Anatomy Tutorial 7, Upper Limb

Anatomy Tutorial 7 (Upper Limb: part 1)

Anatomy Tutorial 7 (Upper Limb: part 2)

Anatomy Tutorial 7 (Upper Limb: part 3)

Anatomy Tutorial (Upper Limb: part 4)

Nerves of the Upper Limb, N467 Notes, Anatomy, Upper Limb, Neurovasculature

Nothing noteworthy here

Nerves of the Upper Limb, N467 Notes, Anatomy, Upper Limb, Neurovasculature

Radial Nerve in Arm and Nerves of Posterior Shoulder, N465 Notes, Anatomy, Upper Limb, Neurovasculature

1. Dorsal scapular Nerve (Root C5)
1. Levator Scapulae
2. Rhomboid Minor Muscle
3. Rhomboid Major Muscle
2. Suprascapular Nerve (Root C5, C6)
1. Supraspinatus Muscle
2. Infraspinatus muscle
3. ? Articular Innervation of Glenoheumaral Joint
3. Lower Subscapular nerve
1. Subscapularis Muscle
2. Teres Major Muscle 
4. Axillary Nerve (Root C5, C6) - (middle trunk, posterior division, posterior cord)
1. Muscle
1. Deltoid Muscle
2. Teres Minor Muscle
3. Long Head of the Triceps Brachii
2. Sensory
1. Shoulder Joint
2. Superior Lateral Cutaneous Nerve
5. Radial Nerve (Roots C5,C6, C7, C8, T1) - Terminal Branch of the Posterior Cord of the Brachial Plexus
1. Course
1. Through the Triangular Space of the axilla
2. Triceps Brachii
1. After giving off branches to the long and medial heads of the triceps brachii, it enters a groove on the humerus, the radial sulcus, where it innervates the lateral head of the triceps.
3. Pierces the Lateral Intermuscular Septum and enters the anterior compartment of the arm
2. Motor
1. Muscular Branches
1. Triceps Brachii
2. Aconeous
3. Brachioradialis
4. Extensor Carpi Radialis Longus
2. Deep Branch of radial nerve
1. Extensor Carpi Radialis Brevis
2. Supinator
3. Posterior Interosseous Nerve
1. Extensor digitorum
2. Extensor digiti minimi
3. Extensor Carpi Ulnaris
4. Abductor Pollicis Longus
5. Extensor pollicis Brevis
6. Extensor Pollicis longus
7. Extensor Indicis
3. Cutaneous Nerves
1. Inferior Lateral Brachial Cutaneous Nerve
2. Posterior Brachial Cutaneous Nerve
3. Posterior Antebrachial Cutaneous Nerve
4. Superficial Branch Radial Nerve

Radial Nerve in Arm and Nerves of Posterior Shoulder, N465 Notes, Anatomy, Upper Limb, Neurovasculature

Ulnar Nerve, N464 Notes, Anatomy, Upper Limb, Neurovasculature

Innervates	flexor carpi ulnaris flexor digitorum profundis lumbrical muscles opponens digiti minimi flexor digiti minimi abductor digiti minimi interossei adductor pollicis
From	C8, T1 (branches off from Medial cord)

1. Roots of Ulnar Nerve (C8 to T1) of the Median Cord of the Brachial Plexus
2. Forearm - 
1. Flexor Carpi Ulnaris and medial half of Flexor Digitorum Profundus
2. Branches
1. Muscular branches of the Ulnar Nerve
2. Palmar Branches of the Ulnar Nerve
3. Dorsal Branch of the Ulnar Nerve
3. Hand -
1. The Ulnar Nerve and Artery pass superficial to the flexor retinaculum, via the Ulnar Canal
2. Branches of the Ulnar Nerve in the Hand
1. Superficial branch
1. Palmaris Brevis
2. Deep branch
1. Hypothenar Muscles
1. Opponens Digiti Minimi
2. Abductor Digiti Minimi
3. ?Flexor Digiti Minimi Brevis of the hand
2. The 3rd and 4th Lumbrical muscles
3. Dorsal Interossei
4. Palmar Interossei

Hypothenar Muscles:

1. Palmaris Brevis
2. Abductor Digiti Minimi
3. Flexor Digiti Minimi
4. Opponens Digiti Minimi

Ulnar Nerve, N464 Notes, Anatomy, Upper Limb, Neurovasculature

Median Nerve, N463 Notes, Anatomy, Upper Limb, Neurovasculature

Branches from the medial and lateral cords: median nerve (Roots C5, C6, C7, C8, & T1)

1. Is formed by heads from both the medial and lateral cords.
2. Runs down the anteromedial aspect of the arm but does not branch in the brachium. Continues down the arm to enter the forearm with the brachial artery.
3. The median nerve is the only nerve that passes through the carpal tunnel, where it may be compressed to cause carpal tunnel syndrome. 
4. Articular branch to the Elbow
5. Two branches in the forearm:
   • anterior interosseous branch 
   • courses with the anterior interosseous artery and 
   • innervates all the muscles of the anterior compartment of the forearm except the flexor carpi ulnaris and the medial (ulnar) half of flexor digitorum profundus. 
   • It ends with its innervation of pronator quadratus.
   • palmar cutaneous branch of the median nerve arises at the distal part of the forearm. 
   • It supplies sensory innervation to the lateral aspect of the skin of the palm (but not the digits).

Arm - vascular sympathetic branches to the wall of the Brachial artery.

Forearm

• It innervates all of the flexors in the forearm except flexor carpi ulnaris and that part of flexor digitorum profundus that supplies the medial two digits. The latter two muscles are supplied by the ulnar nerve (specifically the Muscular branches of ulnar nerve).
• The main portion of the median nerve supplies the following muscles:

1. Superficial group:

1. Pronator teres
2. Flexor carpi radialis
3. Palmaris longus

1. Intermediate group:

• Flexor digitorum superficialis muscle

1. The anterior interosseus branch of the median nerve supplies the following muscles:

Deep group:

• Flexor digitorum profundus (only the lateral half)
• Flexor pollicis longus
• Pronator quadratus

[edit]Hand

1. motor innervation to the 1st and 2nd lumbrical muscles. 
2. muscles of the thenar eminence by a recurrent thenar branch. The rest of the intrinsic muscles of the hand are supplied by the ulnar nerve.

The median nerve innervates the skin of the palmar side of the thumb, the index and middle finger, half the ring finger, and the nail bed of these fingers. The lateral part of the palm is supplied by the palmar cutaneous branch of the median nerve, which leaves the nerve proximal to the wrist creases. This palmar cutaneous branch travels in a separate fascial groove adjacent to the flexor carpi radialis and then superficial to the flexor retinaculum. It is therefore spared in carpal tunnel syndrome.

The muscles of the hand supplied by the median nerve can be remembered using the mnemonic, "LOAF" for 

1. Lumbricals 1 & 2, 
2. Opponens pollicis, 
3. Abductor pollicis brevis and 
4. Flexor pollicis brevis. Superficial Head only - Deep Head supplied by the Ulnar Nerve

Median Nerve, N463 Notes, Anatomy, Upper Limb, Neurovasculature

Musculocutaneous Nerve, N462 Notes, Anatomy, Upper Limb, Neurovasculature

Musculocutaneous nerve (C5, C6, C7)

1. Pierces the coracobrachialis muscle, descends between the biceps brachii and brachialis muscles, and innervates these three muscles.
2. From the Lateral Cord of the Brachial Plexus
3. Articular Branch 
4. The Lateral Antebrachial Cutaneous Nerve has an Anterior and Posterior Branch

Musculocutaneous Nerve, N462 Notes, Anatomy, Upper Limb, Neurovasculature

Musculocutaneous Nerve, N462 Notes, Anatomy, Upper Limb, Neurovasculature

Musculocutaneous nerve (C5, C6, C7)

1. Pierces the coracobrachialis muscle, descends between the biceps brachii and brachialis muscles, and innervates these three muscles.
2. From the Lateral Cord of the Brachial Plexus
3. Articular Branch 
4. The Lateral Antebrachial Cutaneous Nerve has an Anterior and Posterior Branch

Musculocutaneous Nerve, N462 Notes, Anatomy, Upper Limb, Neurovasculature

Arteries and Nerves of Upper Arm, N461 Notes, Anatomy, Upper Limb, Neurovasculature

Arteries and Nerves of Upper Arm, N461 Notes, Anatomy, Upper Limb, Neurovasculature:

1. Arteries and anastomosis are not labeled
2. Ulnar Nerve, Medial and Radial Nerves
3. Musculocutaneous Nerve
4. Intercostobrachial Nerve
5. Muscles
1. Pronator Teres has a Ulnar Head and a Humeral Head
2. The Brachial Artery Splits into Radial and Ulnar Branch on the Tendon of Biceps Brachii
3. The Supinator Muscle separates the Radial Nerves Superficial and Deep Branches
4. Neurovascular bundle is exposed after cutting flexor digitorum superficialis muscles, and lies on the Flexor Digitorum Profundus

Nerves of the left upper extremity. (Ulnar labeled at center left.)
Latin	nervus ulnaris
Gray's	subject #210 943
Innervates	flexor carpi ulnaris flexor digitorum profundis lumbrical muscles opponens digiti minimi flexor digiti minimi abductor digiti minimi interossei adductor pollicis
From	C8, T1 (branches off from Medial cord)
MeSH	Ulnar+nerve

Cutaneous Innervation of the Wrist and Hand, N460 Notes, Anatomy, Upper Limb, Neurovasculature

Cutaneous Innervation of the Wrist and Hand, N460 Notes, Anatomy, Upper Limb, Neurovasculature:

1. There are 4 Nerves to the hand not 3
1. Musculocutaneous
1. Medial Antebrachial Cutaneous Nerve
2. Lateral Antebrachial Cutaneous Nerve
2. Ulnar Nerve
1. Palmar Branch
2. Palmar Digital Branch
3. Dorsal Branch and 
3. Median Nerve
1. Palmar Branch
2. Palmar Digital Branch
4. Radial
1. Superficial Branch
2. Dorsal Digital Branches (Prox 2/3)
3. Posterior Antebrachial Cutaneous Nerve

Fingers, N459 Notes, Anatomy, Upper Limb, Wrist and Hand

Sagittal Section Finger:

1. Synovial and fibrous sheath for the flexor tendons
2. Articulate cartilage and articular cavity
3. Extensor mechanism consists of the Lateral Band and the Central Tendon
4. Synovial membrane over the joint (not the synovial Sheath for the flexor tendons)

Cross Section through distal phalynx

1. I can see 9 fine nerves - how many can you see?
2. Fine tissue and AREOLAR TISSUE in anterior enclosed space

Arteries and Nerves

1. Dorsal digital artery and Nerve - Proximal 2/3
2. Palmar digital artery and nerve with nutrient branch to epiphysis and metaphysis
3. Dorsal branches of palmar digital arteries and nerves to dorsum of middle and terminal palanges Distal 1/3

Location of Areolar Tissue, 

also referred to as "loose connective tissue".

It may be found in tissue sections from almost every part of the body. It surrounds blood vessels and nerves and penetrates with them even into the small spaces of muscles, tendons, and other tissues. It may likewise be present in the mediastinal extremities. Nearly every epithelium rests on a layer of areolar tissue, whose blood vessels provide the epithelium with nutrition, waste removal, and a ready supply of infection-fighting leukocytes in times of need. Because the abundance of open, fluid-filled space, leukocytes can move about freely in areolar tissue and can easily find and destroy pathogens.

The areolar tissue is found beneath the dermis layer and is also underneath the epithelial tissue of all the body systems that have external openings.

It is also a component of the lamina propria of the digestive and respiratory tracts, the mucous membranes of reproductiveand urinary systems, the stroma of glands, and the hypodermis of the skin.

Extensor Tendon at Wrist, N458, Anatomy, Upper Limb, Wrist and Hand

6 Compartment

1. Compartment 1:
1. Extensor Pollicis Brevis
2. Abductor Pollicis Longus
2. Compartment 2
1. Extensor Carpi Radialis Longus
2. Extensor Carpi Radialis Brevis
3. Compartment 3
1. Extensor Pollicis Longus
4. Compartment 4
1. Extensor Indicis
2. Extensor Digitorum 
5. Compartment 5
1. Extensor Digiti minimi
6. Compartment 6
1. Extensor Carpi Ulnaris

Dorsal Interosseous Muscles

Intertendinous connections

Transverse Fibers of Extensor Expansions (Hoods)

Wrist and Hand: Deep Dorsal Dissection, N457, Anatomy, Upper Limb, Wrist and Hand

Wrist and Hand: Deep Dorsal Dissection, N457, Anatomy, Upper Limb, Wrist and Hand

1. Nerves
1. Superficial branch of radial nerve
1. Dorsal Digital Branches of Superficial Branch of Radial nerve to 1st, 2nd, 3rd and Radial half of the 4th fingers
2. Dorsal Branch of Ulnar Nerve
1. Dorsal Digital Branches of dorsal Branch of Ulnar Nerve
3. Antebrachial Cutaneous Nerve
1. Lateral Antebrachial Cutaneous Nerve
2. Medial Antebrachial Cutaneous Nerve
3. Posterior Antebrachial Cutaneous Nerve 
4. Dorsal branches of Palmar digital branches of Ulnar Nerve and Palmar Digital arteries to dorsum of middle and distal phalanges of 5th and Ulnar half of 4th fingers
5. Dorsal branches of Palmar digital branches of Median Nerve and Palmar Digital arteries to dorsum of middle and distal phalanges of 2nd, 3rd and Radial half of 4th fingers
2. Extensor Retinaculum
3. Thumb
1. Abductor Pollicis Longus
2. Extensor Pollicis Longus and 
3. Extensor Pollicis Brevis
4. Extensor Carpi Ulnaris Tendon
5. Extensor Carpi Radialis
1. Extensor Carpi Radialis Longus Tendon
2. Extensor Carpi Radialis Brevis Tendon

Wrist and Hand: Superficial Dorsal Dissection, N456, Anatomy, Upper Limb, Wrist and Hand

Wrist and Hand: Superficial Dorsal Dissection, N456, Anatomy, Upper Limb, Wrist and Hand:
Posterior (Dorsal) View
Nerves:

1. Superficial branch of radial nerve
2. Posterior Antebrachial Cutaneous Nerve
3. Dorsal branch of the Ulna Nerve
4. Dorsal digital nerves and veing

Communicating branches between the radial and the Ulna Nerves

Vessels

1. Cephalic Vein
2. Basilic Vein

Wrist and Hand: Superficial Radial Dissection, N455, Anatomy, Upper Limb, Wrist and Hand

Wrist and Hand: Superficial Radial Dissection, N455, Anatomy, Upper Limb, Wrist and Hand

Lateral (Radial) View

Nerves:

1. Superficial branch of the Radial Nerve with its medial and lateral branches 
1. Lateral branches to the Lateral Thumb
2. Medial branch to the medical aspect of the thumb - Dorsal Digital branches of the radial nerve

Muscles and tendons

1. Abductor Pollicis longus tendon
2. Insertion of extensor Pollicis Brevius Tendon
3. Insertion of extensor pollicis Longus tendon
1. 1st Dorsal Interosseous Muscle
2. Extensor Carpi Radialis longus tendon
3. Extensor Carpi radialis Brevis tendon

Arteries

1. Radial Artery in the Anatomical Snuffbox with its dorsal carpal branch

Anatomical Snuffbox:

• Radial Nerve (dorsal digital branch)
• Cephalic Vein branches
• Radial Artery and branches
• Scaphoid  bone

Anatomical snuff box
anatomical snuff box
The mucous sheaths of the tendons on the back of the wrist. (Anatomical snuff box not labeled, but visible at right.)
Artery	radial artery
Vein	cephalic vein
Nerve	radial nerve

Pathology

The radius and scaphoid articulate deep to the snuffbox to form the basis of the wrist joint. In the event of a fall onto an outstretched hand, this is the area through which the brunt of the force will focus. This results in these two bones being the most often fractured of the wrist. In a case where there is localized tenderness within the snuffbox, knowledge of wrist anatomy leads to the speedy conclusion that the fracture is likely to be of the scaphoid. This is understandable as the scaphoid is a small, oddly shaped bone whose purpose is to facilitate mobility rather than confer stability to the wrist joint. In the event of inordinate application of force over the wrist, this small scaphoid is clearly likely to be the weak link. Interestingly, scaphoid fracture is one of the most frequent causes of medico-legal issues.

Anatomical peculiarity

An interesting anatomical anomaly in the vascular supply to the scaphoid is the area to which the blood supply is first delivered. Blood enters the scaphoid distally. Consequently, in the event of a fracture the proximal segment of the scaphoid will be devoid of a vascular supply, and will—if action is not taken—avascularly necrose within a sufferer's snuffbox. Due to the small size of the scaphoid and its shape, it is difficult to determine, early on, whether or not the scaphoid is indeed fractured with an x-ray. Further complications include; carpal instability (ligament disruption) and fracture-dislocations.

Anatomy: Upper Limb: Shoulder and Axilla

Muscles of the Rotator Cuff 413  (SITS Muscles plus Ligaments)

1. Ligaments
1. Coracoclavicular Ligament: Conoid and the Trapezoid ligaments
2. Coracoacromial Ligament
2. Muscles tendons
1. Subscapularis tendon
2. Supraspinatus tendon
3. Infraspinatus tendon
4. Teres Minor Tendon
3. Auxillary Nerve emerges inferior to the Teres Minor Muscle

Anatomy: Upper Limb

Humerus and Scapula: Posterior View 408

Note the insertion of Triceps Mm on the olecronon of the Ulna

Shoulder: Anteroposterior Radiograph

Shoulder Glenohumeral Joint 411

Coracoclavicular ligament: Conoid ligament and the trapeziod ligament

Coracoacromial Ligament

Coracohumeral ligament

Capsular ligament

Subscapularis tendon contributes anteriorly

Suprascapularis tendon contributes superiorly

Infraspinatus tendon fused to the capsule

Teres minor tendon fused to capsule

The Subdeltoid bursa fuses with the subacromial bursa

The Glenoid Cavity of the Scapula

Muscles of the shoulder 411

Posterior view 411:

• Spinous process of C7 vertebra is a landmark
• Levator Scapulae
• Rhomboid Muscles: minor superior then the major inferior
• What does the supraspinous muscle do?
• The teres minor muscle snuggles between the Infraspinous and the Teres Major muscle
• 
  
• Again I only see the long head and lateral head of triceps muscle

Anterior View Muscles of the shoulder 411

Trapezius muscle beautifully covers the acromion and the lateral clavicle 

Look at the Omohyoid Muscle deep to Trapezius muscle and the Sternocleidomustoid muscle

The Pectoralis Major has 3 parts: the clavicular part, the Sternal part and the abdominal part

Biceps Brachii has a Long lateral head and a short medial head

Axilla Posterior Wall and Cord 412

Brachial Trunks: Superior, Middle and Inferior emerge deep to the both Pectoralis muscles, and inferior to the clavicle and subclavious muscle

It is superficial to Mm Supraspinatus, and Mm Subscapularis 

The Posterior Cord gives off the Upper Subscapular Nerve, the Thoracodorsal Nerve and the Lower Subscapular Nerve - it then becomes the Radial Nerve. 

The Axillary nerve gives a branch to the Teres Minor Muscle and  Superior Lateral Brachial Nerve, Posterior and anterior branch to Teres Minor Muscle

Well done C Machado MD 

 

Front of the left forearm. Superficial muscles.

 

The triangle of ausculation of the lungs is a relative thinning of the musculature of the back situated along the medial border of the scapula.

Function

Due to the relative thinning of the musculature of the back in the triangle, the posterior thoracic wall is closer to the skin surface, making respiratory sounds able to be heard more clearly with a stethoscope.

To better expose the floor of the triangle, which is made up of the posterior thoracic wall in the 6th and 7th intercostal space, the patient is asked to fold their arms across their chest, medially rotating the scapulae, while bending forward at the trunk.

Shoulder Anterior

The shoulder comprises the part of the body where the humerus attaches to the scapula and refers to the group of structures in the region of the joint. The articulations between the bones of the shoulder make up the shoulder joint. Thesethree bones are: the clavicle (collarbone), the scapula (shoulder blade), and the humerus. The glenohumeral joint is the main joint of the shoulder. It is a ball and socket joint that allows the arm to rotate in a circular fashion or to hinge out and up, away from the body. It is formed by the articulation between the head of the humerus and the lateral scapula The main superficial muscles around the shoulder are the deltiod group, rotator cuff and pectoralis major muscles. The rotator cuff is an anatomical term given to the group of muscles and their tendons that act to stabilize the shoulder, the muscles are Supraspinatus, Infraspinatus, Teres minor and the Subscapularis. The pectoralis major muscle is a thick, fan-shaped muscle, situated at the upper anterior of the chest wall. It makes up the bulk of the chest muscles in the male and lies under the breast in the female. The deltoid muscle group has three sets of fibres anterior, middle and posterior they act to both abduct the arm and stabilise the dhoulder joint.

Clavicle

The clavicle is a long bone that makes up part of the shoulder girdle. It acts as a shunt to keep the scapula in position so the arm can hang freely. Medially it articulates with the manubrium of the sternum at the sternoclavicular joint. At its lateral end it articulates with the acromion of the scapula at the acromioclavicular joint. The entire region is prone to injury and good knowledge of this area will help the radiographer decide which views will demonstrate the injury the best ie Shoulder views, Clavicle views, AC joint or SC joints.

Shoulder Posterior

The scapula forms the posterior part of the shoulder girdle, it is a flat bone, roughly triangular in shape,placed on a posterolateral aspect of the thoracic cage. The medial border of the scapula is a commonly used landmark f