Common disorders of the knee Flashcards
What are common disorders of the knee
Menisacal tear Osteoarthritis ACL injury MCL Osteochondritis Dissecans
What causes an acute meniscal tear
Twisting esp in deep flexion
What causes degenerative meniscal tear
Osteoarthritis
What meniscus is more likely to tear and why
Medial meniscal tears more common because it’s a more fixed structure
Symptoms of Meniscal tear
Pain
Clicking
Locking
Intermittent swelling
Examination of Meniscal tear
Look - effusion Feel - Tender joint line at point of tear (esp medial tear) Move - Mechanical block to movement - McMurrays test positive - Fail deep squat - Thassaly’s test positive
Investigations of Meniscal tear
Investigations
X-ray - Arthritis - Fracture Mri - Most sensitive test - High False positive rate
Treatment of Meniscal tear Prognosis
Unlikely to heal as poor blood supply
Non-operative treatment of Meniscal tear
Rest
Nsaids
Physiotherapy
Operative treatment of Meniscal tear
Arthroscopy
¥ Repair
¥ resection
What typically causes ACL injury
Non-contact pivot injury
Presentation of ACL injury
Heard a ‘pop’ or ‘crack’ Immediate swelling (70%)
haemarthrosis
Unable to continue playing
Can walk in straight line
Deep pain
Examination of ACL injury
Look
¥ Effusion (if recent injury)
Feel
Move ¥ Anterior draw ¥ Lachmann’s test ¥ Pivot shift ¥ Best done under anaesthetic
Investigations of ACL injury
X-ray
- Segond fracture
o Avulsion # of anterolateral ligament
Mri
- Acl
- Meniscii
o Lateral – simultaneous with acl tear (48%)
o Medial – secondary to shear from chronic instability
Non-operative of ACL injury
- Focussed quadricep programme
operative of ACL injury
- Acl reconstruction
o +/- partial menisectomy +/- ligament repair or augmentation
o Hamstring graft
What is most common common ligament injury of the knee
MCL tear/rupture
What causes MCL tear/rupture
Severe valgus stress
- Usually contact-related
What is presentation of MCL rupture
¥ Heard a ‘pop’ or ‘crack’ ¥ Pain ++ ¥ Medial side ¥ Unable to continue playing ¥ Bruising medial knee ¥ Localised swelling
Examination
¥ Look ¥ Medial swelling ¥ bruising ¥ Feel ¥ Tender medial joint line ¥ Tender femoral insertion of mcl ¥ Move ¥ Painful in full extension ¥ Opening on valgus stress
Imaging
¥ X-ray ¥ May be normal ¥ Calcification at femoral insertion (Pellegrini-stieda) ¥ Chronic injury ¥ Mri ¥ Modality of choice ¥ Assess location and severity of injury ¥ Identify other pathologies
Non-operative treatment
¥ Majority
¥ Rest, nsaids
¥ Physiotherapy
¥ Brace for comfort
operative treatment
¥ Severe tears ¥ Failed non-operative management ¥ Repair or reconstruction ¥ Repair: avulsions midsubstance tear with good tissue ¥ Reconstruction: damaged tissue
What is Osteochondritis Dissecans
Pathological lesion affecting articular cartilage and subchondral bone
How is Osteochondritis Dissecans categorised
Juvenile
adult
Aetiology of Osteochondritis Dissecans
Hereditary
Traumatic
Vascular
- Adult form
Presentation of Osteochondritis Dissecans
Activity-related Pain
- Poorly localised
Recurrent effusions
Mechanical symptoms
- Locking
- block to full movement
Examination of Osteochondritis Dissecans
May be normal
Look
- effusion
Feel
- Localised tenderness
Move
- stiffness
- Block to movement
- Wilson’s test
Investigations of Osteochondritis Dissecans
X-ray
- Add in tunnel view (flexed 30-50 deg)
MRI
- Lesion size
- Status of cartilage and subchondral bone
- Signal intensity
- Oedema suggests instability of fraglment
Non-operative treatment Osteochondritis Dissecans
Restricted weight-bearing
Rom brace
Operative treatment of Osteochondritis Dissecans
Arthroscopy
- Subchondral drilling
- Fixation of loose fragment
Open fixation
Where is most common location of Osteochondritis Dissecans
Knee = most common
Posterolateral aspect of medial femoral condyle (70%)
