Review of the Knee Joint

Name the ligament

Semitendinosus• Action:

– Flexion of the knee– Internal rotation of the knee

Name the muscle and its action(s)

1. Vastus Medialis

2. Rectus Femoris

3. Vastus Lateralis

1.

3.

2.

Tibia & FibulaMedial condyleLateral condyleHead of fibula

? =? =? =

Sartorius

Action: Flexion at the knee

Name the muscle and its action

Semimembranosus

• Action: – Flexion of the knee– Internal rotation of the knee

Name the muscle and its action(s)

1. Anterior cruciate ligament

2. Lateral collateral ligament

3. Lateral meniscus4. Posterior cruciate

ligament5. Medial collateral

ligament6. Medial meniscus

1.

2.

3.

4.

5.

6.

                     

Popliteus

• Action: – Flexion of knee– Internal rotation of the knee

Name the muscle and its action

2.

3.1.

1 = Lateral Meniscus2 = Patella3 = Medial meniscus

• Vastus medialis

• Rectus femoris

• Vastus lateralis

Name the colored muscles

1

23

Femur

? =? =? =

Lateral condyleMedial condyleIntercondylar fossa

Gracilis

Action - flexion at the knee

Name the muscle and its action

1.

2.

3.

1. = Vastus lateralis

2. = Rectus femoris

3. = Vastus medialis

What is the Q angle?

• The angle between the line of pull of the rectus femoris and the patellar ligament.

Review

• Define “screw home” movement.– Locking of the knee during full extension

and external rotation.

• Which type of rotation occurs during “unlocking” of the knee?– Internal rotation and flexion

1.

2.

3.3.

4.

1. = Anterior cruciate ligament2. = Lateral collateral3. = Lateral meniscus3. = Medial collateral4. = Medial mieniscus

Name the muscles.

1.

2.

3.

1 = Vastus lateralis

2 = Vastus intermedius

3 = Vastus medialis

Fibula

Head Lateral malleolus

? =? =

1.Semitendonosis

2.Biceps femoris

3.Semimembranosis

Name the muscles

1.2.

3.

Biceps femoris• Action:

– Flexion of knee– External rotation of the knee

Name the muscle and its action

Tibia

Medial condyle

Lateral condyle

Tibial tuberosicty

? =? =? =

Name two functions of the menisci.

1.Stabilization2.Shock absorption3.Lubrication

Name the muscle and its action(s)

SartoriusAction: Flexion at the knee

Questions

• What is a uniarticulate muscle?– A muscle that crosses one joint

• What is a biarticulate muscle?– A muscle that crosses two joints.

• What is a disadvantage of a biarticulate muscle?– They are weaker during movement at both

of the joints.

2.

1.

1 = Lateral meniscus2 = Medial meniscus

Femur1. Medial condyle2. Lateral condyle3. Intercondylar fossa

Popliteus

• Action: – Flexion of the knee– Internal rotation of the knee

Name the muscle and its action(s)

Tibia 1. 2.

1. Lateral condyle2. Medial condyle

Biceps femoris

Action: Flexion of kneeExternal rotation of the knee

Name the muscle and its action

FibulaHead HeadProximal

Distal

1.

2.

3.

• Action: – Extension of the knee

Name the muscles and its action

1. Vastus lateralis

2. Vastus intermedius

3. Vastus medialis

LIGAMENTS

1. ACL

2. Lat. Collat.

3. Lat. Men.

4. PCL

5. Med. Collat.

6. Med. Men.

1.

2.

3.

4.

5.

6.

Meniscus1. ACL

2. Lateral men.

3. PCL

4. Medial men.

1

24

3

Rectus femoris

• Action: – Extension of knee

Name the muscle and its action

QUESTIONS?