Leg and foot Flashcards
(116 cards)
What is the popliteal fossa and what is its role?
The popliteal fossa is a diamond shaped area located on the posterior aspect of the knee.
- It is the main path by which vessels and nerves pass between the thigh and the leg.
What are the borders of the popliteal fossa?
- Superomedial border – semimembranosus
- Superolateral border – biceps femoris
- Inferomedial border – medial head of the gastrocnemius
- Inferolateral border – lateral head of the gastrocnemius and plantaris
- The floor of the popliteal fossa is formed by the posterior surface of the knee joint capsule, popliteus muscle and posterior femur.
- The roof is made of up two layers: popliteal fascia and skin. The popliteal fascia is continuous with the fascia lata of the leg.
What are the contents of the popliteal fossa?
The popliteal fossa is the main conduit for neurovascular structures entering and leaving the leg. Its contents are (medial to lateral):
- Popliteal artery
- Popliteal vein
- Tibial nerve
- Common fibular nerve (common peroneal nerve)
What are the most superficial contents of the popliteal fossa?
Tibial and common fibular nerves (from the sciatic)
The common fibular nerve follows which route?
Follows the biceps femoris tendon, travelling along the lateral margin of the popliteal fossa
The small saphenous vein pierces the popliteal fossa and passes between the two heads of the gastrocnemius to empty into the…
Popliteal vein
What is the deepest structure in the popliteal fossa?
The popliteal artery
What is the tarsal tunnel and what is its role?
- The tarsal tunnel is a fibro-osseous space located on the posteromedial aspect of the ankle.
- It acts as a passageway for tendons, nerves and vessels to travel between the posterior leg and the foot.
What are the borders of the tarsal tunnel?
- The tarsal tunnel is formed by a bony floor and connective tissue roof.
- The floor is a concave surface formed by the medial aspect of the tibia, talus and calcaneus.
- It is converted into a tunnel by the flexor retinaculum, which spans obliquely between the medial malleolus and the medial tubercle of the calcaneus to form the roof. The flexor retinaculum is continuous with the deep fascia of the leg and foot.
What are the contents of the tarsal tunnel?
- The tarsal tunnel acts as a passageway for tendons, nerves and vessels to travel between the posterior leg and the foot. Its contents (anterior to posterior) are: • Tibialis posterior tendon • Flexor digitorum longus tendon • Posterior tibial artery and vein • Tibial nerve • Flexor hallucis longus tendon
• The mnemonic Tom, Dick and a Very Nervous Harry can be used to aid recall of these structures.
What is tarsal tunnel syndrome? Signs/symptoms and management?
It refers to the entrapment and compression of the tibial nerve as it passes through the tarsal tunnel.
- Patients experience altered sensation in the sensory distribution of the tibial nerve – the sole of the foot
- The motor function of the nerve can also be affected in severe disease, causing weakness and wasting of the intrinsic foot muscles
- Management can be conservative (physio, NSAIDs, corticosteroids) or surgical (tarsal tunnel release = cutting through the flexor retinaculum to decompress the tunnel)
What are the different landmarks of the PROXIMAL tibia?
- Tibial tuberosity
- Medial and lateral condyles
- Intercondylar tubercles - this is the main area for attachment of ligaments and menisci of the knee joint
- Soleal line
What are the landmarks of the DISTAL tibia?
- The distal end widens to assist with weight-bearing
- The medial malleolus is a bony projection continuing inferiorly on the medial aspect of the tibia, it articulates with the tarsal bones to form part of the ankle joint
- Laterally is the fibular notch, where the fibula is bound to the tibia – forming the tibiofibular joint
What is the fibula and what is its main function?
- The fibula is a bone located within the lateral aspect of the leg, its main function is to act as an attachment for muscles, and not as a weight-bearer.
What are the 3 main articulations of the fibula?
- Proximal tibiofibular joint
- Distal tibiofibular joint
- Ankle joint – articulates with the talus bone of the foot
On the posterior and lateral surface of the fibular neck, which nerve can be found?
Common fibular
What are the proximal tarsal bones?
Calcaneus (largest tarsal bone and lies underneath the talus where it constitutes the heel)
Talus (most superior of the tarsal bones & transmits the weight of the entire body to the foot - HIGH RISK OF AVASCULAR NECROSIS AS THE VASCULAR SUPPLY IS DEPENDENT ON FASCIAL STRUCTURES)
What are the bones of the midfoot (intermediate group)
Navicular bone
- On the plantar surface, there is a tuberosity for the attachment of part of the tibialis posterior tendon
What are the distal bones of the midfoot?
Cuboid
3x Cuneiforms
- They articulate with the metatarsals
- Cuboid is the farthest lateral, anterior to the calcaneus and behind the 4th and 5th metatarsals
How are the metatarsals numbered?
- They are numbered I-V (medial to lateral)
What are the different muscles found in the anterior compartment of the leg?
Tibialis anterior
Extensor digitorum longus
Extensor hallucis longus
Fibularis tertius
What is the role of the muscles in the anterior leg compartment?
Dorsiflexion and inversion of the foot at the ankle joint
- Extensor digitorum longus and extensor hallucis longus also extend the toes
The muscles in the anterior leg compartment are innervated by which nerve and artery?
Deep fibular nerve L4-S1
Anterior tibial artery
What is the origin & attachment, action and innervation of the tibialis anterior?
- Attachments: Originates from the lateral surface of the tibia, attaches to the medial cuneiform and the base of metatarsal I.
- Actions: Dorsiflexion and inversion of the foot.
- Innervation: Deep fibular nerve