THE KNEE SOCIETY VIRTUAL FELLOWSHIP

Transcription

1 THE KNEE SOCIETY VIRTUAL FELLOWSHIP CHAPTER IX PARTIAL KNEE: MEDIAL, LATERAL AND PFR Revision of Failed Unicompartmental to Total Knee Arthroplasty Presented by: Keith R. Berend, MD COPYRIGHT 2016 THE KNEE SOCIETY

2 WHY DO MEDIAL UKA FAIL TODAY? Systematic Review: 37 cohort studies 2 registry-based studies 3967 failures: 388 time dependent 1305 implant design failures Aseptic loosening: 36% Disease progression: 20% van der List et al., J Arth 2016

3 MODES OF FAILURE IN EARLY, MIDTERM AND LATE Time UKA to Revision Early, <5 yrs Midterm, 5-10 yrs Late, <10 yrs P-value Number of UKA failures Aseptic loosening 25% 29% 29% Progression of OA 20% 38% 40% <0.001 Pain 8% 0% 5% Instability 3% 0% 0% Infection 7% 0% 5% Polyethylene wear 1% 6% 10% Bearing dislocation 17% 8% 2% Malalignment 1% 1% 0% Fracture 4% 0% 0% Tibial subsidence 7% 10% 5% Other* 7% 8% 5% *Other causes include implant failure, patella problems, arthrofibrosis, stiffness, other and unknown causes van der List et al., J Arth 2016

4 MODES OF FAILURE IN FIXED- AND MOBILE-BEARING Time UKA to Revision Fixed Bearing Mobile Bearing P-value Number of UKA failures Aseptic loosening 28% 35% Progression of OA 36% 24% <0.001 Pain 2% 14% <0.001 Instability 12% 1% <0.001 Infection 2% 6% Polyethylene wear 12% 0% <0.001 Bearing dislocation 0% 11% <0.001 Malalignment 0% 0% Fracture 0% 4% <0.001 Tibial subsidence 4% 1% Other* 5% 4% *Other causes include implant failure, patella problems, arthrofibrosis, stiffness, other and unknown causes van der List et al., J Arth 2016

5 Main Reason for Revision JIS 2016: REVISION OF FAILED PKA - ETIOLOGY , 174 patients, 180 knees Frequency Arthritic progression 31 (17%) Arthrofibrosis 2 (1%) Aseptic loosening 81 (45%) Bearing dislocation 4 (2%) Impingement 1 (1%) Excessive anterior slope 2 (1%) Infection 5 (3%) Instability 11 (6%) Malalignment 1 (1%) Medial tibial overload 7 (4%) Polyethylene wear 7 (4%) Recurrent effusions 3 (2%) Severe metallosis with catastrophic damage 1 (1%) Tibial collapse 24 (13%) 2nd Reason for Revision Frequency Arthritic progression 18 (10%) Aseptic loosening 4 (2%) Hypersensitivity to metal 1 (1%) Impingement 4 (2%) Instability 2 (1%) Malalignment 3 (2%) Medial tibial overload 3 (2%) Patellar clunk 1 (1%) Polyethylene wear 4 (2%) Tibial collapse 1 (1%)

6 ROLE OF PREOPERATIVE PATIENT CHARACTERISTICS ON OUTCOMES OF UKA: META-ANALYSIS 31 cohort studies 6 registries reported outcomes Inferior functional outcomes: Females Increased revision: Females Younger No inferior outcomes or increased revision: Obesity Preoperative patellofemoral OA ACL deficiency van der List et al., J Arth 2016

7 PREDICTORS OF SUBJECTIVE OUTCOME AFTER MEDIAL UKA 104 consecutive medial UKA 2.3 year follow-up WOMAC Results No influence BMI Gender Preoperative radiographic severity of the various knee compartments WOMAC Results Greater Age <65 years Postoperative alignment of 1-4º Zuiderbaan et al., J Arth 2016

8 REVISION OF UKA FOR UNEXPLAINED PAIN YIELDS INFERIOR RESULTS COMPARED TO REVISION FOR A DEFINED CAUSE 30 revision UKA to TKA 15 unexplained pain (UP) 15 defined cause (DC) OKS: UP: 19 to 25 DC: 23 to 38 VAS for Pain: UP: 7.7 to 5.4 DC: 7.4 to 1.4 Kerens et al., Bone & Joint J 2013

9 DIFFERENTIAL DIAGNOSIS OF PAINFUL UKA Extra-articular Peri-articular Intra-articular

10 EXTRA-ARTICULAR Hip disease Lumbar spine disease Vascular compromise / claudication Complex regional pain syndrome

11 PERI-ARTICULAR Extensor mechanism compromise Pes bursitis Biceps tendinitis Popliteal tendon impingement (lateral UKA) Periprosthetic fracture Traumatic fracture Tibial fracture through pin site Tibial stress fracture

12 INTRA-ARTICULAR Infection Aseptic loosening Disease progression Instability Polyethylene wear Bearing dislocation Malalignment Component overhang Osteolysis Implant failure Arthrofibrosis Loose cement Tibial subsidence Pain

13 DIAGNOSTIC STEPS History Pain description Psychological Clinical Radiographs Infiltration Aspiration Imaging Non-operative treatment Surgical treatment Laboratory

14 HISTORY Postoperative course Wound status Antibiotic treatment Previous treatment Pertinent radiographs, labs, documents

15 PAIN DESCRIPTION Rest / night pain Ascending / descending stairs Starting / loading pain Lateral pain

16 PSYCHOLOGICAL Depression Anxiety Psychological and psychopharmacological therapy

17 CLINICAL Gait Skin Circulation ROM Muscular atrophy Stability Mediolateral (ML) Anteroposterior (AP) Hip range of motion

18 LABORATORY TESTS WBC ESR CRP

19 ASPIRATION Leukocyte and polymorphonuclear cell counts Cultures Alpha defensin

20 RADIOGRAPHS AP PA flexed Lateral Merchant Alignment Flexion/extension lateral radiographs Fluoro-controlled Stress radiographs

21 INFILTRATION Intra-articular Extra-articular

22 SPECIAL IMAGING Ultrasound Bone scan CT scan

23 NON-OPERATIVE TREATMENT Physical therapy ROM Strengthening E-stimulation Ultrasound / phonophoresis Bracing NSAIDs Topical anti-inflammatory creams

24 LOOSENING Diagnosis Pathologic radiolucency Component migration Pain Example - Listed for revision Tibia loose Typical physiologic radiolucency IPO X-ray Femoral loosening

25 FEMORAL LOOSENING Diagnostic aids Flexion/extension views Arthroscopy & probe

26 FEMORAL LOOSENING Cause Inaccurate cuts & cementing Prevention Surgical Technique Posterior Saw Cut Cementation Technique Treatment Revision to TKR

27 TIBIAL LOOSENING Pathological radiolucency Poorly defined, >2mm, progressive, no sclerotic margin Migration AND Screened Xrays Compare postop

28 TIBIAL LOOSENING Cause & Prevention Radiolucency! Impingement ACLD Cementing error TIBIA NOT FLUSH Tibia too narrow Treatment Revision to TKR

29 LATERAL PROGRESSION Prevention PROTECT MCL Avoid overstuffing Pre-existing lateral OA Assess with Stress X-ray Avoid central ulcer Inflammatory arthritis Treatment Revise to TKR

30 TIBIAL FRACTURE Cause Bone weakened perioperatively Presents Perioperative or early postoperative Prevention Light hammer AVOID DEEP SAW CUTS Preserve posterior cortex Vertical cut Preserve posterior cortex Postop View

31 TREATMENT MCL attached to fragment so bearing stable Intraoperative Screw or Buttress Plate Postoperative: United Not United Varus acceptable OK Brace, ORIF Varus not acceptable TKA ORIF

32 TIBIAL PLATEAU FRACTURE Pre-op IPO 4 Months 6 wk s/p

33 TIBIAL FRACTURE / COLLAPSE

34 MEDIAL TIBIAL PLATEAU FRACTURE 7 case reports/series (23 patients) Intraop-18 months postoperative Associated with tibial pins for instrumentation Various manufacturers Saenz et al., Knee 2010 Rudol et al., J Arth 2007 Pandit et al., Orthopedics 2007 Yang et al., J Arth 2003 Brumby et al., J Arth 2003 Sloper et al., Knee 2003 Berger et al., CORR 1999

35 Brumby et al., J Arth 2003 Yang et al., J Arth 2003 Pandit et al., Orthop 2007 Vince & Cyran, J Arth 2004

36 PREVENT TIBIAL PLATEAU FRACTURES IN UKA BY AVOIDING: Medial placement of tibial saw guide fixation holes Excessive bone resection Excessive posterior slope Deep vertical saw cut Medial placement of tibial component Excessive impaction force Inadequate preparation of fixation peg hole / keel slot

37 Early INFECTION Acute Open debridement Antibiotics Chronic Loss of lateral cartilage Radiolucencies Thick, without sclerosis 2 stage revision to TKR Late

38 2-STAGE SPACERS

39 DISLOCATION % a/w learning curve? Occurs non-weight bearing Can be missed Patient can walk Diagnosis: X-ray

40 CAUSE AND PREVENTION Distraction Incorrect balance Stretched ligament Damaged ligament Displacement IMPINGEMENT Bearing Rotation Accurate balance Don t overstuff Protect MCL Bone & Cement Feeler gauge has to touch the vertical wall

41 DISLOCATION - TREATMENT MUA occasionally successful Open Remove bearing (posterior!) Identify and rectify cause Impingement Rotation Rectify problem New Bearing-Anatomic Same or 1mm thicker Fixed Bearing

42 LIMITED MOTION Poor flexion Tends to improve (reassure) MUA if <90º at 6 weeks (<1%) Loss of extension Tends to improve (unlike TKR) Provided osteophytes removed - Halves during operation, thereafter continues to improve

43 JIS: OUTCOMES OF MEDIAL MOBILE-BEARING UKA AFTER MANIPULATION (MUA) FOR ARTHROFIBROSIS medial MB-UKA in 1431 patients 0.7% MUA-UKA (12 patients, 13 knees) 5767 primary TKA in 4381 patients 6.0% MUA-TKA (316 patients, 345 knees) Mean follow-up: 5.3 years MUA-UKA vs. NonMUA-UKA patients preoperative: MUA-UKA were younger (51 vs. 63, p<0.001) MUA-UKA had higher KSF (72 vs 57, p<0.001)

44 JIS: OUTCOMES OF MEDIAL MOBILE-BEARING UKA AFTER MANIPULATION (MUA) FOR ARTHROFIBROSIS Postop Measure MUA-UKA nonmua-uka MUA-TKA P 1v2 P 1v3 Number of knees ROM (º) ΔROM (º) KS Pain ΔKS Pain KS Clinical ΔKS Clinical KS Function ΔKS Function UCLA scale Revised 15% (2) 5% (87) 5% (16)

45 POLYETHYLENE WEAR

46 UNEXPLAINED PAIN Rare but important Anteromedial over proximal tibia Most common Other sites Lateral, Medial, Posterior Rarely anterior regardless of preoperative pain location Aleto et al., J Arth 2008 Small et al., J Arth 2011 Small et al., J Arth 2013

47 ANTEROMEDIAL PAIN Not uncommon during first year Usually settles spontaneously At 1-year: 2% Higher or lower in others Treat expectantly Therapy: ultrasound/phonoporesis Pes anserinus injection: 1cc depo/3cc lidocaine Aleto et al., J Arth 2008 Small et al., J Arth 2011 Small et al., J Arth 2013

48 ETIOLOGY OF PAIN Pre-op pain not medial OA Bone-on-Bone Partial thickness may be asymptomatic Cementing error Overhang ( 3mm) Neuroma Unexplained Overtight Bearing Aleto et al., J Arth 2008 Small et al., J Arth 2011 Small et al., J Arth 2013

49 JIS: RELATIVE RISK OF REVISION TO TKA AFTER ARTHROSCOPY OF PAINFUL MEDIAL UKA Indication for arthroscopy # (%) Revised # (%) Relative Risk 95% CI P value ACL tear 1 (2%) 0 (0%) to Arthrofibrosis 7 (12%) 2 (29%) to Lateral compartment degeneration 11 (19%) 6 (55%) to Loose cement fragment 25 (43%) 0 (0%) to Recurrent hemarthrosis 2 (3%) 1 (50%) to Synovitis 12 (21%) 3 (25%) to Total (21%)

50 RECOMMENDATIONS TO DECREASE REOPERATIONS Extend skin incision as required Precise cement technique Meticulous removal of all cement Consider modular metal-backed tibial component for ease of cement removal Hamilton et al., J Arth 2006

51 ETIOLOGY OF PAIN Most likely overload of anterior medial tibia Aleto et al., J Arth 2008 Small et al., J Arth 2011 Small et al., J Arth 2013

52 UNEXPLAINED PAIN Investigate (eg. hip or back) X-ray normal (ignore radiolucency) Recommend against bone scan Treat conservatively Pain settles, even after 1 or 2 years Consider rest, injection Bisphosphonates? (ibandronic acid, alendronic acid) Second opinion Trained and knowledgeable Aleto et al., J Arth 2008 Small et al., J Arth 2011 Small et al., J Arth 2013

53 COPYRIGHT 2016 THE KNEE SOCIETY

54 COPYRIGHT 2016 THE KNEE SOCIETY

55 PREVENTION OF UKA FAILURE: THE 3 P S Perfect patient selection Full Thickness Cartilage Loss Fully Correctible Precise surgical technique Proper implant selection

56 THE ARTHROPLASTY PATIENT OF 2016 HAS BEEN RAISED IN A WORLD OF: Increased opportunity for education Significant availability of information Enhanced mobility Direct to consumer marketing Increased physical activity Higher expectations on all levels Health care cost pressures Physician accountability

57 TAKE HOME MESSAGE Avoid the lure of revising a UKA because of its simplicity Critically evaluate all pertinent information to establish the etiology of the revision Revising for unexplained pain may not yield the results you and your patient are seeking There is no harm in a little shaking and baking