Upload
joie
View
99
Download
0
Tags:
Embed Size (px)
DESCRIPTION
Imperial college. St Mary’s hospital. Charing Cross Hospital. Meniscal and Anterior Cruciate ligament injuries. Chinmay Gupté PhD (Dip IC), FRCS (Tr&Orth), MA (Oxon), BMBCh Consultant Orthopaedic Surgeon/Senior Lecturer E Ali, Trauma Fellow A Dodds, SpR - PowerPoint PPT Presentation
Citation preview
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
9
• 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
14
Removal of meniscus: reduce surface area of contact>>>increased contact stresses
Does repair restore meniscal stress function???No long term studies
Meniscectomy consequences
15
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
24
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
28
ACL controversies
29
• 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
31
• 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?
33
Tibial Tunnel positions
34
Non anatomic Tunnel positions
35
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
36
Single vs double bundled
37
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
38
• 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
42
• 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
45
• Hamstrings vs BTB (Aglietti et al /Pinczewski et al)• Rehab: open vs closed chain• Multiligament
Conclusions
46
• 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