Upper limb 1 Flashcards
What is the axial skeleton?
Consists of the bone of the head and trunk of a vertebrae; including all the bones that form bony structures along the body’s long axis
What is the appendicular skeleton?
Portion of the skeleton of vertebrates consisting of bones that support the appendagesThe appendicular skeleton includes the skeletal elements within the limbs (Upper and lower), as well as supporting shoulder, pectoral and the pelvic girdles
What is the main function of the upper limb?
Manipulation and grip activities
Which is joint is the only attachment of the upper limb of the axial skeleton?
Sternoclavicular joint
What are the ends of the sternoclavicular joint?
Sternal end of the clavicle,
Manubrium of the sternum
Part of the 1st costal cartilage
What type of cartilage covers the articular surfaces of the sternoclavicular joint?
Fibrocartilage
Which three bones form the pectoral girdle?
Humerus, scapula, clavicle
Which structures does the clavicle articulate with medially?
Manubrium of the sternum
Which structure does the clavicle articulate with laterally?
Acromion
Which bone forms the arm?
Humerus
Which joint does the humerus articulate with, at the forearm?
Elbow joint
What two main actions are possible at the elbow joint?
Extension
Flexion
Which two bones form the forearm?
Radius
Ulnar
Which forearm bone is lateral?
Radius
Which forearm bone is medial?
Ulna
What three bone types form the hand?
Carpal bones
Metacarpal
Phalanges
Which bone is the only attachment between the trunk and the upper limb?
Clavicle
What are the two ends of the clavicle?
Acromial end
Sternal end
What is the sternal end of the clavicle?
Larger facet for articulation with the thoracic wall of the trunk at the manubrium of the sternum
Which joint of the scapula articulates with the humerus?
Glenohumeral
Which joint does the clavicle articulate with, with the scapula?
Acromioclavicular joint
Which two fossa’s form the posterior aspect the scapula?
Supraspinous
Infraspinous
How is the supraspinous and the infraspinous fossa’s divided?
Divided by the scapular spine
Which scapular structure is continuous with the acromion?
Scapular spine
Which fossa does the head of the humerus articulate with?
Glenoid fossa
Which structures does the humerus articular with distally?
Head of the radius, and the trochlear notch of the ulna
Which tubules are found on the proximal humeral head?
Lesser and greater tubercles
What sulcus run between the two tubercles of the humerus?
Inter-tubercular sulcus
Where is the greater tubercle located on the humerus?
Laterally of the head
Describe the location and surfaces of the greater tubercle of the humerus?
Laterally on the humerus, consists of anterior and posterior surfaces,
What is the function of the greater tubercle of the humerus?
Provides an attachment site for the three rotator cuff muscles: Supraspinatus, infraspinatus, teres minor
Where do the supraspinatus, infraspinatus and teres minor attach too?
To the superior middle and inferior facets respectively on the greater tubercle
Where is the lesser tubercle of the humerus located?
Located medially at the head of the humerus
Which rotator cuff muscle has an attachment to the lesser tubercle of the humerus?
Subscapularis
Which tendon emerges from the shoulder joint and runs through the interturbercular sulcus?
Long head of the biceps brachii
What is the purpose of the lateral humerus shaft and the deltoid tuberosity?
Provides point of attachment fo the deltoid muscle
What are the distal humeral projections?
The medial and lateral epicondyles
Where does the ulna bone reside?
Resides medially and parallel to the radius, acts as a stabilising bone, with the radius pivoting to produce movement
What does the ulna articulate with at its proximal end?
Articulates with the trochlea of the humerus; enables movement at the elbow joint, the ulna has a specialised structure with bony projections for muscle attachment
What does the distal end of the ulna bone terminate with?
The ulnar styloid process. the head articulates with the ulnar notch of the radius, forming the distal-radio ulnar joint
Where does the radius bone reside?
lies laterally and parallel to the ulna. Radius pivots around the ulna to produce movement at the proximal end and distal-radio ulnar joints
What is the purpose of the radial tuberosity?
Bony projection serves as a place of attachment of the biceps brachii muscle
What forms the elbow joint?
Formed by an articulation between the head of the radius, and the capitulum of the humerus
What is the proximal radioulnar joint?
Articulation between the radial head and the radial notch of the ulna
What is the wrist joint?
Articulation between the distal end of the radius and the carpal bones
What is the distal-radioulnar joint?
Articulation between the ulnar notch and the head of the ulnar
What fibrous connective tissue connects the radius and ulna?
Interosseous membrane
How many carpal bones are there?
Set of eight bones
How many metacarpals exist?
1-5
How many phalanges form the digits (2-5)?
3
How many phalanges comprise the thumb?
2
Describe function of the carpometacarpal joint?
Increased flexibility, provides opposition of the thumb to the fingers
What are three bones that form the proximal row of the carpal bone?
Scaphoid
Lunate
Triquetrum
Which is a sesamoid bone?
Pisiform bone
Which four carpal bones form the distal row?
Trapezium, trapezoid, capitate, and hamate
Which arch is formed by the carpal bone?
Carpal tunnel
Which membranous band spans between the medial and lateral arches of the carpal arch?
Flexor retinaculum
Where do the metacarpal bones articulate with proximally?
Articulate with the carpals
Where do the metarcarpal bones article with distally?
Distally with the proximal phalanges
Which muscles attach to the medial and lateral surfaces of the metacarpals?
Interossei muscles
What are fibrous joint?
Bones connected by fibrous tissue (sutures)
What are sutures?
Immovable joints (synarthrosis)
What are cartilaginous joints?
Bones connected with cartilage
What are primary joints?
Synchondrosis, connected by hyaline cartilage; epiphyseal plates are temporary cartilaginous joints that enables bone growth
What are secondary cartilagunous joints?
Symphysis, connected by fibrocartilage, mainly in the midline of the body
What are synovial joints?
Articulation surrounded by an enclosing synovial capsule, bones not directly connected at the joint surfaces
What are uniaxial synovial joints?
Movement is exclusively in one direction (hinge joint)
What are biaxial synovial joints?
Movement in two different planes (saddle joint)
What are multiracial joints?
Movement on several axes, ball and socket joint
What type of joint is the thumb?
Saddle joint
Describe the mobility of a synarthrosis joint?
Minimum-none mobility (Fibrous joints, including sutures).
Describe the mobility of a amphiarthrosis joint?
Restricted mobility
Describe the mobility of a diarthrosis joint?
Dextrously mobile (Majority of joints, mainly synovial).
Name the 6 types of synovial joints?
Hinge Saddle Plane Pivot Condyloid Ball and socket
What are hinge joints?
Permits movement in one plane- flexion and extension (Elbow joint, ankle and knee joint).
What are saddle joints?
Saddle: Named due to its resemblance to a saddle; characterised by opposing articular surfaces with a reciprocal concave-convex shape (carpometacarpal joint).
What are plane joints?
Articular surfaces are relatively flat, enabling the bones to glide over one another (Acromioclavicular and subtalar joint).
What are pivot joints?
Enables rotation only. Formed by a central bony pivot, surrounded by a bony ligamentous ring (Proximal and distal radioulnar joints, atlantoaxial joint).
What are condyloid joints?
Contains a convex surface which articulates with a concave elliptical cavity. (Wrist joint, metacarpophalangeal joint, metatarsophalangeal joint).
What are ball and socket joints?
Ball-shaped surface of one rounded bone fits into the cup-like depression of another; enabling free movement in numerous axes (Hip joint, shoulder joint).
What is the principle of mobility and stability?
Principle of mobility and stability: The more moveable a joint is, the more unstable it becomes. The shape of the articulating part of the bones would provide insufficient support and independent stability.
What effect do ligaments have on mobility?
Ligaments reduce the possibilities for movement, and is significantly restricted. This prevents unwanted movements that would subsequently destabilise a joint.
What is a retinaculum?
Retinaculum is thickened band of deep fascia found close a joint. This band holds tendons down during muscle contraction to prevent bow-stringing, which might compromise function.
What is an aponeurosis?
Flat, sheet resembling structure derived from a tendon or ligament
Aponeuroses provides a broad attachment for a muscle which will distribute mechanical load over a relatively larger area in comparison to a standard tendon
Provides protection for underlying structure
What is a bursa?
A bursa is a closed sac of a serous membrane, resembling an interior similar to that of synovial joints. Delicate membranes of bursae secrete a lubricating fluid to their interior. Bursae are found at sites subjected to friction, behaving as a bearing to enable free unrestricted movement; facilitate gliding motion.
Bursitis (inflammation) is extremely painful.
What is the sternoclavicular joint?
Occurs between the proximal end of the clavicle and the clavicular notch of the manubirum of the sternum
What type of synovial joint is the sternoclavicular joint?
Synovial joint and saddle shaped
Articular cavity is separated into two compartments by an articular disc. The sternoclavicular facilitates movement of the clavicle, predominantly in the anteroposterior and vertical planes.
What is the interclavicular ligament?
Links the ends of the two clavicles to each other, and to the superior surface of the manubrium of the sternum
What is the costoclavicular ligament?
Positioned laterally to the joint and links the proximal end to the first rib and related cartilage
Which muscles elevate the scapulothoracic joint?
Superior trapezius
Levator scapulae
Rhomboids
Which muscles depress the scapulothoracic joint?
Inferior trapezius
Pectoralis minor
Serratus anterior
Which muscles protract the scapulothoracic joint?
Pectoralis minor, and serrates minor
Which muscles retract the scapulothoracic joint?
Rhomboids
Middle trapezius
Latissimus dorsi
Which muscles rotate the scapulothoracic joint?
Glenoid fossa faces upwards and downwards as scapula rotates
Which muscles flex the glenohumeral joint?
Pectoralis major
Anterior deltoid
Which muscle extends the glenohumeral joint?
The posterior deltoid
Which muscle abducts the glenohumeral joint?
Supraspinatus initially, then the central deltoid
Which muscle adducts the glenohumeral joint?
Pectoralis major, lattisimus dorsi
Which muscle is responsible for the internal reaction of the gleno-humeral joint?
Subscapularis
Which muscle is responsible for the external rotation of the glenohumeral joint?
infraspinatus
How is the glenohumeral joint stabilised?
Joint stability is provided by the rotator cuff muscles attached to the greater tubercle of the humerus, the long head of the biceps brachii muscle, and extra capsular ligaments
What cartilage lines the large spherical head of the humerus, and glenoid cavity?
Hyaline cartilage
What stabilises the glenoid cavity?
Glenoid labrum
What does the ulna articular with at the elbow joint?
Trochlea notch of the ulna
Trochlea of the humerus
What does radius articulate with at the elbow joint?
Head of radius articulates with the capitulum of the humerus
What are the two functions of the elbow joint?
Extension and flexion
What functions are provided at the proximal radioulnar joint?
Pronation and supination
Which fossa is associated with the capitulum?
Radial fossa
Which fossa is associated with the ulnar?
Coronoid fossa
Which fossa is evident when fully extended?
Olecranon fossa
Which carpal bones articulate with the distal end of the radius?
Proximal row
Scaphoid, lunate and triquetrum bones
What does the distal end of the ulna articular with?
Articulates with the articular disc
What type of joint is the radoiocarpal joint?
Biaxial
What are inter carpal joints?
Articulation between the carpal bones and the proximal & distal rows
What are carpal-metacarpal joints?
Articulates between the distal row of the carpal bones and the basis of metacarpals
Synovial plane joints with the exception of the first carpal-metacarpal joint- saddle joint
What is the metacarpo-phalangeal joint?
The articulations between the metacarpals and phalanges are the metacarpophalangeal joints (Visible in the knuckles)- synovial condylar joints, enabling a wide range of movement (Restricted by ligaments).
What are interphalngeal joint?
Articulation between the phalanges are the interphalangeal joints. Synovial hinge joints are capable of flexion and extension. Ligaments (collateral) connect phalanges at the lateral and medial sites.
What is the action of the Rhomboids?
Steadies the scapula, moves inferior angle backward and upward
What is the action of the latissimus dorsi?
Medial rotation, adduction, extension and respiration
What forms the lateral border of the cubital fossa?
Brachioradialis
What forms the medial border of the cubital fossa?
Pronator teres
What forms the superior border of the cubital fossa?
The line between the humeral epicondyles
What forms the floor of the cubital fossa?
Brachialis and supinator muscle biceps
Where does the brachial artery birfucate?
Bifurcates in the cubital fossa into the radial and ulnar arteries
Which nerves are found within the floor of the cubital fossa?
Median and radial nerve (deep branch)
Which veins and nerve form the forearm?
Medial cubital vein
Lateral and medial cutaneous nerves of the foream
Which fascia is found within the cubital fossa?
Superficial fascia
Deep fascia refinanced by bicipital aponeurosis
What are the three main muscles of the pectoral girdle?
Serrates anterior
Pectoralis major
Pectoralis minor
What is the distal attachment of the pectoralis major?
Intertubercular sulcus of the humerus
Where does the sternocostal head originate of the pectorals major?
Originates from the anterior surface o fat sternum, the superior six costal cartilage s and aponeurosis of the external oblique muscle
What is the function of the pectoralis major?
Adducts and medially rotates the upper limb, draws the scapula anterioinferiorly
Which nerve innervates the pectoralis major?
Lateral and medial pectoral nerves (branches of the brachial plexus)
Which muscle is situated between the ribs and scapula at the upper and lateral regions of the chest?
Serrates anterior
What is the origin of the serratus anterior?
8-9 ribs
Which nerve innervates the serratus anterior?
Long thoracic (C5-C7)
What is the action of the serratus anterior?
Protracts scapula, upwards rotation (glenoid cavity moves superior); holds scapula close the thoracic wall; elevates ribs when scapula is fixed
What is the superficial muscle residing around the glenohumeral joint?
Deltoid muscles
What are the three deltoids?
Anterior, middle, posterior
What is the origin of the anterior deltoid?
Lateral third of the clavicle
Where does the anterior deltoid insert?
Deltoid tuberosity, on the later side of the body of the humerus
Which nerve innervates the deltoid?
Axillary nerve
What is the action of the anterior deltoid?
Flexion
Medial rotation of the humerus
What is the origin for the middle deltoid?
Acromion
Where does the middle deltoid insert?
Deltoid tuberosity of the lateral side of the body of humerus
What is the action for the middle deltoid?
Abduction of the humerus
Where does the posterior deltoid originate from?
Scapular spine
Where does the posterior deltoid insert?
Deltoid tuberosity of the lateral side of the humerus
What is the action of the posterior deltoid?
Extension and lateral rotation of the humerus
Where does the Teres major originate from?
From the posterior surface of the inferior angle of the scapula
Where does the teres major insert?
Intertubercular groove of the humerus
What is the action of the teres major?
Extension, adduction and medial rotation of the humerus
What are the four rotator cuff muscles?
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
What is the main function the rotator cuff muscles?
Attach to the humeral head, collectively, the rating tone of these muscles acts to pull the humeral head into the glenoid fossa = additional stability of the glenohumeral joint
What is the origin for the supraspinatus?
Supraspinatus fossa
Where does the supraspinatus muscle insert?
Greater tubercle of the humerus
Which nerve innervates the supraspinatus?
Suprascapular nerve
What is the action of the supraspinatus?
Assist deltoid in abducting the arm, stabilises the glenohumeral joint
What is the origin of the infraspinatus?
Infraspinatus fossa on posterior surface of the scapula
Where does the infraspinatus insert?
Greater tubercle of the humerus
What is the action of the infraspinatus muscle?
Laterally rotates the upper limb, stabilises the glenohumeral joint
What is the origin of the teres minor?
Lateral border of the scapula
Where does the teres minor insert?
Greater tuberosity of the humerus
Which nerve innervates the teres minor?
Axillary nerve
What is the action of the teres minor?
Lateral rotation of the humerus, stabilisation of the shoulder joint
What is the origin of the subscapularis?
Originates from the subscapular fossa
What is the insertion of the subscapularis?
Lesser tubercle of the humerus
Which rotator cuff muscle has an insertion of the lesser tubercle of the humerus?
Subscapularis
What is the action of the subscapularis?
Medial rotation of the head of the humerus; prevents anterior displacement of the humerus.
Where does the bicep tendon enter there forearm?
The bicipital aponeurosis , roof of the cubital fossa
Which artery supplies the biceps?
Brachial artery
What is the origin of the long head of the biceps brachii?
Supraglenoid tubercle of the scapula
Where does the long head of the biceps brachii insert?
Radial tuberosity & bicipital aponeurosis
Which nerve innervates the biceps?
Musculocutaneous nerve
What is the function of the biceps?
Supination and flexion of the arm, at shoulder and elbow
Where does the short head of the biceps brachii originate from?
Coracoid process of the scapula
Where does the short head insert?
Radial tuberosity
What is the brachialis muscle?
Flexor muscle of the elbow joint, resides within the anterior aspect of the elbow, low half of the humerus. The muscle lies deep to the biceps brachii, and is found distally to the humerus, forms floor of the cubital fossa
Where does the brachialis originate from?
Medial and lateral surface of the humeral shaft
Where does the brachialis muscle insert into?
Ulnar tuberosity and anterior surface of the coronoid process
What is the function of the brachialis?
Flexes forearm at the elbow
Which nerve innervates the brachilias?
Musculocutaneous nerve
Branch from the radial nerve
What is the origin of the coracobrachialis?
Coracoid process of the scapula muscle passes through the axilla
What is the insertion of the coracobrachialis?
Medial surface and border of the body of humerus, at the level of the deltoid tubercle
What is the action of the coracobrachialis?
Adduction and flexion of humerus; assist with retaining the head of the bone in contact with the glenoid cavity.
Which nerve innervates the coracobrachialis?
Musculocutaneous nerve
What are the triceps?
Posterior compartment of the upper arm consists of the triceps brachii muscle (3 heads); the medial head resides deeper than the long and lateral heads. The triceps is situated on the back of the arm, and extends the entire length of the dorsal humerus surface.
What is the function of the triceps?
Extends the forearm at the elbow joint
Where do the triceps insert?
Olecranon of the ulna
Which nerve innervates the triceps?
Radial nerve
Where does the flexor carpi ulnas originate?
Medial epicondyle of the humerus, and the olecranon of the ulna
What is the insertion of the flexor carpi ulnaris?
Pisiform bone
Hook of hamate, base of metacarpal 5
What is the main function of the flexor carpi ulnaris?
Flexes, adducts the hand (Ulnar deviation)
Which nerve innervates the flexor carpi ulnaris?
Ulnar nerve
Where does the palmaris tongue originate from?
Medial epicondyle of the humerus
Where does the palmaris longs insert?
Palmar aponeurosis and flexor retinaculum
What is the action of the palmaris longus?
Flexes hand at risk, tenses flexor retinaculum
Which nerve innervates the palmaris longus?
Median nerve
Where does the flexor carpi radialis originate from?
Medial epicondyle of the humerus
What is the insertion of the flexor carpi radialis?
Base of the 2nd metacarpal and base of the 3rd metacarpal
Which nerve innervates the flexor carpi radialis?
Median nerve
What is the action of the flexor carpi radialis?
Flexion and abduction (radial) of the hand
Where does the pronator teres originate from?
Medial epicondyle of humerus; and coronoid process of the ulna
What is the insertion of the pronator teres?
Attaches laterally to the mid shaft of the radius
What is the action of the pronator teres?
Pronation of the forearm
Which nerve innervates the pronator teres?
Median nerve
Where does the flexor digitorum superficialis originate from?
Two heads; medial epicondyle of the humerus, and coronoid process, radial head
Where does the flexor digitorum superficialis insert?
Middle phalanx of digits 2-5
Which nerve innervates the flexor digtitorum superficialis?
Median nerve
What action is performed by the flexor digitorum superficialis?
Flexes wrist, flexes middle and proximal phalanges of digits (2-5)
Where does the Flexor digitorum profundus originate from?
From the ulna, and proximal thee fourths of the anterior & medial surfaces of the ulna and the interosseous membrane
Where does the Flexor digitorum profundus insert?
Base of the palmar surface of the distal phalanges (2-5)
Which nerve innervates the Flexor digitorum profundus?
Interosseous branch of the median and ulnar nerves
What is the action of the Flexor digitorum profundus?
Flexes wrist, flexes distal phalanx of digits 2-5
Where does the flexor pollicis longus originate from?
Anterior surface of radius and interosseus membrane
Where does the flexor pollicis longus insert?
Base of the distal phalanx of the thumb
Which nerve innervates the flexor pollicis longus?
Median nerve
What is the action of the flexor pollicis longus?
Flexes distal phalanx of the thumb
Where does the pronator quadratus originate from?
Distal fourth of the anterior surface of the ulna
Where does the pronator quadratus insert?
Distal fourth of the anterior surface of the radius
Which nerve innervates the pronator quadratus?
Median nerve
What is the action of the pronator quadratus?
Pronates hand
Which nerve innervates the hypothenar eminence?
Ulnar nerve
Which muscles comprise the hypothenar eminence?
Opponens digit minimi
Abductor Digiti minimi
Flexor digiti minimi brevis
Which hypothenar muscle lies deep?
Opponens digiti minimi
What is the action of the opponens digiti minimi?
Rotates the metacarpal of the little finger towards the palm , producing opposition
Where does the opponens digiti minimi originate from?
From the hook of hamate and associated flexor retinaculumz
Where does the opponens digiti minimi insert into?
Medial margin of metacarpal V
Which hypothenar muscle is superficial?
Abductor Digit minimi
What is the action of the abductor digiti minimi?
Abducts the little finger
What is the origin of the abductor digiti minimi?
Pisiform and tendon of the flexor carpi ulnaris
Where does the abductor digiti minimi insert?
Base of the proximal phalanx of the little finger
Which muscle resides literally to the abductor digit mimi?
Flexor digiti minimi brevis
Where does the flexor digiti minimi brevis originate from?
Hook of hamate and adjacent flexor retinaculum
Where does the flexor digiti minimi brevis insert?
Inserting into the base of the proximal phalanx of the little finger
What is the action of the flexor digiti minimi brevis?
Flexes the MCP joint of the little finger
Which three muscles comprise the thenar eminence?
Opponens pollicis
Abducotr pollicis brevis
Flexor pollicis brevis
Which nerve innervates the thenar muscles?
Median nerve
Which thenar muscle is the largest?
Opponens Pollicis:
Which thenar muscle resides deep?
Opponens Pollicis:
What is the action of the Opponens Pollicis?
Opposes the thumb, by medially rotating and flexing the metacarpal of the trapezium
Where does the Opponens Pollicis originate from?
From the tubercle of the trapezium, and associated flexor retinaculum
Where does the Opponens Pollicis insert?
Lateral margin of the first metacarpal
Which thenar muscle resides anteriorly to the opponens pollicis?
Abductor Pollicis Brevis:
Where does the Abductor Pollicis Brevis originates from?
Originates from the tubercle of the scaphoid and trapezium and the associated flexor retinaculum
Where does the Abductor Pollicis Brevis insert?
Lateral side of the proximal phalanx of the thumb
What is the action of the Abductor Pollicis Brevis?
Abducts the thumb
Which muscle is the. most distal?
Flexor Pollicis Brevis:
Where does the Flexor Pollicis Brevis originate?
Originates from the tubercle of the trapezium and from the associated flexor retinaculum
Where does the Flexor Pollicis Brevis insert?
Base of the proximal phalanx of the thumb
What is the action of the Flexor Pollicis Brevis?
Flexes the MCP joint of the thumb
What is the total number of lumbricals?
4
Denervation of the lumbricals leads to which two pathologies?
Ulnar claw
Hand of benediction
Where do the lumbricals attach too?
Traverses dorsally and laterally around each phalanx , inserting into each extensor hood
Where do the lumbricals attach originate?
Originates from a tendon of the flexor digitorum profundus
Which nerve innervates the lateral two lumbricals?
Median nerve
Which nerve innervates the medial two lumbricals?
Ulnar nerve
What interossei abduct the fingers?
Dorsal interossei
Which interossei adducts?
Palmar interossei
Which nerve innervates the interossei muscles?
Ulnar nerve
What are the functions of the interossei muscles?
In addition to their actions of abduction (Dorsal interossei) and adduction (Palmar interossei) of the fingers, the interossei further assist the lumbricals in flexion at the MCP joints, and extension at the IP joints.
Where do the dorsal interossei muscle originate from?
Each interossei originates from the lateral and medial surfaces of the metacarpals
Where do the dorsal interossei muscles insert?
Attach into the extensor hood and proximal phalanx of each finger
What is the main action of the dorsal interossei muscles?
Abduct the fingers at the MCP joint.
What is the main action of the palmar interossei muscles?
Adducts the fingers at the MCP joint.
What forms the medial base of the carpal arch?
Medially by the pisiform and the hook of hamate
What is the carpal tunnel?
The carpal tunnel resides on the anterior portion of the wrist, providing the entrance to the palm for multiple tendons (9), and the median nerve. (Surrounds the synovial sheaths)
Which nerve passes through the carpal tunnel?
Median nerve
What is the flexor retinaculum?
Thick connective tissue which forms the roof of the carpal tunnels -> Converts the carpal arch into the carpal tunnel by bridging the space between the medial and lateral regions of the arch
What is the function of the flexor retinaculum?
Holds the tendons to the bony plane at the first; preventing bowing.
Free movement of tendons is facilitated by the associated synovial sheaths encapsulating the tendons
Which tendon is separated by a single synovial sheath?
Flexor pollicis longus
Which 8 tendons are surrounded by the same synovial sheath?
Flexor digitorum profundus
Flexor digitorum superficialis
Which artery passes into the hand anterior to the flexor retinaculum?
Ulnar artery
What is carpal tunnel syndrome?
Carpal tunnel syndrome: Entrapment syndrome caused by pressure on the median nerve
What is the palmar aponeurosis?
The palmar aponeurosis is a triangular condensation of deep fascia that covers the palm, anchored to the skin in the distal regions. The apex of the triangle is continuous with the palmaris longus tendon Fibres radiate to extensions at the bases of the digits that project into each of the index, middle, ring and little fingers.
Vessels, nerves, and long flexor tendons reside deep to the palmar aponeurosis in the palm.
What is the palmaris brevis?
Small intrinsic muscle of the hand, quadrangular shaped subcutaneous muscle overlying the hypothenar muscles, ulnar artery and superficial branch of the ulnar nerves at the medial side of the palm
What forms the lateral border of the anatomical snuffbox?
Tendons of the abductor pollicis longus and extensor polices brevis
What forms the medial border of the anatomical snuffbox?
Tendon of the extensor pollicis longus
What forms the floor of the anatomical snuffbox?
Impression if formed by the scaphoid and trapezium. Distal ends of the tendons of the extensor carpi radialis longus, and extensor carpi radialis brevis.
What is the anatomical snuffbox?
The anatomical snuff box is a term given to the triangular depression formed on the posterolateral side of the wrist, and metacarpal I, by the extensor tendons passing into the thumb.
The base of the wrist and the apex is directed into the thumb. The impression is more apparent when the thumb is extended.
What forms the posterior compartment of muscles?
Extensor muscles Brachioradialis Extensor carpi radialis longus Extensor carpi radialis brevis Extensor digitorum digit minimi Extensor carpi ulnaris Aceonaeus
What is the common attachment for the extensor compartment?
Lateral epicondyle of the humerus
What are the deep extensor muscles?
Supinator, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, extensor indicis.
What is the action of the extensor carpi radalis?
Extension and abduction of the wrist
Which nerve innervates the majority of extensor muscles?
Radial nerve
What is the action of the extensor carpi ulnaris?
Extension and adduction of the wrist
