Tibia Bone

TIBIA

• Tibia is the second largest bone (after femur).

PROXIMAL END (upper end)

• Proximal (upper) end of tibia includes medial & lateral condyles, forming tibial plateau.
• It also includes tibial Tuberosity & intercondylar area.
• Attachments on proximal end are:
• Medial  condyle: Semimembranous (posteriorly), capsule of knee joint, tibial (medial) collateral ligament (deep part), medial patellar retinaculum (anteriorly).
• Lateral condyle: illiotibial tract (anteriorly), capsule of superior tibiofibular joint.
• Tibial Tuberosity: Ligamentum patellae
• Intercondylar area (from anterior to posterior);

1. Anterior horn of medial meniscus
2. Anterior cruciate ligament (ACL)
3. Anterior horn of lateral meniscus
4. Posterior horn of lateral meniscus
5. Posterior horn of medial meniscys
6. Posterior cruciate ligament (PCL)

• Upper end of tibia is the growing end. The secondary center for upper end appears just before birth & fuses with shaft at around 16-18 years.

SHAFT

• Shaft of tibia is plasmoid in shape.
• It has three borders (anterior, medial & interosseous or lateral) and three surfaces (medial, lateral & posterior).
• Anterior border (also c/d shin) and medial surface are subcutaneous. 
• Tibia is the commonest site of osteomyelitis from direct contamination as well as from hematogenous spread. 
• Nutrient artery to tibia is  the largest nutrient artery. It is a branch of posterior tibial artery.

DISTAL END

• It is slightly expanded with a projection downwards & medially i.e medial malleolus.
• Medial malleolus gives attachment to deltoid ligament (medial collateral ligament) of ankle.
• Secondary center of ossification for lower end appears during 1st year forms malleolus by 7th years & fuses with shaft by 15-17 years.