Tibia, Fibula, Ankle, and Foot

PSK 4U

Mr. S. Kelly

North Grenville DHS

Tibia

• Articulates the distal portion of the knee joint with the ankle joint

• Aka the “shin”, found medial and anterior to the smaller fibula

• Gender difference: in males, the direction is more vertical, more oblique in females to compensate for a more oblique shape of the femur

Tibia Structures

• Medial and lateral condyles: distal borders of the knee joint

• Interosseus membrane: connects tibia and fibula along the body or shaft of the bones

• Fibular notch: where the fibula articulates (distally)

• Medial malleolus: medial ankle protrusion

• Intercondylar eminence: splits intercondylar area into anterior and posterior (anterior area is ACL attachment site

Tibial Tuberosity

• Attachment site for the patellar ligament

• Terminal point of the “lever” (quads, suprapatellar ligament, patella, patellar ligament) that extends the knee AND prevents knee from collapsing on foot-strikes

• Fractured rarely, but most commonly in adolescents (avulsion fractures)

View(s) of the knee joint…

Fibula

• Located lateral to the tibia

• Connected to tibia anteriorly and distally

• Distal end articulates anterior to proximal end (it is on a bit of an angle)

• Forms lateral border of ankle joint

Fibula Structures

• Head: articulates below the tibia

• Lateral malleolus: lateral ankle protrusion

The Ankle

• Distal ends of tibia and fibula articulate with the talus

• The tibial articulation with the talus bears more weight than the fibular articulation (size difference)

• Numerous ligaments allow for the wide range of motion at this joint while bearing a relatively large weight

The Ankle and Foot

Talus

• Second-largest tarsal bone

• Large portion of the bone is covered in articulating cartilage

• Blood supply is “retrograde” meaning that the blood enters at the distal end

Calcaneus

• Heel bone

• Largest bone of the foot

• Calcaneal Tuberosity: insertion point for the Achilles tendon, origin for tendons (muscles) of the foot

Tarsal Bones

• Be able to locate and identify all the tarsal bones as follows:

• Cuneiform(s): medial, intermediate, lateral

• Navicular

• Cuboid

Lateral Ankle Ligaments

• Anterior Talofibular

• Posterior Talofibular

• Calcaneofibular

• Posterior Tibiofibular

• Anterior Tibiofibular

• These are, with lateral talocalcaneal, the most common ligaments involved in inversion sprains

Medial Ankle Ligaments

• The deltoid ligament, shaped like the Greek letter “delta”, also like a triangle

• From posterior to anterior:

• Posterior tibiotalar

• Tibiocalcaneal

• Anterior tibiotalar

• Tibionavicular

• Most commonly involved in painful eversion sprains

Metatarsals

• Numbered 1-5 from medial to lateral

• Similar to the metacarpals in the hand

• PHALANGES: similar to those of hand

• Be familiar with the joint names!!