Tibiofibular and Ankle Joints Flashcards
In which part of the tibia do fractures take longer to heal?
the distal third- because the blood supply is poorer
What is the soleal line?
an oblique line posteriorly on the tibia that is the attachment for soleus
Which extends further, the medial or the lateral malleolus?
lateral
Why is the fibula often used in bone grafts?
because it is non weight bearing and highly vascular
What type of joint is the superior tibiofibular joint?
a plane synovial joint - gliding movement occurs
What type of joint is the inferior tibiofibular joint?
a fibrous joint (syndesmosis)
What are the bones of the foot?
tarsal bones (calcaneus, talus, navicular, 3 cuneiforms and cuboid), 5 metatarsals and 14 phalanges
Which foot bone articulates at the ankle joint?
talus
Which foot bone does the achilles tendon attach to?
calcaneus
Which metatarsal is commonly fractured?
the second metatarsal - because it is long and thin and is wedged between the 1st and 3rd so easily develops stress fractures
What is the role of the sesamoid bones under the heads of the metatarsals?
create a cushioning effect and create space for nerves and vessels to run
What type of joint is the talocrural joint?
a synovial hinge joint
What is the mortise?
the socket at the base of the tibia and fibula formed by the medial and lateral malleoli and the inferior transverse ligament
What is the impact on movement of having the lateral malleolus extend more distally than the medial malleolus?
the axis of movement is oblique so plantar flexion is associated with inversion and dorsiflexion is associated with eversion
Why is dorsiflexion more stable than plantarflexion?
because the talus is wider anteriorly than posteriorly so the joint is more congruent in dorsiflexion
What is the deltoid ligament?
the medial collateral ligament
Which is stronger, the medial or lateral collateral ligament?
the medial
What movements occur at the subtalar and talocalcaneonavicular joints?
inversion and eversion (the joints are functionally paired)
What is the role of the spring ligament?
maintains the position of the talus
What is the sinus tarsi?
the gap between the talus and calcaneus - contains the interosseus talocalcaneal ligament
Why does the talus have a poor blood supply and how does it get is blood supply?
poor blood supply because no muscles attach - gets its blood supply through a vascular sling in the sinus tarsi
What type of joint is the calcaneocuboid joint?
a plane synovial joint
Why joints allow pronation and supination?
subtalar and TCN + calcaeneocuboid
What arches are present in the foot?
medial and lateral longitudinal and transverse
What supports the arches of the foot?
muscles, ligaments and the plantar aponeurosis
