The document discusses meniscus transplants, including: 1) Meniscus transplantation can help reduce pain and improve function by restoring a biomechanically favorable environment in the knee. 2) A long-term study of 119 meniscus transplant cases found a 79% success rate, with the main factors affecting survival being increased age and number of previous surgeries. 3) Case studies demonstrate that meniscus transplantation, combined with cartilage repair procedures, can provide long-term benefits for patients with meniscus injuries and cartilage damage.

1. Meniscus Transplants Kevin R. Stone, MD Ann W. Walgenbach, RNNP Wendy S. Adelson, MS Jonathan R. Pelsis, MHS 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. Meniscus 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)

8. 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

9. 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.

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

11. Meniscus Transplantation 225 performed since 1997 Clinical Exam + Patient Reported Subjective Outcome (1, 2, 3, 5, 7, 10, 15+ yrs) IKDC WOMAC TEGNER

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

13. 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

14. 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?”

15. 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.

16. 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 of Study

17. 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)

18. 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

19. 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.

20. 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

21. 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%

22. 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.

23. 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

24. 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.

25. 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

26. Medial v. Lateral Transplants 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

27. Malalignment Severity of Mal-Alignment (p = 0.535) Severe Malalignment (>7º) (N = 10) Moderate Malalignment (5 – 7º) (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

28. 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

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

30. Patient Example: BK Lateral Meniscus Transplantation

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

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

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

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

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

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

37. 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

38. JA: Preoperative X-ray Lateral AP

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

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

41. JA Operative Images A B C Absent Meniscus Lateral Meniscus Transplant Transplant Placement

42. JA: 5 Months Post-Op Full Range of Motion with smooth articulation

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

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

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

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

47. 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)

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

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

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

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

52. GC: 3yr Postoperative X-ray AP Long-leg

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

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

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

56. 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

57. DB: Right Knee 10 Yr PostOp MRI

58. DB: 10 Yr Post Op XRAY

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

60. 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

61. RT: Pre-Operative MRI

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

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

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

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

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

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

68. 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 Improvements are maintained over the course of follow-up (2 – 12 yrs).