Osteotomies for Cartilage Protections. Jeffrey Halbrecht,, MD San Francisco, Ca

Transcription

1 Osteotomies for Cartilage Protections Jeffrey Halbrecht,, MD San Francisco, Ca

2 ACI/Osteotomy Osteotomy: Optimal Patient Selection Mechanical axis falls within involved compartment Mild joint space narrowing Or physiologic varus Opposite compartment intact Response to unloading trials Bracing, lateral heel wedges Not obese Compliance Nicotine use

3 Types of Osteotomies Unload femoral-tibial joint Varus HTO Opening wedge Closing wedge Valgus Distal femoral osteotomy Opening wedge Closing wedge Varus HTO Unload Patello-femoral femoral joint Anteriorization Medialization Antero-medialization

4 VARUS KNEE Why Osteotomy for Chondral Protection? Medial Joint Loading: A Quick Biomechanical Review Normal wb loads Normal joint mechanics: external varus moment throughout stance phase of gait This results in normal increase med comp loads Medial 60 %, lat 40% ( Kettelkamp 1976) OA situation: Increased varus moment due to narrowing of joint space as mech allignment shifts towards varus Harrington IJ: 1983 Also, altered gait causes increased adductor moment, increased knee loading rate, and shift in load bearing contact location to less tolerant (thick) cartilage ( Andriacchi 2005, 2006)

5 Benefit of HTO on artic ctlg Decrease med comp loads results in med. loads of 50% or less (Kettelkamp Best results >5 deg anat valgus --- Allows regeneration of cartilage Kettelkamp 76) Fibrocartilage cover best with valgus > 5 (Koshino Knee 2003) Improves results of microfx Clinical scores (Steadman AJSM 2004)

6 HTO: Biomechanical Goals Goal for chondral protection different than with OA! OA: Coventry: anatomic valgus 10 deg Mechanical valgus 3-55 deg Noyes: 62% tibial width ( 3.5 deg valgus mech axis) Chondral Protection: Restore mech axis 0-22 degrees valgus mech. Axis 50-55% 55% tibial width OA Ctlg protection

7 Indications: When to add an HTO My indications Varus allignment > 5 always 3-55 sometimes Very large lesions 0-22 usually not Compare to other side! Less aggressive with bilateral tibia vara to your ACI

8 Pre op planning: All patients! Long leg bilateral WB x-rayx ray Measure mechanical axis 45 degree flexion WB x-rayx ray

9 Opening vs Closing Wedge Clinical results = but closing wedge slightly more accurate (Brouwer JBJS (B) 2006) Clinical results = (Hoell Arch Ortho Tr Surg 2005) BUT..

10 Opening Wedge Osteotomy Advantages no fib osteotomy no deformity prox tib Easier conv to TKR No added lateral laxity Same side incision Disadvantages Longer time to heal Prolonged non WB Need graft Risk non union Patella baja Change tib slope

11 Closing Wedge Osteotomy Advantages No bone graft Earlier WB Rare non union Disadvantages Fibular osteotomy Deformity prox tib More difficult conv to TKR Add l Lateral incision Added lat. laxity

12 Opening Wedge: Ex Fix Ex Fix Advantages Obtain exact correction every time Minimal incision Early WB (2-4 4 wks) No residual hardware Disadvantage Pin care Medial frame against opp leg Unsightly 2 nd procedure ROH Frame on wks

13 Opening Wedge: Ex Fix Initial compression Begin distraction 1 week 1mm /day Remove weeks

14 Dome Osteotomy Technically demanding Biplanar correction No bone graft No effect on tibial slope No patella baja

15 HTO : Avoiding Complications

16 Closing Wedge Use rigid fixation Intermedics-Sulzer Sulzer- Centerpulse-Zimmer Compression Avoid violation medial cortex Early wb No immobilization

17 Osteotomies: : Avoiding NV Injury Closing wedge: Peroneal nerve Assoc. proximal fib osteotomy Tight post op bandage Bleeding Use post retractor Prox tib fib joint disruption vs osteotomy Hemostasis No tight bandages No tourniquet ( my preference) Ant tib artery Stay sub periosteal Opening wedge no reports of per nerve injury Protect post tib artery with retractors!

18 Parameter Total Complications Patients HTO Complications Medial Opening Wedge Miller et al 17 (35.4%) Gillogly 16 (30.2) 48 (ave. age 38 yrs) 34 males, 14 females Hardware Failure 2: 4.2% 3: 5.6% 53 (ave. age 38.1 yrs) 31 males, 22 females Lateral Cortex Disruption 2: 4.2% 2: 3.7% Delayed Union 2: 4.2% 4: 7.4% DVT Wound Infection Loss of Correction/ Revision 2: 4.2% 0 0 1: 1.8% 7: 14.2% 6: 11.3% (5/6 had allograft or bone substitute)

19 Medial Opening HTO Incisions: Surgical Technique Separate incision 5-77 cm posterior to any anterior incision Exposure: Protection of neurovascular structures, Patellar tendon Courtesy of Scott Gillogly MD

20 Medial Opening HTO Osteotomy Cut Positioning Surgical Technique Coronal: aim at level of fibular head Sagittal: : parallel to tibial slope 2cm below joint 1 cm from Lat cortex 2 CM 1CM Courtesy of Scott Gillogly MD

21 Osteotomy Distraction Medial Opening Wedge Technique Cont. Courtesy of Scott Gillogly MD

22 Medial Opening HTO Sagittal Plane: Tibial Slope Important to maintain normal slope As posterior slope increases, lose extention! Increasing post. slope promotes anterior translation (worsens ACL deficiency, diminishes PCL deficiency) Courtesy of Scott Gillogly MD

23 Medial Opening HTO Plate Placement and Fixation Place fixation at or posterior to mid-line of tibia on lateral view Fixation: 1 st generation: Puddu Plate 2 nd generation: Locking Puddu 3 rd generation: Reinforced plates, stronger screws (EBI) (Synthes( Synthes) Courtesy of Scott Gillogly MD

24 Medial Opening HTO Bone Grafting: Allograft Surgical Technique >7.5 mm of opening Wedges, tricortical IC cancellous chips, Bone Paste, BMP Autograft Use for higher risk pts (smokers, obese) Iliac Crest Local Source: Distal Femur or Tibia? Courtesy of Scott Gillogly MD

25 OW HTO: Avoiding Complications Lateral cortical fx: Leave 10mm bone A/P drill hole? ( Kessler CORR 2002 CW med cortex) Intra-articular articular fx 2 cm below joint line Slow distraction Increased post slope Sagital cut parallel to post slope Angled wedge plate Plate midline or post! Post gap 2x ant (Noyes) Non union Stronger plate / screws for corections > 10mm ( EBI) Bi/tri cortical graft.autograft?

26 OW HTO: Dealing with Intraoperative Complications Lateral cortical fx Staple Intra-articular articular fx Stable non dislplaced- leave alone Unstable /displaced: perc cannulated screw Allignment: check with flouro/ / leg loaded Slope: check pop ROM! Check flouro Change plate position more post. if necessary 68 68% reduction in torsional stiffness Miller AJSM 2005

27 Medial Opening HTO Summary Careful Patient Selection: Cautious of BMI > 40, Smokers, Noncompliant Sound Surgical technique: Always protect neurovascular structures, gradual opening wedge If Lateral Cortex disrupted, fix it with Staple Use stronger 2 nd or 3rd generation fixation methods Protected weight bearing 8-12 weeks Reduce pitfalls and complications

28 Valgus Knee: Lateral Compartment Defect: Correct alignment to neutral! < 10 degrees Prox tibia varus osteotomy Closing wedge Opening wedge >10 degrees Distal femoral osteotomy Lateral opening wedge ( < 15 degree?) Medial closing wedge Lateral opening wedge osteotomy (Marti JBJS 2001)

29 THANK YOU

30 Case Study N.L. 45 yo male Injury during martial arts MFC defect 4.0 CM x 2.5 CM 5 5,, 255 lbs Hx PMM 30% G-2 2 Tibia

31 N.L. Non WB X-RAYX

32 N.L. Long Leg WB X-RayX Ray

33 N.L. MRI

34 N.L. Lateral Compartment

35 Our Plan ACI HTO opening wedge