of a new home under construction and lands on a cement boulder with impact on the right, proximal one-third of the humeral diaphysis. Medical history is significant for HTN, diabetes, and hypercholesterolemia. Examination in the ER is remarkable for BP 168/90; T 99.9; P 90; R 28. Bone is evident topographically near the deltoid tuberosity, and there is bleeding. Inflammatory response is active and there is decreased ROM; flexor and extensor reflexes are intact. CT reveals shattered humeral diaphysis with displacement. Surgical intervention is consistent with internal fixation and bone grafting using osseous tissue from the ilium ground and mixed with sea coral. The anterior and posterior circumflex humeral arteries were noted to be intact, and were clamped during surgery to facilitate repair. Three weeks post-surgery, the patient complains of significant pain near the site of injury. MRI reveals AVN of the proximal humeral diaphysis. Which of the following selections best explains the patient’s condition? A. nonunion of bone fragments B. malpractice on the part of the surgeon C. diabetes D. muscle injury E. neuropathy

A 34-year-old, African-American male, falls from the roof of a new home under construction and lands on a cement boulder with impact on the right, proximal one-third of the humeral diaphysis. Medical history is significant for HTN, diabetes, and hypercholesterolemia. Examination in the ER is remarkable for BP 168/90; T 99.9; P 90; R 28. Bone is evident topographically near the deltoid tuberosity, and there is bleeding. Inflammatory response is active and there is decreased ROM; flexor and extensor reflexes are intact. CT reveals shattered humeral diaphysis with displacement. Surgical intervention is consistent with internal fixation and bone grafting using osseous tissue from the ilium ground and mixed with sea coral. The anterior and posterior circumflex humeral arteries were noted to be intact, and were clamped during surgery to facilitate repair. Three weeks post-surgery, the patient complains of significant pain near the site of injury. MRI reveals AVN of the proximal humeral diaphysis. Which of the following selections best explains the patient’s condition? A. nonunion of bone fragments B. malpractice on the part of the surgeon C. diabetes D. muscle injury E. neuropathy Based on your knowledge of anatomy of the upper limb, what is the most likely cause of the AVN and the patient’s pain? Question

A 34-year-old, African-American male, falls from the roof of a new home under construction and lands on a cement bolder with impact on the right, proximal one-third of the humeral diaphysis. Medial history is significant for HTN, diabetes, and hypercholesterolemia. Examination in the ER is remarkable for BP 168/90; T 99.9; P 90; R 28. Bone is evident topographically near the deltoid tuberosity, and there is bleeding. Inflammatory response is active and there is decreased ROM; flexor and extensor reflexes are intact. CT reveals shattered humeral diaphysis with displacement. Surgical intervention is consistent with internal fixation and bone grafting using osseous tissue from the ilium ground and mixed with sea coral. The anterior and posterior circumflex humeral arteries were noted to be intact, and were clamped during surgery to facilitate repair. Three weeks post-surgery, the patient complains of significant pain near the site of injury. MRI reveals AVN of the proximal humeral diaphysis. Which of the following selections best explains the patient’s condition? A. nonunion of bone fragments B. malpractice on the part of the surgeon C. diabetes D. muscle injury E. neuropathy Based on your knowledge of anatomy of the upper limb, what is the most likely cause of the AVN and the patient’s pain? Question Objective: Is to test the student doctor’s understanding of anatomical and vascular relationships of the upper limb.

A 34-year-old, African-American male, falls from the roof of a new home under construction and lands on a cement boulder with impact on the right, proximal one-third of the humeral diaphysis. Medical history is significant for HTN, diabetes, and hypercholesterolemia. Examination in the ER is remarkable for BP 168/90; T 99.9; P 90; R 28. Bone is evident topographically near the deltoid tuberosity, and there is bleeding. Inflammatory response is active and there is decreased ROM; flexor and extensor reflexes are intact. CT reveals shattered humeral diaphysis with displacement. Surgical intervention is consistent with internal fixation and bone grafting using osseous tissue from the ilium ground and mixed with sea coral. The anterior and posterior circumflex humeral arteries were noted to be intact, and were clamped during surgery to facilitate repair. Three weeks post-surgery, the patient complains of significant pain near the site of injury. MRI reveals AVN of the proximal humeral diaphysis. Which of the following selections explains the patients condition? A. nonunion of bone fragments B. malpractice on the part of the surgeon C. diabetes D. muscle injury E. neuropathy Based on you knowledge of anatomy of the upper limb, what is the most likely cause of the AVN and the patient’s pain? Question Objective: Is to test the student doctor’s understanding of anatomical and vascular relationships of the upper limb. Confirmation Reasoning Elimination