Biologic Knee Replacement

Kevin R. Stone, MDAnn W. Walgenbach, RNNP

Wendy S. Adelson, MSJonathan R. Pelsis, MHS

Meniskus – Ersatz:Collagen Meniskus & Allograft15. Janur 2010 Stone Research Foundation

San Francisco

The Aging Knee

Pediatric Normal Adult OA Adult

The Knee Joint

Meniscus

• Key shock absorber in the knee

• Torn 1.5M times annually US

• Minimal healing– No spontaneous

regeneration template

• 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

• 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

The Alignment Controversy

• Is osteotomy a two plane crude correctionof 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.

A Solution ?Biologic Knee Replacement

1. Smooth, repair, replace, or regenerate damaged articular cartilage

2. Meniscus reconstruction

3. Meniscus allograft transplantation

Fibrous interpostional joint arthroplasty

• Reduce pain and improve function

• Increase success of cartilage grafts

Outerbridge Grading System

For Cartilaginous Degeneration

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)

Outerbridge RE. The etiology of chondromalacia patellae. J Bone Joint Surg Br, 1961;43: 752-7.

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)

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?”

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.

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

The Three-Tunnel TechniqueReplacing 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.

The Three-Tunnel Technique

Movie

Articular Cartilage Paste Graft Procedure

Step 1

Step 5Step 4

Step 3Step 2

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

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 placeTransplantation

OB IV

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

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?”

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.

• 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

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)

Review of Literature

Mixed Patient Studies

N = 119

N = 100

N = 29

N = 31

N = 44

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

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.

Subsequent Surgeries

Primary Procedure

Subsequent Surgeries

1st

N = 62

2nd

N = 21

3rd

N = 10

4th

N = 2

Meniscus Allograft Revision 2 4 1 –Meniscus Allograft Repair 12 1 2 –Meniscectomy 22 9 1 –Microfracture /Articular Cartilage Paste Grafting 4 – 1 1

Chondroplasty / Debridement 20 6 4 1Other 2 1 1 –

Kaplan-Meier Survival AnalysisIn 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%

Cox Proportional Hazards ModelWhat 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.

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 RELATEDRELATED

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.

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 Rate1 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 Rate6 allografts removed @ mean 4.0 years

4 Progressed to Joint Arthroplasty @ mean 5.2 years

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

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

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

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 T

egner Index S

core

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

BK: Pre-Op MRI

• MRI documents degenerative changes to LTP and loss of lateral meniscus

Patient Example: BK

• Lateral Meniscus Allograft Transplantation

Patient Example: BK 8 months post

• Arthroscopy for suprapatellar pouch and anterolateral swelling

• Lateral meniscus allograft transplant had healed

BK MRI 4 Years Post Op

•Lateral meniscus allograft appears normal and well positioned

•Patient reports no pain - “It feels really good”

Patient Example: JL

• 35 Year Old Female

Right Knee • 1984 - Lateral

Meniscectomy• 1988 - Lateral release• 2003 - Knee locked, total

meniscectomy• Valgus Alignment

Patient Example: JL

OB III/IV far-posterior aspect LFC, Microfracture LFC

JL: 4 months Post-Op

• Flexion contracture, debridement, closed manipulation, notchplasty

• No evidence of meniscal impingement

• Healed, intact lateral meniscus

JL: 6 years Post-Op

• Lateral Meniscus repair, chondroplasty, debridement, notchplasty

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

JA: Preoperative X-ray

LateralAP

JA: Preoperative MRI

Lateral meniscus:• Absent posterior horn

Articular Cartilage:• Chondral damage

to LFC

JA Operative Images

A B CDeficient Lateral

MeniscusChondral Lesion of

LFCMicrofracture of

Lesion

JA Operative Images

A B CAbsent Meniscus Lateral Meniscus

AllograftAllograft

Placement

JA: 5 Months Post-Op

Full ROM with smooth articulation

JA: 2Yr Postoperative X-ray

PA Flexion AP

JA: 2yr Post-operative MRI

• Healed lateral meniscal allograft

JA: 5Yr Postoperative X-Ray

PA Flexion AP

JA: 5Yr Postoperative MRI

• Virtually unchanged meniscal allograft

Patient Example: GC

7o 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)

GC: Preoperative Images

Sagittal MRI

Loss of cartilage MFC

PA Flexion

Medial joint space narrowing

GC: Operative Images

A BBipolar lesions Morselization of MFC & MTP

Loss of medial meniscus

GC: Operative Images

A B CPlacement of medial

meniscal allograftImpaction ofpaste graft

Paste GraftedLesion

GC: Postoperative X-Ray

Long-leg AP

GC: 3Yr Postoperative X-ray

APLong-leg

GC: 3Yr Postoperative Images

3 Years post-op L-medial allograft, osteotomy, & paste graft

GC: Comparison of healing

3-Years post-op allograft and paste graft to MFC

Operative 3 yrs Post-op 3 yrs Post-op

Patient Example: SC

• 39 y.o. male• Injury: 1970s playing hockey

• Meniscectomy (1999)

• Pre-op: • Varus • Joint space narrowing

• Right Medial Meniscus Allograft (2000)

SC: Preoperative MRI

Bucket-handle tear with bipolar cartilage lesions on MFC & MTP

Coronal Sagittal

SC: Operative Images

Right knee bucket-handle tear displaced into intercondylar notchA B

Eburnated bone MFC Eburnated bone MTP

Microfracture MTP Microfracture MTP

SC: Operative Images

SC: Placement of Allograft

Right Knee Placement of Medial Meniscal Allograft

SC: Comparison of healing

Return to full activity

Intermittent catching and pain

17 Mo Post-opPre-op

Note improved joint space compared to pre-op

SC: 17 Mo Post Op MRI

Coronal Sagittal

SC: 2nd Surgery

Movie 17 mo. Post Paste graft MFC + Meniscus Allograft

Initial Surgery 17 mo. Post-opMeniscectomy

SC: 5 yr Post Op Images

AP

Allograft present with maturing degenerative changes

Coronal

Patient Example DB

• 47 YO Male Skier

• R Knee: Chronic Pain

• Moderate to Severe Bilateral Pain

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, ChondroplastyPre-Op XRAY

DB: Right Knee 10 Yr PostOp MRI

DB: 10 Yr Post Op XRAY

DB: 10 Yr PostOp

63 YO, Tegner = 6, Skis 30+ days/yr, Snow skis 50+ days/yr.

• 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

RT: Pre-Operative MRI

Torn medial meniscus

MFC chondral lesion

LFC chondral lesion Torn ACL

Patient Example: RT

Medial meniscus Allograft Allograft Insertion

Allograft placement ACL BTB allograft

Patient Example: RT

• Intact meniscus allograft• ACL hardware removal due to prominence of fixation screw

RT: 3 Months Post

Excellent joint space, intact meniscus allograft and ACL, but right knee clicking and catching

RT: 18 Months Post

Intact meniscus allograft and ACL with diffuse thinning of patellofemoral cartilage

RT: 18 Months Post

• Surgery for catching due to chondral flap at patellofemoral joint

• Intact meniscus allograft and ACL

RT: 18 Months Post

Patient Example: RM57 Male

Long-leg MRI

• Injury: Football tackle 1978 • Previous Meniscectomy: 1978, 1993• Moderate varus mal alignment (≤ 7°)• MFC OCD lesion

RM: Operative Images

Severe Articular Cartilage Damage

RM: Operative Images

Allograft insertionArticular Cartilage

Paste Grafting Repair

RM: Operative Images

High tibial opening wedge osteotomy

RM: 3.5 Years Post-Allograft

Movie

Primary Surgery Second Look, 3.5 years later

RM: Histology

RM: 3.5 Years Post Operative

Long-leg

RM: 5 Years Post Operative MRI

SagittalCoronal

RM: 6 Year Post Operative X-Ray

Long-leg

Lateral

Patient Example: HM

5-7o 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

HM

4 Yrs 9 Mo Post Paste Graft

Debrided lesion Healed paste graft

HM

4 Yrs 9 Mo Post Paste Graft

Biopsy Histology

Biologic Knee Replacement Revision Surgery

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)

TA: Preoperative MRI

• Tear at horn of medial meniscus• Osteoarthritis: medial compartment

SaggitalCoronal

4/22/02: Right medial meniscus rim before allograft

TA: Operative Images

TA: Meniscus Allograft Placement

A B MoviePreparation of medial

meniscal allograftPlacement of medial

meniscal allograftRelationship of lesion

to meniscus

TA: Injury

C

• Injury: 2 Mo. Post-op

• Swam in pool for 2 hours

• Developed immediate swelling

A Movie

TA: Revision

CA

Movie

Revision: 8 Months Post-allograft

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

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

RT: Pre-Op Imaging

• X-rays: Collapse of lateral joint space. Mild patellar spurring.

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

RT: Surgery 11/2009

• Lateral Meniscus Allograft transplantation

• Microfracture LFC and LTP (too far posterior for Articular Cartilage Paste Grafting)

• Removal of anvil osteophyte

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

RT: Revision Surgery

• Interval repositioning of the lateralmeniscus 5 days post index procedure.

• Re-microfracture of distal femoral condyleto ensure good blood clot.

RT: MRI 1 Day Post Revision

• Repositioned Lateral Meniscus Allograft

FSE T2 SAG FSE PD SAG

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.

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

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).

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

Conclusions

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

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

2009 Team

2005 Team