Proximal Tibial Fractures

1. 台灣骨科創傷醫學會103年度住院醫師研習課程 Proximal Tibial Fractures Kai-Cheng Lin 高雄榮總骨科部 林楷城 103/08/16 台中榮總

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

3. 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

4. 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

5. 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 bone Lateral meniscuc is vulnerable to injury after trauma

6. Mechanisms of Injury • The 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

7. 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

8. 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

9. Soft-tissue status • significant and clinically, relevant information -- fracture blisters -- non-wrinkling skin -- openlacerations -- tense compartments -- ecchymosis is present Bony injury is static and the soft-tissue injury is dynamic and can evolve

10. 水泡 Vs 血泡

11. Compartment syndrome -> fasciotomy Clinical Diagnosis No Hesitate if Doubt

12. 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

13. 小心

14. Tibial segmental fracture要注意上下關節

15. Traction view

16. Soft Tissue Injury on MRI 103 acute TPFs 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

17. The lateral collateral ligament (fibular collateral ligament)

18. 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 implants • Joint over-distraction may be detrimental to neurovascular structures

19. Temporary External Fixation Femur Anterior or Antero-Lateral Tibia Medial or Antero-Medial Draw Operative Incisions Place Outside Area of Injury

20. 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

22. Fracture classification OTA Type A Extraarticular Type B Partial articular Type C Complete articular 41-A1 41-A2 41-A3 (Schatzker I−IV) x 41-B1 41-B2 41-B3 (Schatzker V−VI) 41-C1 41-C2 41-C3

23. Fracture classification—Schatzker Low energy trauma High energy trauma Type I Type II Type III Type IV Type V Type VI partial articular fractures complete articular fractures

24. 3-Column concept

25. 3D CT

26. 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”

27. Indications of Non Op • Stable to varus and valgus stress • Not affect the coronal plane limb alignment • Minimal articular displacement • Nonambulatory 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

29. Key points of TPFs • Meniscal preservation is critical for long-term joint maintenance • A recent large series of bicondylartibial 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

30. Surgical Goals of TPF Obtain/Secure Articular Reduction Reduce Condylar Width Restore Axial Alignment Neutralize Meta-Diaphysis Early ROM Appropriate Soft Tissue Handling Direct Visualization Arthroscopic aid Reduce Joint Depression Reserve Meniscus Restore Alignment Repair Ligamentous Stability Radiographically Medial/Lateral Plates Lateral Plate/Medial ExFix Lateral Fixed-Angle Plate External Fixation Hybrid

31. A new way of thinkingMorphology+injury mechanism Varus + extension Valgus + extension Flexion

32. Principles for approach selection • Biomechanical fixation • Touch of depressed articular fragment • Soft tissue tolerance

33. 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

34. 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

35. Approaches Anterolateral Posteromedial

36. Anterolateral approach Check Meniscus

37. Partial articular fractures Schatzker type I Schatzker type II Schatzker type III Schatzker type IV

38. Schatzker type I • Split fracture • Open vs percutaneous treatment • Lag screws+/- buttress plate

39. Schatzker type II • Split depression fracture • Submeniscal arthrotomy • Elevation/bone graft • Lag screws/buttress plate

40. Schatzker III • Pure depression fracture • Amenable to percutaneous techniques with fluoroscopy +/- arthroscopy • Metaphyseal window for elevation and grafting • Screws beneath subchondral bone

41. Schatzker III Elevate the depressed central fragment from below

42. Type III Depression—preoperative 31-year-old

43. CT—articular depression

45. Arthroscopic Reduction IF medial depression fragment elevation

46. 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”

47. Raft Screws

48. 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

49. Schatzker type IV • Medial tibial plateau fracture • Frequently realigned knee dislocations • Associated with: -Peroneal nerve injury 5 − 50% -Popliteal artery injury 13 − 50%

50. Reduction