Calcaneus Flashcards
Dimensions of Calcaneus
Strongest bone
Rectangular
Elongated anterior-posterior
Width = height = 50% of Length
Shape of Dorsal surface
concave front to back
Convex side to side
Facets of anterior third of dorsal calcaneal surface
Anterior facet - lies close to middle facet (often joined)
Middle facet - supported by sustentaculum tali
Articulate with talus
Calcaneal sulcus
Deep depression on anterior third of dorsal calcaneus between middle/posterior facet (middle third)
Combines with deep groove of plantar surface of talus to form tarsal sinus and tarsal canal
Tarsal canal
medial to tarsal sinus
Directed anterolateral and continuous with tarsal sinus
Which ligament lies within tarsal canal
Interosseous talocalcaneal ligament
Tarsal sinus location
lies at lateral end of tarsal canal
Ligaments attached to tarsal sinus (7)
Extensor digitorum brevis Inferior extensor retinaculum Inferior peroneal retinaculum cervical ligament bifurcate ligament dorsal calcaneocuboid ligament lateral calcaneocuboid ligament
Middle third of dorsal calcaneal surface
contains posterior articular facet
Posterior articular facet
oval shaped
Largest of 3 facets
Posterior third of dorsal calcaneal surface
smooth nonarticular area with numerous vascular foramina
Ligaments attaching to posterior third of dorsal calcaneal surface (2)
Posterior talocalcaneal ligament
Fibulocalcaneal ligament
Plantar calcaneal surface
Convex from side to side Wider posteriorly (triangular)
Calcaneal tuberosity
Posterior limit of plantar surface
Depressed in middle
Prolonged into lateral and medial process on each side
Lateral process of calcaneal tuberosity attachments (4)
Posterolateral calcaneal tuberosity
Abductor digiti quinti
Lateral head of quadratus plantae
Long plantar ligament
Plantar aponeurosis
Medial process of calcaneal tuberosity attachments (7)
posteromedial calcaneal tuberosity
Broader and larger Abductor hallucis Medial head of quadratus plantae Long plantar ligament Plantar aponeurosis Flexor retinaculum Flexor digitorum brevis Abductor digiti quinti
Middle depression attachments (2)
Long plantar ligament
Abductor digiti quinti
Anterior calcaneal tuberosity
located near anterior border of plantar calcaneus
Plantar calcaneocuboid ligament (short plantar) attaches here
Anterior calcaneal surface
Smallest surface
Contains triangular facet for cuboid
Triangular facet of anterior calcaneus
Articulates with cuboid
Convex transversely
Concave vertically
Saddle shaped
What attaches to medial margin of triangular facet of anterior calcaneus
plantar calcaneonavicular ligament (spring)
Posterior calcaneal surface
forms prominence of heel
contains three areas separated by superior and inferior horizontal lines
Superior posterior calcaneal surface
smooth
covered by bursa lying deep to tendo calcaneus
Middle posterior calcaneal surface
Contains rough area for attachment of tendo calcaneus and plantaris (plantaris attaches medially or they attach together)
Inferior posterior calcaneal surface
rough
covered by fatty fibrous tissue
Lateral calcaneal surface
broader posteriorly than anteriorly
most vulnerable surface
Contains 1-3 tubercles: retrotrochlea eminence, peroneal trochlea, 3rd tubercle
Retrotrochlear eminence
most constant feature
Located in middle 1/3 of lateral surface
lies directly behind peroneal trochlea
Due to bony trabeculae within calcaneus that fan out from articular surface
Peroneal trochlea
ridge of bone formed by groove for tendon of peroneus longus
present 33% of time
Lies anterior to retrotrochlear eminence
Groove for tendon of peroneus longus lies inferior and posterior
Rarely: second groove located superior and anterior to peroneal trochlea formed by peroneus brevis
What attaches to peroneal trochlea
deep fibers of inferior peroneal retinaculum
Third tubercle of lateral calcaneus
Located posterior and superior to retrotrochlear eminence
Ligaments associated with third tubercle
calcaneofibular ligament attaches when tubercle is present
lateral talocalcaneal ligament attaches just anterior and superior to calcaneofibular ligament (partially overlies LTCL)
Medial calcaneal surface
deeply concave
contains plantar nerves and vessels within hollow
Attachments to medial calcaneal surface
Medial head of quadratus plantae is more extensive here than on medial process of plantar surface
Sustentaculum tali
shelf-like projection from medial surface
superiorly - articulates with talus
Inferiorly - grooved by tendon of flexor hallucis longus
Structures attached to sustentaculum tali (4)
tibiocalcaneal ligament (part of deltoid)
medial talocalcaneal ligament
recurrent band of tibialis posterior (partial)
plantar calcaneonavicular (spring) ligament
