ANAT 241 - Lecture 23 (Elbow, Wrist and Hand) PDF

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Elbow Joint:  The Function of the Elbow Joint is for the attchement of the Forearm (Antebrachium) to the Arm (Brachium) and insertion sites for ligaments for stabillity and tendons for mobillity  The Elbow Joint is a Hinge Joint located between the Distal Humerus and Proximal Radius and Proximal Ulna which allows flexion and extension  The Coronoid Process Resticts excessive movement  The Radius and Ulna are connected by an Interosseus Membrane

Proximal Radio-Ulna Joint:  The Proximal Radio-Ulna Joint is a Synovial Pivot Joint located between the Radial Notch of the Proximal Ulna and the Radial Head of the Proximal Radius which allows supination and pronation.  The Annular Ligament originates from the Ulna and surrounds the Circular Head of the Radius  The Quadrate Ligament connects the inferior border of the Radial Notch of the Ulna to the Radial Neck  The Oblique Ligament connect the Radial Tuberosity and Ulna Tuberosity  The Annular Ligament is lax in children and often detaches in Yanking Movements called Milkmaids Elbow

Distal Radio-Ulna Joint:  The Proximal Radio-Ulna Joint is a Synovial Pivot Joint located between the Ulna Head at the Distal Ulna and the Ulna Notch of the Radius at the Distal Radius Ulna which allows supination and pronation.  The Palmar Radio-Ulna Ligament connect the Ulna Head at the Distal Ulna and the Ulna Notch of the Radius at the Distal Radius Ulna on the Anterior Surface  The Dorsal Radio-Ulna Ligament connect the Ulna Head at the Distal Ulna and the Ulna Notch of the Radius at the Distal Radius Ulna on the Posterior Surface Wrist (Radiocarpal Joint):  The Wrist (Radiocarpal Joint) is a Synovial Ellipsoid Joint located between the Articular Facets of the Distal Radius and the Scaphoid and Lunate Proximal Carpal Bones which allows Flexion/ Extension, Abduction/ Adduction and Circumduction  The Articular Disk/ Triangle is made from Fibrocartilage and is located between the Radius, Ulna and Carpal Bones on the Medial aspect of the wrist  Both the Distal Radius and Distal Ulna have Styloid Processes Carpal Bones:  There are 4 Proximal Carpal Bones and 4 Distal Carpal Bones  The Mnemonic is “Sally Left The Party” “To Take Chris Home” from Lateral to Medial and Proximal to Distal  The “Trapezium is under the Thumb and the Trapezoid is right besoid” Lateral: Middle: Medial: Proximal Row: Scaphoid Lunate Triquetral Pisiform Distal Row: Trapezium Trapezoid Capitate Hamate Carpal Tunnel:  The Carpal Tunnel is a Flexor Reticulum located between the Trapezium (lateral) and the Pisiform (Lateral) and Humulus of the Hamate (Lateral) which encloses blood vessels and nerves  Carpal Tunnel Syndrome is due to the excessive use of Wrist Flexors causing inflammation which compresses the Median Nerve causing Numbness and Pain. Hand:

 The function of the hand is for manipulation, sensation and interaction with the environment  The Thumb is called the Pollux  There are 5 Metacarpals per hand (1 for each digit)  There are 3 Phalanges per Digit and 2 Phalanges for the Pollux (Thumb) Joint: Description: Carpo-metacarpal Joint (1): Synovial Saddle Joint for Thumb Oppostion Carpo-metacarpal Joint (2-5) Synovial Plane Joint Metacarpo-Phalangeal Joint: Synovial Condylar Joint Inter-Phalangeal Joint: Synovial Joint

Muscles: Forearm Flexors: Muscle: Biceps Brachii (*)

Brachialis:

Origin: Long Head (LH): Supraglenoid Tubercle of the Scapula Short Head (SH): Coracoid Process of the Scapula Mid shaft of the Anteromedial Humerus Mid shaft of the anterolateral humerus

Insertion: Radial Tuberosity

Function: Forearm Flexion Forearm Supination (At the Radioulnar Joint) Arm Flexion

Ulnar tuberosity

Forearm flexion strong

Insertion: Ulnar Olecranon

Function: Forearm Extension Arm Extension (Long Head only = weak)

Forearm Extensors: Muscle: Triceps Brachii (*)

Origin: Long Head (LH): Infraglenoid Tubercle of the Scapula Medial Head (MH): Posterior Humorous Lateral Head (lH): Posterior Humorous

Supinators and Pronators: Supinators: Biceps Brachii Supinator

Muscles of the Wrist and Hand:

Pronators: Pronator Teres Pronator Quadratus

 Extrinsic Muscles are for grip, lifting, writing and grabbing  Intrinsic Muscles and Lumbricals are for grip, precise movement and control of digits  Extrinsic Flexors are located in the Anterior compartment and Extrinsic extensors are located in the posterior compartment  Intrinsic Muscles include Thenar, Hypothenar and Interossei  Lumbricals have no bony origin which are used for Metacarpophalangeal Flexion and Interphalangeal Extension Biceps Brachii:

Brachialis:

Triceps Brachii:...