Leg and Knee

Question 1

Patella

Answer 1

Articulates with the trochlear groove of the distal femur.

Question 2

Tibia and Fibula (3)

Answer 2

Joined by a fibrous interosseous membrane.

Tibia is weightbearing

Fibia functions primarily for muscle attachments, forms part of the ankle joint, and acts as a pulley for the fibularis longus and fibularis brevis muscle tendons.

Question 3

Knee Joint

Answer 3

Largest of the synovial joint

The knee consists of the articulation between the femur and the tibia (biaxial condylar synovial joint) and between the patella and the femur

Question 4

Distal knee joints

Answer 4

Tibiofemoral + Patellofemoral

Question 5

Vascular supply for knee

Answer 5

Arises from genicular branches of the popliteal artery, the inferior
continuation of the femoral artery.

Question 6

Osgood-Schlatter disease (OSD)

Answer 6

Partial avulsion of the tibial tuberosity.

Repetitive stress on the tuberosity may cause it to separate (avulse) from the tibia. The avulsed fragment continues to grow, with the intervening space filled with new bone or fibrous connective tissue, so that the tibial tuberosity is enlarged.

Common in children who engage in vigorous physical activity than in less active children.

Question 7

Subluxation of the patella

Answer 7

Presents with tenderness along the medial patellar aspect and atrophy of the quadriceps tendon, especially the oblique portion medially derived from the vastus medialis.

Question 8

Patellar ligament rupture

Answer 8

Occurs just inferior to the patella as a result of direct trauma
in younger people.

Quadriceps tendon rupture occurs mostly in older individuals, from either minor trauma or age-related degenerative changes,

Question 9

Rupture of the anterior cruciate ligament (ACL) (3)

Answer 9

Common athletic injury usually related to sharp turns, when the knee is twisted while the foot is firmly on the ground.

The patient may hear a popping sound and feel a tearing sensation associated with acute pain.

Joint stability can be assessed by using the Lachman and anterior drawer tests.

Question 10

Ligament injuries (sprains) of the knee (3)

Answer 10

First degree: stretched ligament with little or no tearing.
Second degree: partial tearing of the ligament with joint laxity.
Third degree: complete rupture of the ligament, resulting in an unstable joint

Question 11

Fibrocartilaginous menisci injury

Answer 11

Often torn when the knee undergoes a twisting injury.

Patients complain of pain at the joint line, and the involved knee “gives way” when flexed or
extended.

Question 12

Rupture of the tibial collateral ligament

Answer 12

Involves a tear of the medial meniscus because the ligament and meniscus are attached.

Question 13

Iliotibial Tract (Band) Syndrome

Answer 13

Common in runners and presents as lateral knee pain, often in the midrange of flexion, between 20 and 70 degrees of knee flexion.

Question 14

Proximal (superior) tibiofibular joint

Answer 14

Joint between the fibular head and the lateral condyle of the tibia.

The joint is stabilized by a wider and stronger anterior ligament and a narrow weaker posterior ligament; this joint allows for some minimal gliding movement.

Question 15

Distal tibiofibular joint (tibiofibular syndesmosis)

Answer 15

Formed by the rough, convex surface of the medial side of the distal end of the fibula, and a rough concave surface on the lateral side of the tibia.

Question 16

Muscles of posterior compartment of leg (7)

Answer 16

1. gastrocnemius
2. soleus
3. plantaris
4. popliteus
5. flexor hallucis longus
6. flexor digitorum longus
7. tibialis posterior

Question 17

Gastrocnemius

Answer 17

Origin:

• Lateral head: lateral aspect of lateral condyle of femur
• Medial head: popliteal surface of femur, superior to medial condyle

Insertion: Posterior surface of calcaneus via calcaneal tendon

Fx: Plantarflexes foot at ankle. raises heel during walking, flexes leg at knee joint

Question 18

Soleus

Answer 18

Origin: Posterior aspect of head of fibula, superior quarter of posterior surface of fibula, soleal line, and medial border of tibia

Insertion: Posterior surface of calcaneus via calcaneal tendon

Fx: Plantarflexes foot at ankle; steadies foot on leg

Question 19

Plantaris

Answer 19

Origin: Inferior end of lateral supracondylar line of femur and oblique popliteal ligament

Insertion: Posterior surface of calcaneus via calcaneal tendon

Fx: Weakly assists gastrocnemius in plantarflexing ankle and flexing knee

Question 20

Popliteus

Answer 20

Origin: Lateral condyle of femur and lateral meniscus
Insertion: Posterior surface of tibia, superior to soleal line
Fx: Weakly flexes leg at knee and unlocks it

Question 21

Flexor hallucis longus

Answer 21

Origin: Inferior two thirds of posterior surface of fibula and inferior part of interosseous membrane

Insertion: Base of distal phalanx of great toe (hallux)

Fx: Flexes great toe at all joints and plantarflexes foot at ankle; supports longitudinal arches of foot

Question 22

Flexor digitorum longus

Answer 22

Origin: Medial part of posterior surface of tibia inferior to soleal line and by a
broad tendon to fibula

Insertion: Bases of distal phalanges of lateral four digits

Fx: Flexes lateral four digits; plantarflexes ankle; supports longitudinal arches of foot

Question 23

Tibialis posterior

Answer 23

Origin: Interosseous membrane, posterior surface of tibia inferior to soleal line, and posterior surface of fibula

Insertion: Tuberosity of navicular, cuneiforms, and cuboid, and bases of 2nd–4th
metatarsals

Fx: Plantarflexes foot at ankle, and inverts foot

Question 24

Anterior leg compartment muscles (4)

Answer 24

1. Tibialis anterior
2. Extensor hallucis longus
3. Extensor digitorum longus
4. Fibularis tertius

Question 25

Tibialis anterior

Answer 25

Origin: Lateral condyle and superior half of lateral tibia and interosseous membrane

Insertion: Medial and inferior surfaces of medial cuneiform and base of 1st metatarsal

Fx: Dorsiflexes foot at ankle, and inverts foot

Question 26

Extensor hallucis longus

Answer 26

Origin: Middle part of anterior surface of fibula and interosseous membrane
Insertion: Dorsal aspect of base of distal phalanx of great toe (hallux)
Fx: Extends great toe; dorsiflexes foot at ankle

Question 27

Extensor digitorum longus

Answer 27

Origin: Lateral condyle of tibia and superior 2/3 of anterior surface of fibula and interosseous membrane

Insertion: Middle and distal phalanges of lateral four digits

Fx: Extends lateral four digits, and dorsiflexes foot at ankle

Question 28

Fibularis tertius

Answer 28

Origin: Inferior third of anterior surface of fibula and interosseous membrane
Insertion: Dorsum of base of 5th metatarsal
Fx: Dorsiflexes foot at ankle and aids in foot eversion

Question 29

Muscles of lateral leg compartment (2)

Answer 29

1. Fibularis longus

2. Fibularis brevis

Question 30

Fibularis longus

Answer 30

Origin: Head and superior two thirds of lateral surface of fibula
Insertion: Base of 1st metatarsal and medial cuneiform
Fx: Evert foot, and weakly plantarflex foot at ankle

Question 31

Fibularis brevis

Answer 31

Origin: Inferior 2/3 of lateral surface of fibula
Insertion: Dorsal surface of tuberosity on lateral side of 5th metatarsal
Fx: Evert foot, and weakly plantarflex foot at ankle

Question 32

Innervation and blood supply of anterior leg compartment

Answer 32

Deep fibular nerve + Anterior tibial artery

Question 33

Blood supply and innervation of posterior leg compartment

Answer 33

Posterior and fibular artery + Tibial nerve