Proximal Tibial Fractures

Kai-Cheng Lin高雄榮總骨科部 林楷城

103/08/16台中榮總

台灣骨科創傷醫學會 103年度住院醫師研習課程

Outlines

• Anatomy• Mechanism of Injury• Examination/Evaluation• Classifications• Surgical Indications• Case Examples• Complications

Anatomy of the Tibial Plateau

• Proximal Tibia– Made up of medial and lateral plateau

or condyles– Bony prominences (attachments)

• Intercondylar eminence (ACL)• Tibial tubercle (Patellar Tendon)• Gerdy’s tubercle (ITB)

– Joints• Knee joint (Distal Femur/Patella)• Proximal tib/fib joint

Anatomy of the Tibial Plateau

• Medial Plateau – Concave– Larger– Cartilage thick ~ 3 mm– Posterior slope of 10°

• Lateral Plateau– Convex– Higher on lateral view– Larger meniscus – Cartilage thick ~ 4 mm– Posterior slope of 7°

MCL, ACL, LCL, Popliteal artery, peroneal nerve are all potentially at risk for injury

Meniscus

• Lateral meniscus– More circular than

medial– Covers more of articular

surface than medial– Attached to PCL via

ligaments• Humphry (anterior)• Wrisberg (posterior)

– No attachment to LCL– Bears more joint

reactive force

• Medial meniscus– “C” shaped– intimately attached to

MCL– bears equal joint

reactive force as boneLateral meniscuc is vulnerable to injury after trauma

Mechanisms of InjuryThe first consideration: a low- or high-energy mechanism– Low-energy: a fall from a standing height– High-energy: Motorcycle or motor vehicle collisions

Fracture-dislocations, involvement of the medial tibial plateau, and metaphyseal comminution

Evaluation

• Prior to evaluating the injured limb, a thorough trauma evaluation should be performed• Many tibial plateau fractures occur in multiply injured patients, and ATLS protocols must be initiated in this setting• Visual inspection: soft-tissue swelling, open lacerations, and limb deformity• Complete neurologic examination- Common peroneal nerve: at particular risk for injury due to close to the fibular neck

Evaluation

• Can be associated with a knee dislocation, especially with medial tibial plateau frx→ vascular examination is critical– distal pulse palpation, assessment of the color and temperature of the foot, and obtaining ankle-brachial indices (ABI)– An (ABI) <0.9 warrants more invasive vascular studies

Soft-tissue status

significant and clinically, relevant information

-- fracture blisters-- non-wrinkling skin-- open lacerations-- tense compartments-- ecchymosis is present

Bony injury is static and the soft-tissue injury is dynamic and can evolve

水泡 Vs 血泡

Compartment syndrome -> fasciotomy

Clinical Diagnosis No Hesitate if Doubt

Radiographic Evaluation

• AP, Lateral (Including two joints)• Obliques (optional)

– Internal rotation view– Shows postero-lateral fragment

• Traction Films (better joint interpretation)– Defines fragments– Bridging Ex-fix can provide traction

• CT scan with reconstruction– Obtain after ex fix if using– Axial– Coronal– Sagittal

• Arteriography when necessary (or check ABI > 0.9)• MRI – unsuspected fxs or soft tissue injury

小心

Tibial segmental fracture要注意上下關節

Traction view

Soft Tissue Injury on MRI

Cruciates ACL 57%PCL 28%

Collateral LCL 29%MCL 32%

Posterolateral corner 68%

Menisci Lateral 91%Medial 44%

Gardner MJ et al. The incidence of soft tissue injury in operative tibial plateau fractures: a magnetic resonance imaging analysis of 103 patients. J Orthop Trauma 2005;19:79-84

103 acute TPFs

The lateral collateral ligament (fibular collateral

ligament)

Urgent and Provisional Treatments

Cross knee Ex-Fix: 2 Schanz half pins in femur & 2 pins in tibia

Connected with multiple clamps and bars in the region of the knee

Avoid placing the clamp directly over the knee to allow radiographic visualization

Tibial pins should be distal enough to avoid interference with the definitive incisions and implantsJoint over-distraction may be detrimental to neurovascular structures

Temporary External Fixation

Femur

Anterior or Antero-Lateral

Tibia

Medial or Antero-Medial

Draw Operative Incisions

Place Outside Area of Injury

Operative tactics—spanning external fixation

• Restores and maintains length

• Restores axial alignment of leg

• Improves position of bone fragments by ligamentotaxis

• Reduces further soft-tissue embarrassment

• Allows outpatient treatment

Fracture classification OTA

Type AExtraarticular

Type BPartial articular

Type CComplete articular

x(Schatzker I−IV)

(Schatzker V−VI)

41-A1 41-A2 41-A3

41-B1 41-B2 41-B3

41-C1 41-C2 41-C3

Fracture classification—Schatzker

partial articular fractures complete articular fractures

Type I Type II Type III Type IV Type V Type VI

Low energy trauma High energy trauma

3-Column concept

3D CT

3-Column classification

• Column fracture—breakage of corresponding cortex (compression/tension fracture)

• Localize the articular surface

depression—approach to reduce

• Pure depression of articular surface (Schatzker type III)—“zero column fracture”

Indications of Non OpStable to varus and valgus stressNot affect the coronal plane limb alignmentMinimal articular displacementNonambulatory or medically unstable

patients should be considered for nonsurgical treatment

The importance of early joint motion to minimize stiffness and improve the nutrition and health of he injured cartilage has been stressed

Key points of TPFs

Meniscal preservation is critical for long-term joint maintenance

A recent large series of bicondylar tibial plateau fractures: more accurate articular reconstruction improved functional outcomes

-Laboratory data: 1.5 mm of incongruity of the lateral tibial

plateau, the contact stresses on the adjacent cartilage are

approximately doubled-A threshold of 2 mm of articular step-off is used for surgical indications and for intraoperative reductions

Surgical Goals of TPF• Obtain/Secure Articular

Reduction• Reduce Condylar Width• Restore Axial Alignment• Neutralize Meta-

Diaphysis• Early ROM• Appropriate Soft Tissue

Handling

Direct VisualizationArthroscopic aid

Radiographically

Medial/Lateral PlatesLateral Plate/Medial ExFixLateral Fixed-Angle Plate

External FixationHybrid

Reduce Joint DepressionReserve MeniscusRestore AlignmentRepair Ligamentous Stability

A new way of thinking

Morphology + injury mechanism

Varus + extension

Valgus + extension

Flexion

Principles for approach selection

• Biomechanical fixation

• Touch of depressed articular fragment

• Soft tissue tolerance

Principle for plate fixation

• Buttress fixation is preferred for column fractures

• Main buttress plate is chosen according to the injury mechanism

• Bridging is used for comminuted metaphyseal fractures

Surgical Approaches

• Straight Midline• Lateral Parapatellar• Medial Parapatellar• Posteromedial• Posterior• Dual approaches for bicondylar fractures

• AVOID Mercedes incision or midline with stripping of soft tissues, especially for bicondylar fractures

Approaches

Anterolateral Posteromedial

Anterolateral approach

Check Meniscus

Partial articular fractures

Schatzkertype I

Schatzkertype II

Schatzkertype III

Schatzkertype IV

Schatzker type I

• Split fracture

• Open vs percutaneous treatment

• Lag screws+/- buttress plate

Schatzker type II

• Split depression fracture

• Submeniscal arthrotomy

• Elevation/bone graft

• Lag screws/buttress plate

Schatzker III

• Pure depression fracture

• Amenable to percutaneous techniques with fluoroscopy +/- arthroscopy

• Metaphyseal window for elevation and grafting

• Screws beneath subchondral bone

Schatzker III

Elevate the depressed central fragment from below

Type III Depression—preoperative

31-year-old

CT—articular depression

Arthroscopic Reduction IF

medial depression fragment elevation

Fixation Lateral Plateau Fractures

• Traditional– large fragment “L” or “T ” buttress plate– 6.5mm subchondral lag screws– 4.5mm diaphyseal screw

• Current Recommendation– small fragment fixation– pre-contoured peri-articular plates– clustered sudchondral k-wires– “rafting”

Raft Screws

BiomechanicsSubchondral Fixation

• 3.5 mm raft construct allowed significantly less displacement than 6.5 mm screw with axial load

(2954 vs. 968 newtons/mm) Twaddle et al AAOS, 1997

• No difference in pull out strength between 6.5mm screws and 3.5mm screws in subchondral bone Westmoreland et al J Ortho Trauma 2002

• Subchondral clustered K-wires significantly enhance load tolerance to depression of articular surface Beris et al Bull Hosp Joint Dis 1996

Schatzker type IV

• Medial tibial plateau fracture

• Frequently realigned knee dislocations

• Associated with:

-Peroneal nerve injury 5 − 50%

-Popliteal artery injury 13 − 50%

Reduction

Schatzker type IV—Medial columnExtension varus mechanism

Schatzker type IV—Medial column

Extension varus mechanism

Submuscular Plating

Schatzker type IV— Medial column + PM

Flexion varus mechanism Fracture dislocation

• The result of ORIF for this type of injury is not satisfactory

Supine Approach:

midline + posteriomedial

Midline approach

Posteriomedial approach

Fracture window

Prone Approach: posteromedial + MIPO

medial Inverted L incision

Post Op

Supine PM approach

1. Concomitantly manage displaced articular fractures of the lateral tibial plateau

2. Simplification of patient positioning for those patients with associated injuries of the head, chest, abdomen, spine, and pelvis

3. But, extensive dissection for reduction and fixation of posteromedial fragment

Prone (Lobenhoffer)/Combined approach

1. Direct reduction of depressed posterior compartment joint line

2. Biomechanical advantages of stabilization of PM fracture

3. Simplified insertion of screws for Fixation (P-> A)

Complete articular

Schatzker type V Schatzker type VI

Operative tactic—complex tibial plateau fractures

• Require lateral and medial stabilization of fractures

• Stabilization:

– Double plating

– Locked plating

– External fixators

Construct 1: Double Plating4.5mm proximal tibial plate (lateral)5-hole 1/3 tubular plate (medial)

Construct 2: Locking Plating4.5mm tibial LCP

J Orthop Trauma. 2007

Result • Subsidence

– Lateral side: Double plate = One lateral locking

– Medial side: Double plate < one lateral locking • (p = 0.045)

Dual-plate fixation allows less subsidence when compared to isolated locked lateral plates.

Fixation of complete articular fractures

• Fragmented lateral plateau

• Simple medial plateau

• Reduce joint

• Stabilize both sides

• Medial first to give landmark for lateral reduction

Traction (ligamentotaxis) +Stabilization of medial fragment

Intraoperative

Double plating complete articular fractures

• Two incisions:

– Anterolateral and posteromedial

• Wound complications: May increase

• Indications:1.Displaced posteromedial fragment needs to

be buttressed with posterior plate

2.Medial articular involvement

3.Displacement of medial column

Displaced posteromedial fractures

Medial Articular and Metaphyseal Comminution

Medial Articular and Metaphyseal Comminution

Lateral Locked Implants for Medial Articular Fractures?

Incidence and Morphology of the Posteromedial Fragment in Bicondylar Tibial Plateau Fractures

Author Higgins TF et al. Barei DP et al.

JournalJ Orthop Trauma. 2009

J Orthop Trauma. 2008

Incidence59% (65/111 patients)

28.8% (42/146 patients)

total articular surface

25% 23%

sagittal fracture angle

73 degree 81 degree

posteromedial fragment height

42mm

5 mm of articular displacement

55%

Vertical Shearing PatternSaggital angle average 73 0

Displacement >5mm25% joint surface

Saggital fragment angle 81 0

Post coronal height 42mm

23% joint surface

Case

The rationale to use unilateral locking plate

1. Prevent second incision wound and reduce stripping medial periosteum

2. Provide enough stability for some fracture patterns

3. Save time

The Biomechanical study

Clin Orthop Relat Res. 2003

Conclusion:Double Plating (non-locked) = Lateral Locking Plate

No significanct difference of complications

Op time increased

Lateral Locking Plates: Pro

Can decrease the need for a secondary incision in certain fracture patterns

Can maintain the reduction of large and minimal displaced medial plateau separations

Can span medial comminution

Can’t decrease condylar wideningCan’t reduce fractures with medial plateau

separationCan’t reduce medial articular fracturesCan’t stabilize displaced posteromedial

fragments

Lateral Locking Plates: Con

Bone Grafting

• Cancellous bone graft

• Tricortical bone graft

• Bone substitue• Ballon tibioplasty

Metaphyseal defectbone graft or biologic

• A recent prospective, randomized, multicenter trial: compared the use of calcium phosphate cement with autologous cancellous bone graft for subarticular defects– A significantly higher rate of articular fragment subsidence occurred in the bone graft group• A meta-analysis of various fractures (including tibial plateau fractures):– Calcium phosphate cement to fill a defect leads to less fracture site pain compared with results in patients managed without defect grafting– results in improved articular support compared with cancellous•bone graftBone substitute is better than Bone

graft in pain and subsidendce

Not All Bicondylars Are Created Equal!

Simple Articular Complex Lateral Complex Both

Meta-Diaphyseal Dissociation

Outcomes

• Gaston et al, JBJS 87B(9) 2005

– 21% residual flexion contracture at 1 yr– 14% with NL Quadriceps Strength at 1 yr– 30% with NL Hamstring strength at 1 yr

• Barei et al, JBJS 88A(8) 2006

– Bicondylar with Dual Incisions– Satisfactory articular reduction associated with

better MFA– Significant Residual Dysfunction

Poor Results - Conclusions

• Osteoporosis• Infection• Increased Age• Varus Tilt• Menisectomy• Valgus Instability > 10˚

Post – Operative Care

• Active Suction Drainage • IV antibiotics x 48 hours • Hinged knee brace PRN

– ROM depends on intraop

• Early passive motion (CPM) to 45˚ - 60˚• Toe Touch WB x 8 - 12 weeks • Active Strengthening of Quadriceps• Flexion to 90˚ ASAP

Complications

• Loss of fixation– Osteoporosis– Diabetics

• Depression of articular surface• Non-union• Malunion• Post-traumatic OA• Infection

– Ill-timed Surgery– Soft Tissues– Incisions

Take Home Messages

• Analysis of soft tissue damage- Skin, ligaments, menisci

• Analysis of fracture pattern- Displacement, comminution- Joint subluxation or luxation

• Analysis of mechanical needs- Plate position and function

• Analysis of adequate stability after internal fixation

• - Bone and ligament

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