7. Bones of Upper Limb (UL); Vessels & Nerves UL - Part 2 - Forearm and Hand Part 1.pdf

Bones of Upper Limb (UL); Vessels & Nerves of UL - Part 1 Forearm & Hand BiBi Singh, DPM September 16, 2024  Review of the Brachial plexus Describe the muscles of the arm & forearm Identify the joints and ligaments associate...

Bones of Upper Limb (UL); Vessels & Nerves of UL - Part 1 Forearm & Hand BiBi Singh, DPM September 16, 2024  Review of the Brachial plexus Describe the muscles of the arm & forearm Identify the joints and ligaments associated with the Objectives upper extremity Describe the cubital fossa and contents. Explain the brachial artery and its branches Muscles of the Arm – Anterior Biceps Brachii Corachobrachialis Brachialis All are flexors of the arm or forearm All are supplied by the musculocutaneous nerve which then becomes cutaneous to the lateral aspect of the forearm.  Muscles of the Arm - Anterior Muscle Origin Insertion Innervation Blood Supply Action Biceps Brachii Arise from the scapula by 2 heads Posterior part of the Musculocutaneous Muscular Flexor of the Short head – coracoid process tuberosity of the radius nerve branches of the forearm (scapula) Brachial Artery Supinator of the Long head – Supraglenoid tubercle forearm (Scapula)and descends into the Flexor of the arm at intertubercular groove the shoulder joint Corachobrachialis Tip of the coracoid process Middle 1/3 of the medial Musculocutaneous Muscular Flexion o the arm border of the humerus nerve branches of the Adduction of the Brachial Artery arm Brachialis Arise fro the distal 2/3 of the In the capsule of the Musculocutaneous Brachial artery Flexor of the anteromedial and anterolateral elbow joint nerve Radial Recurrent forearm surfaces of the humerus Tuberosity of the ulna Radial Nerve artery Anterior surface of the coronoid process Biceps Tendon Bicipital Aponeurosis – goes across the cubital fossa into the fascia of the forearm and then to the ulna. It offers protection to the underlying neurovascular bundle The biceps tendon itself inserts into the tuberosity of the radius Superficial to the Median nerve and Brachial Artery Bicipital Aponeurosis *Important close relationship The Median Cubital Vein – which connects the Basilic and Cephalic Veins lies superfial * The median cubital vein is frequently used for intravenous injection and blood transfusion Biceps Jerk Observe flexion of the Tapping at the The center of this forearm or twitch of insertion of the bicep reflex is C5 and C6 of the muscle without tendon the spinal cord movement Muscles of the Arm - Posterior Triceps brachii Extensor of the arm and forearm Supplied by the Radial Nerve  Muscles of the Arm - Posterior Triceps Origin Insertion Innervation Blood Supply Action Brachii Long Head Infraglenoid Tubercle of Posterior surface of the Radial nerve Branch of Extensor of the forearm Scapula olecranon Profunda Takes part in throwing, shoveling, *Separates the triangular Deep fascia of the forearm brachii hammering, pushing space from the by the Tricipital aponeurosis If the arm is Abducted, the long quadrangular space head aids in Adducting it. Lateral Head Posterior and lateral Posterior surface of the Radial nerve Branch of Extensor of the forearm surfaces of the humerus olecranon Profunda Takes part in throwing, shoveling, above the groove for the Deep fascia of the forearm brachii hammering, pushing Radial Nerve by the Tricipital aponeurosis Medial Head Posteior surface of the Posterior surface of the Radial nerve Branch of Extensor of the forearm humerus below the groove olecranon Profunda Takes part in throwing, shoveling, for the Radial nerve Deep fascia of the forearm brachii hammering, pushing by the Tricipital aponeurosis Clinical Implications A fracture of the humerus at the middle will damage the radial nerve which is the radial groove of the humeral shaft. Holstein Lewis Fracture It is a simple spiral fracture of the distal humerus with a radial displacement of the distal fragment. These fractures are reported to have a higher rate of radial nerve palsy when compared to other humeral shaft fractures  Tapping the tendon of insertion of the triceps Triceps Jerk Extension of the forearm or twitch without movement The center of this reflex is C6 and C7 of the spinal cord Nerves of the Arm The musculocutaneous and the radial nerves supply muscles of the arm Pass through the arm and do not give branches Ulnar & Median Nerves Pass through the arm and enter the forearm Ulnar, Median & Radial Clinical Implications Ulnar nerve passes the medial epicondyle of the Humeral shaft. A fracture of the epicondyle can damage the nerve. Clinical Pearls - Radial Nerve Located between the Brachioradialis and Brachialis Divides into Superficial branch – becomes cutaneous at the forearm Deep branch – pierces the Supinator muscles Lateral to the Lateral epicondyle. Fracture to the lateral epicondyle will damage the nerve Brachial Artery Continuation of Axillary Artery Relationships: Median nerve lies lateral Radial nerve lies posterior Ulnar and Median antebrachial cutaneous are medial Brachial Artery - Branches Muscular branches Nutrient branches to the Humerus Profunda Brachii Deltoid branches Radial Collateral Artery Middle Collateral Artery Supreme Ulnar Collateral Artery Inferior Ulnar Collateral Artery Clinical Pearl Temporary occlusion, compression, and resumption of blood flow in the brachial artery is the basis for measuring blood pressure with a blood pressure cuff (sphygmomanometer) Cubital Fossa - Boundaries Roof – Superficial Fascia Laterally – Brachioradialis Medially - Pronator Teres Upper Limit – Imaginary horizontal line between the epicondyle of the humerus Floor – Brachialis and Supinator muscles Apex of the Fossa – Neck of the Radius Cubital Fossa - Contents Lateral – Biceps brachii tendon Medial – Median nerve Center – Brachial artery Clinical Pearl A knife wound to the cubital fossa will damage the Median Nerve Muscles of the Forearm Anterior Group – 8 muscles Posterior Groups – 12 muscles Anterior Group - Forearm 5 Superficial Muscles Pronator Teres Flexor carpi radialis Palmaris longus Flexor carpi ulnaris Flexor digitorum superficialis 3 Deep Muscles Flexor digitorum profundus Flexor pollicis longus Pronator quadratus Action : Pronators & Flexion of the wrist and fingers Anterior Forearm – Superficial Muscles Muscle Origin Insertion Innervation Blood Supply Action Pronator Teres Medial supracondylar ridge Middle of the lateral surface of the Radius Median nerve Anterior ulnar Pronates & Flexes the forearm Medial epicondyle recurrent Deep slip from coronoid process of ulna Flexor carpi Arises by the common flexor tendon from Base of 2nd and 3rd metacarpals Median nerve Muscular Flexes the hand radialis the medial epicondyle of the humerus branches of the Steadies the wrist during extension of the radial artery finger Assists in pronating and Abducting the hand Palmaris longus Arises by the common flexor tendon from Anterior to the flexor retinaculum and Median nerve Ulnar recurrent Tenses the palmar aponeurosis the medial epicondyle of the humerus apex of the palmar aponeurosis artery Flexor carpi Arises by the common flexor tendon from Pisiform Ulnar nerve Ulnar recurrent Flexes the hand ulnaris the medial epicondyle of the humerus Hook of the Hamate artery Assists in Adduction of the hand Second head arises from the olecranon and Base of the 5th metacarpal Assists in flexing the forearm posterior border of the ulna Flexor digitorum Humeral head - Arises by the common Anterior surface of the Middle phalanx of Median nerve Muscular Flexes the middle and proximal phalanges superficialis flexor tendon from the medial epicondyle of the medial 4 digits branches of the of the medial 4 digits the humerus Before insertion tendon splits not 2 so the radial & ulnar Aids in flexing the wrist and the forearm Ulnar head – Coronoid process Flexor digitorum profundus passes in artery Radial head – Oblique line of the radius between each split * Tendon passes in Carpal Tunnel  Anterior Forearm – Deep Group Muscle Origin Insertion Innervation Blood Supply Action Flexor Medial and anterior surface of the Distal phalanges of the medial 4 Lateral part: Digits 2 & 3 Muscular Flexes the digitorum ulna digits. Anchored to the phalanx by a – Anterior interosseous branches from : terminal profundus Interosseus membrane fibrous material called vincula nerve ( branch of the ulnar & anterior phalanges of Deep fascia of the forearm * Tendon passes in Carpal Tunnel median nerve) interosseous the medial 4 Each tendon is enclosed by Medial part: Digits 4&5 artery digits Flexor digitorum superficialis – Ulnar nerve Aids in flexing tendon the wrist Flexor pollicis Anterior surface of the radius Palmar aspect of the distal phalanx Anterior interosseous Anterior Flexes the longus Interosseus membrane of the thumb nerve interosseous thumb Medial border of the coronoid *Tendon passes in Carpal Tunnel artery process of the ulna Pronator Anterior surface of the distal part of Anterior surface of the lower 1/3 of Anterior interosseous Anterior Prontaes the quadratus the ulna, passes laterally the radius nerve interosseous forearm artery Question to Ponder All of the following tendons pass through the Carpal Tunnel, EXCEPT: a. Palmaris longus b.Flexor digitorum superficialis c.Flexor digitorum profundus d. Flexor pollicis longus Ans: A Structural Classification of Joints Fibrous: No joint cavity, joints held together by fibrous connective tissue. Cartilaginous: No joint cavity, joint held together by cartilage Synovial: There is a joint cavity; bones are united by a surrounding articular capsule; accessory ligaments are frequently present Functional Classification of Joints Synarthrosis: Immovable joint Suture – Unite skull bones Gomphosis – Tooth in socket Synchondrosis – True ribs and sternum Amphiarthrosis: Slightly movable joint Syndesmosis – distal tibia fibula Symphysis – Intervertebral joints Diarthrosis: Freely movable joint Ball and Socket Joint( Spheroid Joint) - Hip Ellipsoidal Joint(Condyloid Joint) – Metacarpophalangeal joint Gliding Joint (Arthrodial Joint) – Navicular and 2nd and 3rd cuneiforms Hinge Joint (Ginglymus Joint) – Interphalangeal joint Pivot Joint(Trochoid Joint) - Elbow Saddle Joint (Sellaris Joint) – Trapezium and the thumb Diarthrosis Synovial joints with distinguishing anatomical features: Synovial joint cavity – a cavity that separates articulating bones Articular cartilage – A hyaline type cartilage that covers the bone surfaces of the joint Articular capsule – a sleeve-like structure that encloses the synovial cavity and unites the articulating bones: composed of 2 layers, the outer fibrous capsule and inner synovial membrane ( secretes synovial fluid to lubricate the joint. Joint Classification Glenohumeral Joint Diarthrosis Ball and Socket Joint( Spheroid Joint) Sternoclavicular Joint Diarthrosis Saddle joint (Sellaris Joint) Joint Classification Elbow Joint Diarthrosis Hinge Joint (Ginglymus Joint) Proximal Radio – Ulnar Joint & Distal Radio – Ulnar Joint Diarthrosis Pivot (Trochoid Joint) Question to Ponder All the muscles of the forearm are supplied by the median nerve and its branch, the anterior interosseous nerve. Name two muscles supplied by the ulnar nerve (Be specific): Flexor digitorum profundus – medial – 4th & 5th digits Flexor carpi ulnaris