The document discusses biologic knee replacement techniques, including meniscus allograft transplantation and its implications for patients with knee injuries, particularly focusing on the aging population. It examines the effectiveness, surgical techniques, complications, and influence of factors such as age and previous surgeries on the success rates of these procedures. The findings derive from long-term studies emphasizing the importance of preserving knee biology to improve outcomes for patients with damaged articular cartilage and meniscus loss.

1. Biologic Knee Replacement Kevin R. Stone, MD Ann W. Walgenbach, RNNP Wendy S. Adelson, MS Jonathan R. Pelsis, MHS Meniskus – Ersatz: Collagen Meniskus & Allograft 15. Janur 2010 Stone Research Foundation San Francisco

2. The Aging Knee Pediatric Normal Adult OA Adult

3. The Knee Joint

4. Meniscus Key shock absorber in the knee Torn 1.5M times annually US Minimal healing No spontaneous regeneration template

5. Loss of meniscus cartilage leads to: Increased forces across the knee joint Increased risk of articular cartilage damage Pain and arthritis in many cases Painful arthritic joints: Rough surfaces Harsh, degradative environment The Problem

6. Reduce pain and improve function Preserve the biology of the knee Restore a biomechanically favorable environment Provide a buffer to prevent bone-on-bone contact and pain The Goal

7. The Alignment Controversy Is osteotomy a two plane crude correction of a multiplanar deformed geometry? Is osteotomy really a correction? Are the complications worth it? “ Bad biomechanics ruins good biology any day of the week…” … However, biology lasts decades even in mechanically disadvantaged knees.

8. A Solution ? Biologic Knee Replacement Smooth, repair, replace, or regenerate damaged articular cartilage Meniscus reconstruction Meniscus allograft transplantation Fibrous interpostional joint arthroplasty Reduce pain and improve function Increase success of cartilage grafts

9. Outerbridge Grading System For Cartilaginous Degeneration Outerbridge RE. The etiology of chondromalacia patellae. J Bone Joint Surg Br, 1961;43: 752-7. Grade I Soft discolored superficial fibrillation Grade II Fragmentation < 1.3 cm 2 Grade III Fragmentation > 1.3 cm 2 Grade IV Erosion to subchondral bone (eburnation)

10. Meniscus Allograft Transplantation: Indications? Traditional thought: Meniscus Transplantation does not work in arthritic knees ( Noyes & Barber-Westin 1995, Stollsteimer 2000, Rath 2001) Current thought: Meniscus Transplantation does work in arthritic knees if damaged articular cartilage is treated as well (van Arkel 2002, Noyes 2004, Verdonk 2005, Cole 2006, Stone 2006, Farr 2007, Rue 2008)

11. Sizing: Surgeon Concerns “It takes me 6 months to get a properly sized meniscus.” “My measurements do not match the bank’s measurements.” “Is there an easier, more accurate method for sizing?”

12. Meniscus Allograft: Sizing Success rate may be dependant on accurate sizing Image-based sizing measures bony landmarks and insertion points however: Contrast limitations Identification of soft versus mineralized tissue interface Magnification errors Schaffer B, Kennedy S, Flimkiewicz J, Yao L. Preoperative Sizing of the Meniscal Allografts in Meniscal transplantation. Am Journal of Sports Med. Vol. 28, No. 4, 2000.

13. Supporting Studies: Sizing 148 heights and weights compared to MRI meniscus size Pearson’s Correlations (r): Height vs Total Tibial Plateau (TTP) r = 0.7194 Weight vs TTP r = 0.5470 TTP vs Medial and Lateral Meniscal Width r = 0.7386, r = 0.7209 TTP vs Medial and Lateral Meniscal Length r = 0.7040, r = 0.7209 Stone KR, Freyer A, Turek T, Walgenbach AW, Wadhwa S, Crues J. Meniscal sizing based on gender, height, and weight. Arthroscopy 2007;23-5:503-8 Meniscal Sizing Based on Gender, Height, and Weight

14. The Three-Tunnel Technique Replacing the Meniscus Stone KR, Walgenbach AW. “Meniscal Allografting: the Three-Tunnel Technique.” Arthroscopy – The Journal of Arthroscopic and Related Surgery. 2003, 19(4):426-30.

15. The Three-Tunnel Technique Movie

16. Articular Cartilage Paste Graft Procedure Step 1 Step 5 Step 4 Step 3 Step 2

17. Meniscus Transplantation 173 patients since 1997 Clinical Exam + Patient Reported Subjective Outcome (1, 2, 3, 5, 7, 10, 15+ yrs) IKDC WOMAC TEGNER The Stone Clinic Experience

18. Current Study: Long-Term Survival of Concurrent Meniscus Allograft Transplantation and Articular Cartilage Repair: A Prospective 12-Year Follow-Up Evaluation Pre-Allograft Allograft in place Transplantation OB IV

19. Study Design Study Inclusion Irreparable injury of the meniscus Or Loss of the meniscus More than 50% OB III/IV ROM ≥ 90° Study Exclusion Rheumatoid Arthritis Tri-compartment arthritis Total loss of joint space Simultaneous med/lat meniscus allograft transplantation

20. Patient Selection Young patients with cartilage loss and pain Older patients with cartilage loss and focal pain who want to remain athletic and delay or avoid a knee arthroplasty. “Doc, isn’t there a shock absorber you can put in my knee?”

21. Surgical Technique Medial Meniscus Allograft Transplantation: Performed utilizing periosteum, but not bone blocks, at the meniscus horns. Lateral Meniscus Allograft Transplantation: Preformed by preserving the bony block between the horns and inserting it into a bone trough.

22. 119 Meniscus Allograft Transplant Cases Mean age = 46.9 years (14.1 – 73.2 yrs) Mean follow-up = 5.8 years (2.1 mo – 12.3 yrs) 118 patients ≥ 3 months from injury to time of surgery (Mean = 14.2 years) Patient Population

23. Patient Population (N = 119) Neutral / Varus / Valgus Moderate ( 5 – 7°) / Severe ( > 7°) Grade III / Grade IV Medial / Lateral Male / Female None / Mild–Moderate / Severe (Kellgren-Lawrence)

24. Review of Literature Mixed Patient Studies N = 119 N = 100 N = 29 N = 31 N = 44

25. Results Procedure failure: Removal of allograft without revision (N = 7) , or progression to knee arthroplasty [N = 18 (TKA or UNI)]. 94/119 allograft cases successful (79%) Of 25 failures, Mean time-to-failure: 4.65 ± 2.99 years Range: 2.1 months – 10.37 years Kaplan-Meier estimated mean survival time was 9.93 ± 0.40 years [95%CI: 9.14,10.72] 13 patients were lost to follow-up

26. Complications 4 Early Postoperative Infections 3 Deep (1 Staphphylococcus Aures, 2 negative serologies) 1 Superficial (Staphylococcus Epidemis) All cases were treated arthroscopically with irrigation and debridement and IV antibiotics. All cases resolved, but one deep infection case ultimately failed, with the allograft being removed 12.5 months later.

27. Subsequent Surgeries – 1 4 2 Meniscus Allograft Revision – 2 1 12 Meniscus Allograft Repair – 1 9 22 Meniscectomy 1 1 – 4 Microfracture / Articular Cartilage Paste Grafting 1 4 6 20 Chondroplasty / Debridement – 1 1 2 Other 4 th N = 2 3 rd N = 10 2 nd N = 21 1 st N = 62 Subsequent Surgeries Primary Procedure

28. Kaplan-Meier Survival Analysis In Patients OB III/IV Time-to-failure analysis with continuous enrollment over 12-yrs Takes into account remaining patients (still intact / lost to follow-up (N=13) ) Intact/Lost To Follow-Up 94% 92% 84% 79% 67%

29. Cox Proportional Hazards Model What is it? A Cox model provides an estimate of a variable’s effect on survival after adjustment for other explanatory variables. In addition, it allows us to estimate the hazard (or risk) of procedure failure, given their prognostic variables.

30. What factors affect survival? Cox Proportional Hazards Model was used to explore the relationship between procedure failure and several covariates. Age (p = 0.026) Number of Previous Surgeries (p = 0.006) Number of Additional Surgeries Osteotomy performed concomitantly Number of concomitant procedures Outerbridge Grade (III or IV) Medial v. Lateral Allograft Joint Space Narrowing Malalignment Severity Alignment Type Sex NOT RELATED RELATED

31. Cox Model - Related Hazards Independent of actual time-to-failure, increased number of previous surgeries (p = 0.026) and increased age at time of surgery (p = 0.006) increases the risk of meniscus allograft transplantation failure.

32. Effect of Age 53 patients over 50 (Mean = 56 yrs) KM mean survival = 8.84 years [95% CI: 7.51,10.17] 71.7% (38/53) Success Rate 1 allograft removed 2 mo. post-op 14 progressed to Joint Arthroplasty @ mean 5.1 years 66 patients under 50 (Mean = 39 yrs) KM mean survival = 10.67 years [95% CI: 9.76,11.58] 84.8% (56/66) Success Rate 6 allografts removed @ mean 4.0 years 4 Progressed to Joint Arthroplasty @ mean 5.2 years

33. Medial v. Lateral Allografts Non Significant Hazard (p = 0.848) Medial (N = 85) KM mean survival: 9.91 ± 0.46 years Lateral (N = 34) KM mean survival: 10.17 ± 0.78 years

34. Malalignment Severity of Mal-Alignment (p = 0.535) Severe Malalignment (>7 º) (N = 10) Moderate Malalignment (5 – 7 º) (N = 39) 7 Osteotomies – 71.4% Success Rate (5/7) – 2 UNI 3 NO Osteotomy – 66.7% Success Rate (2/3) – 1 UNI – 50% Success Rate (4/8) – 2 TKA, 1 UNI, 1 Removed 8 Osteotomies – 80.6% Success Rate (25/31) – 2 TKA, 2 UNI, 2 Removed 31 NO Osteotomy

35. Subjective Outcome Scores IKDC, WOMAC, and TEGNER questionnaire follow-up schedule was preoperatively and at 2, 3, 5, 7, 10, 15 year post-op. Tegner Index was used to normalize return to activity across a diverse population * * Rodkey et al. Comparison of the collagen meniscus implant with partial meniscectomy. A prospective randomized trial. J Bone Joint Surg Am 2008;90-7:1413-26. Current Tegner activity score Highest reported pre-injury score = Tegner Index Score

36. Subjective Outcome Scores 1.00 0.90 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 0.00 Mean Tegner Index Score

37. Patient Example: BK 27 year old male Torn lateral meniscus in high school wrestling 1996 Partial lateral meniscectomy 2/96, 8/04 Pre-Operative X-Rays

38. BK: Pre-Op MRI MRI documents degenerative changes to LTP and loss of lateral meniscus

39. Patient Example: BK Lateral Meniscus Allograft Transplantation

40. Patient Example: BK 8 months post Arthroscopy for suprapatellar pouch and anterolateral swelling Lateral meniscus allograft transplant had healed

41. BK MRI 4 Years Post Op Lateral meniscus allograft appears normal and well positioned Patient reports no pain - “It feels really good”

42. Patient Example: JL 35 Year Old Female Right Knee 1984 - Lateral Meniscectomy 1988 - Lateral release 2003 - Knee locked, total meniscectomy Valgus Alignment

43. Patient Example: JL OB III/IV far-posterior aspect LFC, Microfracture LFC

44. JL: 4 months Post-Op Flexion contracture, debridement, closed manipulation, notchplasty No evidence of meniscal impingement Healed, intact lateral meniscus

45. JL: 6 years Post-Op Lateral Meniscus repair, chondroplasty, debridement, notchplasty

46. Patient Example: JA 37 Year old female Meniscectomy at age 20 R-Lateral Meniscus missing OB III chondral defect Microfracture, Chondroplasty LFC Long-Leg AP

47. JA: Preoperative X-ray Lateral AP

48. JA: Preoperative MRI Lateral meniscus: Absent posterior horn Articular Cartilage: Chondral damage to LFC

49. JA Operative Images A B C Deficient Lateral Meniscus Chondral Lesion of LFC Microfracture of Lesion

50. JA Operative Images A B C Absent Meniscus Lateral Meniscus Allograft Allograft Placement

51. JA: 5 Months Post-Op Full ROM with smooth articulation

52. JA: 2Yr Postoperative X-ray PA Flexion AP

53. JA: 2yr Post-operative MRI Healed lateral meniscal allograft

54. JA: 5Yr Postoperative X-Ray PA Flexion AP

55. JA: 5Yr Postoperative MRI Virtually unchanged meniscal allograft

56. Patient Example: GC 7 o varus L-knee Medial joint space narrowing Active 53 y.o. male. Meniscectomy: 1986, 1996 Medial meniscus-allograft 3/99 Paste Graft MFC & MTP High medial tibial osteotomy (Bionx wedge and allograft bone)

57. GC: Preoperative Images Sagittal MRI Loss of cartilage MFC PA Flexion Medial joint space narrowing

58. GC: Operative Images A B Bipolar lesions Morselization of MFC & MTP Loss of medial meniscus

59. GC: Operative Images A B C Placement of medial meniscal allograft Impaction of paste graft Paste Grafted Lesion

60. GC: Postoperative X-Ray Long-leg AP

61. GC: 3Yr Postoperative X-ray AP Long-leg

62. GC: 3Yr Postoperative Images 3 Years post-op L-medial allograft, osteotomy, & paste graft

63. GC: Comparison of healing 3-Years post-op allograft and paste graft to MFC Operative 3 yrs Post-op 3 yrs Post-op

64. Patient Example: SC 39 y.o. male Injury: 1970s playing hockey Meniscectomy (1999) Pre-op: Varus Joint space narrowing Right Medial Meniscus Allograft (2000)

65. SC: Preoperative MRI Bucket-handle tear with bipolar cartilage lesions on MFC & MTP Coronal Sagittal

66. SC: Operative Images Right knee bucket-handle tear displaced into intercondylar notch A B

67. SC: Operative Images Eburnated bone MFC Eburnated bone MTP Microfracture MTP Microfracture MTP

68. SC: Placement of Allograft Right Knee Placement of Medial Meniscal Allograft

69. SC: Comparison of healing Return to full activity Intermittent catching and pain 17 Mo Post-op Pre-op Note improved joint space compared to pre-op

70. SC: 17 Mo Post Op MRI Coronal Sagittal

71. SC: 2nd Surgery Movie 17 mo. Post Paste graft MFC + Meniscus Allograft Initial Surgery 17 mo. Post-op Meniscectomy

72. SC: 5 yr Post Op Images AP Allograft present with maturing degenerative changes Coronal

73. Patient Example DB 47 YO Male Skier R Knee: Chronic Pain Moderate to Severe Bilateral Pain

74. DB: Right Knee Right Knee: 09/91: Medial Meniscectomy, Drilling MFC, Chondroplasty 12/97: (triple) Medial Meniscus Allograft, Osteotomy, Art Cart MFC, MFx LFC 05/98: Revision Osteotomy, Medial Meniscectomy, Debridement, MFx MTP 10/2000: Ilizarov, Meniscectomy, Chondroplasty Pre-Op XRAY

75. DB: Right Knee 10 Yr PostOp MRI

76. DB: 10 Yr Post Op XRAY

77. DB: 10 Yr PostOp 63 YO, Tegner = 6, Skis 30+ days/yr, Snow skis 50+ days/yr.

78. 47 YO Female Beach volleyball injury (11/03) Failed debridement (11/03) Clinical exam: Pain at rest = 8/10 Severe swelling Giving way Meniscus Allograft, ACL reconstruction, Chondroplasty (3/05) Patient Example: RT

79. RT: Pre-Operative MRI

80. Torn medial meniscus MFC chondral lesion LFC chondral lesion Torn ACL Patient Example: RT

81. Medial meniscus Allograft Allograft Insertion Allograft placement ACL BTB allograft Patient Example: RT

82. Intact meniscus allograft ACL hardware removal due to prominence of fixation screw RT: 3 Months Post

83. Excellent joint space, intact meniscus allograft and ACL, but right knee clicking and catching RT: 18 Months Post

84. Intact meniscus allograft and ACL with diffuse thinning of patellofemoral cartilage RT: 18 Months Post

85. Surgery for catching due to chondral flap at patellofemoral joint Intact meniscus allograft and ACL RT: 18 Months Post

86. Patient Example: RM 57 Male Long-leg MRI Injury: Football tackle 1978 Previous Meniscectomy: 1978, 1993 Moderate varus mal alignment ( ≤ 7°) MFC OCD lesion

87. RM: Operative Images Severe Articular Cartilage Damage

88. RM: Operative Images Allograft insertion Articular Cartilage Paste Grafting Repair

89. RM: Operative Images High tibial opening wedge osteotomy

90. RM: 3.5 Years Post-Allograft Movie Primary Surgery Second Look, 3.5 years later

91. RM: Histology

92. RM: 3.5 Years Post Operative Long-leg

93. RM: 5 Years Post Operative MRI Sagittal Coronal

94. RM: 6 Year Post Operative X-Ray Long-leg Lateral

95. Patient Example: HM 5-7 o varus L-knee 18 Yrs Post meniscectomy 2 Meniscectomies (‘86, ’96) Pain >1 year Varus deformity Medial joint space narrowing L-medial meniscus-allograft (3/1999) Paste graft MFC & MTP High medial tibial osteotomy (Bionx wedge and allograft bone) Chondroplasty LFC Partial lateral meniscectomy Notchplasty

96. HM 4 Yrs 9 Mo Post Paste Graft Debrided lesion Healed paste graft

97. HM 4 Yrs 9 Mo Post Paste Graft Biopsy Histology

98. Biologic Knee Replacement Revision Surgery

99. Patient Example: TA 48 y.o. world-class female marathoner 86 marathons, 12 Ironmans 3 Double Ironman Triathalons Neutral alignment / mild medial joint space narrowing Meniscectomy: 4/2001 and 1/2002 AP X-ray R Medial Meniscus Allograft + Microfracture (bipolar lesions)

100. TA: Preoperative MRI Tear at horn of medial meniscus Osteoarthritis: medial compartment Saggital Coronal

101. 4/22/02: Right medial meniscus rim before allograft TA: Operative Images

102. TA: Meniscus Allograft Placement Preparation of medial meniscal allograft Placement of medial meniscal allograft Relationship of lesion to meniscus A B Movie

103. TA: Injury C Injury: 2 Mo. Post-op Swam in pool for 2 hours Developed immediate swelling A Movie

104. TA: Revision C A Movie Revision: 8 Months Post-allograft

105. TA: Revision: Operative Images Insertion of Meniscus Allograft with Articular Cartilage Paste Grafting Joint Arthroplasty 3/2006 (38 Mo. Post Op) A B C D

106. Patient Example: RT 34 YO male Partial meniscectomy for torn lateral meniscus (9/91), debridement 2006 Lateral joint line pain Severe pain and swelling with activities Positive Apley’s, McMurray’s, and hyperextension tests

107. RT: Pre-Op Imaging X-rays: Collapse of lateral joint space. Mild patellar spurring.

108. RT: Pre-Op MRI Loss of articular cartilage on posterior aspect of LFC Loss of posterior and central aspects of lateral meniscus PD SAG PD COR

109. RT: Surgery 11/2009 Lateral Meniscus Allograft transplantation Microfracture LFC and LTP (too far posterior for Articular Cartilage Paste Grafting) Removal of anvil osteophyte

110. RT: MRI 2 days Post Op Allograft intact without evidence of tear Anterior subluxation of the posterior aspect of the lateral meniscus with anterior displacement of the bone block (12 mm). FSE T2 SAG FSE PD SAG

111. RT: Revision Surgery Interval repositioning of the lateral meniscus 5 days post index procedure. Re-microfracture of distal femoral condyle to ensure good blood clot.

112. RT: MRI 1 Day Post Revision Repositioned Lateral Meniscus Allograft FSE T2 SAG FSE PD SAG

113. Conclusions Our research represents the largest and longest prospective study of meniscus replacement patients with severe chondral damage. Meniscus replacement can improve symptoms, even in severe OA . Meniscus replacement should not be limited to young patients without articular cartilage damage. Axial malalignment does not affect outcome.

114. Conclusions Height and weight can be used to size meniscal allograft tissue. Three-tunnel Technique is necessary to fix meniscus allograft to tibial plateau, not the surrounding tissue, to avoid meniscus subluxation

115. Conclusions Repair of severe articular cartilage damage combined with meniscus replacement provides significant improvements in activity, pain, and function. Improvements are maintained over the course of follow-up (2 – 12 yrs).

116. Conclusions The number of TKA surgeries is predicted to increase to 3.4 million by 2030 * , with increasing costs † . 18/119(15%) cases in our study progressed to knee arthroplasty 4.8 years after meniscus replacement (range: 1.3 – 10.4 yrs) . Average age at time of knee arthroplasty was 61 years (range: 52 – 72 yrs) . * Kurtz, AAOS Chicago, 2006 † Kurtz, JBJS, 2007

117. Conclusions Biologic joint reconstruction, rather than bionic (artificial) replacement, may be an appropriate first step for many people with knee joint arthritis.

118. Acknowledgements Thomas Turek Mark Coleman Abhi Freyer Ann Walgenbach Jonathan Pelsis Wendy Adelson Sharon Bobrow Meniscus Allograft Transplantation: 1997 – 2010 Articular Cartilage Paste Grafting: 1991 – 2010

119. 2009 Team 2005 Team