MSK

Question 1

Which muscles are responsible for abduction of the shoulder

Answer 1

Initiation is supraspinatus and then it is assisted by deltoid. Rotation of the scapula is by trapezius

Question 2

Describe the movements of the scapula and humerus during abduction of the shoulder.

Answer 2

Supraspinatus initiates abduction and after 10-15 degrees it is assisted by deltoid. As the arm rises the humerus externally rotates to keep the articular surfaces in contact. At full abduction (upper limb vertically above the head) the humerus has externally rotated 90 degrees. For every 2 degrees of abduction at the glenohumeral joint the scapula rotates by 1 degree over the thoracic wall. In full abduction (upper limb vertically above the head) the scapula is rotated so that the glenoid points upwards by 60 degrees.

Question 3

Which nerve supplies trapezius?

Answer 3

Spinal accessory nerve (cranial nerve XI)

Question 4

Which nerve is damaged by a posterior dislocation of the shoulder and what sensory and motor loss is experienced?

Answer 4

Axillary nerve; sensory loss in skin over the insertion of deltoid muscle and paralysis of deltoid.

Question 5

What structures stabilise the shoulder joint?

Answer 5

The rotator cuff muscles; supraspinatus, infraspinatus, teres minor and subscapularis.

Question 6

Which bony parts of the shoulder girdle lie subcutaneously and can be palpated easily?

Answer 6

Manubrium sternum, clavicle, spine of the scapula and acromium.

Question 7

Will “Saturday night palsy” result in a weakness of triceps, explain your answer?

Answer 7

No. Saturday night palsy is loss of function of the radial nerve as it runs against the mid-shaft of the humerus in the spiral groove. Although the posterior compartment of the arm, which is formed by triceps, is supplied by the radial nerve the branches leave the nerve before the spiral groove.

Question 8

How does blood reach the right axillary artery from the left ventricle? (Name the arteries through which it passes.)

Answer 8

Aorta, brachiocephalic artery, subclavian artery, axillary artery.

Question 9

Draw and label a diagram of the brachial plexus showing its parts and major branches.

Answer 9

(see diagram)

Question 10

Outline the arrangement of the cords of the brachial plexus around the second part of the axillary artery

Answer 10

The cords of the brachial plexus lie lateral, medial and posterior to the axillary artery (immediately behind pectoralis minor muscle).

Question 11

Which muscles for the rotator cuff, where are they inserted?

Answer 11

Supraspinatus; superior facet on the greater tuberosity of the humerus,

Infraspinatus; middle facet on the greater tuberosity of the humerus,

Teres minor; inferior facet on the greater tuberosity of the humerus,

Subscapularis; Lesser tuberosity of the humerus.

Question 12

Briefly describe the various lymph node groups in the axilla and their clinical significance.

Answer 12

a) anterior; directly under pectoralis major
b) lateral; between pectoralis major and latissimus dorsi close to the humerus
c) posterior; lying against teres major at the back of the axilla
d) central; inferior to the neurovascular bundle deep to pectoralis minor
e) apical; adjacent to the outer border of the first rib

Question 13

What parts of the body drain lymph directly to the axillary lymph nodes?

Answer 13

Ipsilateral upper limb and body wall above the umbilicus.

Question 14

What structures lie along the medial border of the biceps in the middle of the arm?

Answer 14

Median nerve , ulna nerve, medial cutaneous nerve of the forearm, brachial artery and basilar vein.

Question 15

What are the 3 superficial veins of the forearm and where do then run?

Answer 15

The cephalic vein arises from the lateral end of the dorsal venous arch on the back of the hand. It runs more or less over the radius up to the antecubital fossa where is gives the antecubital vein. It continues in the groove between triceps and biceps on the lateral side of the arm until it reaches deltoid where it passes up in the delto-pectoral grove to just below the clavicle. Just below the clavicle it passes deep into the axillary vein.
The basilic vein arises from the medial end of the dorsal venous arch on the back of the hand. It passes up the forearm more or less over the ulna to pass medial to the elbow joint where it is joined by the antecubital vein. It passes half way up the medial side of the arm in the groove between triceps and biceps. Half way up the arm it passes deep to become the brachial vein.

Question 16

What are the three major nerves entering the forearm and what do they supply?

Answer 16

Radial; motor to the posterior compartment and skin on the lateral part of the back of the hand (first web space),
Median nerve; Motor to all muscles in flexor forearm EXCEPT flexor carpi ulnaris and ulna half of flexor digitorum profundus (both ulna nerve). Motor to the LLOAF muscles of the hand; lateral lumbricles, opponense pollicis, abductor pollicis brevis, flexor pollicis brevis. Skin on lateral 3.5 digits on palm of hand.
Ulna nerve; Motor flexor carpi ulnaris and ulna half of flexor digitorum profundus. Motor all muscles in hand EXCEP LLOAF. Skin medial 1.5 digits on palm of hand.

Question 17

Where is the common flexor origin?

Answer 17

Medial epicondyle of the humerus.

Question 18

How do you test the muscles supplied by the median nerve?

Answer 18

Flexion of the thumb and lateral two fingers. Movement of the thenar muscles

Question 19

Where can you palpate the brachial, radial and ulna arteries? Which is easier to palpate? Why

Answer 19

Brachial, medial to the biceps aponeurosis.
Ulna, lateral to the pisiform or just proximal to this position.
Radial Lateral to the most lateral tendon at the wrist; this is the easiest because it is superficial and has bone directly behind it.

Question 20

Where does the brachial artery and median nerve pass into the forearm?

Answer 20

Medial to the biceps aponeurosis.

Question 21

What is pronation and supination; which muscles perform these movements?

Answer 21

forwards in the anatomical position or upwards with the elbow flexed. Supinator (in any position of the elbow) and biceps (with the elbow flexed) produce supination.
Pronation is positioning the radius and ulna crossing each other; the hand faces backwards in the anatomical position or downwards with the elbow flexed. Pronator teres and pronator quadratus (in any position of the elbow) produces pronation.

Question 22

Which carpal bone is most prone to injury?

Answer 22

Scaphoid; it is in direct contact with the radius so putting your hand out to stop yourself falling over will put all the force directly through the scaphoid.

Question 23

What is the cutaneous distribution of the median and ulnar nerves in the hand?

Answer 23

Median; palmer lateral 3.5 digits and extending over the finger tips up to the nail bed.
Ulna; palmer medial 1.5 digits and extending over the finger tips up to the nail bed.

Question 24

What are the thenar muscles? What is their nerve supply?

Answer 24

The thenar muscles are at the base of the thumb on the palmar side of the hand (opponens pollicis, abductor pollicis brevis, flexor pollicis brevis). They are supplied by the median nerve.

Question 25

If infection occurs in the synovial flexor tendon sheath how far will it spread in the:

a) middle finger? 
b) thumb? 
c) little finger?

Answer 25

a) To the distal skin crease on the palm of the hand
b) Into the forearm
c) Into the forearm

Question 26

How do you test the interossei muscles?

Answer 26

Test abduction and adduction of the fingers.

Question 27

What are the differences in the motor and sensory loss due to these two injuries?

Answer 27

question incomplete - ignore

Question 28

How does division of the median nerve at the elbow differ from one at the wrist?

Answer 28

Sensory loss will be the same. Motor at the wrist will paralyse the LLOAF muscles (lateral lumbricles, opponens pollicis, abductor pollicis brevis, flexor pollicis brevis). Motor at the elbow will paralyse the long flexor to the thumb, both flexors to the index and middle fingers and the superficial flexors to the ring and little finger (and LLOAF).

Question 29

What is the nerve supply of the extensor compartment of the forearm and what area of skin does this nerve also supply?

Answer 29

Radial nerve; skin on the dorsal aspect of the lateral 3.5 digits up to the distal interphalangeal joint.

Question 30

Which bone lies in the base of the anatomical snuff box?

Answer 30

Scaphoid

Question 31

Which nerve and vein cross the anatomical snuff box superficially?

Answer 31

Radial nerve, cephalic vein.

Question 32

If the Thoracic 1 nerve root is damaged which group of muscles will be paralysed and which area of skin will be anaesthetic?

Answer 32

All the muscles in the hand are paralysed and the skin over the medial arm is anaesthetic.

Question 33

Which muscle is the most powerful supinator and which position does the elbow need to be in to maximise its force?

Answer 33

Biceps, with the elbow flexed to 90 degrees.

Question 34

Which fingers have two extensor muscles and tendons?

Answer 34

Index and little fingers.

Question 35

Describe how the radius moves during pronation and supination.

Answer 35

The proximal radius rotates about its own axis, the distal radius rotates round the ulna.

Question 36

What is the surface marking of the femoral artery and saphenous opening?

Answer 36

Femoral artery, (within 1.5cm of) the point half way between the pubic tubercle and the anterior superior iliac spine.
Saphenous opening, 3cm below and lateral to the pubic tubercle. Medial to the femoral artery 3cm below the inguinal ligament.

Question 37

What is the order of the femoral artery, vein and nerve in the groin?

Answer 37

Nerve lateral and vein medial. (Artery between them!)

drive van away from genitals

Question 38

Which vein becomes the superficial femoral vein?

Answer 38

Popliteal vein as it passes through the adductor canal.

Question 39

What is the motor and sensory supply of the femoral nerve?

Answer 39

Motor, anterior compartment of the thigh. Sensory, anterior thigh skin, hip and knee joint.

Question 40

5 What are the attachments of the adductor muscles?

Answer 40

All have an origin on the pubis, all insert onto the femur.

Question 41

Which nerve supplies the adductor muscles?

Answer 41

Obturator nerve.

Question 42

What passes through the adductor canal?

Answer 42

Superficial femoral artery, popliteal vein.

Question 43

What is the function of the hip extensors and which is the most powerful?

Answer 43

Gluteus maximus is the most powerful hip extensor, it is used for climbing up hill/stairs.

Question 44

Which muscles abduct the hip and when is abduction vital to normal function?

Answer 44

Gluteus minimus and medius. They hold the pelvis horizontal during walking when one leg if off the ground.

Question 45

What structures pass through the greater sciatic foramen?

Answer 45

Sciatic nerve, piriformes muscle, superior and inferior gluteal vessels, peudendal nerves (to perineum).

Question 46

Is the ischial spine palpable in the living? If so, how do you palpate it?

Answer 46

Yes, through the vagina or rectum.

Question 47

Where is the surface marking of the sciatic nerve and why is this important?

Answer 47

Lower inner quadrant of the buttock. Drug injection into muscle is common, injection into the nerve can completely destroy it.

Question 48

If the sciatic nerve is completely cut which parts of the lower limb will still have a nerve supply?

Answer 48

Anterior and medial muscle compartments of the thigh. Sensation from the medial dorsum of the foot up the anteromedial calf (saphenous nerve, branch of femoral). Sensation from the anterior and medial thigh (femoral and obturator nerves).

Question 49

Which major vessels supply the buttock with blood?

Answer 49

The superior and inferior gluteal arteries, both branches from the posterior branch of the internal iliac artery.

Question 50

Which nerves supply the anterior and lateral compartments of the leg? (remember that the leg is from knee to ankle)

Answer 50

Anterior compartment is the deep branch of the common peroneal (FIBULAR) and lateral is the superficial branch

Question 51

Where are these nerves at risk of damage?

Answer 51

Where they run against the neck of the fibula just under the skin.

Question 52

Which artery supplies the anterior compartment of the leg?

Answer 52

Anterior tibial artery.

Question 53

How many extensor tendons are there to each of the toes? Where do they originate?

Answer 53

Two tendons to each of the toes, a longus tendon from a muscle in the anterior leg (which is attached to the fibula and interosseous membrane) and a brevis tendon from a muscle in the foot (attached to the dorsum of the calcanium and surrounding ligaments in the lateral foot). (The brevis tendon to the little toe is often absent).

Question 54

Where are the palpable pulses in the leg?

Answer 54

Behind the knee between heads of gastrocnemius (popliteal). Posterior to the medial malleolus (posterior tibial). Between the extensor tendons of the hallux and the second toe (dorsalis pedis)

Question 55

Why is the tibia prone to poor fracture healing?

Answer 55

Bones have nutrient arteries to supply the marrow but also receive a significant amount of blood from blood vessels which run from the muscles which are attached to the bone. The tibia is relatively devoid of muscle attachment (none on the subcutaneous surface) which means it has a poor blood supply and poor healing.

Question 56

Describe the movements at the ankle joint?

Answer 56

The ankle joint is between the tibia/fibula mortice and the talus. The only movement possible at this joint is dorsi flexion and plantar flexion (extension and flexion).

Question 57

What would be the effect of damage to the common peroneal (fibular) nerve?

Answer 57

Paralysis of all muscles in the anterior and lateral compartments of the leg. Loss of sensation down the lateral leg from the knee to the ankle and onto the dorsum of the foot including the dorsum of the medial four toes.

Question 58

Which muscles attach to the Achilles tendon?

Answer 58

Gastocnemius, soleus, plantaris.

Question 59

What is the nerve supply of the posterior compartment?

Answer 59

Tibial nerve; a branch of the sciatic nerve.

Question 60

Where does the long saphenous vein start and what is its route up the limb?

Answer 60

It starts at the medial end of the dorsal venous arch on the dorsum of the foot. It runs upwards anterior to the medial malleolus usually just lateral to the tibialis anterior tendon. It continues up the anteromedial calf and passes more posteriorly round the knee joint, lying directly over sartorius. It continues superficial to sartorius into the upper thigh tot the apex of the femoral triangle where it lies superficial to the femoral vein which it joins about 3cm below the inguinal ligament.

Question 61

What is the action of the peroneal muscles?

Answer 61

Longus and brevis; ankle flexion and eversion at the subtalar joint. Tertius; ankle dorsi flexion (extension) and eversion at the subtalar joint.

Question 62

How many flexor tendons does each toe have and what are the origins?

Answer 62

) One tendon to the hallux from a muscle attached to the fibula. Two tendons to each of the other toes; a longus tendon from a muscle attached to the tiba and a brevis tendon with a muscle attached to the calcaneum.

Question 63

What are the layers of the sole of the foot?

Answer 63

a) Superficial layer lies just deep to the plantar fascia it contains abductor hallucis brevis, flexor digitorum brevis and abductor digiti minimi,
b) Tendons of flexor hallucis longus and flexor digitorum longus and the muscles attached to these tendons; lumbricles and quadratus plantae (flexor accessorius).
c) Small muscles of the hallux and liitle toe; flexor halluces brevis, adductor halluces and flexor digiti minimi brevis.
d) Interossei muscles, plantar and dorsal.

Question 64

What is the importance of the deep veins and their valves?

Answer 64

The deep veins transmit blood back to the heart and work using muscle pumps. The valves only allow blood to flow uo the vein and from the ouside of the leg to the inside. When a muscle is relaxed the deep veins fill with blood, when the muscle contracts the blood is pumped further up the vein.

Question 65

At which joints does flexion, extension, inversion and eversion of the ‘ankle’ take place?

Answer 65

Flexion and extension take place at the joint between the tibia/fibula and the talus. Inversion and eversion take place at the joint between the talus and calcaneum which lies below the talus (subtalar joints).

Question 66

Which anatomical features maintain the arches of the foot?

Answer 66

a) Shape of the bones. The bones are wedge shaped which helps support the arch
b) Tendons coming from the leg pulling the arch upwards
c) Strong ligaments running between the bones on the plantar surface which complement the support given by the shape of the bone
d) Plantar ligament/fascia hold the front and back of the foot closer together

Question 67

Describe the blood supply to the head of the femur?

Answer 67

(my answer)

Medial circumflex femoral artery

Question 68

Which nerves supply the hip joint?

Answer 68

The rule for nerve supply to a joint is; The nerve supplying a joint with sensation is the same as the nerve supplying the muscles which move the joint. So for the hip joint the answer is femoral (eg. rectus femoris), obturator (adductors) and tibial component of the sciatic (hamstrings).

Question 69

What are the functions of the cruciate ligaments and how you would test them?

Answer 69

The anterior cruciate stops the tibia moving forwards relative to the femur; it is tested by placing the knee at 20-30 degree of flexion (where the anterior cruciate is taught) and trying to pull the tibia forwards – there should be no movement (Lachman test). The posterior cruciate stops the tibia moving backwards relative to the femur; it is tested by placing the knee in 90 degree flexion and pushing the tibia backwards. Unlike the Lachman test there is normally some movement in this position and a judgement has to be made as to whether it is too much movement; there is often a normal knee on the other leg to compare!!

Question 70

What mechanisms reduce the risk of dislocation of the patella?

Answer 70

There is normally an angle between the femur and tibia of about 175 degrees. This means that when quadriceps pulls the patella tends to move outwards and may dislocate laterally. To resist this movement the lateral part of the patella grove on the femur is more prominent and the lowest fibres of vastus medialis are almost horizontal to pull the patella medially.

Question 71

Describe the ligaments of the medial and lateral malleolus.

Answer 71

Medially there is a large ligament arising on the lower tibia which sends fibres in a fan shape to attach in front, below and behind the distal end of the tibia onto the bones of the foot; this is the deltoid ligament. Laterally there are three separate ligaments which arise on the inferior end of the fibula; they pass anteriorly, inferiorly and posteriorly to attach to bones of the foot (anterior talo-fibular, calcaneo-fibular and posterior talo-fibular ligaments respectively).