Fundamentals: Anatomy - Fascial compartments, bursae and potential spaces

Question 1

What is the superficial fascia?

Answer 1

Subcutaneous tissue

Question 2

What is the deep fascia composed of?

Answer 2

Dense connective tissue (does not contain fat unlike superficial fascia)

Devoid of fat

Question 3

Outline 5 different extensions and modifications of the deep fascia and their roles

Answer 3

1. Epimysium: invests individual muscles
2. Investing fascia: surrounds neurovascular bundles
3. Intermuscular septa: divide muscles into groups/compartments (also surrounded by fascia to form fascial compartments of muscles with similar functions)
4. Subserous fascia (does contain fat): lies between musculoskeletal walls and the serous membranes lining body cavities (e.g. endothoracic, endoabdominal, endopelvic)
5. Retinacula (markedly thickened): hold tendons in place during joint movements

Question 4

What happens to deep fascia when it meets bone?

Answer 4

Blends firmly with the periosteum

Question 5

Explain the role of the deep fascia in the musculovenous pump

Answer 5

1. Unyielding deep fascia limits outward expansion of the bellies of contracting skeletal muscles
2. Results in compression of the veins of the muscles/compartments, which causes blood to be pushed out back toward the heart
3. Venous valves prevent backflow as muscles relax

Question 6

Give 3 examples of subserous fascia

Answer 6

Endothoracic
Endoabdominal
Endopelvic
(Endoabdominal and endopelvic collectively can be referred to as extraperitoneal fascia)

Question 7

Define bursae

Answer 7

Closed sacs or envelopes of serous membrane (delicate connective tissue membrane capable of secreting fluid to lubricate a smooth internal surface)
Normally collapsed as potential spaces

Question 8

What is the role of bursae?

Answer 8

To enable free movement of one structure over another

Question 9

What are mesenteries

Answer 9

Transitional folds of synovial membrane between the continuous parietal and visceral layers surrounding the connecting stalks and/or neurovascular structures serving the surrounded mass

Question 10

What is a mesotendon?

Answer 10

Mesentery in a synovial tendon sheath

Question 11

Describe 4 types of bursae

Answer 11

1. Subcutaneous bursae: occur in subcutaneous tissue between the skin and bony prominences (e.g. at the elbow or knee)
2. Subfascial bursae: lie beneath deep fascia
3. Subtendinous bursae: facilitate movement of tendons over bone
4. Synovial tendon sheaths: specialised type of elongated bursae that wrap around tendons, usually enclosing them as they traverse osseofibrous tunnels that anchor the tendons in place

Question 12

What are fascial planes and what are their clinical relevance?

Answer 12

Potential spaces between adjacent fascias or fascia-lined structures or within loose areolar fascias, such as the subserous fascias
Used by surgeons to separate structures to create spaces that allow movement and enable access to deeply placed structures
Vessels may course along these planes but do not pierce them (vessels and nerves only pierce fixed fascia)