GL 22 and GL 23: The Hip and Knee Joints

Question 1

What type of joint is the hip joint?

Answer 1

A synovial joint—designed for stability and weight bearing

Question 2

What are the articulations of the hip joint?

Answer 2

head of the femur and acetabulum of the pelvic bone

Question 3

What are the ligamentous support of the hip joint?

Answer 3

Iliofemoral—strongest ligament in the body
Ischiofemoral
Pubofemoral

Question 4

How are the ligaments arranged in the hip joint?

Answer 4

In a spiral fashion— to stabilize the joint, reduce muscular energy needed, limits flexion and adduction

Question 5

What is the ligament of the head of the femur?

Answer 5

Ligament of teres

Question 6

What does the ligament of teres caries?

Answer 6

A small branch of the obturator artery—which continues blood supply to head of the femur

Question 7

What is the vascular supply of the hip joint?

Answer 7

small branch of the obturator, medial and lateral circumflex femoral arteries

Question 8

What is the innervation of the the hip joint?

Answer 8

Articular branches of: femoral, obturator, superior gluteal and the nerve to the quadratus femoris

Question 9

What is the safe and unsafe areas for the gluteal intramuscular injection?

Answer 9

Safe: Outer Upper Quadrant

Unsafe: Lower medial quadrant—sciatic nerve runs through here

Upper medial—-superior gluteal nerve runs through here.

Question 10

What are the normal characteristics of gait and anatomical structures structures influencing normal?

Answer 10

60 % stance
40 % swing

Smooth gait:pelvic tilt, pelvic rotation, moving knees toward the midline, flexion of knees, interaction b/w hip and knee acts to minimize fluctuations in the change of center of gravity to maintain locomotion and produce smooth efficient gait

Question 11

What are the characteristics of an abnormal gait, specifically antalgic gait?

Answer 11

A gait developed when you’re trying to avoid pain in the area

i. stride length is shortened
ii. cane in opposite hand
iii. opposite side of pelvis rises

Question 12

What are the characteristics of an abnormal gait, specifically trendelenburg gait?

Answer 12

associated with a positive Trendelenburg sign

i. gluteus medius and gluteus minimus are impacted (weak/paralyzed abductor muscles)
ii. superior gluteal nerve is affected
iii. dropped hip over the swing limb (unaffected limb will droop)
iv. patient will exhibit trunk lean to the affected side (opposite of droop side)

Question 13

What can cause abnormal gait?

Answer 13

fracture of the greater trochanter

lumbar spinal pathology (bulging disk impinging on nerves)

Question 14

What are the clinical implications of the hip with the change in age?

Answer 14

Early in the development, the epiphyseas and the metaphyseas have different blood supplies.

Infants and Children (until 8 y/o): head of femur gets arterial supply by a direct branch of the obturator artery

As you get older, fractures become more damage b/c /you have less collateral blood supply so you’re more likely to have avascular necrosis

Question 15

What are the structures at risk from a fracture of the femoral neck or dislocation of the hip and explain the functional consequences of these injuries.

Answer 15

Damage to Femoral Neck:

will affect the femoral head b/c the neck supplies the arterial supply for the head. This could lead to avascular necrosis

Medial femoral circumflex artery is the one that is most likely to get damaged

Hip Dislocation

Posterior: hip is flexed, internally rotated, and adducted
Hip dislocation can affect ligaments supporting the hip

Question 16

Differentiate between a Trendelenburg sign and a Trendelenburg test.

Answer 16

Trendelenburg Sign: Pelvis drops when lifting the leg opposite to the weak gluteus muscles (Test would be asking the patient to demonstrate that)

Question 17

Explain the functional significance of anastomosis between branches of the major arteries of the knee.

Answer 17

1. ) Deep femoral artery—> lateral and deep circumflex femoral arteries
2. ) Femoral artery–>descending genicular artery and perforating branches of perforating arteries
3. ) Popliteal artery–> Superior and inferior medial and lateral arteries

All anastomose at the knee

Question 18

What factors are responsible for maintaining stability of the knee?

Answer 18

static —immovable (patella and tibia)

dynamic—movable (ligaments)

Popliteal Muscle (stabilizes knee in flexion and extension; unlocking mechanism–lateral rotation of femur on tibia)

Horns of the Meniscus ----
Posterior Horn (keeps knee from dislocating; most common place for meniscus tear)

Question 19

What are the ligaments of the knee?

Answer 19

Collateral Ligaments (medial, lateral)— reinforce synovial joint

Cruciate Ligaments (anterior, posterior) –connects femur to tibia

Patellar Ligament: (continuation of the quadriceps femoral tendon) —-Stabilizes the patella
Attaches to the tibial tuberosity

Question 20

What is Oschgod Slotter’s disease ?

Answer 20

Inflammation of the patellar ligament that leads to pain in adolescents

Question 21

Which side of the menisci helps w/ congruency (freely movable, not attached to a ligament) ? Lateral or medial?

Answer 21

Lateral menisci

Question 22

Which side of menisci is attached to the MCL, more constrained so it’s easily damaged? Lateral or medial?

Answer 22

Medial

Question 23

What are the two zones of the meniscus?

Answer 23

Red zone: has vasculature

White Zone: has no vasculature stimulation

Question 24

What is the clinical correlations of the zones in the meniscus?

Answer 24

If there is a tear in the white zone, it is more difficult to heal because the is no vascular stimulation

Question 25

What is the unhappy triad and what test confirms that this occurs?

Answer 25

A tear in the ACL, MCL and meniscus

Anterior Drawer Test

Question 26

What is the fibrous membrane of the knee?

Answer 26

It is formed and reinforced by extensions from tendons of the surrounding muscle

Question 27

What is the anatomy and function of the anterior and posterior cruciate ligaments?

Answer 27

ACL: anteriorly, prevents anterior tibia dislocation; Also has proprioceptors for spatial relations——Issues w/ this would make it hard to orient yourself during walking

PCL: posteriorly, prevents posterior dislocation of fixed femur

Question 28

What are the tests performed to confirm that the ACL is torn?

Answer 28

Lachman Test

Pivot Test

Cross Over Test

Anterior Drawer Test

Question 29

What are the tests performed to confirm that the PCL is torn?

Answer 29

Posterior Drawer Test

Question 30

What are the articular surfaces of the knee joint?

Answer 30

Femur and Tibia

Patella and Femur

Question 31

What is the cause of housemaid’s knee?

Answer 31

Excessively compressing the pre-patellar bursa, which leads to pain and swelling

Caused by constant friction irritating the lubricating sac anterior to the patella

Question 32

Explain the consequence of a lesion of the superficial and deep fibular nerves just distal to their origin.

Answer 32

Deep Fibular: leads to foot drop

Common Fibular: leads to foot drop

Superficial Fibular: weakened eversion (you would still have some b/c of the fibularis tertius)

Question 33

Explain the consequence of a lesion of the tibial nerve in the popliteal fossa.

Answer 33

Loss of plantarflexion

Question 34

Describe hallux valgus.

Answer 34

Lateral displacement of the great toe; presents as pain over the prominent metatarsal head

Question 35

Describe hallux varus.

Answer 35

Medial displacement of the great toe