Tibial Plateau

 

Schatzker Classification

 

1.  Lateral Spilt 

- seen in young patient

- lateral meniscus can be incarcerated in fracture

 

Tibial Plateau Schatzker 1

 

2.  Lateral Split Depression

- often seen in young patients with high energy injuries

- vary in severity

 

Tibial Plateau Joint DepressionSchatzker 2 Split DepressionSchatzker 2 Split Depression CT

 

3.  Lateral Depression 

- central depression usually seen in elderly

- have to create lateral cortical window in order to elevate fragment

 

Tibial Plateau Depression

 

4.  Medial plateau & intercondylar eminence 

- high velocity injury associated with ACL / LCL / CPN injury

- can be low injury / osteoporotic and often unreconstructable

 

Schatzker 4 Tibial Plateau

 

5.  Bi-condylar + intact metaphysis

- unstable

- requires ORIF

 

Schatzker 5 Bicondylar0001Schatzker 5 Bicondylar0002Schatzker 5 Bicondylar CT

 

6  Bi-condylar + metaphyseal fracture

- fracture separating metaphysis from diaphysis

- highest incidence of vascular injury

 

Schatzker VISchatzker 6 Schatzker 6 CT

 

Epidemiology

 

Most common is Type II / split depression

- 80%

 

Type IV

- medial plateau involved

- 10 - 20%

 

Type V, VI

- both condyles involved

- 10 - 20%

 

Anatomy

 

Medial plateau larger than lateral

- medial is concave in sagittal plane (golf tee)

- Lateral is convex & more proximal (golf ball)

 

Creates 3o of varus proximal tibia

 

Knee Normal AP

 

Lateral plateau is covered by meniscus

- tolerates incongruity better than medial plateau

 

Normal posterior slope

- 10o

 

Pathology

 

Lateral plateau more commonly fractures

 

1.  Medial plateau more resistant to fracture

- due to its larger surface and increased weight bearing

- thicker stronger subchondral bone

- any fracture of medial plateau indicates high energy 

- high incidence of soft tissue complications & poor outcomes

 

2.  Valgus alignment of leg

 

Type of fracture

 

1.  Young people splits / wedges

2.  Older people joint depression

 

Associated Injures

 

1.  56% incidence of ligamentous instability 

- ACL and LCL seen with medial plateau fracture

 

2.  20% incidence meniscal injury

 

3.  CPN

- again seen with medial plateau fracture

 

4.  Compartment syndrome

- seen in type 5 and 6

 

5.  Popliteal artery damage

 

Factors affecting outcome

 

1.  Step > 5mm

 

Blokker et al Clin Orthop 1984

- >5 mm step 0% G/E

- <5 mm 75% G/E

- < 2 mm 85% G/E

 

2.  Alignment

 

Rasmussen Acta Orthop Scand 1972

- valgus > 10o 80% OA

- valgus < 10o 14% OA

- accept only < 5o varus /  valgus

 

3.  Meniscus

 

Jensen et al JBJS 1990

- 70% OA with meniscectomy

 

4.  Instability

 

Honkonen J Orthop Trauma 1995

- M/L instability > 10o 70% OA

 

Indications for surgery closed fracture

 

1.  Step > 2mm

2.  Malalignment

3.  Mensical injury

4.  ML laxity

 

Management

 

Examination

 

NV examination

Soft tissue examination

- Tscherne / closed soft tissue injury classification

- Gustillo / open soft tissue injury classification

Exclude compartment syndrome

 

CT scan

 

Sssess joint line

- predetermine fracture pattern before fixation

 

Temporary Spanning External Fixation

 

Knee Spanning Ext Fix

 

Tibial Plateau Temporary External Fixator APTibial Plateau Temporary External Fixator Lateral

 

Indications

- open fracture

- complex pattern / shortening / malalignment

- poor soft tissues / extreme swelling

 

Advantages

- pulls out to length with ligamentotaxis

- allows soft tissues to settle / swelling resolves

- subsequent surgery easier and safer

 

Construction

- 2 x 5 mm half pins anterior / AL femur

- 2 x 5mm half pins anterior tibia far from incision

- apply under II guidance / reduce / apply traction

- 2 x anterior rods

- slight flexion

 

Definitive Management

 

1.  ORIF

 

Tibial Plateau ORIF

 

Timing

- blisters epithelialised

- skin wrinkled

- 2-3 weeks

 

Set up

- prone on radiolucent table

- knee flexed over bolster or triangle

- tourniquet, antibiotics

- remove frame, scrub leg and apply sterile dressings to pin sites to remove from operative field

- some surgeons leave frame on to aid reconstructive surgery

- may need to use femoral distractor

 

Approach

 

1. Lateral longitudinal incision

- split ITB proximally

- open anterior fascia distally

- elevate tibialis anterior from tibia

- incise coronary ligament

- elevate capsule and ligament via 1 vicryl stay sutures

- inspect joint and lateral meniscus via varus force

 

2.  Posteromedial approach

- 1 cm from posterior border tibia

- between medial gastrocneumius and pes anserinus

- buttress or antiglide 4 hole DCP / T plate

- may be indicated for Schatzker IV / V / VI

 

Technique

- elevate and restore joint line (may need cortical window and punch)

- compress with bone reduction forcep

- stabilise joint line with 2 x 6.5 mm cannulated partially threaded screws

- check II

- restore alignment via application anatomically contoured 4.5 mm locking plate

- can use MIPO if required (long fracture, Type VI)

- often use BG or substitutes under depression fractures laterally (Norian)

 

Stability

- must assess at end of operation

 

Specific

 

Type 1

- can reduce and screw percutaneously

- beware trapped lateral meniscus

- consider arthroscopic inspection initially

- difficult to see because of haematoma 

- also risk of compartment syndrome so need careful fluid management

 

Tibial Plateau Schatzker 1 Percutaneous ScrewsTibial Plateau Schatzker 1 Percutaneous screws Lateral

 

Posterolateral Tibial Plateau Fractures

- fracture in posterior half of lateral tibial plateau

- very difficult to access / transfibular approach

- expose / release / protect CPN

- predrill fibula head

- osteotomy above CPN

- reflect fibular head posteriorly on biceps / LCL attachments

- ORIF lateral plateua

- fibular osteotomy secured with 6.5 mm partially threaded cancellous screw

 

Type IV

- medial plate alone

- address lateral instability

 

Schatzker 4 Medial Plate0001Schatzker 4 Medial Plate0002

 

Type V

- single lateral plate

- double plating with medial buttress / LCP / T plate

- may wish to reduce lateral side first for anatomy

- apply medial plate second for stability

- may be a coronal split in medial plateau or TT requiring AP screws

- may need ORIF ACL bony avulsion

 

Tibial Plateau Bicondylar ORIF APTibial Plateau Bicondylar ORIF Lateral

 

Tibial Plateau Type VTibial Plateau Type V ORIF APTibial Plateau Type V ORIF Lateral

 

Type VI

- long locking plate minimally invasive with locking jig

- proximal lag screws

- ensure correct alignment

- often use small medial buttress plate

 

Tibial Plateau Schatzker 6 ORIF APTibial Plateau Schtazker 6 ORIF LateralSchatzker 6 ORIF APSchatzker 6 ORIF Lateral.jpg

 

2.  External Fixation

 

Indications

- poor soft tissues

- compound

 

Technique

- pins 14 from joint surface

- use olive wires to compress fracture fragments

 

Schatzker VI Ilizarov

 

Rehabilitation

 

Hinged Brace

NWB 8 weeks minimum

 

Complications

 

Collapse / Malunion

 

Tibial Plateau Collapse Malunion Tibial Plateau Collapse Malunion

 

Tibial Plateau MalunionTibial Plateau Malunion 2

 

Option

 

1. Distal femoral varus osteotomy and fresh osteochondral allograft

 

Lateral Tibial Plateau MalunionValgus MalunionDFVO and osteochondral allograft

 

2. TKR

 

Tibial Plateau OA TKR0001Tibial Plateau OA TKR0002