Anterior & Lateral Leg Flashcards
The Crural Fascia is the deep fascia of the leg and continuous with the _______ _______. It covers the leg muscles and is part of the proximal attachment of underlying muscles. It thickens distally to form the ________ _________.
Fascia Lata
Extensor Retinaculum
This septum separates the anterior leg compartment from the lateral leg compartment.
Anterior septum
This septum separates the lateral leg compartment from the posterior (superficial) leg compartment.
Posterior septum
What separates the anterior leg compartment from the posterior (deep) compartment?
Interosseous membrane
What are the muscles within the anterior leg compartment?
Tibialis Anterior M.
Extensor Hallucis Longus M.
Extensor Digitorum Longus M.
Fibularis Tertius M.
What are the primary function of the anterior leg compartment?
Dorsiflexion
Toe extension
This is the a long, thick muscle on the anterolateral surface of the Tibia. It attaches proximally to the lateral tibial condyle and distally to the medial side of first cuneiform and first metatarsal.
Tibialis Anterior M.
What are the functions of the Tibialis Anterior M.?
Dorsiflexion
Inversion
The Extensor Digitorum Longus M. attaches proximally to the lateral tibial condyle, anterior fibula, and interosseous membrane. How does it attach distally?
Four tendons create extensor expansions over lateral four digits.
Two lateral slips – go to distal phalanx
One central slip – go to middle phalanx
What are the functions of the Extensor Digitorum Longus M.?
Extends lateral four digits
Dorsiflexion
This muscle fuses with the Extensor Digitorum Longus M. proximally and its tendon does NOT attach to a digit. Sometimes absent.
Fibularis Tertius M.
***DO NOT confuse this muscle with other “fibularis” muscles – those are in lateral compartment
This muscle attaches proximally to the anteroinferior fibula and distally to the dorsum of the fifth metatarsal.
Fibularis Tertius M.
What functions does the Fibularis Tertius M. perform?
Dorsiflexion
Eversion
This muscle is lateral to the Tibialis Anterior M. and attaches proximally to the anteromedial fibula and interosseous membrane. Distally attaches to the base of distal phalanx of hallux.
Extensor Hallucis Longus M.
***Runs medial to Extensor Digitorum Longus M. – more central in the foot
This nerve supplies all muscles of the anterior leg compartment.
Deep Fibular N.
The Deep Fibular N. runs inferomedially with the _______ _______ vessels between the Tibialis Anterior M. and the Extensor Hallucis Longus M.
Anterior Tibial (A. and V.)
Where does the Deep Fibular N. provide cutaneous innervation?
Skin between the first and second digit
This artery arises from the Popliteal A. and supplies blood to the anterior leg compartment.
Anterior Tibial A.
What demarcates the approximate point of the division of the Anterior and Posterior Tibial As.?
Tibial Tuberosity
The Anterior Tibial A. passes anteriorly over the Interosseous Membrane with the Deep Fibular N., between which muscles?
Extensor Hallucis Longus M.
Tibialis Anterior M.
Where does the Anterior Tibial A. terminate?
At ankle between malleoli to become Dorsalis Pedis A.
What muscles are in the lateral leg compartment?
Fibularis Brevis M.
Fibularis Longus M.
This is a list of over 7,500 internationally accepted terms for anatomical structures decided by the Federation of Associations of Anatomists (FIAA).
Terminologia Anatomica
This muscle extends form the fibular head to the sole of the foot and is superficial to Fibularis Brevis M.
Fibularis Longus M.
The Fibularis Longus M. attaches proximally to the fibular head, then passes inferior just posterior to the ________ _______ and attaches distally across the sole of the foot to the _______ _______ and _______ _______.
Lateral Malleolus
First Metatarsal
Medial Cuneiform
What are the functions of the Fibularis Longus M.?
Eversion
Plantar flexion
This is a component of the Calcaneus that separates the tendons of Fibularis Longus M. and Fibularis Brevis M.
Fibular Trochlea
***Ridge on lateral surface of Calcaneus
This tarsal bone is the most lateral and contains a groove for the Fibularis Longus M.
Cuboid
What is the name for the groove on the Cuboid for the Fibularis Longus M.?
Cuboid sulcus
This bone articulates with the Calcaneus posteriorly, 4th and 5th metatarsals anteriorly, and Navicular and Lateral Cuneiform medially.
Cuboid
This muscle is deep to Fibularis Longus M.
Fibularis Brevis M.
The proximal attachment for the Fibularis Brevis M. is the inferolateral Tibia, then it descends posterior to the _______ _______ and attaches distally to the dorsal surface of the lateral tuberosity of the ________ ________.
Lateral Malleolus
Fifth Metatarsal
What are the functions of the Fibularis Brevis M.?
Eversion
Plantar flexion
***Same as Fibularis Longus M.
This branch of the Common Fibular N. begins between the Fibularis Longus M. and the Fibula.
Superficial Fibular N.
What does the Deep Fibular N. innervate?
Anterior leg compartment Ankle joint Metacarpal phalangeal joints Dorsal intrinsic foot muscles Skin b/w first and second digits
The Superficial Fibular N. descends between Fibularis Longus and Brevis Ms. then runs lateral to which muscle?
Extensor Digitorum Longus M.
What does the Superficial Fibular N. innervate?
Lateral leg compartment
Anteroinferior leg (cutaneous)
Dorsal surface of foot (cutaneous)
Dorsal aspect of digits (cutaneous)
***Except between digits 1 and 2 – these have cutaneous innervation via Deep Fibular N.
Why is the Common Fibular N. the most commonly injured LE nerve?
Because it winds superficially around the fibular head
What does injury to the Common Fibular N. result in?
Paralysis of all anterior and lateral leg compartment muscles – results in foot drop from loss of dorsiflexion and eversion
If a patient presents with a high-stepping gait, and they swing their leg strongly forward with their foot striking the ground with a “clop”, what is the diagnosis?
Injury to Common Fibular N.
Patient is experiencing foot drop
If there is an injury to the Common Fibular N., where would there be loss of sensation?
Anterolateral leg
Dorsum of foot
What provides arterial supply to the lateral leg compartment?
Branches passing anteriorly from the Fibular A.
***Only compartment without a distinct arterial branch traveling the compartment nerve (Superficial Fibular N.)
This artery is the largest branch of the Posterior Tibial A.
Fibular A.
Leg compartmental syndromes occur due the septa being very tough and trauma causing hemorrhage, edema, and inflammation. The intracompartmental pressure may lead to ischemia and permanent injury. What is a way to relieve pressure for this?
Fasciotomy – incising fascia to relieve pressure within the compartment
This is caused by repetitive micro trauma to the Tibialis Anterior M. It induces small tears to the periosteum over the Tibia and to the overlying deep fascia.
Shin splints
Shin splints are considered a mild form of compartmental syndrome due to the swelling of the ________ ________ from repetitive ground reaction force.
Tibialis Anterior M.
