Fascia of Plantar Foot Flashcards
Peroneal retinacula
Located laterally
- Superior peroneal retinacula
- Inferior peroneal retinacula
Superior peroneal retinacula
- Crosses superficial to peroneus longus and brevis
- Originates at the posterior border of the lateral malleolus (of fibula)
- inserts into the lateral surface of the calcaneus and the tendocalcaneus (Achilles)
Inferior peroneal retinacula
- Originates at the lateral rib of sinus tarsi
- Inserts into the lateral surface of the calcaneus and the peroneal trochlea
- Forms two tunnels between the origin and insertion
- Superior tunnels encloses the peroneus brevis tendon
- Inferior tunnel encloses the peroneus longus tendon
NOTE: ONLY deep fibers form the tunnels, superficial fibers lie flat over teh ligaments
Flexor retinaculum
Located medially
- Recall that the peroneal retinacula is located laterally
- AKA lacinate ligament or medial annular ligament
- Triangular in shape
Attachment sites of flexor retinaculum
- Anteromedial surface of the medial malleolus
- Continuous with deep fascial of the leg
- Continuous with dorsal aponeurosis of the foot
- Superior border of the abductor hallucis
- Medial process of calcaneal tuberosity (FFA)
Description of flexor retinaculum formation
Flexor retinaculum forms one tunnel with 4 compartments
NOTE: the flexor retinaculum is the “roof” of the tarsal tunnel or the talocalcaneal tunnel
Compartments of flexor retinaculum
- Compartment 1 = Tibialis posterior
- Compartment 2 = Flexor digitorum longus
- Compartment 3 = Posterior tibial artery and nerve
- Compartment 4 = Flexor hallucis longus
NOTE: tibialis posterior is found directly posterior to the medial malleolus and it continues back from there
REMEMBER: Tom (1), Dick (2), Very Nervous (3), Harry (4)
Plantar aponeurosis
- Formed by the deep fascia of the plantar foot
- Thickens where the foot contacts the floor
- Fat globules are found superficial to the aponeurosis and are considered to be shock absorbers
3 parts of the plantar aponeurosis
- Central
- Lateral
- Medial
Central part of plantar aponeurosis
- Thickest of the three parts
- The central portion becomes thinner as it passes anteriorly
Attachments of central plantar aponeurosis
- Posterior attachment = medial process of calcaneal tuberosity (“P” of LAP)
- Anterior attachment = 5 processes to the 5 digits
- Digital processes attach to the skin, tendon sheath
- Superficial stratum attaches to the skin of the transverse sulcus
- Deep stratum divides into two slips, one on each side of the flexor tendons) then blends with the tendon sheath
- Between the digital processes of the central plantar aponeurosis we see digital nerves, vessels and lumbrical tendons
Lateral part of plantar aponeurosis
- Found superficial to abductor digiti minimi muscle of the 1st layer
- Thicker proximally, thins out distally (same as central portion)
- Creates a strong band between the lateral process of the calcaneal tuberosity and the base of the 5th metatarsal
Attachments of lateral part of plantar aponeurosis
- Posterior attachment = lateral process of calcaneal tuberosity (“P” in LAP)
- Anterior attachment = base of 5th metatarsal
Medial part of plantar aponeurosis
- Lies superficial to abductor hallucis (1st layer)
- Attaches posterior to the flexor retinaculum
Intermuscular septa
- There are two vertical septa which dive deep into the foot
- They are formed by the junction of the lateral and central parts of the plantar aponeurosis
- Creates 3 compartments (medial, lateral, central)
Medial compartment
Contains intrinsic muscles of the 1st digit
Lateral compartment
Contains intrinsic muscles of the 5th digit
Central compartment
Contains quadratus plantae, flexor digitorum brevis, lumbricals and interosseous muscles