Musculoskeletal System Flashcards
What is another name for fossa?
Cavity
What is another name for sulcus?
Groove
When is a depression called a sulcus/groove and not a fossa?
When a blood vessel/tendon/structure is running through it.
What is a notch?
U shaped structure
What are the true joints in the shoulder?
Sternoclavicular joint Acromioclavicular joint Glenohumeral joint (shoulder joint)
Where does the deltoid attach on the humerous?
Deltoid tuberosity
What is the function of rotator cuff muscles?
They stabilise glenohumeral joint (shoulder joint)
What are the rotator cuff muscles?
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
Where does the brachial artery end?
Elbow joint
Where does the axillary artery end?
Below teres major
What is the shoulder girdle?
Scapula
Clavicle
What is the name of the concave depression on the costal side of the scapula?
Subscapular fossa
To which part of the scapula does the short head of biceps brachii attach?
Coracoid process
Which fossa of the scapula articulates with the humerus?
Glenoid fossa
What part of the scapula articulates with the clavicle?
Acromion
Injury to which nerve causes winging of the scapula and which muscle does this innervate?
Long thoracic nerve which innervates the serratus anterior muscle
What are the functions of the clavicle?
Attaches upper limb to trunk
Protects underlying neurovascular structures
Transmits force from the upper limb to the axial skeleton
What attaches to the clavicle at the considered tubercle?
Conoid ligament (medial part of the coracoclavicular ligament)
What is the most common point of fracture of the clavicle?
Between medial 2/3 and lateral 1/3 as this is the weakest point- structure of clavicle changes
Which nerve can be damaged in a clavicular fracture?
Suprascapular nerves- damaged by upwards movement of medial fragment
What is a tubercle?
A round nodule on a bone and signifies an attachment site of a muscle or ligament
What is a facet?
Small smooth area on a bone covered with articular cartilage
Which of the rotator cuff muscles does not attach to the greater tubercle of the humerus?
Subscapularis- attaches to the lesser tubercle of the humerus anteriorly
Which nerve can be damaged in a surgical neck fracture of the humerus?
Axillary nerve- very close to the surgical neck
What deformity occurs if there is damage to the radial nerve?
Wrist drop
radial nerve innervates the extensors of the wrist so damage results in unopposed flexion of the wrist
Which bone does the trochlea of the humerus articulate with?
Ulna
Which fossae are located on the distal humerus?
Radial fossa- anterior humerus
Coronoid fossa- anterior humerus
Olecranon fossa- posterior humerus
Which fracture of the humerus can lead to Volkmanns contracture?
Supraepicondylar fracture- transverse fracture spanning between the two epicondyles
Results in interference to the blood supply of the forearm from the brachial artery.
Ischaemia results in uncontrolled flexion of the hand because muscles become fibrotic and short.
What area on the ulna articulates with the head of the radius?
Radial notch
Which muscle attaches to the tuberosity of the ulna?
Brachialis
Which muscle attaches to the anterior shaft of the ulna?
Pronator quadratus
Where is the most likely point of fracture on the ulna?
Shaft
Which bones does the radius articulate with?
Ulna
Humerus
Scaphoid
Lunate
Which muscle attaches to the lateral surface of the radius?
Pronator teres
Which landmark on the radius articulates with the distal ulna?
Ulnar notch
In a Colles fracture, in which direction is the distal radius displaced?
Posterior
What is a sesamoid bone?
A small independent bone or bony nodule developed in a tendon where it passes over an angular structure
Where will pain be felt in a scaphoid fracture?
Anatomical snuffbox
Which nerve can be damaged in a fracture of the lunate?
Median nerve
Which metacarpal is fractured in a Boxers fracture?
Fifth - fracture of this bone often occurs as a result of a clenched fist striking a hard surface in a hammer punch
Which digit only contains two phalanges, as opposed to three?
Thumb
What is the innervation of pectoralis major?
Medial and lateral pectoral nerves
What action does the clavicular head of pectoralis major perform on the shoulder?
Flexion
Also helped by some anterior fibres of the deltoid muscle
Where is pectoralis minor located in comparison to pectoralis major?
Posterior
Where on the scapula does pectoralis minor attach?
Corocoid process
Which wall of the axilla does serratus anterior form?
Medial- serratus anterior is found on the outer aspect of the rib cage
What is the main action of serratus anterior?
Rotating the scapula- allows the arm to be raised over 90 degrees
Injury to which nerve can cause winging of the scapula?
Long thoracic nerve- supplies serratus anterior which holds the scapula against the rib cage
What is the quadrangular space?
Gap that the axillary nerve and posterior circumflex humeral artery pass through to reach the posterior scapula region
Which nerve innervates the deltoid muscles?
Axillary nerve
What is the action of the anterior fibres of the deltoid?
Flexes the shoulder
Which nerve innervates teres major?
Lower subscapular nerve
What are the actions of teres major?
Medial rotation of the arm
Adduction of shoulder
Which nerve innervates supraspinatus?
Suprascapular nerve
What is the action of infraspinatus?
Lateral rotation of the arm
Which nerve innervates teres minor?
Axillary nerve
Which muscle is typically affected in rotator cuff tendinitis?
Supraspinatus
What forms the medial wall of the axilla?
Serratus anterior and thoracic wall
The subscapularis muscle forms which border of the axilla?
Posterior wall
What structure enters the axilla through the clavipectoral triangle?
Cephalic vein
Which muscles travel through the axilla?
Short head of biceps brachii
Coracobrachialis
What can be biopsied in suspected breast cancer?
Axillary lymph nodes as these are the nodes to which 75% of lymph fluid from the breast drains first.
Which nerve innervates the trapezius muscle?
Accessory nerve
What is the action of the middle fibres of the trapezius?
Retract the scapula
Which nerve innervates latissimus dorsi?
Thoracodorsal nerve
What is the action of levator scapulae?
Elevates the scapula
Which nerve innervates the rhomboids?
Dorsal scapular nerve
What is the action of the rhomboid?
Retract and rotate the scapula
Which nerve innervates the anterior compartment of the upper arm?
Musculocutaneous nerve
Where does the long head of the biceps brachial originate?
Supraglenoid tubercle
What is the main function of biceps brachii?
Supination of the forearm
What is the action of coracobrachialis?
Flex and adduct arm
What is the action of triceps brachii?
Extension of the elbow
Where do the superficial muscles of the anterior forearm originate?
Medial epicondyle of the humerus
Which nerve innervates flexor carpi ulnaris?
Ulnar nerve
All muscles in anterior forearm are innervated by median nerve except:
Flexor carpi ulnaris
Medial half of flexor digitorum profundus (innervates ring finger and little finger)
Which nerve innervates flexor carpi radialis?
Median nerve
What is the action of pronator teres?
Pronation of the forearm
Which of the following joints does flexor digitorum superficialis not act on?
- wrist
- metacarpophalangeal joints
- distal interphalangeal joints
- proximal interphalangeal joints
Distal interphalangeal joints - only acted on by flexor digitorum profundus
Which nerve innervates the lateral half of flexor digitorum profundus and which fingers does this innervate?
Median nerve- middle finger and index finger
Where does flexor pollicis longus lie in relation to flexor digitorum profundus?
Lateral
What is the action of pronator quadratus?
Pronation of the forearm
What is the action of the brachioradialis?
Flexion of the elbow
What nerve innervates all the muscles in the posterior forearm?
Radial nerve
What is the main action of extensor digiti minimi?
Extension of the little finger
What is the action of anconeus?
Abducts the ulna in pronation
Extends at elbow joint
What is the common site of origin for posterior forearm muscles?
Lateral epicondyle
Which muscle tendons contribute to the borders of the anatomical snuffbox?
Abductor pollicis longus = lateral border
Extensor pollicis brevis = lateral border
Extensor pollicis longus = medial border
Which border of the anatomical snuffbox does the tendon of extensor pollicis longus form?
Medial
Which joint does extensor pollicis brevity act on?
Metacarpophalangeal joints of the thumb
Carpometacarpal joints of the thumb
Injury to which nerve results in wrist drop?
Radial nerve
Where are the common sites of injury that result in wrist drop and how?
Axilla - injured via humeral dislocations or fractures of proximal humerus
Radial groove of humerus- injured via humeral shaft fracture
DAMAGES RADIAL NERVE
What is the action of opponens pollicis?
Opposition of the thumb
Which nerve innervates flexor pollicis brevis?
Median nerve innervates the thenar eminence
Which nerve innervates opponents digiti minimi?
Ulnar nerve innervates the hypothenar eminence
What is the action of abductor digiti minimise?
Abduction of the little finger
Which nerve innervates the medial two lumbricals?
Ulnar nerve
What action does the lumbricals have on the metacarpophalangeal joints?
Flexion
What is the action of the dorsal interossei?
Abduction of the fingers
What is the action of palmaris brevis?
Deeps the curvature of the hand to improve grip
What are the extrinsic muscles of the hand?
Muscles in the anterior and posterior compartments of the forearm that control crude movements and produce a forceful grip
What are the ligaments of the shoulder joint? (4)
Glenohumeral ligaments x3
Transverse humeral ligament
Coracohumeral ligament
Coracoacromial ligament
Which artery supplies the shoulder joint?
Suprascapular artery
Which nerves supply innervation to the shoulder joint?
Axillary nerves
Suprascapular nerve
Lateral pectoral nerve
What contributes to the stability of the shoulder joint?
Ligaments
Glenoid labrum
Rotator cuff muscles
What is the most common direction of dislocation of the shoulder joint?
Anterior
What are the articulating surfaces of the elbow joint?
Trochlear notch of the ulna and the trochlear of the humerus
Head of the radius and the capitulum of the humerus
Which muscles contribute to flexion of the elbow joint?
Brachialis
Biceps brachii
Brachioradialis
What are the clinically important bursae of the elbow joint?
Intratendinous - located within the tendon of the triceps brachii
Subtendinous - between the olecranon and the tendon of the triceps brachii, reducing friction between the two structures during flexion and extension of the arm
Subcutaneous- between the olecranon and overlying connective tissue
What area becomes inflamed in tennis elbow?
Lateral epicondyle- main site of attachment of extensor tendons
Caused by overuse strain on tendons
What nerves are at risk of damage in a supraepicondyle fracture?
Medial, ulnar or radial nerves
Which bones form the articulatory surfaces of the wrist joint?
Distal end of the radius and articular disk
Proximal row of the carpal bones- scaphoid, lunate, triquetrum (except pisiform)
Which type of joint is the wrist?
Ellipsoid synovial joint = allows movement along two axis ie. flexion/extension AND abduction/adduction
Which bone in the hand when fractured is most likely to result in avascular necrosis and why?
Scaphoid- the bone has distal to proximal blood supply and this may be disrupted
Which nerves provide innervation to the wrist joint?
Median nerve
Radial nerve
Ulnar nerve
Which artery accompanies the axillary nerve when exiting the axilla in the quadrangular space?
Posterior humeral circumflex artery
What forms the inferior border of the quadrangular space?
Teres major
Which muscles does the axillary nerve innervate?
Deltoid
Teres minor
What area does the axillary nerve provide sensory innervation to?
Regimental badge area
Which muscle rapidly atrophies following damage to the axillary nerve?
Deltoid
Which nerve roots contribute to the musculocutaneous nerve?
C5 C6 C7
Which cord of the brachial plexus gives rise to the musculocutaneous nerve?
Lateral
What is the name of the sensory branch of the musculocutaneous nerve?
Lateral cutaneous branch- provides sensory innervation to the skin of the lateral forearm
Which muscles does the muscle does the musculocutaneous nerve innervate?
Biceps brachii
Brachialis
Coracobrachialis
Which area does the musculocutaneous nerve provide sensory innervation to?
Lateral forearm
The median nerve innervates all muscles in the anterior forearm except…
Flexor carpi ulnaris - ulnar nerve
Medial half of flexor digitorum profundus - ulnar nerve
The ulnar nerve provides motor innervation to all muscles in the hand except…
Thenar muscles - median nerve
Lateral two lumbricals (middle and index finger) - median nerve
Which nerve roots contribute to the median nerve?
C6 C7 C8 T1
Which artery does the median nerve cross in the arm?
Brachial artery
Which group of muscles atrophied in carpal tunnel syndrome?
Thenar eminence
Which deformity occurs when the median nerve is damaged at the elbow?
Hand of Benediction
Which landmark of the humerus marks the course of the radial nerve?
Radial groove- small depression on the posterior aspect of the humerus
Which group of muscles does the radial nerve innervate?
Posterior arm
How many cutaneous branches does the radial nerve give off?
Four
What deformity occurs if there is damage to the radial nerve in the axilla?
Wrist drop
Which muscles are affected if the superficial branch of the radial nerve is damaged?
None- this is a sensory nerve
At what bony landmark of the humerus is the ulnar nerve vulnerable to damage?
Medial epicondyle
Which muscle does the ulnar nerve pierce in the forearm?
Flexor carpi ulnaris-passes between the two heads
Which fingers does the ulnar nerve provide cutaneous innervation to?
Medial one and a half fingers
What deformity occurs if the ulnar nerve is injured at the wrist?
Ulnar claw
Which vessel does the left subclavian artery arise from?
Arch of the aorta
What muscle does the axillary artery pass beneath?
Pectoralis minor
What is the name of the deep artery of the arm?
Profunda brachii
What clinical sign indicates ischaemia of the forearm?
Volkmann’s contracture- scar tissue results in muscle shortening
Which arteries directly supplies blood to the hand?
Superficial and deep palmar arches
What is the superficial palmar arch found deep to?
Palmar aponeurosis
At what point does the basilica vein move deep in the arm?
Border of teres major
Which vein does the cephalic vein drain into?
Axillary vein
What are the deep veins of the arm situated beneath?
Deep fascia
What name is given to the arrangement of accompanying veins around an artery?
Vena comitantes
What are the superficial veins in the upper limb
Basilic vein
Cephalic vein
Both drain into axillary vein
What forms the medial border of the cubital fossa?
Lateral border of pronator teres
What forms the floor of the cubical fossa?
Brachialis and supinator
Name the structures in the cubical fossa, lateral to medial.
Radial nerve
Biceps tendon
Brachial artery
Median nerve
Where can you feel the for the brachial pulse?
Medial to the biceps tendon
What vein is commonly used for venepuncture?
Median cubical vein - superficial and easily accessible
What forms the medial border of the anatomical snuffbox?
Tendon of extensor pollicis longus
What bones form part of the floor of the anatomical snuffbox?
Scaphoid and trapezium
Which artery passes through the anatomical snuffbox?
Radial artery
Which vein passes through the anatomical snuffbox?
Cephalic vein
What causes tenderness in the anatomical snuffbox?
Scaphoid fracture- vulnerable to avascular necrosis as blood flow is lateral to medial
On which side of the leg is the fibula found?
Lateral aspect
Which key nerve of the leg wraps around the neck of the fibula?
Common fibula- after wrapping around the neck of the fibula, the common fibula nerve gives rise to the superficial and deep fibula nerves
Which movement of the ankle can lead to a spiral fracture of the fibula?
Lateral rotation - the force of the talus against the lateral malleolus of the fibula causes a spiral fracture
What is the name of the flat surface at the superior end of the tibia, formed by the condyles?
Tibial plateau
Which structure articulates with the intercondylar fossa of the femur?
Intercondylar eminence of the tibia - combination of intercondylar tubercles and area of roughened bone between them
Which structure of the anterior tibia is damaged to cause bruising?
Tibial tuberosity- marks the anterior surface of the tibia where the periosteal covering is particularly open to damage
Which two bony structures are implicated in a spiral fracture of the tibia and how?
Medial malleolus and talus- over inversion of the ankle joint, the talus is forced into the medial malleolus causing a spiral fracture
What type of bone is the patella?
Sesamoid
What attaches to the base of the patella?
Quadriceps tendon - provides attachment of the quadriceps (3 vastus muscles and rectus femoris)
What attaches to the apex of the patella?
Patellar ligament- connects the patella to the tibial tuberosity
In what direction is the patella most likely to dislocate?
Laterally- the medial collateral ligament is weaker than the lateral collateral ligament making it more susceptible to injury and lateral patellar dislocation more likely
To which part of the femur do the lateral rotators of the lower limb attach to?
Greater trochanter- this is the lateral aspect of the hip joint so the lateral rotators attach here
Which strong ligament attaches to the intertrochanteric line?
Iliofemoral ligament
On which part of the femur can you find the intertrochanteric crest?
Posterior aspect
What happens to the position of the lower limb after neck of femur fracture?
Laterally rotated and superiorly displaced (shortened)
What is the name of the structure to which adductor magnus attaches?
Adductor tubercle
Which two structures at the distal end of the femur articulate with the tibia to create the knee joint?
Condyles
How many bones make up the tarsals?
Seven:
Calcaneus, navicular, talus, cuboid, three cuneiforms
Which bones articulate with the talus?
Tibia and Fibula (ankle joint)
Calcaneus
Navicular
To which bone of the foot does tibialis posterior inset into?
Tibialis posterior inserts into the navicular after passing through the tarsal tunnel to produce inversion
Which is the most lateral bone in the distal row of the tarsals?
Cuboid
Why do fractures of the talus have minimal displacement?
The talus is found firmly supported within the malleoli and this prevents them from displacing
A strain of which muscle can lead to an allusion fracture of the 5th metatarsal?
Fibularis brevis- attaches to 5th metatarsal and can cause avulsion fractures especially in forced inversion
What is the insertion of the gluteus maximum?
Gluteus tuberosity- lateral ridge of the linea aspera
Which nerve innervates the gluteus maximum?
Inferior gluteal
Damage to which nerve causes a pelvic drop?
Superior gluteal
Loss of gluteus medium and minimus activation
These muscles contract when the contralateral leg is raised, preventing the pelvis from dropping on that side
Which muscle lies between the gemilli?
Obturator internis
Which muscle of the quadriceps crosses both the hip and knee joint?
Rectus femoris - flexes hip joint, extends knee joint
What is the innervation of psoas major?
Anterior rami L1-L3
Describe the function of sartorius at the hip.
Flexion, abduction, lateral rotation
Damage to which nerve root would affect the function of the femoral nerve?
L3
From which nerve plexus does the obturator nerve arise?
Lumbar plexus
Which two nerves innervate adductor magnus?
Tibial nerve supplies hamstring part
Obturator nerve supplies adductor part
Which muscle is the most superior muscle of the medial thigh?
Obturator externus
What are the hamstrings?
Muscles in the posterior compartment of the thigh:
Biceps femoris
Semitendinous
Semimembranosus
They extend at the hip and flex at the knee
What innervates the short head of biceps femoris?
Common fibular part of sciatic nerve
Which is the most medial muscle of the hamstrings?
Semimembranosus
What is the correct function of all the hamstrings at the knee?
Flexion- they attach to the posterior aspect and reduce the angle found at the joint
Which muscle of the hamstrings causes lateral rotation at the hip and knee?
Biceps femoris - located on the lateral aspect of the knee joint
Which of the four muscles in the anterior compartment of the leg cause eversion at the ankle?
Fibularis tertius
What are the nerve roots of the deep fibula nerve?
L4-L5
Which muscle attaches to the base of the first metatarsal?
Tibialis anterior
What causes a foot drop?
Damage to the common fibula nerve causing loss of dorsiflexion
Which is the most superficial of the muscles of the anterior leg?
Tibialis anterior
In which direction does the sole of the foot turn to face during eversion?
Laterally
Which nerve innervates both muscles of the lateral leg?
Superficial fibular nerve
What is a function of fibularis longus that is not shared by fibularis brevity?
Plantarflexion
Which nerve roots does the calcaneal reflex assess?
S1-S2
Which muscle flexes at the knee and plantarflex at the ankle?
Gastrocnemius
Which movement places the calcaneal tendon most at risk?
Forceful jumping
In which direction does the femur move to unlock the knee?
Rotates laterally
What is the function of tibialis posterior?
Plantar flexion and inversion
Which muscle passes closest to the medial malleolus from the deep muscles of the leg?
Tibialis posterior
How can you tell whether you are looking at the left or right humerus?
Medial epicondyle is larger and projects further than the lateral epicondyle
Which is the biggest carpal bone?
Capitate
How does the axillary artery exit the axilla?
What structure also goes through here?
Quadrangular space
Posterior humeral circumflex artery
What are the boundaries of the quadrangular space?
Superior
Subscapularis and teres minor
Inferior
Teres major
Lateral
Surgical neck of humerus
Medial
Long head of triceps brachii
What goes through the quadrangular space?
Axillary artery
Posterior humeral circumflex artery
Describe the anatomical course of the axillary nerve.
-formed within the axilla region from the posterior cord of the brachial plexus, posterior to the clavicle
-lies posteriorly to the axillary artery and anteriorly to the subscapularis muscle
-descends to the inferior border of the subscapularis muscle
-exits the axilla via the quadrangular space, with the posterior humeral circumflex artery
-terminates by dividing into 2 branches:
Posterior terminal branch - motor innervation teres minor and sensory innervation to skin over the inferior part of the deltoid (regimental badge area)
Anterior terminal branch - motor innervation to deltoid
What would injury to the axillary nerve present as?
Motor functions: paralysis of deltoid and teres minor muscles. Loss of abduction
Sensory functions: posterior terminal branch gives cutaneous innervation to the skin over the lower deltoid (regimental badge area)
Characteristic clinical signs:
Paralysed deltoid muscle rapidly atrophies, greater tuberosity can be palpated
Describe the anatomical course of the radial nerve.
Arises in axilla region from the posterior cord
Exits via the triangular interval to the posterior arm with profunda brachii
Descends down the humerus in the radial groove with profound a brachii
Moves anteriorly over the lateral epicondyle through the cubical fossa to enter the forearm
Branches into 2:
-deep branch (motor) - innervates most of the muscles in the posterior compartment of the forearm
-superficial branch (sensory) - contributes to the cutaneous innervation of the hand and fingers
What does the profunda brachii supply?
Supplies the posterior compartment of the upper arm
The trapezius attaches to the acromion, spine of the scapula and lateral clavicle.
Another muscle originates in the same places, which muscle?
Deltoid
All muscles in the anterior forearm are innervated by the median nerve except…
Extensor carpi ulnaris
Medial half of flexor digitorum profundus
Are innervated by the ulnar nerve
All muscles in the hand are innervated by the ulnar nerve except…
Thenar muscles
Lateral two lumbricals
Are innervated by the median nerve
Describe the anatomical course of the median nerve.
Derived from the medial and lateral cords of the brachial plexus in the axilla
Descends down the arm, initially lateral to the brachial artery
Halfway down the arm, the nerve crosses over the brachial artery and is edible to it
Enters the anterior compartment of the forearm via the cubical fossa
Travels between flexor digitorum profundus and flexor digitorum superficialis
Enters hand via the carpal tunnel and terminates by dividing into:
-recurrent branch - supplies thenar muscles
-palmar digital branch - supplies fingertips of lateral 3 and a half digits and lateral 2 lumbricals
Sensory innervation of dorsal lateral 3 and a half digits and associated palm area is by…
Radial nerve
Sensory innervation to the fingertips of the lateral 3 and a half digits is by…
Median nerve
What is the sensory function of the median nerve in the hand?
Palmar cutaneous branch - palm area of lateral 3 and a half digits
Palmar digital cutaneous branch - anterior lateral 3 digits and fingertips
Describe the anatomical course of the ulnar nerve.
Derived from the medial cord of the brachial plexus in the axilla
Descends down the medial side of the upper arm
At the elbow, passes posterior to the medial epicondyle entering the forearm
In the forearm, pierces the two heads of flexor carpi ulnaris and travels alongside the ulnar
Three branches arise:
-muscular branch - medial half of flexor digitorum profundus
-palmar cutaneous branch - medial palm
-dorsal cutaneous branch - anterior and dorsal 1 and a half digits and associated dorsal palm area
Describe the anatomical course of the musculocutaneous nerve.
Arises from the lateral cord of the brachial plexus
Leaves the axilla and pierces the coracobrachialis muscle near its point of insertion on the humerus (level of deltoid tuberosity)
Passes down the arm, anterior to the brachialis muscle but deep to biceps brachii
Emerges laterally to the biceps tendon and continues into the forearm as the lateral cutaneous nerve.