Fascial Compartments & Venous Drainage Flashcards
What is necrotizing fasciitis?
A lethal bacterial infection that destroys fascia.
How many spaces are there in the head and neck region?
16.
List the subtypes of spaces in the head and neck region.
- Fasical spaces of the face (5).
- Suprahyoid fascial spaces (5).
- Infrahyoid fascial spaces (1).
- Fascial spaces of the neck (5).
List 2 functions of fascial compartmentalisation.
1 - Ease of movement.
2 - Determine spread of infection.
List the tissue layers of the neck from superficial to deep.
1 - Skin.
2 - Subcutaneous fat.
3 - Superficial fascia.
4 - Platysma muscle.
5 - Deep cervical fascia.
List the types of deep cervical fascia in the neck.
1 - Investing fascia.
2 - Pretracheal fascia.
3 - Prevertebral fascia.
4 - Carotid sheaths and alar fascia.
Which layers of fascia condense to form carotid sheath?
The prevertebral, pretracheal and investing fascia.
List the structures that the investing layer of deep fascia encloses in the neck.
1 - Trapezius.
2 - Sternocleidomastoid.
3 - Submandibular gland.
Where is the pretracheal layer of deep fascia?
From the hyoid bone into the thorax, where it blends with the pericardium.
List the structures that the pretracheal layer of deep fascia encloses in the neck.
1 - Infrahyoid muscles.
2 - Trachea.
3 - Oesophagus.
4 - Thyroid.
Where is the prevertebral layer of deep fascia?
It attaches superiorly to the cranial base and inferiorly to the endothoracic fascia.
What is the axillary sheath?
A fibrous sheath that encloses the axillary artery and the three cords of the brachial plexus to form the neurovascular bundle.
What is the retropharyngeal space and where is it?
It is a potential space between the prevertebral fascia and the pretracheal fascia.
Where is the alar fascia?
- Part of the prevertebral fascia.
- Originates from the first cervical vertebra and reaches the second cervical vertebra.
Which structure separates the retropharyngeal space?
What are the subsequent divisions of the retropharyngeal space?
- Alar fascia.
- The space is divided into an anterior / true retropharyngeal space and a posterior / danger retropharyngeal space.
What might create potential spaces in the head?
- Pus from infections.
- Blood from perforated vessels.
Where is the retropharyngeal space?
- Anterior to the prevertebral muscles and prevertebral fascia.
- Posterior to the pharynx, oesophagus and buccopharyngeal fascia.
- Bounded laterally by carotid sheath.
Where is the parapharyngeal space?
- Anterior to the prevertebral layer of deep fascia.
- Posterior to the investing layer of deep fascia covering the pterygoid muscle.
- Bounded laterally by the investing layer of deep fascia covering the parotid gland.
List the tissue layers of the thigh from superficial to deep.
1 - Skin.
2 - Superficial fascia.
3 - Deep fascia.
4 - Medial intermuscular septum.
5 - Lateral intermuscular septum.
6 - Posterior intermuscular septum.
List the compartments of the thigh.
- Anterior compartment.
- Medial compartment.
- Posterior compartment.
Which artery is the source of the common blood supply to all compartments of the thigh?
Profunda femoris.
List the functions of the muscles of the thigh by compartment.
- Anterior: Knee extensors and hip flexors.
- Posterior: Knee flexors and hip extensors.
Medial: Hip adductors.
List the muscles of the anterior compartment of the thigh.
- Quadriceps:
1 - Rectus femoris.
2 - Vastus medialis.
3 - Vastus lateralis.
4 - Vastus intermedius.
List the muscles of the posterior compartment of the thigh.
- Hamstrings:
1 - Semimembranosus.
2 - Semitendinosus.
3 - Biceps femoris.
List the muscles of the medial compartment of the thigh.
- Hip adductors:
1 - Gracilis.
2 - Obturator externus.
3 - Adductor brevis.
4 - Adductor longus.
5 - Adductor magnus.
List the compartments of the leg.
- Anterior compartment.
- Lateral compartment.
- Posterior compartment.
Describe the innervation of the anterior compartment of the thigh.
- Supplied by the femoral nerve.
- Roots L2-4.
Describe the innervation of the medial compartment of the thigh.
- Supplied by the obturator nerve.
- Roots L2-4.
Describe the innervation of the posterior compartment of the thigh.
- Supplied by the sciatic nerve.
- Roots L4-S3.
Describe the blood supply to the anterior compartment of the thigh.
Supplied by the femoral artery.
Describe the blood supply to the medial compartment of the thigh.
Supplied by the obturator artery.
Describe the blood supply to the posterior compartment of the thigh.
Supplied by perforating branches of profunda femoris.
Which structures separate the leg into its compartments?
- Fascia.
- The interosseus membrane between the tibia and fibula.
What are the muscle groups contained within the posterior compartment of the leg?
What do these groups form?
- Superficial and deep groups.
- Both groups form the calf muscles.
List the superficial muscles of the posterior compartment of the leg.
- Triceps surae:
1 - Gastrocnemius.
2 - Soleus.
3 - Plantaris.
What is the common tendon of insertion of the superficial muscles of the posterior compartment of the leg?
Where does this tendon insert?
- The tendo calcaneous / achilles tendon.
- This tendon inserts into the calcaneus of the foot.
What is the function of the superficial muscles of the posterior compartment of the leg?
Plantarflexion.
List the deep muscles of the posterior compartment of the leg.
1 - Popliteus.
2 - Flexor halucis longus.
3 - Tibialis posterior.
4 - Flexor digitorum longus.
Which of the deep muscles of the posterior compartment of the leg act on the knee joint?
Which joint do the other muscles act on?
- Popliteus acts on the knee joint.
- The other 3 act on the ankle and foot joints.
List the muscles of the lateral compartment of the leg.
1 - Fibularis longus.
2 - Fibularis brevis.
List the muscles of the anterior compartment of the leg.
1 - Tibialis anterior.
2 - Extensor digitorum longus.
3 - Extensor hallucis longus.
4 - Fibularis tertius.
What is the function of the muscles of the lateral compartment of the leg?
Eversion of the foot.
What is the function of the muscles of the anterior compartment of the leg?
Dorsiflexion of the foot.
List the structures of the venous tree from start to finish.
1 - Post-capillary venules.
- Small veins.
- Large veins.
- Vena cava entering the right atrium.
Why does venous blood tend to pool in the lower extremities?
Gravitational pull. This is facilitated by the low pressure of the system.
How do veins benefit from thin walls?
The thin walls allow the veins to easily collapse, passively pumping blood.
List 3 types of veins.
1 - Superficial veins.
2 - Perforating veins (connect superficial veins to deep veins).
3 - Deep veins.
4 - Accompanying veins:
- Vaso vasorum (supply the walls of large veins).
- Venae commitante (supply the walls of large arteries.
What is the musculovenous pump?
The contraction of muscles and the subsequent pressure applied to the veins embedded in them that aids the flow of venous blood to the heart.
Which direction does venous blood flow through perforating veins?
From superficial veins to deep veins.
When does compartment syndrome occur?
When perfusion pressure falls below tissue pressure (i.e. when compartment pressure is too high).
List 2 causes of compartment syndrome.
1 - Decreased compartment size.
2 - Increased fluid content.
List 5 causes of increased fluid content in an anatomical compartment.
1 - Burns.
2 - Intra-arterial injection.
3 - Infiltrated infusion.
4 - Haemorrhages.
5 - Venom.
Why does compartment syndrome follow the path of ischaemic injury?
- The increased intracompartmental pressure decreases tissue perfusion until no oxygen is available for cellular metabolism.
- Hence compartment syndrome follows the path of ischaemic injury.
What is the carotid sheath?
The fibrous connective tissue that surrounds the vascular compartment of the neck.
In which compartment of the thigh is the pectineus muscle?
It can be classified in the medial compartment of thigh (when the function is emphasized) or the anterior compartment of thigh (when the nerve is emphasized).
