ligaments and joint structures

introduction to anatomy and physiology

define a ligament

connects 2 bones together

what is a ligament made from

strong and dense connective tissue that is rich in collagen so therefore it helps to stabilise a joint

difference between a ligament and tendon

a ligament connects bone to bone WHEREAS a tendon connects bone to muscle

anterior cruciate ligament (ACL) attachments and force it resists

attachments - posterior side of femur to the anterior side of the tibia

force it resists - anterior translation of tibia (tibia moving too far forward)

posterior cruciate ligament (PCL) attachments and force it resists

attachments - medial femoral condyle to in-between the medial and lateral epicondyles in the posterior side of tibia

force it resists - posterior translation of tibia (tibia moving to far back)

medial collateral ligament (MCL) attachments and force it resists

attachments - medial femoral epicondyle to the medial surface of the tibia

force it resists - valgus force (lower leg forced outwards away from the midline of the body)

lateral collateral ligament (LCL) attachments and force it resists

attachments - lateral femoral condyle to the head of the fibula

force it resists - varus stress (lower leg forced inwards towards midline of the body)

anterior talofibular ligament (ATFL) attachments and force it resists

attachments - lateral malleolus (fibula) to the lateral talus

force it resists - inversion during plantar flexion and anterior translation of the talus (talus moving too far forwards)

calcaneofibular ligament (CFL) attachments and force it resists

attachments - lateral malleolus to the lateral surface of the calcaneus

force it resists - inversion of the foot during plantar and dorsiflexion

deltoid (medial) attachments and force it resists

attachments - medial malleolus of the tibia and then branches out to 3 bones in the foot which are the talus, calcaneus and navicular

force it resists - eversion of the ankle and lateral shift of the talus (talus moving sideways out from under the tibia)

define labrum

ring of fibrocartilage which attaches to the edge of the ball and socket joint and so deepens the socket, increasing joint stability

define meniscus

fibrocartilage around the knee that helps absorb shock, stabilises the joint and distributes the load

define bursa

small sac filled with fluid to reduce friction and act as a cushion

define fat pad

soft fat tissue around the joint which absorbs shock and reduces friction