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MSK > Session 4 > Flashcards

Session 4 Flashcards

1
Q

Identify the bones of the wrist & hand, including the carpal bones on the intact skeleton, & on radiological images LO

  1. The bones of the hand provide support & flexibility to the soft tissues. They can be divided into three categories:
A
  1. Carpal bones (Most proximal) – A set of eight irregularly shaped bones. These are located in the wrist area.

Metacarpals – There are five metacarpals, each one related to a digit

Phalanges (Most distal) – The bones of the fingers. Each finger has three phalanges, except for the thumb, which has two.

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2
Q

The carpal bones are a group of eight, irregularly shaped bones. They are organised into two rows – proximal & distal.

  1. In the proximal row, the bones are (lateral to medial):
  2. Distal row bones are lateral to medial
A
  1. Scaphoid

Lunate

Triquetrum

Pisiform – A sesamoid bone, formed within the tendon of the flexor carpi ulnaris

  1. Trapezium

Trapezoid

Capitate

Hamate – has a projection on its palmar surface called the hook of hamate

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3
Q
A
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4
Q
A
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5
Q

Describe the extrinsic & intrinsic muscles of the hand, their origins,

insertions, nerve supply & function LO (MSK session 3)

Describe the boundaries & contents of the carpal tunnel MSK session 3

A
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6
Q

Describe the blood supply of the hand, including the palmar arches LO

A
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7
Q

Clinical relevance:

A
  • Arterial Blood Gas
  • Vascularity – Allen’s test
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8
Q

What is tendon avulsion (not LO)

A

An avulsion fracture is a bone fracture which occurs when a fragment of bone tears away from the main mass of bone as a result of physical trauma.

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9
Q

Describe Allen’s test & know how to interpret the result LO

  1. Allens test:
  2. Modified Allens test:

3.

4.

A
  1. The patient is asked to clench both fists tightly for 1 minute at the same time.

Pressure is applied over both radial arteries simultaneously so as to occlude them.

The patient then opens the fingers of both hands rapidly, and the examiner compares the colour of both. The initial pallor should be replaced quickly by rubor.

The test may be repeated, this time occluding the ulnar arteries.

Allen’s test looks for abnormal circulation. If color returns quickly as described above, Allen’s test is considered to demonstrate normal circulation. If the pallor persists for some time after the patient opens their fingers, this suggests a degree of occlusion of the uncompressed artery.

2.The hand is elevated and the patient is asked to clench their fist for about 30 seconds.

Pressure is applied over the ulnar and the radial arteries so as to occlude both of them.

Still elevated, the hand is then opened. It should appear blanched (pallor may be observed at the finger nails).

Ulnar pressure is released while radial pressure is maintained, and the colour should return within 5 to 15 seconds.

If color returns as described, Allen’s test is considered to be normal. If color fails to return, the test is considered abnormal and it suggests that the ulnar artery supply to the hand is not sufficient. This indicates that it may not be safe to cannulate or needle the radial artery.

3.

4.

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10
Q

Describe the cutaneous distribution of the ulnar, median & radial nerves LO

A
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11
Q
  1. Rheumatoid arthritis of the wrist, metacarpophalangeal joints (MCPJs) & proximal interphalangeal joints (PIPJs) usually LO
  2. Symptoms
  3. Other along the line issues
A
  1. RA attacks joints -> inflamed synovial membrane -> cartilage damage & bone loss
  2. Stiffness, worse in the mourning, pain &swelling between wrist joint/ MPJ/ IPJ, can cause tendons to become inflamed, hand deformity (see pic),
  3. Boutonnière, CTS, swannneck deformities, tenosynovitis,
  4. NSAIDS, DMARDS, fusion of carpal bones
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12
Q
  1. Osteoarthritis of the 1st CMC joint LO

Occurs when

  1. Common symptoms
  2. Advanced symptoms
  3. What is a key sign when you get distal interphalangeal joints (DIPJs) osteoarthritis?
  4. Symptoms
  5. What do you normally see in x rays of patients with osteoarthritis
A
  1. cushioning cartilage of the joint surfaces wears away, resulting in damage of the joint
  2. Pain at the base of the thumb, loss of strength of the thumb, base of thumb swollen & inflamed,
  3. zigzag’ deformity, is characterized by a deviation of the thenar eminence towards the middle of the hand, whilst the thumb phalanges overextend, crepitus
  4. Heberden nodes, (palpable osteophytes) in the DIP joints, are more characteristic in women than in men
  5. Symptoms are the same, e.g. Reduced range of motion, crepitus, stiffness in the mourning, pain
  6. joint space narrowing, subchondral sclerosis, cysts & osteophyte
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13
Q

CTS

  1. Treatments
  2. Controversial
  3. Presentation
A
  1. • Treatable causes • Splints • Steroid injections • surgery
  2. • Physio /stretches • Nsaids
  3. • p/n • Distribution • Worse at night • numbness
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14
Q
  1. What is a 5th metacarpal (Boxer’s) fracture? LO
  2. What is the pattern of fracture?
A
  1. fracture of one of the metacarpal bones of the hand.
  2. Classically, the fracture occurs transversely across the neck of the bone, after the patient strikes an object with a closed fist.
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15
Q

De Quervain’s tenosynovitis

  1. Tenosynovitis?
  2. Symptoms
  3. Tests & treatments
  4. Signs (when cause is due to infection)
  5. What is De Quervain’s tenosynovitis LO
  6. Symptoms

7.

A
  1. inflammation of the fluid-filled sheath (called the synovium) that surrounds a tendon.
  2. pain, swelling and difficulty moving the particular joint where the inflammation occurs.
  3. Finklesteins test & Steroid / splint / surgery
  4. Finger held in slight flexion.
    Fusiform swelling.
    Tenderness along the flexor tendon sheath.
    Pain with passive extension of the digit.
  5. Inflammation of tendons on the side of the wrist at the base of the thumb. These tendons include the extensor pollicis brevis & the abductor pollicis longus tendons, which extend the joints of the thumb
  6. Pain, tenderness, swelling, sometimes clicking
    7.
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16
Q
  1. What is Guyon’s canal LO
  2. Symptoms
  3. Commonly occurs in
  4. Differential cause
A
  1. Compression of the ulnar nerve as it passes through Guyon’s canal
    • pins & needles in the ring & little finger -> loss of sensation in medial 1.5 fingers
      - loss of motor function of muscles innervated by ulnar I.e. All muscles except LOAF
  3. cyclists
  4. Cubital tunnel syndrome
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17
Q

Dupuytrens contracture LO

  1. What is it?
  2. Cause
  3. Finger most effected ?
  4. Signs & symptoms

5.

6.

Functional deficit

  • PIPJ contracture >30 degrees
  • Collagenase

Early trials encouraging Learning curve

Locals trials due soon Not a cure for dupuytrens

A
  1. a flexion contracture of the hand due to a palmar fibromatosis, in which the fingers bend towards the palm & cannot be fully extended (straightened).
  2. It is an inherited proliferative connective tissue disorder that involves the hand’s palmar fascia.
  3. Ring
  4. nodule, painless loss of range of motion,
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18
Q

Reflex sympathetic dystrophy LO

  1. What is it?
  2. Clinical features
  3. Symptoms
  4. My have these symptoms
A
  1. rare disorder of the sympathetic nervous system that is characterized by chronic, severe pain.
  2. neurogenic inflammation (swelling in the central nervous system), nociceptive sensitisation (which causes extreme sensitivity or allodynia), vasomotor dysfunction (blood flow problems which cause swelling and discolouration) and maladaptive neuroplasticity (where the brain changes and adapts with constant pain signals);
  3. pain sensations, including burning, stabbing, grinding, & throbbing.
  4. spasms; local swelling; extreme sensitivity to things such as wind and water, touch and vibrations; abnormally increased sweating; changes in skin temperature (usually hot but sometimes cold) and color (bright red or a reddish violet); softening and thinning of bones; joint tenderness or stiffness; changes in nail and hair growth and/or restricted or painful movemen
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19
Q
  1. As the snuffbox is triangularly shaped, it has three borders, a floor, & a roof:
  2. It is important to note that the ? of the muscles form the borders, not the muscles themselves.
  3. Contents (3)
  4. How does the radial artery move in the anatomical snuffbox?
  5. Subcutaneously, terminal branches of the superficial branch of the radial nerve run across the roof of the anatomical snuffbox, providing innervation to the skin of the lateral ? digits on the dorsum of the hand, and the associated palm area.
  6. Also subcutaneously, the cephalic vein crosses the anatomical snuffbox, having just arisen from the ? venous network of the hand.
A
  1. Ulnar (medial) border: Tendon of the extensor pollicis longus.

Radial (lateral) border: Tendons of the abductor pollicis longus & extensor pollicis brevis.

Proximal border: Styloid process of the radius.

Floor:

Carpal bones; scaphoid & trapezium

Roof: Skin.

  1. tendons
  2. radial artery, a branch of the radial nerve, & cephalic vein
  3. Crosses the floor, oblique manner, deep to the extensor tendons. The radial pulse can be palpated in some individuals by placing two fingers on the proximal portion of the anatomical snuffbox.
  4. 3 1/2
  5. dorsal
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20
Q
A
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21
Q
  1. As the snuffbox is triangularly shaped, it has three borders, a floor, & a roof:
  2. It is important to note that the ? of the muscles form the borders, not the muscles themselves.
  3. Contents (3)
  4. How does the radial artery move in the anatomical snuffbox?
  5. Subcutaneously, terminal branches of the superficial branch of the radial nerve run across the roof of the anatomical snuffbox, providing innervation to the skin of the lateral ? digits on the dorsum of the hand, and the associated palm area.
  6. Also subcutaneously, the cephalic vein crosses the anatomical snuffbox, having just arisen from the ? venous network of the hand.
A
  1. Ulnar (medial) border: Tendon of the extensor pollicis longus.

Radial (lateral) border: Tendons of the abductor pollicis longus & extensor pollicis brevis.

Proximal border: Styloid process of the radius.

Floor:

Carpal bones; scaphoid & trapezium

Roof: Skin.

  1. tendons
  2. radial artery, a branch of the radial nerve, & cephalic vein
  3. Crosses the floor, oblique manner, deep to the extensor tendons. The radial pulse can be palpated in some individuals by placing two fingers on the proximal portion of the anatomical snuffbox.
  4. 3 1/2
  5. dorsal
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22
Q

Radial artery in the anatomical snuffbox

A
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23
Q

Extensor digitorum (On the dorsum of each finger, you should note the insertion of the central slip of the extensor digitorum into the ? & the insertion of the two lateral slips into the ?).

A

base of the valve middle phalanx

base of the distal phalanx

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24
Q

Understand the mechanical properties of cartilage & bone

A
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25
Q

To be able to integrate anatomical knowledge & apply this to clinical cases, including:

  • traumatic median nerve division at the wrist
  • carpal tunnel syndrome
  • ulnar nerve lesion at the wrist
  • ulnar verve lesion at the elbow
A
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26
Q

Understand the vasculature & innervation of bones and the consequence

of loss of arterial supply (avascular necrosis) LO

  1. What is avascular necrosis?
  2. Synonyms:
  3. Varied causes:
  4. Leads to ?
A
  1. Death of bone due to interruption (reduced) of

blood supply

  1. osteonecrosis, aseptic necrosis, ischaemic necrosis
  2. Fracture, dislocation, steroid use, radiation, decompression

sickness (‘the bends’) etc.

  1. collapse of necrotic

segment & secondary osteoarthritis

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27
Q
A
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28
Q

Joints

  1. What is a joint?
  2. Structural classification depends on ?
  3. Functional classification according to ? not required for

this course.

A
  1. Articulation between two or more bones
  2. (tissue between

bones)

– Fibrous

– Cartilaginous

– Synovial

  1. degree of movement
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29
Q

Types of joints:

A
  1. Fibrous

o Sutures - joining of the cranial bones

o Gomphosis - a peg in a socket like teeth

o Syndesmosis - like the interosseus membrane between the radius & ulna, tibiofibular joint

  1. Cartilaginous

o Synchondrosis – hyaline cartilage fusion - an epiphyseal growth plate

o Symphysis – fibrocartilaginous fusion – interverebral disc & pubic

symphysis

  1. Synovial

o Plane – permits gliding / sliding – acromioclavicular joint

o Hinge – permits only flexion and extension – elbow joint

o Saddle – permits movement in one plane and limited movement in another – 1st carpometacarpal joint

o Ball & Socket – shoulder

o Condyloid – permits flexion/extension, adduction/abduction & circumduction –

wrist joint, metacarpophalangeal joint, metatarsophalangeal joints

o Pivot - Atlantoaxial joint (between 1st & 2nd cervical vertebrae)

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30
Q

Name all these types of synovial joints

A

1: Ball & socket joint;
2: Condyloid joint (Ellipsoid);
3: Saddle joint;

4 Hinge joint;

5: Pivot joint;

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31
Q

Classify joints according to the tissues lying between the bones & describe

the features of each type of joint LO

  1. What type of joints are seen in the image?
  2. Give examples of this type of joint image in the body
A
  1. Fibrous joints
  2. • Sutures of skull
  • Inferior tibiofibular joint
  • Radioulnar interosseous membrane
  • Posterior sacroiliac joint
  • Joint between roots of tooth & bone of mandible/ maxilla
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32
Q
  1. What type of joint is this?
A
  1. Primary cartilaginous joint

United by hyaline cartilage e.g. 1st sternocostal joint, xiphisternal joint, epiphyseal growth plates

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33
Q

What type of joint is this?

Give examples

A

Secondary cartilaginous joint (symphysis)

– Articulating bones covered with hyaline cartilage with a pad of fibrocartilage between them – e.g. symphysis pubis, intervertebral disc, manubriosternal joint

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34
Q

What type of joint is this?

Give examples

A

Synovial joint (Joint cavity containing synovial fluid)

Freely movable

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35
Q

Classify joints according to the tissues lying between the bones & describe

the features of each type of joint

  1. Characteristic features of synovial joints
A
    • Articular cartilage
      - Fibrous capsule
      - Synovial membrane
      - Synovial fluid
      - Intra articular menisci
      - Fat pads
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36
Q

Articular cartilage

  1. Formed by?
  2. Function
A

1.Hyaline cartilage (exceptions are acromioclavicular, sternoclavicular,

temporomandibular → atypical synovial joints →fibrocartilage)

  1. Smooth, low friction movement Resists compression
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37
Q

Fibrous capsule

  1. Made of?
  2. Function
A
  1. Collagen (longitudinal & interlacing bundles)
  2. Completely encloses joint except where interrupted by synovial protrusions (e.g. obturator externus bursa at posterior aspect of hip joint)

• Stabilises joint: permits movement but resists dislocation

38
Q

Synovial membrane

  1. Thin ?- vascularised membrane
  2. Lines ?
  3. Does not cover
  4. Function
A
  1. highly
  2. capsule, covers exposed osseous surfaces, tendon sheaths, bursae
  3. articular cartilage/ intra-articular discs / menisci
  4. Produces synovial fluid
39
Q

Describe the structure & function of bursae & tendon sheaths LO

  1. Structure of bursa
  2. Function
  3. Structure of tendon sheaths
  4. Function
A
  1. • sac lined with synovial membrane
  • filled with synovial fluid
  • communicating or non-communicating (with joint cavity)
  1. It provides a cushion between bones & tendons and/or muscles around a joint. This helps to reduce friction between the bones & allows free movement.
  2. • elongated bursa

• wrapped around a tendon

It has two layers:

synovial sheath

fibrous tendon sheath

  1. It permits the tendon to stretch & not adhere to the surrounding fascia.
40
Q
A
41
Q
A
42
Q

Synovial fluid

  1. Describe its appearance & texture
  2. Fluid volume <0.5ml in large joint e.g. knee
  3. Composition:
  4. Functions:
A
  1. Clear or pale yellow, viscous, slightly alkaline at rest
  2. hyaluronic acid, lubricin, proteinase, collagenase
  3. reduces friction, shock absorption, nutrient & waste transportation
43
Q

Intra-articular menisci / discs

What does it look like?

A

Fibrocartilage – not covered by synovium

44
Q

Fat pads

A
45
Q

Describe the blood supply to synovial joints (4)

A
  • Periarticular arterial plexus (circulus arteriolus vasculosus)
  • Articular cartilage is avascular
  • Fibrous capsule & ligaments have poor blood supply
  • Synovial membrane has rich blood supply
46
Q

Nerve supply Hilton’s law:

A

The nerves supplying the joint capsule also supply the muscles moving the joint & the skin overlying the insertions of these muscles

47
Q

Classify synovial joints into the different subtypes & be able to describe the movements at these joints LO

A
48
Q

Describe movement at the planar joint & give examples LO

A
  • Articulating surface: flat or slightly curved
  • Gliding or sliding movements
  • Non-axial (no axis of movement)
  • Sternoclavicular joint, acromioclavicular joint, intercarpal joints, vertebral facet joints.
49
Q

Describe movement at the hinge joint & give examples LO

A
  • Uniaxial / monaxial: like door hinge
  • Pulley-shaped: Convex surface of one bone fits into concave surface of another
  • Examples: knee, ankle, humeroulnar joint of elbow
50
Q

Describe movement at the pivot joint & give examples LO

A
  • Uniaxial / monaxial joint
  • Rounded or pointed surface of one bone articulates within ring formed by the concavity of another bone and a fibrous ligament
  • Examples: proximal radioulnar joint, atlantoaxial joint
51
Q

Describe movement at the condyloid / ellipsoidal joint & give examples LO

A
  • Biaxial joint: oval shaped condyle of one bone rests on elliptical cavity of another
  • Movements: flexion, extension, abduction, adduction (and circumduction)
  • Example: metacarpophalangeal joints, radiocarpal (wrist) joint, atlanto-occipital joint
52
Q

Describe movement at the saddle joint & examples LO

A
  • Biaxial joint
  • Articular surfaces: one bone is saddle shaped (concavoconvex), the other bone resembles the legs of the rider
  • Movements: flexion, extension, adduction, abduction, (circumduction)
  • Examples: 1st carpometacarpal joint
53
Q

Describe movement at the ball & socket joint & examples LO

A
  • Multiaxial / polyaxial
  • Ball-like surface of one bone fits into cup-like surface of another
  • Movements: flexion, extension, abduction, adduction, (circumduction) & rotation
  • Examples: hip, shoulder, incudostapedial joint (middle ear)
54
Q

Understand the factors that limit movement at a joint LO

Understand the factors contributing to stability of joints LO

  1. Factors effecting stability & range of motion:
A
  1. • Structure / shape of articulating bones
  • Strength & tension of joint ligaments
  • Arrangement & tone of muscles
  • Apposition of neighbouring soft tissues
  • Hormones e.g. relaxing in pregnancy
  • Use / disuse
55
Q

Cracking your joints theory not LO

A
  • Bones are pulled away from each other
  • Synovial cavity expands
  • Synovial fluid volume stays constant
  • Partial vacuum produced
  • Gases dissolved in synovial fluid are pulled out of solution
  • Makes a popping sound
56
Q

Describe the effects of ageing on joints LO

A
  • Decreased production of synovial fluid
  • Thinning of articular cartilage
  • Shortening of ligaments & decreased flexibility
  • Degenerative changes
57
Q
  1. What is arthritis?
  2. Symptoms:
  3. Signs:
  4. Most common:
A
  1. Inflammation & stiffness of a joint

• >100 different forms

  1. Symptoms: pain, swelling, stiffness
  2. Signs: redness, swelling, deformity, tenderness, reduced range of movement (ROM), abnormal gait 4. osteoarthritis – ‘wear & tear’
58
Q

Here is a normal knee, draw a knee with osteoarthritis

A
59
Q

Rheumatoid arthritis

  1. What is it?
  2. Results in?
  3. Peak age ?
  4. ? more commonly affected than ? 2-3:1

• 1% of population

A
  1. Autoimmune disorder, Autoantibodies (rheumatoid factor) attack the synovium → synovial inflammation (pannus)
  2. Joint erosion & deformity: MCPJ & PIPJ of hands, cervical spine, feet, can involve large joints

• Damage to other organs

– Eyes – Skin – Lungs – Heart & blood vessels – Kidneys – Blood

  1. 40-50 years (can be juvenile)
  2. Women, men
60
Q
A
61
Q

X-ray features of RA:

A
  • Narrowing of joint space
  • Periarticular osteopenia
  • Juxta-articular bony erosions (in non-cartilage protected bone)
  • Subluxation & gross deformity
62
Q

Functions of the skeleton

A
  • Support
  • Protection
  • Movement
  • Mineral & GF storage
  • Haematopoeisis
63
Q

Describe the structure of a long bone

Primarily compact bone but may have spongy bone at extremities

Terminology:

  • Diaphysis
  • Metaphysis
  • Growth / epiphyseal plate
  • Epiphysis
  • Articular cartilage
  • Periosteum
  • Endosteum
  • Medullary cavity (red/yellow)
  • Nutrient artery
A
64
Q

Structure of short, flat & sesamoid bones

  1. Examples of short bones
  2. Consist mainly of
  3. Thin layer of
  4. No ?
A
  1. carpal & tarsal bones
  2. spongy bone
  3. periosteum-covered compact bone on outside
  4. epiphysis or diaphysis
  5. Contain bone marrow between the

trabeculae

65
Q
  1. ELECTIVE means
  2. TRAUMA means
A
  1. chronic injuries
  2. acute injuries

– Advances in hand fracture fixation

– Mangled injuries

66
Q
  1. What is tennis elbow ?
  2. Cause
A
  1. Sore & tendor at the lateral epicondyle, forearm muscles and tendons become damaged from repetitive overuse
67
Q

Ulnar nerve lesion at the wrist & elbow LO

A

Should be ABductor digiti minimi

68
Q

Ulnar nerve lesion at the elbow LO

  1. How it commonly occurs:
  2. Motor functions: Which muscles become paralysed? (4)

Flexion of the wrist can still occur, but is accompanied by ?

  1. Sensory functions:
  2. Characteristic signs:
A
  1. Medial epicondyle fracture (& supracondylar fracture)
  2. Flexor carpi ulnaris and medial half of flexor digitorum profundus paralysed.

abduction

The interossei are paralysed, so abduction and adduction of the fingers cannot occur. Movement of the little and ring fingers is greatly reduced, due to paralysis of the medial two lumbricals.

  1. Two of these branches arise in the forearm, & travel into the hand:

Palmar cutaneous branch: Innervates the skin of the medial half of the palm. Dorsal cutaneous branch: Innervates the skin of the medial one and a half fingers, and the associated dorsal hand area.

The last branch arises in the hand itself:

Superficial branch – Innervates the palmar surface of the medial one & a half fingers.

  1. Patient cannot grip paper placed between fingers.
69
Q

Damaged at the Wrist

  1. How it commonly occurs:
  2. Motor functions: which muscles are paralysed & what is the effect ?
  3. Characteristic signs:
  4. Why is there ulnar Claw Hand- on attempted finger extension?
A
  1. Lacerations to the wrist
  2. The palmar branch and superficial branch are usually severed, but the dorsal branch is unaffected. Sensory loss over palmar side of medial one and a half fingers only.
  3. Patient cannot grip paper placed between fingers. For long-term cases, a hand deformity called ‘Ulnar Claw’ develops.
  4. • Hyperextension at the MCP and flexion of the

distal and proximal IP joints of the 4th and 5th digits.

  • Due to:
  • Loss of innervation to the 3rd and 4th lumbricals These flex at the MCPJ and extend at the IP joint.
  • There is hypertension at the MCPJ due to unopposed action of the extensor digitorum and extensor digiti minimi.
  • The proximal and distal IP joints are flexed due to unopposed flexion from the flexor muscles of the anterior compartment of the arm.
70
Q

How to differentiate between a distal/ proximal lesion

A

Ulnar Paradox

  • Long-standing damage to the ulnar nerve at the elbow results in less clawing as compared to similar lesion at the wrist.
  • In a high ulnar nerve lesion, there is paralysis of the ulnar/medial half of flexor digitorum profundus (flexion at the distal IP joint and little fingers), & flexor carpi ulnaris.
  • Therefore, there will not be any flexion at the distal IPJ of the ring & little finger reducing the appearance of the claw.

Maybe more radial deviation

71
Q

Flexor digitorum profundus is innervated y both ulnar & median nerves

Flexor digitorum superficialis has 3 origins

A
72
Q

CTS tests

A
  • Positive Phalen’s test: flexing the wrist for 60 seconds causes pain or paraesthesia in the median nerve distribution.
  • Positive Tinel’s sign: tapping lightly over the median nerve at the wrist causes a distal paraesthesia in the median nerve distribution.
73
Q

Median nerve

Why can superficial lacerations at the wrist result in loss of sensation in the palm but not the digits?

A

• At the wrist, the median nerve becomes superficial in the midline & gives off a palmar cutaneous branch which supplies the skin of the mid-palm. The digitial nerves arise from the median & ulnar nerves and hence are spared in a superficial laceration.

74
Q

Musculocutaneous

A
75
Q

Axillary

A
76
Q
A
77
Q

Name all the muscles of the posterior forearm innervated by the radial nerve

A
78
Q
A
79
Q
A
80
Q

Common extensor tendon

A tendon that attaches to the lateral epicondyle of the humerus.

Serves as the upper attachment (in part) for the superficial muscles of the posterior aspect of the forearm:

A
  • Extensor carpi radialis brevis
  • Extensor digitorum
  • Extensor digiti minimi
  • Extensor carpi ulnaris
81
Q

Extensor Digitorum

NB the insertion of the central slip of the extensor digitorum into the

? & the insertion of the two lateral slips into the ?

A

base of the middle phalanx

base of the distal phalanx

82
Q
A
83
Q
A
84
Q

Supinator has two heads!!!

A
85
Q
A
86
Q
A
87
Q
A
88
Q
A
89
Q
A
90
Q
A
91
Q
A

MSK (7 decks)

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