Meniscal and Anterior Cruciate ligament injuries

Chinmay GuptéPhD (Dip IC), FRCS (Tr&Orth), MA (Oxon), BMBChConsultant Orthopaedic Surgeon/Senior Lecturer

E Ali, Trauma FellowA Dodds, SpR

Imperial College Hospitals and Imperial College London

Imperial college Charing Cross Hospital

St Mary’s hospital

Competing interests

• none

What’s our agenda?

• Improve our practice• Enhance our knowledge• Address controversies• Cutting edge technologies/treatments

Summary

• Anatomy • Biomechanics• Meniscal tears: repair or resect?• Meniscal deficiency• ACL: what’s new?• (PCL)• Emerging technologies

Menisci

MenisciIntraarticular knee structures

Semi-lunar (axial)Wedge-shaped (coronal/saggital)Fibro-cartilaginous (type I Collagen)

MedialLateralAnterior

LateralMedialAnterior

Menisci anatomy

pMFL

aMFL

PCLLM

Anterior

Meniscal ligamentsInsertionalAnterior Intermensical (AIL)Mensicofemoral (MFLs)Deep Medial Collateral (dMCL)

Tibia

Femur

MedialdMCL

AIL

Lateral InsertionalLigaments

MFLs

Meniscal attachments

Histology1-3

Tissue bulk: circumferentialfibre bundles (Type I)Surface:Meshwork of thin fibrils/radial tie fibres

(Taken from: Petersen & Tillmann, 1998, Anat Embryol)

Histology and biomechanics

Tensile properties of intra-articular tissues (in MPa)

Tendon Ligament Meniscus(circumferential)

Labrum(circumferential)

Cartilage

500-700 300 110 30-60 2-201Petersen & Tillmann 1998, Anat Embryol2Bullough et al. 1970, JBJS-Br3Beaupre et al. 1986, CORR4Tissakht & Ahmed 1995, J Biomech

Meniscus functions

• Reduce contact stresses• Load spreaders• Shock absorbers• Stability• Lubrication• Proprioception• Nutrition

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• Axial load transferred through the joint is converted into meniscal hoop stresses

Tibia

Femur

The meniscusconforms to thefemoral condylesincreases its circumferencetranslates outwardsspreads the load overa large contact areahence reduces the stresses on the underlying cartilage

Insertional ligaments are key

70-99% of the joint load is carried by the menisci1

Load transmission

1Seedhom & Hargreaves, 1979, Eng Med

• Anchor menisci on tibial plateau• Control meniscal motion • Prevent excessive meniscal extrusion• Loss of one completely de-functions the meniscus• Tensile modulus in human1

MedialLateralAnterior

~ 165 MPa ~ 90 MPa

~ 75 MPa~ 90 MPa

Insertional ligaments

1Haut-Donahue & Hauch, July 2008, ESB

MFLs AIL dMCL

Occurrence 92% 1

(at least one MFL)75% 5-7 100%

Function Secondary restraints to posterior drawer2

??Significant anatomical

variability

Secondary restraint to valgus at 60-90° flexion8

Relation to meniscal function

MFL-deficiency results in 10% increase in contact

stresses3

Controls meniscal motion in conjunction with the insertional

ligaments (?)

Restrains excessive mobility of the medial

meniscus?? Contact stresses ??

Tensile properties

Modulus ~ 250 MPa4

i.e. similar to the major knee ligaments

??

1Gupte et al, 2003, Arthroscopy2Gupte et al, 2003, JBJS-Br3Amadi et al, 2008, KSSTA4Gupte et al, 2002, J.Biomech.

5Kohn & Moreno, 1995, Arthroscopy6Nelson & LaPrade, 2000, AJSM7Berlet & Fowler, 1998, AJSM8Robinson et al, 2006, AJSM

Meniscal “ligaments” stabilise knee

• Meniscectomy results in1-3 – Cartilage to cartilage contact– Less conformity– Decreased contact area– Increased contact stresses

(up to 200%)1

– Increased shear stresses

Intact Meniscectomised1Baratz et al, 1986, AJSM2Seedhom & Hargreaves, 1979, Eng Med3McDermott et al, 2008 KSSTA (Taken from: McDermott et al, 2008 KSSTA)

Total meniscetomy

Meniscetomy Stresses

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Removal of meniscus: reduce surface area of contact>>>increased contact stresses

Does repair restore meniscal stress function???No long term studies

Meniscectomy consequences

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Lateral meniscectomy results in OA; also probably medial

Late degenerative changes after meniscectomy. Factors affecting the knee after operation.PR Allen, RA Denham, and AV Swan.JBJS1984Chatain 2001 KSSTABrophy RH, Gill CS, Lyman S, et al. Effect of anterior cruciate ligament reconstruction and meniscectomy on length of career in National Football League athletes: A case control study. Am J Sports Med 2009;37:2102-2107.

• Circumferential– parallel to the load-bearing fibres– small effect on meniscal function

• Radial – Vertical – cut across the load-bearing fibres– large effect on meniscal function

• Flap• Bucket handle• Horizontal cleavage• Complex

Radial

Radial

Axial

Tear

CircumferentialMeniscal Tears

• Conservative• Repair• Partial meniscectomy• Total meniscectomy• Allograft transplantation• Implants (?)• Tissue engineering (?)

(Taken from: Arnoczky & Warren, 1983, AJSM)

Meniscal Tears: treatment options

• Complex tear repairs have poor outcomes

• Repair vs reconstruction results not clear cut (Shelbourne)

• Complications of repair:1. Chondral scuffing (Anderson)2. Hardware loose/Dart indentation3. Failed repairs lead to more meniscal loss4. Persistent pain5. Nerve damage

Meniscal Tears: “let’s repair them all”But:

Shelbourne, K.D. and D.R. Carr, Am J Sports Med, 2003. 31(5): p. 718-23. Meniscal repair compared with meniscectomy for bucket-handle medial meniscal tears in anterior cruciate ligament-reconstructed knees.Anderson Arthroscopy 2000; Austin AJSM 1993

Meniscal Repair Versus Partial Meniscectomy: A Systematic Review Comparing Reoperation Rates and Clinical Outcomes.

Paxton et alArthroscopy 2011

Resection Repair

Reoperation rate 3.9% 20.7%

Lysholm (functional) scores Lower (n=1) Higher

Radiographic degeneration More Less

Lower reoperation rate with repair after ACLR

“Whereas the combined reoperation rate after a partial meniscectomy is quite low, at 4%, the relatively high reoperation rate of almost 23% after meniscal repair may be acceptable if there is a potential long-term benefit to the joint. The lower reoperation rate of 14% after meniscus repair at the time of ACLR is even more likely to be acceptable assuming long-term benefit can be shown.”

Repair

Patient:<40 yrs

No comorbiditiesActivity level

BMI<30compliant

Tear:Red/white

<2cmLongitudinal/bucket

handle (not complex)<2months old

non-degenerateAssociated ACL reconstruction

Repair Technique

• Inside out is Gold standard:1. Large bucket handle especially posterior

portion2. Double barrelled guide3. Stryker retraction tool4. 2’0 suture eg ethibond5. Anterior to gastroc6. Watch saphenous nerve medially and

peroneal laterally

Technique

• All inside (Ultra fastfix):1. Better newer prostheses2. Portals slightly higher3. 1.4mm on stop4. Avoid scuffing5. Vertical sutures: radial tie fibres6. Curved needles7. 2up/1down

• White/white zone tear: younger/longitudinal/lateral/ACLR

• Rasping/trephining:stable/<1cm/partial tear

• Post op regime: NWB(Taken from: Arnoczky & Warren, 1983, AJSM)

Controversies

Trephining: Zhongman et a arthroscopy 1996;White on white: Gallagher et al knee 2010 and Noyes AJSM 2002

Meniscal replacement- artificial

• Products exists• Require 1. Stable rim of meniscal tissue2. suture

• ?normal mechanics• Menaflex: FDA approval

withdrawn 2010

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Meniscal transplant

• Normal articular cartilage• Technically demanding• Fixation issues:

either suture to capsuleOR bone plugs

• Sizing issues• ?normal mechanics• ?reduced degenerative change

25Marcacci et al AJSM 2012Verdonk et al JBJS A 2005 and 2006

Imperial Meniscus

Patent filedPolyurethaneUnique structureWear testingAnimal studiesFixation testing

Anterior Cruciate ligament

ACL established knowledge• Resists anterior drawer/pivot

shift• Double bundled functionally• ACL rupture >>> medial

meniscal tears• ACL reconstruction reduces

MM tear (Meunier Acta O Scand 1999)

• Mensical repair more successful with ACLR

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ACL controversies

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• Tunnel positions• Does ACLR obliterate Pivot shift?• Single vs double bundled• Extra articular reconstruction

Natural history of the unstable ACL deficient

The ACL Injury Cascade

ACL disruption

Subluxation Giving way

Meniscal injury Sports disability

Joint arthrosis

ACL bundles

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• AM bundle: tight in flexion (anterior drawer)

• PL bundle tight in extension (Lachmanns)

• PL bundle: further away for axis of rotation (resists pivot)

ACL Tunnel position: femur

32Harner JBJS A 2000

ACL Tunnel positions

• Femoral tunnel has become more oblique with time (more anatomic)

• Has this led to increased rerupture rate?

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Tibial Tunnel positions

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Non anatomic Tunnel positions

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Anatomic Non anatomic

Tunnel position• Ensure adequate notch clearance:

vertical PCL• Drill through medial portal (?view

accessory medial portal)• 10:00 (R) or 2:00 (L) position• Mark with chondral pick 70degrees• ?use offset guide/guide wire• 4.5mm solid drill• Ensure knee fully flexed• Tibia: 2/3rds along line from anterior

horn LM insertion to medial tibial spine

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Single vs double bundled

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Adachi et al JBJS 2004 RCT Single vs double no differenceMeredick metaanalysis AJSM 2008 no differenceYasuda Arthroscopy 2006 better but n=4Siebold Arthroscopy 2008: RCT DB better resultsHussein ..&Fu AJSM 2011 RCT 5 yr results DB better pivot but no functional difference

Double bundledMore anatomicGreater control of pivot (93% vs 67% Hussein et al)Better tunnel position

Single bundled:DB technically challengingNo better functional results with DBMore oblique SB just as goodDifferential failure of DB bundles

Pivot

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• Main functional problem in ACL rupture is the pivot phenomenon

• SB reconstruction does not obliterate pivot in 33% (Hussein 2011)

• Double bundled: Greater control of pivot (93%, Hussein)

• But more technically difficult/no functional benefit

• Is there any other way to deal with the pivot?

• Extraarticular augmentation of ACL reconstruction

Galway HR, Beaupre A, MacIntosh DL. Pivot shift: a clinical sign of symptomatic anterior cruciate insufficiency. J Bone Joint Surg. Br 1972;54:763-4.Zantop et al Arch Orth Trauma Surg 2010

Previous extra-articular reconstruction

• Used as an isolated technique and combined with intra-articular techniques.

• First description by Hey- Groves- 1920

• Several different methods popular:– Lemaire– MacIntosh– Ellison– Losee– Marcacci

MacIntosh reconstruction

Used strip of ITB- the ‘lateral substitution’ reconstruction

Marcacci RepairHamstring graft as intra-articular reconstruction with extra-articular augmentation

Extra articular reconstruction: poor historical results

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• Failure of isolated extraarticular reconstruction and recurrent instability (Dandy 1995)

• Degenerative change in the lateral compartment (Roth 1987; Strum 1989)

But…• Stretch of tenodesis in isolated

extraarticular or augmented with nonanatomic intraarticular placement

• Degenerative change from 4 weeks in plaster post op

• Newer rehab techniques and braces

Neyret et al: Extraarticular tenodesis in skiiers BJSM 1994

Can we do any better?• Understand anterolateral capsular

anatomy (Segond fracture)• Assess new procedures

biomechanically in vitro• A more ‘anatomic’ approach may

prevent some of the problems from the past:-– Reduce failure rates– Decrease risk of lateral

‘overtightening’– Minimally invasive techniques to

avoid large scars

Other issues in ACL

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• Hamstrings vs BTB (Aglietti et al /Pinczewski et al)• Rehab: open vs closed chain• Multiligament

Conclusions

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• Anatomy and basic biomechanics is key• Manage the patient not the book/paper

"He who studies medicine without books sails an uncharted sea, but he who studies medicine without patients does not go to sea at all." "Listen to your patient, he is telling you the diagnosis,"

Sir William Osler (1849-1919)

Individualised care no evidence base

Evidence based generic care

Evidence based individualised care