MSK 3 Flashcards

1
Q

Insertions of BBC muscles

A

Brachialis - coronoid process of ulna
Biceps brachii - radial tuberosity
Coracobrachialis - Coracoid process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Attachments of long and short head of biceps brachii

Which tendon is most likely to rupture and what is this called

A

Short head into Coracoid process
Long head into superglenoid fossa of scapula

Long head most likely to rupture - called Popeyes sign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Names of the heads of triceps brachii - nerve innervation with roots

A

Medial, short and lateral

Innervated by radial nerve C5-T1 and long head also innervated by Axillary nerve C5 and C6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What nerve root does the triceps tendon hammer reflex test for

A

C7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where does the long head of the triceps originate from?

A

Infraglenoid fossa of the scapula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Borders of the cubital fossa

A

Superior - imaginary line between the medial and lateral epicondyles
Medial - lateral border of pronator teres
Lateral - medial border of brachioradialis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Contents of the cubital fossa

A

Tendon of biceps brachii
Brachial artery
Median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

2 ways that the glenohmeral joint is made stable

A

Ligaments

  • glenohumeral ligament
  • transverse humeral ligament
  • coracohumeral ligament
  • Coracoacromial ligament

Tonic tone of the SITS muscles

Glenoid labrum making the joint deeper

Fibrous capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two bursae of the glenohumeral joint

A

Sub acromial bursae - between Supraspinatous tendon and acromion
Subscapular bursae - bursae between the subscapular tendon & scapula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Ligaments of the glenohumeral joint. Briefly describe their location and where they span between

A
  1. Transverse humeral ligament.
    • across the greater and lesser tubercle of humerus and holds tendon of long head of biceps in place during movement
  2. Coracoacromial ligament
    • across the Coracoid process and acromion
    • ligament plus acromion and Coracoid process form an arch
      • Coracoacromial arch - prevents superior displacement of humerus
  3. Glenohumeral ligament
    • from glenoid fossa to the anatomical neck of humerus
  4. Coracohumeral
    • from Coracoid process to the anterior surface of greater tubercle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Painful arc - what is it and how is it tested

A

Subacromial bursitis - inflammation of this bursae. Supraspinatus tendon becomes irritated and degeneration occurs of the tendon

Upon abduction, when the affected portion of the tendon comes into contact with the acromion, it hurts - hence painful arc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why are most shoulder dislocations anterior and inferior?
What structures are at risk in these dislocations.
What is it anterior and inferior in relation to?

A

Location is in relation to infraglenoid fossa.
This dislocation is more common because there are no SITS muscles here to stabilise it and this is the weakest part of the joint capsule.
Axillary nerve runs here as well as anterior and posterior circumflex arteries so these structures are at risk.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the major land marks for the arterial supply of the upper limb

A

Left hand side

  • subclavian artery direct branch off the aortic arch
  • becomes the Axillary artery as it passes the lateral border of 1st rib
  • Axillary artery passes the into upper limb in the axillary sheath below pec minor
  • surgical neck of humerus - anterior and poster Cx artery arise
  • lower border of teres major, Axillary becomes brachial artery
  • gives off profunda brachii for the posterior supply of the arm
  • brachial artery bifurcates into radial and ulna artery as it crosses cubital fossa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where do the limb buds appear in the foetus? Put timings on it

A

End of week 4, upper limb buds appear on the ventrolateral body wall.
A few days later the lower limb buds appear too, a bit lower down.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

From which embryonic tissues do the limbs generate from

A

Mesoderm (flexible)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What covers the the distal borders of the limb buds and what structure does this become

A

Ectoderm

Forms the Apical Ectodermal Ridge

17
Q

What is the function of the AER?

A
  • keeps the adjacent mesenchyme undifferentiated but they proliferate.
  • proliferation = growth so the cells get further away from the AER
    • AER becomes more distal and loses its effect on the proximal cells
  • the more proximal cells then differentiate into cartilage and muscle.
18
Q

How do fingers and toes form from the hand and foot plates

A

Cell death occurs which separates them into fingers as we know them

19
Q

What marks the boundary between dorsal and ventral ectoderm?

A

AER

20
Q

What is the zone of polarising activity and what does it do

A

It is a cluster of cells that is located on the posterior base of the limb bud.
It is responsible for asymmetry of the limb (eg ensures the thumb is lateral in the hand) and ensures an anterior posterior axis.
It also maintains the AER.

21
Q

Which weeks of the foetal development are the most critical for limb defects?

A

4 to 6

22
Q

What is syndactyly

A

Fusion of digits.
Occurs when the apoptosis in the cartilaginous digital rays fails.
Fusion can be due to skin, connective tissue or even bone.

23
Q

What is polydactyly

A

Extra digit (s)

24
Q

What is Amelia

A

A complete absence of a limb

25
Q

What is meromelia

A

Partial absence of a limb

26
Q

What is phocomelia

A

This is a subset of meromelia.

Rudimentary hands and feet are connected to the truth via weak, misshaped bones.

27
Q

Name a drug that is known to have caused phocomelia.

A

Thalidomide

28
Q

Explain how in the upper limb, the thumb is lateral and the extensors are posteriorly, but in the lower limb the great toe is medial and the extensors are anterior

A

Limb rotation occurs

  • UL rotates 90 degrees laterally
  • LL rotates 90 degrees medially
29
Q

Name the positions of the muscles in the anterior compartment of the arm, relative to each other

A

Coracobrachialis - medial and deepest
Biceps brachii - most superficial
Brachialis - deep to biceps and more distal