580 likes | 821 Views
Conservative Surgery for Knee Arthritis. Mark S. Sanders MD FACS Sanders Clinic for Orthopaedic Surgery and Sports Medicine Gainesville, Texas.
E N D
Conservative Surgery for Knee Arthritis Mark S. Sanders MD FACS Sanders Clinic for Orthopaedic Surgery and Sports Medicine Gainesville, Texas
We are indebted to Dr. Mark Coventry of the Mayo Clinic who first described osteotomy for degenerative arthritis. The original paper published in 1965 continues to be clinically relevant. Coventry, M. Osteotomy of the Upper Portion of the Tibia For Degenerative Arthritis of the knee: A PRELIMINARY REPORT. J. Bone and Joint Surgery 1965 47:984-990
Incidence of Total Knee Replacement • According to the NIH, approximately 300,000 TKR surgeries are performed in the United States per year. • This number is expected to increase several fold as the baby boomer generation ages.
Total Knee ReplacementWhy not just do it? • One of the most reliable operations in Orthopaedic Surgery • Reasonable expectation of survivorship to 25 years • But life expectancy continues to increase • Indications for TKA seem to include younger and younger people each year
The Knee SocietyAmerican Academy of Orthopaedic Surgeons • TKA patients must avoid: • High Impact Occupations and Sports • Farming, Ranching are high risk occupations • TKA patients may participate in: • Golf, Doubles Tennis, Croquet, Shuffleboard, downhill skiing on groomed runs
Is there something truly less “Invasive” out there? • In patients ≤ 60 yrs, alternatives to TKA deserve consideration • Osteotomy • Unicompartmental knee replacement • Arthroscopic Debridement?
Arthroscopic Debridement?IT JUST DOESN’T WORK • “In a controlled trial involving patients with osteoarthritis of the knee, the outcomes after arthroscopic lavage or arthroscopic débridement were no better than those after a placebo procedure”. • Moseley, RB et al., Arthroscopic Surgery for Osteoarthritis of the Knee?. NEJM 2002 359: 1169-1170
Unicompartmental Total Knee • Good pain relief in appropriate cases • Good survivorship • But it’s still a knee replacement • The same activity restrictions apply • Can not be successfully installed in the ACL deficient knee • Considered by many as the “First arthroplasty on a young person, and the first and last on an older person”.
Osteotomy: The Indications • Active lifestyle • ≤ 60 yrs • Single compartment disease • Opposite compartment intact or with minimal changes • Varus or valgus deformity • ≤ 10° loss of full extension • ≥ 90° flexion
Survivorship: End point considered at occurrence of TKA • 87% survivorship@5 yrs • 66% survivorship@10 yrs • Breakdown: • 51% survivorship@10 yrs in obese patients • 91% survivorship@10 yrs with normal BMI • 94% survivorship@10 yrs with maintenance of valgus correction • Coventry MB, Ilstrup DM, Wallrichs SL. Proximal tibial osteotomy: a critical long-term study of eighty-seven cases. J Bone Joint Surg [Am] 1993;75-A:196–201
Types of OsteotomyCoventry Closing Wedge 1960s http://www.eorthopod.com/images/ContentImages/knee/knee_tibial_osteotomy/knee_tibosteo_surgery01.jpg
Disadvantages of Closing Wedge Osteotomy • Removes bone from metaphysis • Requires fibular osteotomy • Peroneal neuropathy 15% • Lateral tibiofemoral instability 15% • Pathologic lowering of patella • Increases difficulty of later TKA
Opening Wedge Osteotomy1990s Noyes FR, Goebel SX, West J: Opening wedge tibial osteotomy: The 3-triangle method to correct axial alignment and tibial slope. Am J Sports Med 33:378-387, 2005.)
Advantages of Opening Wedge Osteotomy • Adds bone to tibial metaphysis • No lateral knee instability • Rare peroneal neuropathy • Later TKA no more difficult than usual
Disadvantages of Opening Wedge Osteotomy • Requires iliac bone graft • Pathologic lowering of patella • Poor fixation techniques required post op immobilization
The Biplanar Osteotomy • Staubli AE, De Simon C, Babst R, Lobenhoffer P. TomoFix: a new LCP-concept for open wedge osteotomy of the medial proximal tibia: early results in 92 cases. Injury 2003;34(Suppl 2):55-62. • Image Courtesy of Synthes
Advantagesof Biplanar Osteotomy • No need for iliac bone graft in nonsmokers • Stable fixation with locking TOMOFIX plate allows immediate ROM and partial weight bearing • Allows correction of 10 degrees of fixed flexion contracture • Anterior osteotomy can be made ascending or descending to prevent patella infera • Tibial slope can be adjusted to accommodate for cruciate ligament insufficiency
Biplanar osteotomy ascending anterior cut lowers patella height. Used for cases with patella alta or corrections of 10° and under Ascendinganterior cu t ascending anterior cut Slide courtesy of Synthes
Descending Anterior Osteotomy cut maintains preoperative patella height. Used for cases with patella infera or corrections of 10° and over to prevent patella infera Brinkman J-M, et al. Fixation stability of opening- versus closing-wedge high tibial osteotomy: A RANDOMISED CLINICAL TRIAL USING RADIOSTEREOMETRY J Bone Joint Surg Br, Nov 2009; 91-B: 1459 - 1465
Disadvantages of Biplanar Osteotomy HIGH RATE OF NONUNION IN SMOKERS
Presurgical Clinical Evaluation: The History • Joint line pain • Previous arthroscopic or open meniscectomy • Development of deformity • Lack of response to NSAIDS, acetaminophen, bracing, shoe modifications
Presurgical Clinical Evaluation:Physical Findings • JOINT LINE TENDERNESS • VARUS OR VALGUS DEFORMITY • ≤ 10 degrees fixed flexion • Further flexion ≥ 90 degrees • Normal examination of opposite compartment
Varus/Valgus • I used to mix these up all the time • Varus = Bowlegged • Valgus = Knock-kneed • Remember vaLgus • The L is for lateral • Some patients think the terms bowlegged or knock-kneed are offensive
Initial ImaginingRosenberg View Must be done weight bearing
Rosenberg View • Normal Medial Compartment joint space ≥ 4mms • Normal Lateral Compartment joint • Space ≥ 5mms Rosenberg, TD, et al. The Forty-Five-degree posteroanterior flexion weight-bearing radiograph of the knee. J Bone Joint Surg Am. 1988;70:1479-1483
Subsequent ImagingMRI • Normal opposite compartment • Bone marrow edema on ipsilateral side • Rule out unknown conditions
Orthoradiograms • Willy Sutton: “Where the money is” • One image includes hip through ankle • Calculation of angular deformity • Available at NTMC
Normal Orthoradiograms from Pailey Paley, D. (2003). Principles of Deformity Correction. Heidelberg, Germany: Springer-Verlag
THE DEFORMITY MUST BE LOCATED OSTEOTOMY MUST OCCUR THROUGH THE DEFORMED BONE OR AN OBLIQUE JOINT LINE WILL CAUSE FAILURESECONDARY TO SHEAR FORCES • Normal Proximal Tibia MPTA 85-90° • Normal Distal Femur mLDFA 85-90° • Joint line congruency angle ≤2°
2009 Gainesville, Texas 86° 82.9°
Correction of Deformity • Under correction leads to dissatisfaction and failure • Over correction leads to dissatisfaction • Correction of varus deformity to a mechanical axis of 183-185° of mechanical valgus leads to a survivorship of 94% at ten years • Valgus deformity should only be corrected to neutral or 180° Coventry MB, Ilstrup DM, Wallrichs SL. Proximal tibial osteotomy: a critical long-term study of eighty-seven cases. J Bone Joint Surg [Am] 1993;75-A:196–201
Correction for Varus Deformity DeLee and Drez's Orthopaedic Sports Medicine, 3rd ed. Redrawn from Dugdale TW, Noyes FR, Styer D: Pre-operative planning for high tibial osteotomy: Effect of lateral tibiofemoral separation and tibiofemoral length. Clin Orthop 271:105-121, 1991.)
2009, Gainesville, Texas 2009 Gainesville Texas
Surgical Preparation • Nasal MRSA screening • If positive treat with mupirocin and Hibiclens showers • Antibiotic prophylaxis with Vancomycin or Clindamycin • If MRSA negative prophylaxis with cephalexin
Anesthesia • Spinal anesthesia reduces the incidence of thromboembolic disease in total joint replacement. Hu, S., et al., Prevention of Venous Thromboembolic Disease After Total Hip and Knee Arthroplasty J. of Bone and Joint Surgery - British Volume. 2009 91-B, Issue 7, 935-942
Tourniquet • Abandoning the tourniquet reduces the incidence of thromboembolic disease and post tourniquet pain • EBL for tibial osteotomy typically is < 100 ccs. So what is the tourniquet for anyway?
Diagnostic/Surgical Arthroscopy • Confirms diagnosis on affected side • Confirms normalcy of opposite side • Significant abnormality of opposite side contraindicates osteotomy • Joint debridement can be performed although it may not really be necessary
Medial Compartment OA Findings in this case: Exposed tibia and femoral bone meniscectomy Psuedogout
Osteotomy Exposure • Midline or oblique medial incision • Extraperiosteal dissection • Inferior retraction of anserine tendons • Section of superficial MCL reduces contact forces on the medial side • Retractor placed posteriorly to protect neurovascular bundle
Biplanar Tibial Osteotomy • Oblique posterior 2/3rds of tibia at level of tibial tubercle from medial to lateral • Osteotomy is incomplete and retains intact lateral one centimeter of tibia • Osteotomy of anterior 1/3 of tibia including tibial tubericle is made either ascending or descending
Tibial Osteotomy • Spreader chisel is carefully inserted into posterior osteotomy and opened to appropriate degree of correction under fluoroscopic control with plastic deformation of the lateral cortex. • The anterior osteotomy slides maintaining bone to bone contact. • TOMOFIX plate is applied
Schematic of Biplanar Osteotomy Slide courtesy of Synthes
Computer Navigation • Is currently under study. Preliminary results indicate that accuracy of correction is improved by these methods • Current cost is in excess of $100,000 but improvements continue to occur in the system • Hard to know when to purchase • We probably will be using it within a couple of years Wang, G. et. al. A fluoroscopy-based surgical navigation system for high tibial osteotomy Source Technology and Health Care 2005 Volume 13 , Issue 6 Pages: 469 - 483
Post Op Management • immediate ROM exercises in the RR. • Cryotherapy is utilized • Thromboembolic Prophylaxis • Not Necessary: • CPM Machine • Parental analgesics • Oral analgesics stronger than Class Three • Femoral or epidural blocks • Discharge from hospital next morning
Thromboembolic Prophylaxis • Spinal anesthesia • Foot pumps • TED hose • Immediate ROM and ambulation with partial weight bearing by next morning • ASA for ordinary risk cases • Warfarin for high risk cases