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Question 1

The clavicle is the only bony attachment between the upper limb and trunk. Because it is involved with transferring forces from the upper limb to the trunk, it can easily be fractured.

The scapula is part of the shoulder girdle and all girdles plus limbs are part of the appendicular skeleton. The clavicle is the only bone that connects the upper limb to the trunk.

Which part of the clavicle is usually fractured and why

State the grooves and impressions in the inferior part of the clavicle

Answer 1

The clavicle is usually fractured medial to the conoid tubercle because the middle third of the bone is not reinforced with ligaments or muscles.
• The anterosuperior surface of the clavicle is palpable along its lengt

Excellent observation — you’re absolutely right to ask about the subclavian groove and its relation to the middle third of the clavicle!

Let’s break it down:

1. Clavicle fracture site:
   • The most common site of clavicle fracture is the middle third — around the junction of the medial two-thirds and lateral one-third.
   • This area is thin and curved, and it lacks strong muscular or ligamentous support, making it mechanically weaker.
   • That’s why fractures often occur just medial to the conoid tubercle (which is on the lateral third).
2. Subclavian groove:
   • Yes, the subclavian groove is located on the inferior surface of the middle third of the clavicle.
   • It provides attachment for the subclavius muscle and the clavipectoral fascia.

So why is it still a weak point despite the subclavian groove?

Even though the subclavius muscle attaches there, it’s a small muscle and doesn’t offer the same strong support as the ligaments attached laterally (like the conoid and trapezoid ligaments of the coracoclavicular ligament complex).

In summary:
• The subclavian groove is in the middle third, yes.
• But this middle third is still the weakest structurally, because:
• It’s more slender and curved.
• It lacks the strong ligaments that reinforce the lateral third.
• The subclavius muscle isn’t strong enough to significantly reinforce it.

That’s why fractures usually happen around that region, even though there’s a groove and a muscle attachment there.

They’re the trapezius line, conoid tubercle(lateral 1/3rd along with the trapezius line), subclavian groove(middle 1/3rd), impression for the costoclavicular ligament(medial 1/3rd( (from most lateral to the medial part)

The coracoclavicular (CC) joint is a synovial joint between the clavicle and the coracoid process of the scapula. The costoclavicular (CC) joint is a synovial joint between the clavicle and the first rib

The trapezoid and conoid ligament come together to form the coracoclavicular ligament. The trapezoid ligament and conoid ligament come together to form the:

Coracoclavicular ligament

This is a strong pair of ligaments that connect the clavicle to the coracoid process of the scapula, and they work together to:
• Stabilize the acromioclavicular (AC) joint
• Suspend the scapula and upper limb from the clavicle

Breakdown:
• Trapezoid ligament = more lateral and runs almost horizontally.
• Conoid ligament = more medial and runs more vertically.

Together, they prevent the clavicle from being pulled upward and help maintain shoulder alignment.

So in short:
• Impression near medial end = Costoclavicular ligament
• Conoid tubercle & trapezoid line near lateral end = Coracoclavicular ligament (conoid + trapezoid parts)

Question 2

Where do the SITS muscles of the rotator cuff insert at, where do they originate from?

Answer 2

The SIT muscles (Supraspinatus, Infraspinatus, and Teres minor) insert on the greater tubercle of the humerus, not originate from it.

Breakdown:
• Supraspinatus inserts on the superior facet of the greater tubercle.
• Infraspinatus inserts on the middle facet.
• Teres minor inserts on the inferior facet.

These muscles originate from the scapula, and their insertion on the greater tubercle helps stabilize the shoulder joint and assist in arm movements.

(They’re part of the rotator cuff, along with subscapularis, which inserts on the lesser tubercle.)

Great! Let’s look at the specific origins of the SIT muscles (Supraspinatus, Infraspinatus, Teres Minor), which are part of the rotator cuff:

1. Supraspinatus
   • Origin: Supraspinous fossa of the scapula (the shallow depression above the spine of the scapula)
   • Insertion: Superior facet of the greater tubercle of the humerus
2. Infraspinatus
   • Origin: Infraspinous fossa of the scapula (the large surface below the spine of the scapula)
   • Insertion: Middle facet of the greater tubercle
3. Teres Minor
   • Origin: Lateral border of the scapula, specifically the upper two-thirds of the posterior surface
   • Insertion: Inferior facet of the greater tubercle

So:
• All originate from specific parts of the scapula
• All insert on different facets of the greater tubercle

Let me know if you want a quick mnemonic to remember this!

Question 3

The three most common sites of humeral fracture are

Answer 3

Surgical neck
Midshaft
Supracondylar

Question 4

Sure! Here are short answer questions that cover everything in the response above:

1.	What is the suprascapular notch?
2.	Where is the suprascapular notch located?
3.	Which ligament bridges the suprascapular notch?
4.	What does the suprascapular notch become when bridged by the transverse scapular ligament?
5.	What structure passes under the transverse scapular ligament?
6.	Which structures usually pass over the transverse scapular ligament?
7.	What mnemonic helps remember the relationship of the artery and nerve at the suprascapular notch?
8.	What is the name of the foramen formed when the suprascapular notch is bridged by a ligament?
9.	If the transverse scapular ligament is absent, what does the area remain as?
10.	Is the suprascapular notch the same as the supraclavicular notch? Why or why not?

Let me know if you want the answers filled in too!

Answer 4

You’re very close — let’s clarify and rephrase it for better understanding:

Correct Concept:
• The suprascapular notch is a notch on the superior border of the scapula, near the base of the coracoid process.
• It is bridged by the transverse scapular ligament (also called the superior transverse scapular ligament).

When the ligament is present:
• It converts the notch into a foramen called the:
• Suprascapular foramen (not “foramen scapular”).
• Through this foramen:
• The suprascapular nerve passes under the ligament (through the foramen).
• The suprascapular artery and vein usually pass over the ligament (not through the foramen).
• Mnemonic: “Army over Navy under” (A=artery, N=nerve)

If the ligament is absent:
• The notch remains a simple suprascapular notch — not called supraclavicular notch (which is a different anatomical structure in the clavicle).

To summarize:
• Ligament present: Suprascapular notch → Suprascapular foramen
• Ligament absent: Remains the suprascapular notch
• Suprascapular nerve goes through the foramen (under the ligament)

Let me know if you want a labeled diagram to visualize this!

Great! Here are the short answer questions with their answers:

1.	What is the suprascapular notch? – A notch on the superior border of the scapula.
2.	Where is the suprascapular notch located? – Near the base of the coracoid process on the scapula.
3.	Which ligament bridges the suprascapular notch? – The transverse scapular ligament (superior transverse scapular ligament).
4.	What does the suprascapular notch become when bridged by the transverse scapular ligament? – The suprascapular foramen.
5.	What structure passes under the transverse scapular ligament? – The suprascapular nerve.
6.	Which structures usually pass over the transverse scapular ligament? – The suprascapular artery and vein.
7.	What mnemonic helps remember the relationship of the artery and nerve at the suprascapular notch? – “Army over Navy under” (Artery over, Nerve under the ligament).
8.	What is the name of the foramen formed when the suprascapular notch is bridged by a ligament? – Suprascapular foramen.
9.	If the transverse scapular ligament is absent, what does the area remain as? – It remains the suprascapular notch.
10.	Is the suprascapular notch the same as the supraclavicular notch? Why or why not? – No. The suprascapular notch is on the scapula, while the supraclavicular notch is on the clavicle near the sternum.

Question 5

The sternoclavicular joint is reinforced by four ligaments
Name them
The acromioclavicuoar joint is reinforced by two ligaments. Name them

Rotator cuff muscles stabilize the glenohumeral joint so it doesn’t have ligaments that reinforce it

The lateral angle not the lateral border of the scapula is modified to form the glénoïd cavity

Answer 5

Sterno: anterior and posterior strernoclavicular ligaments, costoclavicular ligament(this just connects the proximal end of the clavicle to the first rib) ,interclavicular ligament
Acromio: small acromioclaviucoar ligament and big coracoclavicular ligament. and acror and
• a much larger
cacoclavicularligament, which is
not directly related to the join
is an important
strong accessory ligament, providing much of the weight-bearing support for the upper limb on the clavicle and maintaining the position of the clavicle on the acromion-it spans the distance between the coracoid process of the scapula and the inferior surface of the acromial end of the clavicle

Glenohumeral joint

Question 6

Between Which joints in the elbow joint are involved in the hinge like extension and flexion of the forearm on the arm and between which joints in the elbow joint are invovled in the pronation and supination of the forearm

Answer 6

Extension flexion:
Between the Head of the radius and the capitulum of the humerus and between the Trochlear notch of the ulna and the Trochlear of the humerus

Pronation and supination:
Joint Between the Head of the radius and the radial notch on the ulnar, the proximal radio-ulnar joint

Question 7

State the three parts of axillary artery and the number of branches each part had

Answer 7

The axillary artery has 3 parts, divided by the pectoralis minor muscle:

Part,Location,Branches

First part,Before (proximal to) pectoralis minor,1 branch → Superior thoracic artery
Second part,Behind (deep to) pectoralis minor,2 branches → Thoracoacromial artery and Lateral thoracic artery
Third part,After (distal to) pectoralis minor,3 branches → Subscapular artery, Anterior circumflex humeral artery, Posterior circumflex humeral artery

Easy way to remember:
• 1st part → 1 branch
• 2nd part → 2 branches
• 3rd part → 3 branches

Mnemonic for branches:
“Screw The Lawyer Save A Patient”
(Superior thoracic, Thoracoacromial, Lateral thoracic, Subscapular, Anterior circumflex humeral, Posterior circumflex humeral)

Question 8

The 5 Groups of the axillary lymph nodes

Answer 8

The axillary lymph nodes are divided into 5 groups, based on their location around the axillary (armpit) area:
1. Central nodes – Located in the center of the axilla.
2. Pectoral (anterior) nodes – Located along the lower border of the pectoralis major muscle.
3. Subscapular (posterior) nodes – Located along the subscapular artery, near the scapula.
4. Lateral nodes – Located along the humerus, near the axillary vein.
5. Apical nodes – Located at the apex of the axilla, near the clavicle and first rib.

Quick way to remember:

“Please Send Little Packages Away” (For Pectoral, Subscapular, Lateral, Pectoral, Apical)

Note: The axillary nodes are important for draining the upper limb and chest, and they can be affected in conditions like breast cancer.

Would you like a reminder on how to check for lymph node enlargement?