Elbow and Forearm Joints Anatomy PDF

The Elbow And Joints Of The Forearm Topographical & Applied Anatomy What to consider about joints ? Articulations Capsule Ligaments Movements muscles Neurovascular supply Bursae  Articulations Osteology Of humerus: Trochlea Capitulum Olecranon fossa Coronoid...

The Elbow And Joints Of The Forearm Topographical & Applied Anatomy What to consider about joints ? Articulations Capsule Ligaments Movements muscles Neurovascular supply Bursae  Articulations Osteology Of humerus: Trochlea Capitulum Olecranon fossa Coronoid fossa Radial fossa Of ulna: Coronoid process Trochlear notch Olecranon process Of radius: head  Movement - I Elbow is a hinge type synovial joint At full extension the ulna makes an angle of 170º with the humerus (long axis) Note carrying angle  forearm angled further away from the trunk in females Muscles producing hinge movement Biceps brachii Triceps brachii Branchioradialis flexor innervated by radial N.  Capsule – I Weak anteriorly and posteriorly Strengthened by collateral ligaments medially and laterally Elbow and proximal radioulnar joint share a capsule  Capsule - II Synovial membrane lines the fibrous capsule and humerus enclosed by the capsule Ulnar collateral ligament Three bands * Anterior – strongest * Posterior * Oblique - deepens the socket for trochlea Radial collateral ligament * Fanlike * Blends with annular ligament  Bursae There are lots of them! Most give rise to no problems, except… Subcutaneous olecranon bursa Subtendinous olecranon bursa  Nerves at the elbow Radial nerve passes anterior to lateral epicondyle Ulnar nerve passes posterior to medial epicondyle  Neurovasular supply of elbow Hilton’s law Arterial anastomoses formed by collateral arteries and recurrent branches of ulnar, radial and interosseous arteries Radioulnar joints  Proximal radioulnar  Interosseous membrane  Distal radioulnar  Movement – II Pronation / supination involves movement at the elbow and forearm joints Head of radius pivots on capitulum of humerus Proximal radioulnar joint Pivot joint Osteology Of radius:  Head Of ulna:  Radial notch Annular ligament Ligamentous collar Attached to ulna anterior and posterior to its radial notch Pulled elbow Common in children Head of radius subluxates from annular ligament Important definitions / distinctions Dislocation complete loss of contact of the joint surfaces Subluxation partial dislocation of a joint, so that the bone ends are misaligned but still in contact  Interosseous membrane Fibrous joint Fibers run inferomedially allows distribution of force from radius to ulna Distal radioulnar joint Osteology Of ulna Rounded head Of radius Ulnar notch on medial border Articular disk Main structure affording joint integrity Separates cavity of distal radioular joint from wrist cavity  Distal R/U joint in pronation / supination Articular disk ensures joint integrity is maintained Sacciform recess superior extension of synovial capsule allows twisting of the capsule Movement of radioulnar joints Supinator Biceps brachii Pronator quadratus + pronator teres Review Facilitation of supination /pronation function Head of radius and capitulum Annular ligament Sacciform recesses Extensions of the synovial membrane On neck of radius At distal radius and ulna (superiorly from articular disk) The wrist Radiocarpal joint Articulation of distal radius and articular disk with proximal carpal bones Osteology Of radius Distal radius Of carpus Proximal row of carpal bones (other than pisiform), i.e. scaphoid, lunate and triquetrum  Ligaments Collateral ligaments radial & ulnar Palmar radiocarpal ensure hand follow radius during supination Dorsal radiocarpal ensure hand follow radius during pronation Movement at the wrist Flexion / extension Abduction / adduction a.k.a radial deviation / ulnar deviation abduction limited by radial styloid process Fracture of distal radius Colles fracture Posterior displacement of distal fragment of radius Fracture of scaphoid Fall onto outstretched hand Tenderness over anatomical snuffbox Avascular necrosis possible sequela Self-study  Review the osteology of the upper limb  Review joint classification Synovial joints Fibrous joints  Reading from relevant sections from “Clinically Oriented Anatomy” or equivalent