Knee joint plan

Question 1

Classify the knee joint

Answer 1

Modified synovial hinge joint

Question 2

What are the bones / articulation of the knee joint?

Answer 2

Patella, femoral condyles and tibial plateau

Tibiofemoral and femoropatellar

Question 3

What type of cartilage is at the knee &what is its function?

Answer 3

Hyaline cartilage on articular surfaces

Reduce friction and shock absorption

Question 4

Describe the meniscus at the knee

Answer 4

Semilunar cartilages

- Make the knee joint more congruent and absorb shock

Question 5

Name the bursae at the knee joint

Answer 5

1. Suprapatellar bursa
2. Prepatellar bursa
3. Infrapatellar bursa
4. Pes anserine bursa
5. Semimembranosus bursa

Question 6

Where is the Suprapatellar bursa located?

Answer 6

Suprapatellar bursa - extension of synovial cavity of the knee that’s located between the quadriceps and the femur

Question 7

Where is the Prepatellar bursa located?

Answer 7

Between the apex of the patella & the skin

Question 8

Where is the Infrapatellar bursa located?

Answer 8

Deep - between patella tendon and tibia

Superficial - between patella tendon and skin

Question 9

Where is the Pes Anserine bursa located?

Answer 9

Pes anserinus is the area on the medial aspect of the knee where the tendons for gracilis, sartorius and semitendinosus muscles attach. The bursa is under the tendons separating them from the tibia

Question 10

Where is the Semimembranosus bursa located?

Answer 10

Posteriorly in the knee between semimbranosus and the medial head of gastrocnemius

Question 11

Describe the capsule of the knee joint

Answer 11

• Contains the whole joint
• Attached to articular margins
• Contains the patella anteriorly

Question 12

Describe the synovial membrane of the knee joint

Answer 12

It lines the capsule

• Secretes synovial fluid - which lubricates, removes waste and provides nutrients for cartilage
• The synovium bathes the area of the femoral condyles
• ACL and PCL are intracapsular but extrasynovial

Question 13

What are the ligaments at the knee joint?

Answer 13

1. ACL
2. PCL
3. MCL
4. LCL

Question 14

What are the permitted movements at the knee joint?

Answer 14

1. Flexion / Extension

2. Some medial / lateral rotation when knee is flexed

Question 15

How many degrees of freedom is at the knee?

Answer 15

1 degree (2 degrees as rotation into closed-packed position)

Question 16

What arteries supply the knee?

Answer 16

Branches from femoral, tibial and popliteal artery

Question 17

What nerves supply the knee?

Answer 17

Branches of obturator, femoral and sciatic nerves

Question 18

What muscles flex the knee?

Answer 18

1. Semimembranosus
2. Semitendinosus
3. Biceps femoris
4. Gastrocnemius

Question 19

What muscles extend the knee?

Answer 19

1. Rectus femoris
2. Vastus medialis
3. Vastus lateralis
4. Vastus intermedius

Question 20

What muscles laterally rotate the knee?

Answer 20

Biceps femoris

Question 21

What muscles medially rotate the knee?

Answer 21

1. Semimembranosus
2. Semitendinosus
3. Gracilis
4. Sartorius
5. Popliteus

Question 22

Gracilis

1. Origin
2. Insertion
3. Action
4. Innervation

Answer 22

1. Inferior border of pubic body near symphsis
2. Proximal medial surafce of tibia (part of pes anserinus)
3. Adducts thigh at hip
4. Obturator nerve (L3,L4)

Question 23

Semitendinosus

1. Origin
2. Insertion
3. Action
4. Innervation

Answer 23

1. Ischial tuberosity of os coxa
2. Proximal tibia, medial to tibial tuberosity (part of pes anserinus)
3. Extends thigh at hip
   Flexes leg at knee
   Medially rotates knee when knee is flexed
4. Tibial portion of sciatic nerve (L5, S1, S2)

Question 24

Semimembranosus

1. Origin
2. Insertion
3. Action
4. Innervation

Answer 24

1. Ischial tuberosity of os coxa
2. Posterior medial condyle of tibia
3. Extends thigh at hip
   Flexes leg at knee
   Medially rotates knee when knee is flexed
4. Tibial portion of sciatic nerve (L5, S1, S2)

Question 25

Biceps femoris 1. Origin 2. Insertion 3. Action 4. Innervation

Answer 25

1. Long head - Ischial tuberosity of os coxa Short head - distal linea aspera & lateral supracondylar ridge of femur 2. Long & short head - head of fibular and lateral condyle of tibia 3. Extends thigh at hip Flexes leg at knee Laterally rotates leg at knee when knee is flexed 4. Long head - Tibial portion of sciatic nerve (S1-S3) Short head -common peroneal nerve (L5, S1,S2)

Question 26

Rectus femoris 1. Origin 2. Insertion 3. Action 4. Innervation

Answer 26

1. Anterior inferior iliac spine and ilium above the acetabulum 2. Quadriceps tendon to base of patella and onto tibial tuberosity via the patellar ligament 3. Flexes thigh at hip Extend the knee 4. Femoral nerve (L2-L4)

Question 27

Vastus medialis 1. Origin 2. Insertion 3. Action 4. Innervation

Answer 27

1. Intertrochanteric line. It also attaches to the medial lip of linea aspera of femur 2. Quadriceps tendon to base of patella and onto tibial tuberosity via the patellar ligament 3. Flexes thigh at hip Extend the knee 4. Femoral nerve (L2-L4)

Question 28

Vastus lateralis 1. Origin 2. Insertion 3. Action 4. Innervation

Answer 28

1. Greater trochanter. It also attaches to the lateral lip of linea aspera of femur 2. Quadriceps tendon to base of patella and onto tibial tuberosity via the patellar ligament 3. Flexes thigh at hip Extend the knee 4. Femoral nerve (L2-L4)

Question 29

Vastus intermedius 1. Origin 2. Insertion 3. Action 4. Innervation

Answer 29

1. Anterior and lateral surafces of shaft of femur 2. Quadriceps tendon to base of patella and onto tibial tuberosity via the patellar ligament 3. Flexes thigh at hip Extend the knee 4. Femoral nerve (L2-L4)

Question 30

Sartorius 1. Origin 2. Insertion 3. Action 4. Innervation

Answer 30

1. Anterior superior iliac spine 2. Proximal tibia, medial to tibial tuberosity (part of pes anserinus) 3. Flexes thigh at hip Medially rotates knee 4. Femoral nerve (L2-L3)

Question 31

Popliteus 1. Origin 2. Insertion 3. Action 4. Innervation

Answer 31

1. Lateral surface of lateral condyle of femur 2. Proximal posterior surface of tibia, just above the soleal (popliteal line) 3. Medially rotates knee 4. Tibial nerve (L4, L5, S1)