Tibial Plateau Fracture
Summary
Tibial Plateau fractures are complex intra-articular injuries of the proximal tibia, accounting for 1% of all fractures. They result from a combination of Axial Loading (Hammer) and Varus/Valgus force (Chisel). The injury pattern is bimodal: High-energy trauma (Falls/MVA) in young patients, and low-energy falls in osteoporotic elderly. The gold standard for classification is the Schatzker System (I-VI). Management is strictly dictated by the condition of the soft tissues ("The Envelope"). High-energy fractures (Schatzker V/VI) are soft tissue emergencies requiring immediate spanning external fixation ("Span, Scan, Plan") until the swelling settles (Wrinkle Sign). Low-energy fractures may be treated with plates/screws or non-operatively if non-displaced. [1,2,3]
Key Facts
- Most Common: Lateral Plateau (Schatzker II) fractures accounts for 55-70% because the physiologic valgus of the knee predisposes the lateral side to loading.
- Soft Tissue Envelope: The proximal tibia has very thin subcutaneous tissue. Wound breakdown exposes the plate and bone, leading to osteomyelitis.
- Lipohemarthrosis: A fat-fluid level on the lateral X-ray (marrow fat floating on blood). This is pathognomonic for an intra-articular fracture even if the fracture line is invisible.
- Meniscal Tears: Occur in 50% of plateau fractures (usually on the side of the fracture).
Clinical Pearls
"Span, Scan, Plan": For high-energy fractures (Schatzker V/VI), the mantra is:
- Span: Apply a knee-spanning external fixator in ED/Theatre to restore length and ligamentous taxis.
- Scan: Get a CT scan to map the articular fragments.
- Plan: Wait 10-14 days for the "Wrinkle Sign" (resolution of edema) before performing ORIF.
"Beware the Medial Fracture": Schatzker IV (Medial Plateau) requires high energy (Varus force) and is the fracture of "Dislocation". It has the highest rate of Neurovascular injury.
"The Rafting Screw": Modern plates use a row of screws immediately under the cartilage, acting like a raft to support the depressed joint surface like a floor joist.
Demographics
- Incidence: 10 per 100,000.
- Age: Bimodal.
- Young Males: High energy (Motorbike, Fall from height).
- Elderly Females: Low energy (Osteoporosis + Valgus force).
- Mechanism:
- Axial Load: Drives the femoral condyle into the tibia.
- Bumper Injury: Pedestrian struck from the side (Valgus force = Lateral plateau).
Anatomy
- Lateral Plateau: Convex shape. Located higher than the medial side. Weaker trabecular bone (fractures easily).
- Medial Plateau: Concave shape. Stronger bone (requires higher energy to break).
- Soft Tissues:
- Menisci: The lateral meniscus covers a larger portion of the plateau. Tears are common (50%).
- ACL: 10-25% association (Avulsion of tibial spine).
- MCL: Associated with lateral plateau # (Valgus stress).
- LCL/PLC: Associated with medial plateau # (Varus stress).
Schatzker Classification (The Gold Standard)
Based on AP X-ray appearance.
- Type I: Lateral Wedge (Split). Pure cleavage. Occurs in young bone (resists depression).
- Type II: Lateral Split + Depression. Most common. Occurs in older bone (cortex splits, cancellous bone crushes).
- Type III: Lateral Pure Depression. Osteoporotic. Lateral cortex intact.
- Type IV: Medial Plateau. High energy. Often involves intercondylar eminence. Neurovascular risk.
- Type V: Bicondylar (Both plateaus). The shaft is intact but the condyles are split (Inverted 'Y').
- Type VI: Bicondylar with Metaphyseal Dissociation. The articular block is separated from the shaft. Massive soft tissue injury.
Three Column Concept (Luo)
Modern classification for CT planning.
- Lateral Column.
- Medial Column.
- Posterior Column: Not visible on AP X-ray. Requires a specific posterior approach (Posteriolateral or Posteromedial) to fix.
Symptoms
Signs
Compartment Syndrome Assessment
Imaging
- X-Ray (4 Views):
- AP: Standard.
- Lateral: With beam tilted 10 degrees caudal (plateau slope). Look for Lipohemarthrosis.
- Internal/External Oblique: Assessing depression.
- CT Scan (Mandatory): Essential for operative planning.
- Quantifies depression (mm).
- Shows posterior column fractures (invisible on AP).
- MRI: Useful for ligament/meniscal assessment, but hardware degrades the image. Usually done later if instability persists.
Vascular Studies
- ABI (Ankle Brachial Index): If <0.9, needs CT Angiogram.
- CTA: Mandatory for Schatzker IV/VI with asymmetric pulses.
TIBIAL PLATEAU FRACTURE
↓
IS IT HIGH ENERGY?
(Schatzker V/VI, Tense Swelling)
┌────────────┴─────────────┐
NO YES
(Schatzker I-III) (Schatzker IV-VI)
↓ ↓
ARTICULAR STEP >2mm? **DAMAGE CONTROL**
OR UNSTABLE >10 deg? - Spanning Ex-Fix
↓ - CT Scan
┌─────┴─────┐ - Watch for Compartments
NO YES - Wait for Swelling
↓ ↓ ↓
CONSERVATIVE ORIF STAGED ORIF
(Hinge Brace) (Plates) (When skin wrinkles)
Indications
- Non-displaced fractures.
- Step-off <2mm.
- Stable in extension/flexion (Varus/Valgus stress test negative).
- Non-ambulatory patient (Dementia/Bedbound).
Protocol
- Hinged Knee Brace: Locked 0-30 degrees for 2 weeks, then opened.
- Weight Bearing: Non-Weight Bearing (NWB) or Touch-Weight Bearing (10kg) for 6-10 weeks. Cartilage heals poorly under shear load.
- Follow-Up: X-Ray at 1, 2, 6 weeks. If displacement occurs -> Surgery.
Indications for Surgery
- Articular step-off >3mm.
- Condylar widening >5mm.
- Valgus/Varus instability >10 degrees.
- Open fracture.
- Compartment syndrome (Fasciotomy + fixation).
Techniques
- Percutaneous Screws: For simple split (Type I). Two cannulated screws usually suffice.
- ORIF (Plate & Screws):
- Lateral Buttress Plate: Anti-glide plate for Type II. Prevents the condyle sliding down.
- Bone Graft / Substitute: The depressed fragments are punched UP. This leaves a void (hole) in the metaphysis. Must be filled with graft (Autograft or Calcium Phosphate cement) to prevent re-collapse.
- Rafting Screws: Subchondral screws supporting the joint.
- Dual Plating: Medial and Lateral plates for Bicondylar fractures (Type V/VI). Requires two incisions (Midline incision is DANGEROUS - massive skin necrosis).
- Fine Wire Frame (Ilizarov/Taylor Spatial Frame): For severe soft tissue compromise. Pins distant from the fracture. Allows early weight bearing.
Early
- Compartment Syndrome: High risk in Type VI and high-velocity injuries.
- Wound Dehiscence: If operated too early through swollen skin. Leads to exposed metalwork.
- Infection: Deep infection (1-5%). Catastrophic. Requires removal of hardware, debridement, antibiotic cement beads, and Ex-Fix.
- DVT/PE: High risk.
Late
- Post-Traumatic Osteoarthritis: Risk correlates with articular reduction quality and initial cartilage damage ("The die is cast at the moment of impact").
- Stiffness: Arthrofibrosis.
- Malunion: Valgus collapse.
- Non-Union: Rare in metaphyseal bone.
The "Wrinkle Sign"
- Operating through oedematous skin increases infection risk by 10x.
- Wait until skin wrinkles appear (usually 10-21 days). The fracture is "sticky" (early callus) but reducible.
Associated Injuries (Gardner et al)
- Schatzker II: 10% Meniscal Tear.
- Schatzker IV: 30% ACL/PCL/PLC injury.
- Always examine the ligaments under anaesthesia (EUA).
SPRINT Trial
- Wait for soft tissues.
What is the Tibial Plateau?
It is the flat top of your shin bone that forms the knee joint. It is like a table top. If it breaks, the table surface becomes uneven (like a cracked pavement).
Why is it serious?
Because it is a weight-bearing joint. If the "pavement" heals unevenly, the cartilage (tyres) will wear out very quickly, leading to severe arthritis.
The Plan (Span-Scan-Plan)
Your leg is too swollen to operate on safely today. The skin is like wet tissue paper. If we cut it now, the wound will open up and the metal will get infected. We will put a temporary metal frame (Ex-Fix) on the outside of your leg to hold the bones out to length. In 2 weeks, when the swelling goes down and the skin wrinkles, we will do the final surgery with plates and screws.
Recovery
- No walking: You cannot put weight on this leg for 3 months. The bone needs to heal perfectly.
- Movement: We will start bending the knee early to stop it getting stiff.
- Schatzker J, et al. The tibial plateau fracture. The Toronto experience 1968--1975. Clin Orthop Relat Res. 1979.
- Egol KA, et al. Staged management of high-energy proximal tibia fractures (OTA types 41). J Orthop Trauma. 2005.
- Berkson EM, et al. High-energy tibial plateau fractures. J Am Acad Orthop Surg. 2006.
Q1: What are the 6 types of Schatzker fractures? A:
- I: Split (Lat).
- II: Split + Depression (Lat).
- III: Depression (Lat).
- IV: Medial (Bad - High Energy).
- V: Bicondylar (Inverted Y).
- VI: Metaphyseal Dissociation.
Q2: What is "Lipohemarthrosis"? A: A fat-fluid level seen on a lateral knee X-ray (shoot-through) in the suprapatellar pouch. It indicates marrow fat has escaped into the joint, confirming an intra-articular fracture lateral to the capsule.
Q3: Describe the "Rafting Screw" concept. A: Using a row of parallel screws immediately bone the articular cartilage (subchondral) to support the reduced joint surface and prevent subsidence, similar to rafters supporting a roof.
Q4: Why avoid a single midline incision for bicondylar fractures? A: It raises large skin flaps which devascularize the soft tissues over the tibia, leading to massive wound necrosis. Two separate incisions (Anterolateral and Posteromedial) maintain a skin bridge of >7cm, preserving the vascularity.
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