Clavipectoral Fascia

ANATOMY AIIMS, GROSS ANATOMY, EMBRYOLOGY, NEUROANATOMY, MICROANATOMY, APPLIED/ CLINICAL ANATOMY The clavipectoral fascia is a layer of connective tissue located in the upper chest region, which plays an important role in providing support and stability to the shoulder girdle. It is a complex structure that is composed of several layers of fascia, including the clavipectoral fascia proper, the costocoracoid membrane, and the coracoclavicular ligament.

The clavipectoral fascia proper is the most superficial layer of the clavipectoral fascia and extends from the clavicle to the pectoralis major muscle. It is a dense, fibrous layer that helps to anchor the pectoralis major muscle to the clavicle and provides a protective covering for the axillary vessels and nerves.

The costocoracoid membrane is a thin, fibrous layer of the clavipectoral fascia that extends from the first rib to the coracoid process of the scapula. It helps to stabilize the scapula and forms a protective tunnel for the subclavius muscle and the neurovascular structures that pass through it.

The coracoclavicular ligament is a strong, fibrous band that extends from the coracoid process to the inferior surface of the clavicle. It helps to support and stabilize the acromioclavicular joint and is an important structure in preventing dislocation of the clavicle.

The clavipectoral fascia is an important anatomical structure that is involved in several clinical conditions, including thoracic outlet syndrome, breast cancer, and axillary lymph node dissection. Understanding the anatomy and function of the clavipectoral fascia is essential for clinicians in the diagnosis and treatment of these conditions.

Several structures pierce the clavipectoral fascia, including nerves, blood vessels, and muscles. The clavipectoral fascia provides a protective covering for these structures as they pass through the upper chest region.

The structures that pierce the clavipectoral fascia include:

Cephalic vein: The cephalic vein is a superficial vein that originates in the hand and forearm and passes through the upper arm to enter the shoulder region. It pierces the clavipectoral fascia and empties into the axillary vein.

Thoracoacromial artery: The thoracoacromial artery is a branch of the axillary artery that supplies blood to the pectoral region. It pierces the clavipectoral fascia and divides into several branches that supply the pectoralis major muscle and the overlying skin.

Lateral pectoral nerve: The lateral pectoral nerve is a branch of the brachial plexus that supplies the pectoralis major muscle. It pierces the clavipectoral fascia and enters the muscle.

Clavipectoral lymphatics: The clavipectoral lymph nodes are a group of lymph nodes that drain lymph from the upper limb and the pectoral region. They pierce the clavipectoral fascia and are located between the clavicle and the pectoralis minor muscle.

References

Gray H. Anatomy of the Human Body. 20th edition. Philadelphia: Lea & Febiger; 1918. Available from: https://www.bartleby.com/107/

Standring S. Gray's Anatomy: The Anatomical Basis of Clinical Practice. 41st edition. Elsevier; 2016.

Tubbs RS, Salter EG, Oakes WJ. Surgical anatomy of the clavipectoral fascia and its relevance. Clin Anat. 2006 Jan;19(1):28-34. doi: 10.1002/ca.20181. PMID: 16331611.

Multiple Choice Questions on Clavicle

ANATOMY AIIMS, GROSS ANATOMY, EMBRYOLOGY, NEUROANATOMY, MICROANATOMY, APPLIED/ CLINICAL ANATOMY 1. The clavicle bone is also known as:

a) collar bone

b) shoulder blade

c) hip bone

d) thigh bone

Answer: a) collar bone

2. Which joint does the clavicle articulate in the shoulder region?

a) glenohumeral joint

b) acromioclavicular joint

c) sternoclavicular joint

d) scapulothoracic joint

Answer: b) acromioclavicular joint

3. What is the function of the clavicle?

a) to provide attachment for the muscles of the neck

b) to transmit forces from the upper extremity to the axial skeleton

c) to protect the spinal cord

d) to support the weight of the upper body

Answer: b) to transmit forces from the upper extremity to the axial skeleton

4. Which part of the clavicle is most fractured?

a) medial third

b) middle third

c) lateral third

d) distal end

Answer: b) middle third

5. Which nerve is at risk of injury when the clavicle is fractured?

a) radial nerve

b) median nerve

c) ulnar nerve

d) brachial plexus

Answer: d) brachial plexus

6. What is the treatment for a clavicle fracture?

a) immobilization with a sling

b) surgery with internal fixation

c) physical therapy

d) rest and pain medication

Answer: a) immobilization with a sling

7. Which of the following conditions can cause a deformity of the clavicle known as a "bump" or "knob"?

a) osteoporosis

b) osteoarthritis

c) rheumatoid arthritis

d) a healed clavicle fracture

Answer: d) a healed clavicle fracture

8. Which muscle attaches to the clavicle and is responsible for elevating the shoulder?

a) trapezius

b) latissimus dorsi

c) pectoralis major

d) serratus anterior

Answer: a) trapezius

9. What is the function of the clavicular notch on the sternum?

a) to articulate with the acromion process of the scapula

b) to attach the clavicle to the sternum

c) to provide a passage for blood vessels and nerves

d) to provide attachment for the pectoralis major muscle

Answer: b) to attach clavicle to sternum

10. How many muscles attach to the clavicle?

a) 5

b) 10

c) 15

d) 20

Answer: a) 5

11. Which ligament holds the clavicle in place at the sternoclavicular joint?

a) Coracoclavicular ligament

b) Acromioclavicular ligament

c) Sternoclavicular ligament

d) Interclavicular ligament

Answer: c) Sternoclavicular ligament

12. What is the function of the coracoclavicular ligament?

a) To attach the clavicle to the scapula

b) To attach the clavicle to the sternum

c) To support the weight of the upper body

d) To provide stability to the acromioclavicular joint

Answer: a) To attach the clavicle to the scapula

13. Which of the following is a common symptom of a clavicle fracture?

a) Swelling and bruising

b) Tingling and numbness in the arm

c) Difficulty breathing

d) Loss of balance

Answer: a) Swelling and bruising

14. Which bone is located immediately below the clavicle?

a) Humerus

b) Radius

c) Ulna

d) Scapula

Answer: d) Scapula

15. Which of the following is not a risk factor for clavicle fractures?

a) Age

b) Gender

c) Participation in contact sports

d) Osteoporosis

Answer: b) Gender

16. What is the medical term for a broken clavicle?

a) Clavicula fracture

b) Collarbone dislocation

c) Scapula injury

d) Clavicle sprain

Answer: a) Clavicula fracture

17. How long does it usually take for a clavicle fracture to heal?

a) 1-2 weeks

b) 4-6 weeks

c) 8-12 weeks

d) 16-20 weeks

Answer: c) 8-12 weeks

18. Which of the following is NOT a function of the clavicle?

a) Provides attachment for muscles

b) Transmits forces from the upper extremity to the axial skeleton

c) Protects the spinal cord

d) Helps to maintain shoulder stability

Answer: c) Protects the spinal cord

19. What is the most common cause of clavicle fractures?

a) Trauma

b) Osteoporosis

c) Repetitive strain

d) Infection

Answer: a) Trauma

20. What is the term for the deformity that can result from a clavicle fracture where the bone heals in a displaced position?

a) Malunion

b) Nonunion

c) Dislocation

d) Subluxation

Answer: a) Malunion

21. Which nerve runs along the underside of the clavicle and can be injured in a clavicle fracture?

a) Radial nerve

b) Median nerve

c) Ulnar nerve

d) Suprascapular nerve

Answer: d) Suprascapular nerve

22. Which ligament is commonly injured in acromioclavicular joint separations?

a) Coracoclavicular ligament

b) Acromioclavicular ligament

c) Sternoclavicular ligament

d) Interclavicular ligament

Answer: b) Acromioclavicular ligament

23. What is the medical term for a condition in which the clavicle is abnormally short or missing?

a) Clavicular hypoplasia

b) Clavicular aplasia

c) Clavicular dysplasia

d) Clavicular atrophy

Answer: b) Clavicular aplasia

24. What is the purpose of the interclavicular ligament?

a) To connect the clavicle to the scapula

b) To connect the two clavicles together

c) To provide stability to the sternoclavicular joint

d) To provide cushioning between the clavicle and other bones

Answer: b) To connect the two clavicles together

25. What is the name of the joint at the distal end of the clavicle?

a) Glenohumeral joint

b) Elbow joint

c) Wrist joint

d) Acromioclavicular joint

Answer: d) Acromioclavicular joint

26. What is the name of the condition where the clavicle fails to properly fuse during development, resulting in an extra piece of bone?

a) Clavicular dysplasia

b) Clavicular hypoplasia

c) Clavicular aplasia

d) Os acromiale

Answer: d) Os acromiale

27. Which of the following is a potential complication of a clavicle fracture?

a) Nerve damage

b) Arthritis

c) Chronic pain

d) All of the above

Answer: d) All of the above

28. Which muscle attaches to the clavicle and is responsible for rotating the arm laterally?

a) Deltoid

b) Pectoralis major

c) Trapezius

d) Latissimus dorsi

Answer: a) Deltoid

29. Which of the following statements about the clavicle is TRUE?

a) It is the only bone in the human body that does not articulate with any other bone.

b) It is the longest bone in the human body.

c) It is a bone that provides support for the shoulder girdle.

d) It is a long bone that is part of the axial skeleton.

Answer: c) It is a bone that provides support for the shoulder girdle.

30. What is the name of the joint at the proximal end of the clavicle?

a) Acromioclavicular joint

b) Sternoclavicular joint

c) Glenohumeral joint

d) Elbow joint

Answer: b) Sternoclavicular joint

31. Which of the following is NOT a function of the clavicle?

a) To transmit forces from the upper limb to the axial skeleton

b) To protect vital organs in the thoracic cavity

c) To provide an attachment site for muscles and ligaments

d) To provide support and stability for the shoulder girdle

Answer: b) To protect vital organs in the thoracic cavity

32. What is the name of the condition where the clavicle is abnormally short?

a) Clavicular hypoplasia

b) Clavicular dysplasia

c) Clavicular aplasia

d) There is no specific name for this condition

Answer: a) Clavicular hypoplasia

33. Which of the following is NOT a risk factor for clavicle fractures?

a) Participation in contact sports

b) Osteoporosis

c) Female gender

d) Motor vehicle accidents

Answer: c) Female gender

34. Which of the following is a potential complication of an acromioclavicular joint separation?

a) Impaired shoulder mobility

b) Chronic pain

c) Instability of the shoulder girdle

d) All of the above

Answer: d) All of the above

35. Which type of joint is the acromioclavicular joint?

a) Ball-and-socket joint

b) Hinge joint

c) Saddle joint

d) Plane joint

Answer: d) Plane joint

Poem on Clavicle

ANATOMY AIIMS, GROSS ANATOMY, EMBRYOLOGY, NEUROANATOMY, MICROANATOMY, APPLIED/ CLINICAL ANATOMY

From the acromial end to the sternal notch The clavicle bone, like a bridge, it does lodge With curves and contours, it links the chest and the shoulder A slender shaft that's both sturdy and bolder

Its rough undersurface and smooth upper part The clavicle bone, a study of art Attached to muscles that control our arms' sway Aiding in movements in every way

The subclavius muscle, it's the first to connect To the clavicle bone, from its medial aspect With contraction, it brings the clavicle down Assisting in movements, both up and down

The pectoralis major, a mighty one indeed Attaches to the clavicle, a vital need It helps move the arm towards the front of the chest With strength and grace, it's one of the best

The deltoid muscle, a shape so great The clavicle bone, it does integrate From the acromion process, it takes its place Its power and size, it cannot replace

The sternocleidomastoid, a muscle of the neck Attaches to the clavicle, with a firm bedeck It turns the head and flexes the neck Its movements so precise, with perfect check

The trapezius muscle, so broad and strong With fibers that attach, it doesn't belong It raises the scapula, with such ease The clavicle bone, it does please

From its medial to its lateral end The clavicle bone, a true friend Attached to muscles that aid in every way A vital part of the human array.