KNEE INJURIES

Question 1

DDX

Answer 1

FRACTURE / DISLOCATION

Knee Dislocation

Patellar Dislocation

DISTAL FEMUR FRACTURE
Supracondylar
Intercondylar
Condylar
Distal Femoral Epiphyseal

PROXIMAL TIBIA FRACTURE
(at or above the tuberosity)
Tibial Plateau
Tibeal Spine
Tibial Tuberosity
Tibial Epiphyseal (children)
Tibial subcondylar

Patellar Fracture

Fibular Head Fracture

SOFT TISSUE

Meniscus Injury

Question 2

DOCUMENTATION

Answer 2

HISTORY

1. Mechanism
2. Timing: Onset of Pain
3. Ability to Ambulate

PHYSICAL EXAM

4. Inspection
   -ecchymosis, effusion, and deformity.
   -Note leg shortening and external rotation of the femoral shaft.
   -varus or valgus deformity.
   -Assess for open fracture:
5. Palpate
   -Patella
   -Tibeal Plateau
   -Fibular Head
   -Femoral / Patellar Tendon
   -Knee effusion
   -Popliteal space for hematoma
6. ROM
   Note maximum range
7. Straight Leg Raise: Assess Extensor Mechanism
8. Check Pulses
   Popliteal artery
   Popliteal pulse
   Distal Pulse
   ABI if concern
9. Neurological Exam
   Drop Foot (peroneal n.)
   Web Space between first and second toe (peroneal n. )

INVESTIGATIONS

10. OTTAWA ANKLE RULES
    X-ray is recommended for patients with knee trauma and the following:
    Age >55 y
    Isolated tenderness to patella*
    Unable to flex to 90°
    Tenderness at head of fibula
    Unable to bear weight both immediately after injury and in the ED (4 steps)**
    Clinically significant fracture can be ruled out with pooled sensitivity and specificity of 98.5% and 48.6%, respectively.

If used, these rules reduce knee X-ray by 25%-50%

11. XRAY: INTERPRETATION
    AP, Lateral, Oblique +/- Sunrise

Check AP, Lateral, Oblique: TAB
-Tibial Plateau & Spines
-Alignment
-Bones

Sunrise View: Patellar Fracture

12. CT KNEE:
    concerns for occult fracture not visible on X-rays, nonunion, or malunion.
    CT/MRI can be used to assess for associated tendon and ligament injuries.
13. CTA
    -if abnormal ABI OR signs of arterial insufficiency

Question 3

MANAGEMENT: TIBIAL PLATEAU

Answer 3

CLASSIFICATION
Schatzker I: Lateral plateau split fracture
Schatzker II: Lateral plateau split-depressed fracture
Schatzker III: Lateral plateau pure depressed fracture
Schatzker IV: Medial plateau fracture
Schatzker V: Bicondylar plateau fracture
Schatzker VI: Metaphyseal-diaphyseal dissociation

NON OPERATIVE

Knee Immobilizer
Non Weight Bearing

Can be managed non-operatively if all criteria are met:
No (or minimal) displacement
Not comminuted comminuted fractures
No depression of the tibial plateau
No ligamentous or meniscal injury

Document NV status before and after spint

ADMISSION

Orthopedic Consultation:

distal femur
neurovascular compromise
compartment syndrome
open fractures

COMPLICATIONS:
High Risk of Compartment Syndrome (11%)
Fibular Head Fracture (30%)
Ligamentous Injuries (up to 66% of cases)

Question 4

MANAGEMENT: PATELLAR FRACTURE

Answer 4

MANAGEMENT: NON OPERATIVE
Intact extensor mechanism
Minimally displaced / non-displaced
<2 mm of step-off
<3 mm of fracture displacement
knee immobilizer, in extension
Rest
Ice
ortho follow-up in ~1 week

MANAGEMENT: OPERATIVE
Open
Communuted
NV Compromise
Avulsion
> 2 mm articular step-off
> 3 mm fractment separation
Disruption of extensor mechanism
Knee Immobilizer
Rest
Ice
Analgesia
Referral to Ortho from ED