Knee Problems

Question 1

What is the differential diagnosis for a knee problem?

Answer 1

• Fracture
• Acute on chronic degenerative joint disease
• Meniscal injury
• Ligament injury
• Tendon injury

Question 2

What history should you collect for a knee problem?

Answer 2

Environment

• Sport or recreation
• Workplace

Activity: sports, tackles, jumping

Energy
-How fast, how heavy

Systemic symptoms

Chronology and Event

• Quick or slow onset
• Previous injury or event
• Hear or feel pop or crack
• Swelling (early (haemarthrosis) or late onset)

Question 3

How do meniscal injuries occur?

Answer 3

Twisting movement on a loaded fixed knee

Question 4

How do meniscal injuries present?

Answer 4

• Painful ‘squelch’
• Slow swelling (quicker in the younger)
• Painful to weight bear
• Locked knee

Question 5

How do ACL tears occur?

Answer 5

Forward momentum with a fixed leg +/- rotation

Question 6

How do ACL tears present?

Answer 6

• ‘Pop’
• Quick swelling
• Often able to weight bear

Question 7

How do collateral tears present?

Answer 7

• Lateralised pain
• Feel of ‘crack’ with sharp pain
• No or minimal effusion
• Bruising to one side

Question 8

What examination should be carried out on the knee?

Answer 8

Look

• Scars, bruising and swelling
• Joint line irregularity

Feel

• Effusion
• Crepitus
• Heat
• Tenderness
• Tissue lumps or defects

Move: passive and active

• Straight leg raise
• Range of movement
• Ligament testing
• Dynamic testing

Question 9

What can be seen on x-rays of knee problems?

Answer 9

• Fractures
• Loose bodies
• Ligament avulsions
• Osteochondral defect
• Degenerative joint disease
• Lipohaemarthrosis

Question 10

What can be seen on ultrasound of knee problems?

Answer 10

• Tendon rupture
• Some meniscal tears
• Swelling
• Cysts

Question 11

What are MRI scans used for?

Answer 11

• Clinical confirmation

- They have variable sensitivity and specificity but the are not good for DJD or mobile pathology

Question 12

What is surgery used for in knees?

Answer 12

• Joint preservation

- Life-long care of the joint

Question 13

What are the indications for surgery in knee problems?

Answer 13

• Failure of conservative treatment
• Demands of work
• Demands of sport
• Problems with daily activities
• Prevention of further joint injury
• Prevention of falls

Question 14

What non-surgical options are there for treatment of knee problems?

Answer 14

• Restoration of function
• Physiotherapy
• Analgesia
• Swelling reduction
• Range of motion
• Normal movement

Question 15

How can meniscal injuries be treated?

Answer 15

• Meniscal repair
• Partial meniscectomy
• Meniscal transplantation

Question 16

Describe the structure of the menisci.

Answer 16

• Medial semi-circular
• Lateral almost circular
• Fibro and chondroblasts in matrix of type 1 collagen
• Radial (tie) and circumferential (hoop) fibres
• Superficial randomly orientated fibres

Question 17

How are loads transmitted through the menisci?

Answer 17

Radial component of the loading force is balanced by tensile stresses developed in the circumferentially orientated collagen fibres

Question 18

Describe the vascular anatomy of the menisci.

Answer 18

• Perimeniscal capillary plexus originates from branches of the inferior medial and lateral geniculate arteries
• Perimeniscal plexus forms circumferential vessels and penetrating radial vessels

Question 19

Who gets meniscal repairs?

Answer 19

• Young
• Sporty
• Fresh tears (up to 3 months)
• healthy meniscus
• Red/red or red/white

Question 20

What repair techniques can be used for meniscal injuries?

Answer 20

• Open technique
• Outside-in
• Inside-out
• All inside
• Smith and Nephew

Question 21

What is the Smith and Nephew technique for meniscal repair?

Answer 21

• Device is passed through portal and through meniscus to a depth that enables ‘T’ to be deployed
• Once ‘T’s are deployed, knots are tied outside joint and a know pusher is used to slide knots snuggly against the meniscus

Question 22

What is the prognosis of meniscal repairs?

Answer 22

• 90% success roughly
• 1:5 fail/ need re-arthroscopy and probable partial meniscectomy
• 1:5 fail at re-scope/MRI

Question 23

How are ACL injuries managed?

Answer 23

• Full ACL rehabilitation
• ACL reconstruction
• Often concomitant other injuries

Question 24

Why may someone undergo surgery for an ACL tear?

Answer 24

• Prevention of further injury
• Back to work
• Back to sport
• Prevention of osteoarthritis

Question 25

What are the treatment options for osteochondral injuries?

Answer 25

- Debridement - Reattachment of fragment - Removal of bodies - Microfracture chondroplasty - ACI