Studying anatomy & physiology grouped by regions of the body.
WORK IN PROGRESS…LAST UPDATE 01.20.2020
Bony Landmarks of the Humerus
| Head of humerus | Lateral supracondylar ridge |
| Greater tubercle | Lateral epicondyle |
| Lesser tubercle | Medial epicondyle |
| Anatomical neck | Radial fossa |
| Surgical neck | Capitulum |
| Intertubercular groove or sulcus | Trochlea |
| Deltoid tuberosity | Coronoid fossa |
| Shaft | Olecranon fossa |
Bony Landmarks of the Ulna
| Olecranon process | Styloid process of ulnar |
| Coronoid process | Radial notch |
| Interosseous border | Trochlear notch |
| Head of ulna |
Bony Landmarks of the Radius
| Head of radius (articular disc) | Interosseous border |
| Neck of radius | Radial tuberosity |
| Anterior surface | Posterior border |
| Anterior border | Posterior surface |
| Styloid process | Lateral surface |
| Suprastyloid crest | Ulnar notch |
| Articular surface for carpals | Dorsal tubercle |
Anterior Compartment of Forearm, Superficial
| Pronator Teres | medial epicondyle of humerus, and coronoid process of ulna. | midlateral surface of radius. | pronates forearm at radioulnar joints and weakly flexes forearm at elbow joint. |
| Flexor Carpi Radialis | medial epicondyle of humerus. | second and third metacarpals. | flexes and abducts hand (radial deviation) at wrist joint. Lesser: elbow flexion, forearm pronation. |
| Palmaris Longus | medial epicondyle of humerus. | flexor retinaculum and palmar aponeurosis (fascia in center of palm). | weakly flexes hand at wrist joint. Lesser: wrinkles skin of palm; elbow flexion; pronation; radial deviation of hand; ulnar deviation of hand. |
| Flexor Carpi Ulnaris | medial epicondyle of humerus and superior posterior border of ulna. | pisiform, hamate, and base of fifth metacarpal. | flexes and adducts hand (ulnar deviation) at wrist. Lesser: elbow flexion. |
Innervated by the median nerve (ventral rami of C5-T1).
Anterior Compartment of Forearm, Intermediate & Deep
| Flexor Digitorum Superficialis | medial epicondyle of humerus, coronoid process of ulna and a ridge along lateral margin of anterior surface (anterior oblique line) of radius. | middle phalanx of each finger. | flexes middle phalanx of each finger at proximal interphalangeal joint, proximal phalanx of each finger at metacarpophalangeal joint, and hand at wrist joint. |
| Flexor Digitorum Profundus | anterior medial surface of body of ulna. | base of distal phalanx of each finger. | flexes distal and middle phalanges of each finger at interphalangeal joints, proximal phalanx of each finger at metacarpophalangeal joint, and hand at wrist joint. |
| Flexor Pollicis Longus | anterior surface of radius and interosseous membrane (sheet of fibrous tissue that holds shafts of ulna and radius together). | base of distal phalanx of thumb. | flexes distal phalanx of thumb at interphalangeal joint; wrist flexion. Lesser: radial deviation; forearm flexion; pronation. |
| Pronator Quadratus | distal portion of ulnar shaft. | distal portion of radial shaft. | pronates forearm. |
Innervated by the median nerve (C5-T1). Medial part of profUndUs –> ulnar nerve.
Posterior Compartment of the Forearm
| Brachioradialis | lateral border of distal end of humerus. | superior to styloid process of radius. | elbow flexion; supinates and pronates forearm at radioulnar joints to neutral position. |
| Extensor Carpi Radialis Longus | lateral supracondylar ridge of humerus. | second metacarpal. | extends and abducts hand (radial deviation) at wrist joint. Lesser: elbow flexion, pronation, supination. |
| Extensor Carpi Radialis Brevis | lateral epicondyle of humerus. | third metacarpal. | extends and abducts hand (radial deviation) at wrist joint. Lesser: elbow flexion, pronation, supination. |
| Extensor Digitorum | lateral epicondyle of humerus. | distal and middle phalanges of each finger. | extends distal and middle phalanges of each finger at interphalangeal joints, proximal phalanx of each finger at metacarpophalangeal joint, and hand at wrist joint. Lesser: medial rotation of pinky finger at CMC joint; elbow extension. |
| Extensor Digiti Minimi | lateral epicondyle of humerus | tendon of extensor digitorum on fifth phalanx. | extends proximal phalanx of little finger at MCP, DIP, PIP joints; and hand at wrist joint (wrist extension). Lesser: medial rotation of little finger; elbow extension; ulnar deviation. |
| Extensor Carpi Ulnaris | lateral epicondyle of humerus, and posterior border of ulna. | fifth metacarpal. | extends and adducts hand (ulnar deviation) at wrist joint. Lesser: elbow extension, pronation. |
| Supinator | lateral epicondyle of humerus, and ridge near radial notch of ulna (supinator crest). | lateral surface of proximal 1/3 of radius. | forearm supination. Lesser degree: elbow flexion. |
| Extensor Indicis | posterior surface of ulna. | tendon of extensor digitorum of index finger. | extends distal and middle phalanges of index finger at interphalangeal joints, proximal phalanx of index finger at metacarpophalangeal joint and hand at wrist joint. Lesser: adduction index finger at MCP; supination. |
| Abductor Pollicis Longus | posterior surface of middle of radius and ulna and interosseous membrane. | first metacarpal. | abducts and extends thumb at carpometacarpal joint and abducts hand at wrist joint. Lesser: lateral rotation of thumb at CMC; radial deviation; wrist flexion; supination. |
| Extensor Pollicis Longus | posterior surface of middle of ulna and interosseous membrane. | base of distal phalanx of thumb. | extends distal phalanx of thumb at interphalangeal joint, first metacarpal of thumb at carpometacarpal joint, and abducts hand at wrist joint. Lesser: lateral rotation of thumb at CMC; wrist extension; radial deviation; supination; adduction of thumb at CMC. |
| Extensor Pollicis Brevis | posterior surface of middle of ulna and interosseous membrane. | base of proximal phalanx of thumb. | extends proximal phalanx of thumb at metacarpophalangeal joint, first metacarpal of thumb at carpometacarpal joint, and abducts hand at wrist joint. Lesser: lateral rotation of thumb at CMC; radial deviation. |
Innervated by radial nerve C5-T1.
Muscles that Pronate/Supinate
| Pronator Teres | medial epicondyle of humerus, and coronoid process of ulna. | midlateral surface of radius. | pronates forearm at radioulnar joints and weakly flexes forearm at elbow joint. |
| Pronator Quadratus | distal portion of ulnar shaft. | distal portion of radial shaft. | pronates forearm. |
| Supinator | lateral epicondyle of humerus, and ridge near radial notch of ulna (supinator crest). | lateral surface of proximal 1/3 of radius. | forearm supination. Lesser degree: elbow flexion. |
| Biceps Brachii | short head—corocoid process; long head—tubercle above glenoid cavity on scapula (supraglenoid tubercle). | radial tuberosity of radius, and bicipital aponeurosis. | elbow flexion, supination of radioulnar joint, shoulder flexion. |
Joints
- Distal radio-ulnar: head of ulna, ulnar notch of the radius, triangular ligament.
- Wrist/radiocarpal: radius-scaphoid, lunate; disc of radio-ulnar joint–triquetrum.
Ligaments/Tendons
- Triangular
- Palmar radiocarpal
- Radial collateral
- Ulnar collateral
- Dorsal radiocarpal
Vascular Supply
- Radial artery
- Ulnar artery
- Posterior interosseus artery
- Common interosseous artery
- Anterior interosseous artery
- Perforating branches of anterior interosseous artery
- Superficial palmar branch of radial artery
- Deep palmar arch
- Superficial palmar arch
- Cephalic vein
Innervation
- Median nerve (ventral rami of C5-T1).
- Ulnar nerve.
- Radial nerve C5-T1.
Clinical/Pathology
Other Features
- Cubital fossa
- Extensor retinaculum
- Anatomical snuffbox
Detailed Studies
Notes
References
Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.
Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html
Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.
Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.
