MSAK 1 Lecture Ulna, Radius & Hand Bones PDF

Unit 1: Lecture 4 of 8 Ulna, Radius & Hand Bones MSAK 1 Lecture Laurence Muir Readings: T&D: sections 8.2 Netter...

Unit 1: Lecture 4 of 8 Ulna, Radius & Hand Bones MSAK 1 Lecture Laurence Muir Readings: T&D: sections 8.2 Netter Plates Course notes are created for exclusive use at WCCMT Victoria.  LESSON OBJECTIVES ❑List the bones of the forearm, wrist, and hand ❑Describe the Radius and its’ key landmarks ❑Describe the Ulna and its’ key landmarks ❑List the order of the 8 carpal bones ❑Describe the remaining 19 bones of the hand Course notes are created for exclusive use at WCCMT Victoria.  Radius and Ulna 2 Bones of the forearm Radius is on the lateral (thumb) side Ulna is on the medial (pinky) side Assist in positioning the hand Pivoting of the radius allows for pronation + supination movements at the proximal and distal radioulnar joints Course notes are created for exclusive use at WCCMT Victoria.  Radius and Ulna ▪ Radius is the smaller of the 2 bones ▪ Proximal end is narrower ▪ Distal end in wider ▪ Ulna is the longer of the 2 bones ▪ Proximal end is wider ▪ Distal end in narrower ▪ Shafts of both bones are essentially triangular on cross section Course notes are created for exclusive use at WCCMT Victoria.  Ulna ▪ Medial stabilizing bone of forearm ▪ Remains stationary during pronation/supination ▪ Larger proximal end forms the elbow (olecranon) ▪ Shaft (triangular) ▪ 3 borders ▪ Anterior/volar ▪ Posterior/dorsal ▪ Interosseous ▪ 3 surfaces ▪ Anterior/volar ▪ Posterior/dorsal ▪ Medial Course notes are created for exclusive use at WCCMT Victoria.  Proximal Ulna ▪ Olecranon process ▪ Fits into olecranon fossa of posterior humerus ▪ Coronoid process ▪ Fits into coronoid fossa of humerus ▪ Trochlear/semilunar notch ▪ Articulates with trochlea of humerus ▪ Radial notch ▪ Articulates with radial head Course notes are created for exclusive use at WCCMT Victoria.  Proximal Ulna ▪ Ulnar (brachial) tuberosity ▪ Brachialis insertion ▪ Supinator crest ▪ Inferior to ulnar tuberosity ▪ Supinator muscle attachment ▪ Supinator fossa ▪ Interosseous border (ridge, crest) Course notes are created for exclusive use at WCCMT Victoria. ▪ Sharp lateral edge of ulnar shaft  Interosseous Membrane ▪ Fibrous joint ▪ Syndesmosis ▪ Amphiarthrotic ▪ Divides the forearm into anterior and posterior compartments ▪ Serves as muscle attachment site ▪ Transmits loads/forces Course notes are created for exclusive use at WCCMT Victoria.  Ulna Course notes are created for exclusive use at WCCMT Victoria.  Distal Ulna ▪ Narrower ▪ Rounded head articulates with the ulnar notch of the radius ▪ Styloid process ▪ Ulnar collateral ligament Course notes are created for exclusive use at WCCMT Victoria.  See it Feel it What bony landmarks are found Say it Do it on the ULNA? Teach it Course notes are created for exclusive use at WCCMT Victoria.  Radius ▪ Located on the thumb (lateral) side of the forearm ▪ Moves during pronation/supination ▪ Circular (disc-shaped), proximal end covered with articular cartilage (hyaline) ▪ Distal end: biconcave, triangular, covered with hyaline cartilage. Articulates with 2 carpal bones Course notes are created for exclusive use at WCCMT Victoria.  Radius ▪ Head ▪ Neck ▪ Radial (bicipital) tuberosity ▪ biceps insertion ▪ Styloid process ▪ lateral side of distal end ▪ Shaft (triangular) ▪ 3 borders ▪ Anterior ▪ Medial (interosseous) ▪ Posterior ▪ 3 surfaces ▪ Anterior ▪ Posterior ▪ Lateral Course notes are created for exclusive use at WCCMT Victoria.  Radius: Proximal End ▪ Head ▪ Articular Fovea ▪ Superior surface of radial head ▪ Deep, concave fossa that articulates with the capitulum of the humerus ▪ Circumferential articulation (articular edge of radial head) ▪ Articulates with radial notch of ulna Course notes are created for exclusive use at WCCMT Victoria.  Radius Pronator tubercle pronator teres muscle middle of the lateral surface Interosseous border (ridge, crest) Sharp medial edge of radial shaft Course notes are created for exclusive use at WCCMT Victoria.  Radius: Distal End ▪ Dorsal (Lister’s) tubercle ▪ Palpable on dorsum of the wrist ▪ Groove on ulnar side acts as a pulley, redirecting pull of the extensor pollicis longus tendon ▪ Styloid process ▪ Insertion of brachioradialis ▪ Radial collateral ligament ▪ Ulnar/sigmoid notch ▪ Distal radioulnar joint Course notes are created for exclusive use at WCCMT Victoria.  See it Feel it Say it Do it What bony landmarks are found Teach it on the RADIUS? Course notes are created for exclusive use at WCCMT Victoria.  Carpals ▪ Most proximal region of the hand ▪ Short bones of the wrist ▪ 8 total ▪ 2 rows of uniquely shaped bones Course notes are created for exclusive use at WCCMT Victoria.  Carpals: Proximal Row ▪ Scaphoid ▪ Largest of proximal row ▪ Distal to radial styloid ▪ Boatlike ▪ Tubercle ▪ Transverse carpal ligament ▪ Most frequently fractured carpal bone ▪ Lunate ▪ Moon-shaped ▪ Most frequently dislocated bone of the wrist ▪ Triquetrum ▪ Three-cornered ▪ Pisiform ▪ Pea-shaped ▪ Sesamoid bone within flexor carpi ulnaris tendon Course notes are created for exclusive use at WCCMT Victoria.  Carpals: Distal Row ▪ Trapezium ▪ Tubercle for abductor pollicis brevis ▪ Floor of “anatomical snuff box” along with the scaphoid ▪ Trapezoid ▪ Difficult to palpate ▪ Capitate ▪ Axis of motion for radial/ulnar deviation goes through it ▪ In line with middle finger ▪ Found in a slight depression on dorsum of the wrist ▪ Head-shaped ▪ Hamate ▪ Hook of hamate on palmar surface ▪ Forms part of Guyon’s/ulnar canal Course notes are created for exclusive use at WCCMT Victoria.  Mnemonic for Carpals “Some Lovers Try Positions That They Can’t Handle” Lateral to medial, and proximal to distal Course notes are created for exclusive use at WCCMT Victoria. Course notes are created for exclusive use at WCCMT Victoria.  Metacarpals ▪ 5 total ▪ Numbered I, II, III, IV, V Course notes are created for exclusive use at WCCMT Victoria.  Metacarpals ▪ Base (proximal) ▪ Shaft/body ▪ Concave medial/lateral and palmar ▪ Head (distal) ▪ Articulate proximally with distal row of carpals ▪ Articulate distally with phalanges Course notes are created for exclusive use at WCCMT Victoria.  Phalanges ▪ 14 total ▪ Thumb has 2 phalanges ▪ Proximal and distal ▪ Other fingers have 3 phalanges ▪ Proximal ▪ Middle ▪ Distal ▪ Base (proximal) ▪ Body (intermediate) ▪ Head (distal) Course notes are created for exclusive use at WCCMT Victoria.  Surface Anatomy Course notes are created for exclusive use at WCCMT Victoria.  Sesamoids ▪ Develop in tendons at the ends of long bones ▪ Protect tendons from excessive friction ▪ Can change the angulation of the tendon for mechanical advantage ▪ Some are normal ▪ patella ▪ Some are normal variants (may or may not be present) ▪ os fabella in calf muscle Course notes are created for exclusive use at WCCMT Victoria.  Sesamoids ▪ Most people have 5 sesamoids in the hand ▪ 2 in the thumb at the MCP joint ▪ Most common ▪ Flexor pollicis brevis tendon ▪ Adductor pollicis tendon ▪ 1 in interphalangeal joint of thumb ▪ 1 at radial side of index finger MCP joint ▪ 1 at ulnar side of MCP of little finger Course notes are created for exclusive use at WCCMT Victoria.  See it Feel it Say it Can you name all the bones of the hand? Do it Teach it Course notes are created for exclusive use at WCCMT Victoria.  LESSON OBJECTIVES ❑List the bones of the forearm, wrist, and hand ❑Describe the Radius and its’ key landmarks ❑Describe the Ulna and its’ key landmarks ❑List the order of the 8 carpal bones ❑Describe the remaining 19 bones of the hand Course notes are created for exclusive use at WCCMT Victoria.