Anterior and Lateral compartments of the leg Flashcards
Compartment syndrome:
- What is it
- Why does it cause loss of limb?
Increase in pressure inside a muscle or compartment which restricts blood flow and causes pain
muscles become ischaemic
How many fascial components of the leg
Anterior, lateral and
posterior
Purpose of deep fascia
Deep Fascia –encases contents including bone where subcutaneous
Whats included in the anterior, posterior, medial and lateral compartments
Anterior
Deep (crural) fascia and skin
Posterior
Interosseus membrane
Medial
Lateral surface of tibia
Lateral
Anterior intermuscular septum
Anteropr compartment muscles, artery and nerve
-Forms what compartment
4 Muscles:
Tibialis anterior
Extensor digitorum longus (EDL)
Extensor hallucis longus (EHL)
Peroneus tertius
1 artery (and vein)
Anterior tibial
1 Nerve
Deep peroneal nerve
It is the dorsiflexor compartment
Interosseus membrane
- purpose in leg
Interosseusmembraneconnects the tibia and fibular the entire lengths of the bones
Label bones of the leg anatomy and Xray
Lecture Slide
Anterior Compartment Muscle origins, insertion, action and nerve supply
Tibialis Anterior
Origin:
Superior 1/2 of lateral tibia and IM
Insertion:
Medial cuneiform and base of first MT
Action:
Dorsifelxion ankle, invert foot at subtalar joint
Nerve:
Deep peroneal
Extensor Digitorum Longus:
Origin:
Lateral condyle of tibia, Superior 3/4 of medial fibila and IM
Insertion:
Middle and distal phalanges of lateral 4 toes
Action:
Dorsifelxion ankle, Extends toes
Nerve:
Deep Peroneal
Extensor Halicus Longus:
Origin:
Middle anterior Fib and IM
Insertion:
Base of distal Phalanx of great toe
Action:
Dorsiflexon of ankle
Extend great toe
Nerve:
Deep peroneal
Peroneus Tertius:
Origin:
Inferior 1/3 anterior fib and IM
Insertion:
Base of 5th MT
Action:
Dorsiflexon of ankle, everts foots at subtalar joint
Nerve:
Deep peroneal
Axial of foot:
Medial attachment =
Lateral attachment =
Medial attachment = INVERSION
Lateral attachment = EVERSION
Lateral Compartment Muscles:
Origin
Insertion
Action
Nerve supply
Peroneus Longus:
Origin
Superior 2/3 of lateral fib
Insertion
Base of 1 mT and medial cuneiform
Action
Everts foot, weak plantarflexion
Nerve supply
Superificial peroneal
Peroneus Brevis
Origin:
Inferior 2/3 lateral fib
Insertion:
Base of 5 MT
Action
Everts foot, weak plantarflexion
Nerve supply
Superificial peroneal
Lateral compartment
how many muscles, nerves, artery
Two muscles
One nerve
No artery
Retinaculum:
what is it
Where is it
-purpose
thickening of the facia
Anterior aspect
stops tendons bowstringing when they shorten ,
holds them down
Types of retinaculum
Superior extensor and Inferior extensor
Describe superior Extensor Retinaculum
type of fascia
-passes from/to
-binds down… to prevent…
-where does the inferior retinaculum bind to?
Is a band of deep fascia. It passes from the tibia to the fibula, above the malleoli.
It binds down the tendons of Extensor, digitorum Longus, Extensor Hallucis Longus, Peroneus Tertius and Tibialis Anterior, preventing them from bowstringing during dorsiflexion
Inferior: Binds at base of tibula to other side of bone of foot and then back to tibia side
Describe Inferior Extensor Retinaculum
-shape/type of fascia
-attachment sittes
is a Y- shaped band of deep fascia. The lateral attachment is to the upper surface of the calcaneus; the medial side attaches to medial malleolus (proximally) and the plantar aponeurosis (distally).
Draw on diagram where the Superior extensor and inferior extensor retinaculum are
Lecture Slide
What tendons does the superior and inferior peroneal retinacula contain (This is on lateral side of foot)
-Label on diagram
tendons of the Peronus longus and brevis laterally.
Nerves of posterior leg
- Sciatic Nerve (L4-S3)
-divides in the posterior thigh to its two terminal branches (Tibial nerve and common peroneal nerve)
-Exits from pelvis via greater sciatic foramen
-lies posterior aspect of adductor magnus - Common peroneal nerve
-exits the popliteal fossa laterally and winds around the neck of the fibula where it divides into the deep and superifical peroneal nerves
Describe the deep vs superficial peroneal nerve
- nerve supplys where
- supplies what muscles
The Deep Peroneal nerve is the nerve to the anterior compartment, where it travels with the Anterior Tibial artery.
It crosses the ankle joint, supplies the muscles of the dorsum of the foot, and
then becomes cutaneous to the first webspace
The Superficial Peroneal nerve enters the lateral compartment and supplies both the muscles in this compartment.
This nerve then continues as a cutaneous nerve, supplying the skin of the anterior leg and most of the dorsum of foot
Cutaneous Innervation of the leg is by…
are terminal branches of the Lumbosacral Plexus.
- Saphenous nerve (from the Femoral nerve)
- Superficial and Deep Peroneal nerves (from the Sciatic nerve)
- Sural nerve (from the Tibial and Common Peroneal nerves)
- Medial and Lateral Plantar nerves (from the Tibial nerve).
Label all the nerve supply on leg
-obtruator nerve
Femoral nerve (anterior cutaneous nerve of thigh)
Femoral nerve (Saphenous nerve)
Common fibular nerve (deep branch)
Medial plantar nerve
Lateral plantar nerve
Tibial Nerve
Common fibular nerve (Superifical branch)
Common fibular nerve (lateral cutaneous of calf)
Tibial nerve (medial calcaneal branches)
Posterior rami (L1-L3 AND S1-S3)
Colourful lecture Slide
Cutaneous Innervation of the leg
-label diagram
Lecture Slide
- Subcostal
-Lateral femoral cutaneous - Intermediate femoral cutaneous
- LAteral sural
- Superifical peroneal
-Sural
-Saphenous
-Medial femoral cutaneous
-Cutaneous branch of obutrator
LLio-ingiunal
-femoral branch of gentiofermoral
Arterial branches to the knee
- when does femoral artery becomes popliteal artery
-where does the popliteal nerve branch to
The Femoral artery becomes the Popliteal artery as it enters the superior aspect of the Popliteal Fossa.
Branches to the knee from descending branch of lateral circumflex femoral artery, femoral artery, anterior tibial
artery
Label arterys on leg
Lecture Slide
The Anterior Tibial artery passes ____ through a gap in the ______to become the artery to the ____compartment
The Anterior Tibial artery passes anteriorly through a gap in the Interosseus membrane to become the artery to the anterior compartment
How does the anterior tibial artery pass through ankle joint
At the ankle joint it crosses midway between the malleoli, between the tendons of EDL and EHL, to become the Dorsalis Pedis artery (artery to the dorsum of the foot).
What forms the deep plantar acrh
The Dorsalis Pedis gives off a branch called the Deep Plantar artery, which passes between the 1st and 2nd metatarsals to form part of the Deep Plantar Arch.
Arteries of the Leg and Dorsal Foot
-describe the flow of the politeal artery: start from politeal artey after it gives off to the anterior tibial artery
After giving off the Anterior Tibial artery, the Popliteal artery continues as the Posterior Tibial artery
This bifurcates to give off the Peroneal artery.
The Posterior Tibial artery travels through the deep posterior compartment, accompanied by the Tibial nerve and veins, eventually running posterior to the medial maellolous. After this point the artery dvides into its two terminal branches, the medial and lateral plantar arteries to the sole of the foot.
Describe flow of Peroneal artery
The Peroneal artery runs laterally towards the fibula (still within the deep posterior compartment) giving perforating branches to the muscles
Dorsum of foot contents:
How many/what nerves
How many arteries
3 nerves:
Deep peroneal
Superifical Peroneal
Saphenous (Medial from femoral nerve)
1 artery
Clinical applications:
Compartment Syndrome
It most often occurs in the leg or forearm following trauma.
It occurs when the pressure inside a compartment is raised to the point that there is no longer an arterial supply to the compartment, putting muscles and eventually nerves at risk of ischemia and necrosis
Clinical findings are: pain, pallor, pulselessness, paraestheesia and paraylsis
Foot drop
- what is it
-when does it happen
- changes to foot axis
-causes what types of gait
-causes
Weakness of anterior compartment muscles (dorsiflexion)
Occurs when common peroneal, or deep peroneal nerves are injured.
The passive position of the foot is plantar flexed and inverted
Results in high stepping or slapping gait as dorsiflexors of the ankle are not functioning.
Causes:
Deep Peroneal Nerve Sciatic Nerve
L4/5
