Knee injuries

Dr Abir Naguib

•Knee pain is the most common musculoskeletal complaint (1/3)

•Source of significant disability

•Most prevalent in physically active individuals

Differential diagnosis of knee pain is extensive

Accurate diagnosis can be achieved by localizing the anatomic site of pain &

patient’s age

•Fracture•Ligament sprain•Tendon rupture•Meniscal tear•Patellar dislocation

Trauma

History1.Pain characteristics:

Onset- location- duration- severity- quality- aggravating and relieving factors

2. Mechanical symptoms:

Pop

Locking

Giving way

5. History of previous injury

3. Effusion:Timing and amount

4. Ability to continue playing

Exclude referred pain (hip injury)

6. Mechanism of injury

Contact (Direction of

blow)

Non-contact(position of knee)

TwistingHyperextension

Deceleration

Non-contact injury

Hyperextension injury

Examination:

Inspection: Swelling (location) Ecchymosis Atrophy

Palpation: Tenderness

ROM

Stability tests

Joint line

Ligament courseActive

passive

Investigations

•RadiologicalX-ray, CT, MRI

•Aspiration(painful swollen joint)Clear yellowBloodBlood + fat droplets

•Arthroscopy

MCL injury

•CO:

Pop at time of injury

Pain , swelling (medial)

•OE:

Tenderness, swelling along ligament course

Valgus stress test

LCL injury

Uncommon

Mechanism: blow to medial aspect knee

Varus force

Similar: (lateral)

Varus stress test

ACL injury

PopImmediate swellingGiving way

Anterior drawer test

Lachman test

ACL

PCL injury

• CO: insecurity of knee

• OE: abrasion on proximal tibia (anterior)

mild swelling posterior drawer test

Posterior sag sign

PCL

Meniscal tear

CO: Pain after quick twisting or squatting

Locking

OE: Swelling

Joint line tenderness

McMurray test

Meniscal tear

Extensor mechanism injury

Quadriceps tendon rupture

Patellar tendon rupture

Patellar instability

Quadriceps tendon ruptureAged, poorly conditioned

(descending,jumping)

CO: severe anterior knee pain

snap

fall suddenly

OE: swelling, tenderness (local)

Palpable gap proximal to patella

inability to extend knee

Quadriceps tendon rupture

Patellar tendon rupture

young athletic patients

eccentric loading of quadriceps

OE: Swelling, tenderness palpable defect at distal pole patella Impaired knee extension

Patellar instabilitySubluxation – Dislocation

Mechanism: direct blow, forceful Q contraction

CO: Buckling Anterior knee painDifficulty extending knee

OE: Swelling (effusion-hemarthrosis) Tenderness medial patella

Apprehension signDD: history & X-ray

Young adults

In almost 90% of knee injuries an accurate diagnosis can be reached through thorough history taking and careful clinical examination.

Thank you