Orthopaedic Knee Conditions

Question 1

What is the aetiology of meniscal tear?

Answer 1

• Acute
  
  • Twisting especially during flexion
• Degenerative
  
  • Osteoarthritis

Question 2

Is medial or lateral meniscal tear more common?

Answer 2

Medial

Question 3

What is the presentation of meniscal tear?

Answer 3

• Symptoms
  
  • Pain
  • Clocking
  • Locking
  • Intermittent swelling
• Signs
  
  • Effusion
  • Tender joint
  • McMurrays test positive
  • Fail deep squat
  • Thassaly’s test position

Question 4

What investigations are done for meniscal tear?

Answer 4

• X-ray
  
  • To exclude arthritis, fracture
• MRI
  
  • Most sensitive test
  • High false positive rate

Question 5

What is the treatment for meniscal tear?

Answer 5

• Unlikely to heal due to poor blood supply
• Non-operative
  
  • Rest
  • NSAIDs
  • Physiotherapy
    
    • Hamstring and quadriceps strengthening
• Operative
  
  • Arthroscopy
    
    • Repair
    • Resection

Question 6

Describe the pathophysiology of OA of the knee?

Answer 6

• Degenerative change of synovial joints
  
  • Progressive loss of articular cartilage
  • Secondary bony changes

Question 7

What is the presentation of OA of the knee?

Answer 7

• Pain and stiffness of joint is characteristic

Question 8

What is the mangement for OA of the knee?

Answer 8

• Conservative
  
  • Weight loss
  • Analgesia
  • Activity modification
  • Braces
  • Walking aids
  • Steroid injection
• Operative
  
  • Total knee replacement
    
    • Cruciate retaining
    • Cruciate sacrificing
  • Uni-compartmental knee replacement
    
    • Medial (most common)
    • Lateral
    • Patello-femoral

Question 9

Describe the anatomy of the ACT in terms of where it runs between, blood supply and innervation?

Answer 9

• Runs between tibial eminences to lateral wall of intercondylar notch of femur
• Blood supply is middle geniculate artery
• Innervation is posterior articular nerve (branch of tibial nerve)

Question 10

What is the blood supply of the ACT?

Answer 10

Middle genticulate artery

Question 11

What is the innvervation of the ACT?

Answer 11

Posterior articular nerve (branch of tibial nerve)

Question 12

What is the function of the ACT?

Answer 12

• Primary restrain to anterior translation of tibia relative to femur
  
  • Secondary restraint to tibial rotation and vargus/valgus stress

Question 13

What is the aetiology of ACT injury?

Answer 13

• Non-contact pivot injury

Question 14

Describe the epidemiology of ACT injury in terms of sex?

Answer 14

• F:M 4.5:1

Question 15

What is the presentation of ACT injury?

Answer 15

• Heard a pop or crack
• Immediate swelling (70%)
• Unable to continue playing
• Deep pain
• Signs
  
  • Effusion
  • Anterior draw test positive
  • Lachmann’s test positive
  • Pivot shift test positive

Question 16

What investigations are done for ACT injury?

Answer 16

• X-ray
  
  • Secondary fracture
• MRI
  
  • Look at ACL
  • Look at menisci
    
    • Lateral tear simultaneous with ACL tear half the time
    • Medial tear occurs secondary to chronic instability

Question 17

What is the treatment for ACT injury?

Answer 17

• Non-operative
  
  • Focused quadriceps programme
• Operative
  
  • ACL reconstruction

Question 18

What are the functions of the superficial and deep MCL?

Answer 18

• Superficial
  
  • Primary restrain to vulgus stress
• Deep
  
  • Contributes in full knee extension
  • Attaches to medial meniscus, continuous with joint capsule

Question 19

What is the presentation of MCL injury?

Answer 19

• Heard a pop or crack
• Pain
  
  • Medial side
• Unable to continue playing
• Bruising medial knee
• Localised swelling

Question 20

What investigations are done for MCL injury?

Answer 20

• X-ray
• MRI
  
  • Modality of choice
  • Assess location and severity of injury

Question 21

What is the treatment for MCL injury?

Answer 21

• Non-operative
  
  • Majority of treatment
  • Rest
  • NSAIDs
  • Analgesia
  • Physiotherapy
  • Brace
• Operative
  
  • For severe tears when non-operative management has failed
  • Repair or reconstruction
    
    • Repair – avulstions
    • Reconstruction – damaged tissue

Question 22

What is osteochondritis dissecans?

Answer 22

Pathological lesion affecting articular cartilage and subchondral bone

Question 23

What are the 2 forms of osteochondritis dissecans?

Answer 23

• Juvenile
  
  • 10-15 years while growth plates still open
• Adult

Question 24

What is the aetiology of osteochondritis dissecans?

Answer 24

• Hereditary
• Traumatic
• Vascular
  
  • Adult form

Question 25

What is the most common location of osteochondritis dissecans?

Answer 25

* Knee most common location * Posteriolateral aspect of medial femoral condyle

Question 26

What is the presentation of osteochondritis dissecans?

Answer 26

* Activity related pain * Poorly localised * Recurrent effusions * Mechanical symptoms * Locking * Block to full movement

Question 27

What investigations are done for osteochondritis dissecans?

Answer 27

* X-ray * Add in tunnel view (flexed 30-50^o) * MRI * Lesion size * Status of cartilage and subchondral bone

Question 28

What is the treatment of osteochonditis dissecans?

Answer 28

* Non-operative * Restricted weight-bearing * ROM brace * Operative * Arthroscopy * Subchondral drilling * Fixation of loose fragments * Open fixation