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Fractures of the Tibial Plateau

Douglas R. Dirschl, MDThomas Ellis, MDBruce French, MD

Outline• Anatomy• Mechanism of Injury• Evaluation• Emergency Management• Surgical Indications• External Fixation• Internal Fixation• Outcomes

Osseous Anatomy• Proximal Tibia

– widens into lateral and medial tibial flares– flares lead to medial and lateral plateau (condyles)– intercondylar eminence – tibial tubercle (patellar tendon)– Gerdy’s tubercle (ITB)– proximal tib/fib joint

Osseous Anatomy

• Medial Plateau VS– larger– concave: frontback– sideside– lower than lateral side– slopes posteriorly 10°– cartilage 3mm– medial condyle stronger

bone– bears 75% of weight

• Lateral Plateau– smaller– convex: frontback– sideside– higher than medial– slopes posteriorly 7°– cartilage 4 mm– softer bone

Meniscus

• Fibrocartilage• 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 most of joint reactive force

Meniscus

• Medial meniscus– “C” shaped– intimately attached to MCL– bears equal joint reactive force as bone

Introduction/Mechanism of Injury

• Mean age in most series of tibial plateau fractures is about 55 years– Large percentage over age 60

• Elderly population is increasing in numbers– Fastest growing segment of US population

• Tibial plateau fractures comprise 8% of all fractures in the elderly population (Hohl)

Mechanism of Injury

• Mechanism of injury is fall from standing height in most patients– MVA is increasing as % of fractures– High energy fracture patterns increasing in this

age group!• Most common fracture pattern is split-

depressed fracture of lateral tibial plateau (80% of fractures)

Demographics of Plateau Fractures

• 1% of all fractures• 8% of all fractures in the elderly• lateral plateau involved 55-70%• medial plateau involved 10-20%• both involved 10-30%

Mechanism • Mechanism of injury is important when

considering treatment options, timing and associated injuries

• remember… Force = Mass X Acceleration• even if the xrays are similar, these are

completely different injuries

Evaluation• Trauma Evaluation

– ABCs– Associated Injuries

• Evaluation of Limb– Gentle exam for knee stability– Observation of soft tissues– Neurovascular evaluation– Evaluate for compartmental syndrome

• Imaging Evaluation

Physical Exam• Soft Tissue Assessment

– Tscherne & Goetzen (closed injury)• grade 0: minimal soft tissue damage/ indirect force• grade 1: superficial abrasion/contusion via pressure from

within• grade 2: deep, contaminated abrasion with localized

skin/muscle contusion: impending comp. syn.• Grade 3: extensive skin contusion/crush: sobq avusion;

underlying muscle damage; decompensated cs– Gustilo and Anderson (open injury)

Physical Exam

• Neurologic exam– peroneal nerve!

• Vascular exam– popliteal artery and medial plateau injuries– beware the of the knee dislocation posing as a

fracture– beware of posteriorly displaced fracture fragments– ABI <0.9 urgent arterial study

Physical Exam

• Compartment syndrome• KNEE STABILITY

– varus/valgus in full extension– may require premedication

• aspiration of knee effusion/hematoma• replace with lidocaine+marcaine

Evaluation of Soft Tissues

• Proximal and distal tibia subcutaneous

• Soft tissue remains compromised for at least 7 days

• Early ORIF risks wound sloughexposed hardware

Evaluation• Plain radiographs

– AP, lateral, ? oblique of knee on 17-inch cassettes– AP and lateral of entire tibia– Traction radiographs

• Very helpful for complex fractures• Traction can be applied by temporary spanning ex-fix

– CT scan indications• Fractures for which you are considering nonsurgical

care• Complex fractures to assist in surgical planning• Always obtain CT after applying traction

AP and Lateral Radiographs

AP and Lateral Radiographs

AP and Lateral Radiographs

Pre-traction

Post-traction

Tomography

Computed Tomography• Indications

– Fracture in an active patient for which you are considering nonsurgical care

– Complex fracture– To aid surgical planning of approach,

technique, screw position, etc.• Indications for 3-D reconstructions

– Rare• Rapid prototyping?

Computed Tomography

Computed Tomography

Classification:Schatzker

I

II

III

Classification:Schatzker

IV

VVI

Classification:AO/OTA

Classification:AO/OTA

Classification:AO/OTA

Urgent Management• Rule out compartmental syndrome• Provide temporary external stabilization

– Relieves pain– Stabilizes bone and soft tissues

• Consider spanning external fixation if:– Complex fracture pattern– Large amount of shortening– Soft tissue conditions or other injuries make

immediate ORIF unsafe

Compartmental Syndrome

Spanning External Fixation

Spanning External Fixation

Surgical Indicatons

• Open Fracture – I&D, spanning ex-fix• Extensive soft tissue contusion – spanning ex-

fix• Closed fracture

– Varus/valgus instability of the knee– Varus or valgus tilt of the proximal tibia– Meniscal injury/previous mensicectomy– Articular displacement or gapping???

Should You Operate on These Fractures?

• “The objective of treatment of tibial plateau fractures is precise reconstruction of the articular surface and stable fragment fixation allowing early motion”

• Do outcomes data support these objectives?

Should You Operate on These Fractures?

• Tenet: patient outcome will vary directly with the accuracy of the articular reduction

• The literature seems to indicate that articular incongruity is tolerated fairly well and that other factors may be more important in determining outcome

Lucht et al (Acta Orthop Scand 1971; 42:366)

• 109 fractures treated op and non-op

• 3-10 mm articular depression– 78% acceptable functional result

• > 10 mm articular depression– 79% acceptable functional result

Ramussen (JBJS 1973; 55A:1331-1351)

• 183 patients followed for 7.3 years

• Functional outcome no different in 40 patients with > 5 mm articular depression than in those with < 5 mm

• No correlation between residual articular depression and arthrosis

Lansinger et al (JBJS 1986; 68A:13-19)

• 102 of Rasmussen’s 183 patients followed for 20 years

• No change in functional outcomes from the original study

7 yrs: 87% G or E 20 years: 90% G or E

• All 20 patients with 5-10 mm incongruity had excellent results (including 9 with instability of the knee)

Lansinger et al (JBJS 1986; 68A:13-19)

• All 5 patients with > 10 mm incongruity and stable knees had G or E result

• Poor outcome occur only with combination of:– Central depressed condylar fragment– > 10 mm articular incongruity– Mediolateral instability of the knee

Koval et al (J Orthop Traum 1994; 6:340-346)

• 18 patients followed 16 months

• Clinical results no different for patients with anatomic (< 2 mm) or nonanatomic (> 2 mm) reductions

• 5 nonanatomic reductions:• 2 excellent, 3 good results

Blokker et al (Clin Orthop 1984; 182:193-199)

• 60 patients followed for 39 months

• Adequacy of articular reduction strongly associated with outcome

• Satisfactory results:– Anatomic reduction 86%– 1-4 mm step-off 75%– > 5 mm step-off 0%

Blokker et al (Clin Orthop 1984; 182:193-199)

• To attain “satisfactory” rating• Satisfactory clinical result AND• Satisfactory radiographic result

– Criterion for satisfactory radiographic result was < 5 mm articular incongruity

• Patients with > 5 mm incongruity were assigned an unsatisfactory result, regardless of clinical outcome

Importance of Factors Other Than Articular Congruity on Outcome

• The literature clearly indicates that other factors are critically important to outcome:

– Angular malignment of the proximal tibia– Resection of the meniscus– Ligamentous instability

Angular Malalignment of the Proximal Tibia

• Rasmussen (Acta Orthop Scand 1972; 43:566-572)

– Incidence of arthrosis:• Valgus < 10o 14%• Valgus > 10o 79%

– Any amount of varus angulation was bad– Independent of articular congruity

Meniscectomy

• Jensen et al (JBJS 1990; 72B:49-52)

– Higher rate of arthrosis in patients who had undergone meniscectomy at surgery

• Honkonen (J Orthop Traum 1995; 4:273-277)

– 70% arthrosis in patients who had undergone meniscectomy

– results were independent of the amount of articular incongruity

Ligamentous Instability• Rasmussen (Acta Orthop Scand 1972; 43:566-572)

– 46% arthrosis in patients with mediolateral instability (17% incidence in all others)

• Lansinger (JBJS 1986; 68A:13-19)

– Mediolateral instability a necessary condition for a poor functional outcome

• Honkonen (J Orthop Traum 1995; 4:273-277)

– 69% arthrosis in patients with mediolateral instability > 10o

Surgical Indicatons

• Open Fracture – I&D, spanning ex-fix• Extensive soft tissue contusion – spanning ex-

fix• Closed fracture

– Varus/valgus instability of the knee– Varus or valgus tilt of the proximal tibia– Meniscal injury/previous mensicectomy– Articular displacement or gapping

90 yo Male Injured in MVA

Non-op

Care!

Surgical TreatmentDepressed Fractures (Schatzker 3)

Surgical TreatmentDepressed Fractures (Schatzker 3)

Surgical TreatmentDepressed Fractures (Schatzker 3)

Surgical TreatmentDepressed Fractures (Schatzker 3)

Surgical TreatmentDepressed Fractures (Schatzker 3)

Surgical TreatmentSplit Fractures (Schatzker 1)

Surgical TreatmentSplit Fractures (Schatzker 1)

Surgical TreatmentSplit Fractures (Schatzker 1)

Surgical TreatmentSplit Fractures (Schatzker 1)

Surgical TreatmentSplit Depression Fractures (Schatzker 2)

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

Biomechanics: Subchondral 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 signicantly enhance load tolerance depress articular surface Beris et al Bull Hosp Joint Dis 1996

Large or Small Fixation for the Lateral Plateau?

• No significant difference between fixation strengths small vs large frament (Hubbard et al. A J Ortho, 1999)

• Karunaker et al. J Ortho Trauma 2002– No significant difference in overall stiffness between: large

fragment; periarticular small fragment plate; 3.5 mm subchondral screws with separate 1/3 semitubular anti-glide plate

– local depression stiffness > with 3.5 mm vs 6.5 mm screws

Clinical Example

• 57 female• ped struck

Instability

• Arrows (leftright)– depressed joint– lateral wall– meniscus

• Elevation of joint• temporary fixation• bone graft defect

Fixation

Lateral Split Depression PlateauClustered K-wires

Surgical TreatmentMedial Fractures (Schatzker 4)

Operative ManagementHigh Energy Fractures

• Soft tissue envelop more of an issue• treatment aimed at minimizing iatrogenic,

surgically induced complications– limited ORIF with external fixation

• hybrid• monolateral half pin

– composite fixation– open reduction joint with perc. locked plate (LISS)– temporary knee spanning external fixation with delayed

double plating/ locked plate

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Hybrid Ex-Fix

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Hybrid Ex-Fix

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Hybrid Ex-Fix

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Hybrid Ex-Fix

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Hybrid Ex-Fix

Hybrid External FixationResults

• Duration external fixation 12-16 weeks• ROM: 100-120°• knee score average 80-90 on 100 point scale• complications

– nonunion 5%– angular malunion 10%– deep infection 5%– PIN TRACT INFECTION COMMON

Hybrid External FixationPin Tract Infections

• Generally respond to antibiotics + pin care• may result in septic joint (10%)• Ways to avoid septic joint:

– stable fracture reduction (impact metaphysis)– keep pins >15mm from joint– beware cavity communicating metaphysisjoint– gentle post op ROM to avoid pin irritation– aggressive investigation post op knee effusion– consider cross joint adjunct fixation

Temporary Knee Spanning External Fixation with delayed ORIF

• Acute: femur tibia external fixation– reduction via ligamentotaxis– pins in tibia at least 5cm from distal fracture line

• CT scan• ORIF when soft tissue recovers

– up to 3 weeks!!!– Double plating– unilateral locked plate

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Percutaneous Plating

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Percutaneous Plating

Posteromedial Approach

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Percutaneous Plating

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Locking Plates

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Locking Plates

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Locking Plates

Surgical TreatmentBicondylar Fractures (Schatzker 5 and 6)

Locking Plates

Locked Plate Pitfalls

Hole # 13 12 11 10

DistanceAnt. Nv bundleto drill sleeve(mm)

0 3 6 8

Distance supperoneal n. todrillsleeve(mm)

7 6 9 12

Locked Plate- Results

• 52 proximal tibia fractures• 31/52 bicondylar plateau• 18/52 open injuries• 1 nonunion• 4 malunion• average range of motion 2-116°• 2 infections (both grade 3B)

Stannard et al. OTA 2001

Locked Plate- Results

• 75 bicondylar plateau fractures• 16/75 open injuries• 6 delayed unions: 4/6 union with bone graft• 1 deep infection• 9 loss of fixation: 8/9 technique related• 78% good/excellent results (Rasmussen)

Gosling, Krettek et al. OTA, 2002

Can I Synthesize this Information into Clear Guidelines?

• Articular incongruity 5 mm or less• Stable knee in full extension• Normal varus/valgus alignment

• Non-operative Care!

90 yo male injured in MVA

Non-op

Care!

Can I Synthesize this Information into Clear Guidelines?

• Articular displacement > 5 mm AND• More than 10 degress varus/valgus

instability to exam in full extension

• Operative Care!

Can I Synthesize this Information into Clear Guidelines?

• Articular displacement > 5 mm AND• Knee stable to varus/valgus stress in full

extension

• Favor non-operative care

Can I Synthesize this Information into Clear Guidelines?

• Varus or valgus tilting of proximal tibia more than 5 degrees

• Operative Care!

Postoperative Management

• Immediate PROM/AROM of knee• Shower beginning 48 hours after surgery

– Ok to shower with ex-fix in place• Routine Pin site care (if ex-fix)• TDWB for 8-12 weeks• Sutures out in 2 weeks• Xrays in 4-6 weeks

Outcomes

• See slides 27-39 in this presentation• Outcome depends on:

– Varus valgus stability of the knee– Varus/valgus alignment of the proximal tibia– Presence of an intact meniscus– Articular congruity (to a lesser extent)

Treatment Goals• Focus on restoring stability and proximal tibial

alignment to the knee, rather than restoring anatomic alignment of the articular surface at all costs

• Use minimally invasive techniques, when possible

• Other techniques are preferable to hybrid ex-fix

• Move the knee early in all patients!

Thank You!

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