Knee Pathologies

Question 1

Knee Joint Components

Answer 1

medial Compartment of the tibiofemoral joint

lateral compartment of the tibiofemoral joint

Patella-femoral Joint

Question 2

Tibiofemoral Joint

Answer 2

Contains fibrocartilaginous menisci

- Act as shock absorbers and act to distribute load evenly

Question 3

Knee Ligaments (4) and function

Answer 3

Anterior Cruciate Ligament (ACL)

• Prevents abnormal internal rotation of the tibia
• Prevents anterior translation of the femur on the tibia

Posterior Cruciate Ligament (PCL)
- Prevents hyperextension and anterior translation of the femur

medial Collateral ligament (MCL)
- Resists valgus force

Lateral Collateral Ligament(LCL)

• Resists varus force
• Resists abnormal external rotation of the tibia

Question 4

OA of the knee: Predisposition

Answer 4

Previous meniscal tears
ligament injuries
malalignment

Question 5

OA of the knee treatment

Answer 5

Young patients with isolated medial compartment OA

• Osteotomy of proximal tibia
• Uni-compartmental knee replacement

Young patients with isolated lateral compartment OA
-Uni-compartmental knee replacement

Patients with substantial pain and disability
- Knee replacement

Question 6

Meniscal Injuries Aetiology

Answer 6

Twisting force on loaded knee

Question 7

Meniscal Injuries Presentation

Answer 7

Localised pain to the joint line
- Medial or lateral

Effusion the following day

Catching or locking sensation

• True knee locking occurs in meniscal tears
• Caused by a significantly torn meniscus flipping over and becoming stuck in the joint line

Feeling of knee giving way

Pain on tibial rotation

Positive Steinmann’s test

Question 8

ACL Ruptures Aetiology

Answer 8

High rotational force

- turning the body laterally on a planted foot

Question 9

ACL ruptures presentation

Answer 9

‘Pop’ sound or feeling

Haemarthrosis and swelling within an hour

Deep knee pain

Rotatory Instability

• with giving way on turning
• main complaint

Excessive anterior translation of tibia on anterior drawer test

Question 10

ACL deficiency

Answer 10

⅓ will compensate well

⅓ will manage by avoiding certain movements

⅓ will do poorly with their knee giving way during normal movements

Question 11

ACL rupture Treatment

Answer 11

Physiotherapy
-Strengthening of quadriceps and hamstrings aid compensation

Patients who cope poorly in day to day activities may require ACL reconstruction
- tendon graft being passed through tibial and femoral tunnels at the usual location of ACL in knee and attachment to bone

May take up to a full year to recover

Question 12

PCL ruptures aetiology

Answer 12

Direct blow to anterior tibia when the knee is flexed

hyperextension

Question 13

PCL rupture treatment

Answer 13

isolated PCl rupture
- Conservative management

Conservative

• only those with severe laxity with frequent hyperextension or feeling unstable when descending stairs are considered for reconstructive surgery
• Use of cadaveric achilles tendon autograft

Question 14

Medial Collateral Ligament tears aetiology

Answer 14

Valgus Stress

Question 15

Medial Collateral Ligament tear Treatment

Answer 15

Usually heals with little or no instability

Acute MCL tears
- Hinged knee brace

Chronic MCL instability

• MCL tighteninh
• Reconstruction with a tendon graft

Question 16

Lateral Collateral Ligament tears aetiology

Answer 16

Varus Stress

hyperextension with various impact

Question 17

Lateral Collateral Ligament tears Consequences

Answer 17

often damage to perineal nerve

Question 18

Lateral Collateral Ligament Tears treatment

Answer 18

Surgical with early repair

Late reconstruction with tendon graft

Question 19

Menisci Blood Supply

Answer 19

Only have arterial blood supply to the outer ⅓

Question 20

Meniscal Tear aetiology

Answer 20

In young patients

• high impact sports
• Acute ACL tears

Question 21

Meniscal Tear Types

Answer 21

Large Longitudinal Tears

Degenerative

Question 22

Large Longitudinal Meniscal Tears

Answer 22

Large bucket handle tears with subsequent knee locking due to the meniscal fragment flipping into the intercondylar notch

Question 23

Degenerative meniscal Tears

Answer 23

Can occur spontaneously or with very little injury

have complex patterns

• Horizontal
• Longitudinal
• Radial components

1st stage in the development of knee OA

Positive Steinmann’s test

Question 24

Meniscal Tears treatment

Answer 24

Repair
-only if fresh longitudinal tears in the outer ⅓ of the meniscus in young patients

Arthroscopic Meniscectomy
- If repair fails

Steroid injections
- Aid symptoms

Arthroscopic Partial Meniscectomy
- In acute cases that don’t settle after 3 months

Question 25

Extensor Tendons

Answer 25

Patellar Tendon

Quadriceps Tendon
- Tends to pull the patella slightly laterally

Question 26

Extensor Tendon Rupture Aetiology

Answer 26

Rapid contractile force
Heavy lifting
Fall
Spontaneous

Question 27

Extensor Tendon Rupture Risk Factors

Answer 27

Tendonitis
Chronic Steroid USe
Diabetes
RA
Chronic renal failure
Use of quinolone antibiotics

Question 28

Extensor Tendon Rupture Investigations

Answer 28

Straight leg raise 
High lying patella 
- Patellar Tendon Rupture 
Low lying patella 
- Quadriceps tendon rupture

Question 29

Extensor Tendon Rupture Treatment

Answer 29

No steroid injections
- due to increased risk of tendon rupture

Surgical tendon to tendon repair

Surgical reattachment of the tendon to the patella

Question 30

Patellofemoral Dysfunction Risk Factors

Answer 30

Female gender
Joint hypermobility
Genu valgum
Femoral Neck anteversion

Question 31

Patellofemoral Dysfunction Presentation

Answer 31

Anterior knee pain 
Grinding or clicking at front of knee 
Pseudolocking
- Only temporal difficulty in straightening the leg 
- Can spontaneously resolve

Question 32

Patellofemoral Dysfunction Treatment

Answer 32

Physiotherapy
Taping
Surgery
- Last resort

Question 33

Patellar Dislocation Direction

Answer 33

Always laterally

Question 34

Patellar Dislocation X-ray appearance

Answer 34

Small Opacification
-Osteochondral fracture due to the medial patellar facet striking the lateral femoral condyle

Lipo-haemarthrosis

Question 35

Patellar Dislocation Risk Factors

Answer 35

Ligamentous Laxity
Female Gender
Shallow trochlear groove
Genu algum 
Femoral neck anteversion 
Patella Alta
- High rising patella

Question 36

Patellar Dislocation Treatment

Answer 36

Physiotherapy

Tibial tubercle transfer