Week 1 Msk Lower Limb

Question 1

What’s avulsion injuries

Answer 1

More common in adolescents involved in sports because the tendons are stronger than apophyses

Question 2

What’s a stress fracture

Answer 2

Plain radiograph could only be positive in less than 10% of cases.
MRI is the gold standard test looking for bone marrow oedema

Question 3

What’s avascular necrosis

Answer 3

This is a condition in which there is a loss of blood supply to the bone. Bone is living tissue, hence loss of blood supply, means bone death. If bone death progresses, leads to bone collapse.
Symptoms may include stiffness in hip, night pain, limp, pain in the groin, buttocks, front of thigh.
The femoral head receives its blood supply through the neck of femur. Fractures across this zone may cause a loss of this supply leading to tissue death.

Question 4

What’s hip dysplasia

Answer 4

Normal center edge angle between 25-40 degrees
<25 - 30 degrees borderline dysplasia
< 20 degrees dysplasia
< 16 degrees will almost certainly develop osteoarthritis

Question 5

What’s labral tears

Answer 5

The majority are not associated with a specific event or cause.
End range motion in position of hyper abduction, hyper extension, hyper flexion, and external rotation contributes to labral tears.
Standard MRI only has 35% sensitivity and accuracy in detecting labral pathology
Sensitivity and accuracy can be improved to reach up to 90% using contrast

Question 6

What’s hip impingement types

Answer 6

2 mechanisms of impingement:

• cam-type FAI
• pincer-type FAI

Question 7

What’s hip impingement (pincer)

Answer 7

Result of excess acetabular coverage of the femoral head.
Over courage can be either global (coxa profunda) or focal anteriorly (acetabular retro version).
Results in abutment of the femoral head neck junction against the acetabular rim pressing upon the labrum.

Question 8

Symptoms for FAI

Answer 8

Sitting cross legged is difficult or painful.
Difficulties putting socks and shoes (52%).
Sitting for a long time(23%) unable to sit for period of time (23%).
Slight or more severe limp (65%).
Adductor related symptoms.
Walking long distance painful and pain doesn’t disappear straight away with rest.
Significant pain after sports activities.
>40% buttock/low back pain

Question 9

What’s greater trochanteric pain syndrome

Answer 9

GTPS is a common cause of lateral hip pain.
Attributable to tendinopathy of gluteus medius and minimus +/- bursae pathology.
Compressive forces cause impingement of these structures onto the greater trochanter by the ITB.

Question 10

What are typical GTPS Paitients

Answer 10

Age 40-60
Female 
Post menopausal 
Lower femoral neck shaft angle 
Increased BMI 
Systemtic factors

Question 11

What’s snapping hip syndrome

Answer 11

AKA Coxa saltans.
Subclassified: (1), internal and external (2)
Internal - caused by iliopsoas over iliopectinal eminence, paralabral cysts.
External - caused by ITB “snapping” over greater trochanter Or proximal hamstring tendon rolling over ischial tuberosity, fascia Altair gluteus maximus over the greater trochanter.

Question 12

What’s osteochondral defect (osteo = bone, chondral = cartilage)

Answer 12

A contralto defect refers to a focal area of damage to the articular cartilage (the cartilage that lines the end of the bones).
An osteochondral defect refers to a focal area of damage that involves both the cartilage and a piece of underlying bone.

Question 13

What’s a subchondral cyst

Answer 13

There’s 2 theories for this:
(A) - the synovial fluid intrusion theory, which proposes that articular surface defects and increased intra-articular pressure allow intrusion of synovial fluid into the bone, Leasing to formation of cavities.
(B) - bone contusion theory, according to which non-communicating cysts arise from subchondral foci of bone necrosis that are the result of opposing articular surfaces coking in contact with each other