661 osteology of knee

distal femur and the proximal tibia

the knee joint is at the

Modified hinge joint

what type of joint is the knee joint

passive rotation

what type of rotation happens at the knee joint

1

- flexion and extension

how many degrees of freedom does the knee joint have

two longest levers in the body = a lot of force on joint going through the knee

the knee joint unites the

lateral epicondyle

acts as the COR for knee in the sagittal plane

linea aspera

a lot of muscles have an origin based off of

intercondylar fossa

• gap/space between 2 condyles

• ACL & PCL attach here

• more narrow in females

intercondylar eminence

ACL & PCL attach to the

tibial plateu

the surface that top of tibia where medial and lateral meniscus sit on

another name for the proximal tibiofibular joint

the synovial joint

transfer forces from the biceps femoris and LCL

function of the synovial joint

intercondylar fossa

where the attachments for the cruciates are

- risk factor for ACL rupture

sesamoid bone (smaller/sesame seed) & the biggest one in the body

what type of bone is the patella

femur in the trochlear groove

the patella articulates with the

base

proximal part of patella

apex

distal part of patella

lateral and medial

facets of the patella

quad tendon (superior)

patellar tendon (inferior)

IT band and lateral retinaculum (lateral)

medial retinaculum and VMO (medial)

patella attachments for stability

fibrocartilage = more type 1 collagen than 2 and withstands compressive forces better (shock absorbers)

structure of the meniscus

- protect articular cartilage

- transmit loads across the surface of the joint

- enhance joint stability

- assists in lubrication

function of meniscus

C

medial meniscus is what shape

O

lateral meniscus is what shape

anterior/posterior horns

more stability, less movement, more susceptible to injury
strongest attachment from meniscus to tibia

• medial meniscus: strong attachment to MCL, less movement = more injury of medial meniscus which gives more stability.

• lateral meniscus: does not have an attachment = more mobility and less likely for injury to occur

medial vs lateral meniscus

fibrous capsule

thickenings in the capsule (collateral ligaments & posterior capsule)

bursa

• 14 in knee

• cushions but not highly innervated

• fluid filled sacs

• pouch

intrapatellar fat pad

acts as cushion and HIGHLY INNERVATED

- flat band/thickening in the joint capsule

- superior to medial epicondyle (femur) and inferior to medial condyle (tibia)

MCL structure

valgus stress = prevents Abductions

primary function of MCL

cord-like (think guitar)

lateral epicondyle of the femur to the fibular head

LCL structure

varus stress = prevents Adduction (bowl legged)

primary function of LCL

gluteus maximums and TFL

iliotibial band (IT band) origin

1. lateral femur

- fat pad deep to IT band

2. lateral patella (via lateral patellofemoral ligament)

3. Gerdy's tubercule

insertion of IT band

lateral knee stability

function of IT band

cruciates = cross

ACL and PCL

tibia

cruciates are named by their attachments to the

superior, lateral, and posterior

ACL runs

resists anterior translation of the tibia on the femur

function of ACL

superior, medial, and anterior

PCL runs

resists posterior translation of the tibia on the femur

function of PCL