Review Article Meniscal and Chondral Pathology Associated ... · meniscal tears in acute injuries, but with advancing chronicity, medial meniscal tear rates increase while lateral

Dow

nloadedfrom

https://journals.lww.com

/jaaosby

k38zdtHxkv5R

00xx69XbFJ18sBObJ8H

5aDRoofIuQ

4ietseJnDGPIKXXR

4/esRsyqR

Hht5In6By/dU

pQ9lIncC

B79g7K0PL/8lcUsvSr+gW

a/H6bS4fBvTfuoAreG

jq3MXq+Q

eMtiP8=

on02/09/2019

Downloadedfromhttps://journals.lww.com/jaaosbyk38zdtHxkv5R00xx69XbFJ18sBObJ8H5aDRoofIuQ4ietseJnDGPIKXXR4/esRsyqRHht5In6By/dUpQ9lIncCB79g7K0PL/8lcUsvSr+gWa/H6bS4fBvTfuoAreGjq3MXq+QeMtiP8=on02/09/2019

Review Article

Meniscal and Chondral PathologyAssociated With Anterior CruciateLigament Injuries

Abstract

Anterior cruciate ligament (ACL) ruptures are commonly associatedwith meniscal and articular cartilage injuries, and the presence ofthese defects influences both short- and long-term outcomes.Multiplevariables are predictive of this pathology including time from injury,age, and sex. Revision ACL reconstructions demonstrate higher ratesof chondral injury than primary reconstructions. Menisci are importantsecondary stabilizers of the knee in the setting of ACL deficiency, andspecific tear types are more consistently associated with ACL injury.Successful outcomes with multiple treatment options for meniscaltears in conjunction with ACL reconstruction have been reported.Maintainingmeniscal integrity may be protective of both joint surfacesand graft stability in the long term; however, clear treatmentrecommendations for tear subtypes remain ill defined. High-gradechondral defects have the most consistent and potentially largestnegative effect on long-term patient-reported outcomes; however,optimal treatment is also controversial with successful resultsdemonstrated with several modalities including benign neglect.

Approximately 50% of primaryanterior cruciate ligament

(ACL) ruptures and over 90% offailed reconstructions will have co-existing cartilage and/or meniscalpathology.1-4 Multiple factors con-tribute to joint surface injury in asso-ciation with ACL tears, and theappropriate management of theseconcomitant lesions is an area ofongoing study. Recent literature hasprovided insight into the biomechan-ical interaction between the ACL andmeniscal structures, garnering animproved understanding of injurypatterns associated with ACL tears.Many studies have demonstrated anotable clinical association betweenchondral and meniscal pathology;however, optimal treatment of spe-cific lesions remains an area ofcontroversy.

Epidemiology

The incidence of associated cartilageand meniscal pathology with ACLtears varies widely in the literature.Recent studies suggest that betweenone and two thirds of patients willpresent with an associated meniscaltear in conjunction with a primaryACL rupture1,3,5,6 and that approx-imately one fourth of patients willhave combined medial and lateraltears.5 The rates of chondral injurieswith ACL ruptures are inconsistentlyreported because of variability ingrading and chronicity. Variation indefect classification also exists withthe Outerbridge and InternationalCartilage Restoration Society scalesmost commonly used. Regardless ofthe system used, virtually all studies

Andrew N. Pike, MD

Jeanne C. Patzkowski, MD

Craig R. Bottoni, MD

From the Department of OrthopaedicSurgery, Division of Sports Medicine,Tripler Army Medical Center,Honolulu, HI.

Dr. Bottoni or an immediate familymember is a member of a speakers’bureau or has made paidpresentations on behalf of Arthrex;serves as a paid consultant to Arthrex;and has received research orinstitutional support from Arthrex, andthe Musculoskeletal TransplantFoundation. Neither of the followingauthors nor any immediate familymember has received anything ofvalue from or has stock or stockoptions held in a commercial companyor institution related directly orindirectly to the subject of this article:Dr. Pike and Dr. Patzkowski.

J Am Acad Orthop Surg 2019;27:75-84

DOI: 10.5435/JAAOS-D-17-00670

Copyright 2018 by the AmericanAcademy of Orthopaedic Surgeons.

February 1, 2019, Vol 27, No 3 75

Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.

http://dx.doi.org/10.5435/JAAOS-D-17-00670

distinguish between “low-grade”(softening/fibrillations/slight fis-suring) versus “high-grade” (deepfissuring/exposed subchondral bone)lesions, which correlates with grades0 to 2 and 3 to 4 on either scale,respectively.2,3,6-8 A systematic reviewof ACL reconstructions performedwithin 3 months of injury reportedrates of chondral injury ranging from16% to 46%.7 However, high-gradedefects were the lowest in frequency(16%), and other studies have re-ported rates of high-grade lesions to beas low as 7% to 9% irrespective ofchronicity.2,8

Time from InjurySeveral large level II and III observa-tional studies have reported on thetiming of ACL reconstruction and theobserved incidence of associatedpathology1,3,5,9,10 (Table 1). Con-sistent findings include higher ratesof both meniscal and chondralpathology with increasing time frominitial injury to surgical reconstruc-tion and have led some authors toconclude that early ligamentousstabilization may prevent secondarydamage to the joint.3,11 A large levelII prospective cohort found thatsurgical delay increased rates ofmeniscal tears and chondral lesionsby 1% per month and that the

presence of a meniscal tear doubledthe likelihood of an associatedarticular cartilage defect.3 Addi-tional studies have reported thatmedial meniscal tears are most proneto secondary injury with increasingtime from surgery.1,2,9,12 A delay aslittle as 6 to 12 weeks from point ofinjury has been shown to markedlyincrease the rate of medial meniscaltears (8% to 19%), whereas delaysof greater than 1-year result inincreased number, size, and grade ofchondral defects.1,5 Previous reportshave cited higher rates of lateralmeniscal tears in acute injuries, butwith advancing chronicity, medialmeniscal tear rates increase whilelateral meniscal tears remain rela-tively constant.1,12 Of note, the au-thors’ definition of “chronicity” wasbased on the occurrence of second-ary episodes of instability and notspecific time intervals. Recent liter-ature has also supported this obser-vation with the increasing number ofpatient-reported instability episodeshaving the highest association withthe risk of secondary medial me-niscal tears but no association withlateral meniscal tears.1

Patient Specific VariablesPatient demographics also influencethe type and degree of associated

pathology with ACL injuries. Suchvariables includeageand sex (Table 1)as well as body mass index andsport participation. Several studieshave reported on increasing age as arisk factor for medial meniscal tearsand chondral defects; however, au-thors have also observed the positiveassociation between age and surgicaldelay, which likely contributes tothis finding.5,9 However, in studiesthat specifically evaluate grades ofchondral defects, older patients, onaverage, have higher-grade lesionsthan younger patients.3,5,10 Malesconsistently demonstrate higher ratesof meniscal tears than females.1,3,5,9,10

Although less frequently reported,obesity has been associated withhigher rates of chondral defects (oddsratio [OR], 2.63; CI, 1.10 to 6.28).1

Sport participation is less clear withsome reports finding no increased riskfor chondral or meniscal pathology.1

However, using soccer as a referent asthe most common sport associatedwith ACL tears, a large multinationalcohort observed basketball to havesignificantly higher rates of lateralmeniscal tears (OR, 1.28; CI, 1.06to 154), chondral defects (OR, 1.23;CI, 1.01 to 1.51), and combinedmeniscal/chondral lesions (OR, 1.38;CI, 1.11 to 1.72)13 and men’s teamhandball to have an increased riskfor lateral meniscal tears (OR, 1.27;

Table 1

Variables Associated With Chondral and Meniscal Pathology in Primary Anterior Cruciate Ligament Tears

Factor Level of Evidence Patients Time From Injury Increasing Age Male Sex

Granan et al3 2 3,475 CD CD MT

— — MT — —

Slauterbeck et al5 2 1,104 MMT: .3 mo MMT, CD (MFC) MMT, LMT, CD

— — MMT/LMT/CD: .12 mo — —

Chhadia et al9 3 1,252 MMT, CD: .12 mo CD LMT, CD

Røtterud et al10,a 2 15,783 CD: .12 mo CD CD

Kluczynski et al1,b 3 541 MMT CD LMT, MMT

BMI = body mass index, CD = chondral defect, LMT = lateral meniscal tear, MFC = medial femoral condyle, MT = meniscal tear side unspecified,MMT = medial meniscal teara Grade 3, 4 CD; no MT reported.b Linear association with an increasing number of instability episodes up to 5.

Meniscal/Chondral Injuries in Anterior Cruciate Ligament Tears

76 Journal of the American Academy of Orthopaedic Surgeons


CI, 1.10 to 1.48) and high-gradechondral defects (OR, 2.36; CI, 1.33to 4.19).10,13

Failed ReconstructionsRecurrent knee instability secondaryto a failed ACL reconstruction oftenresults in progression of secondaryinjury patterns with rates exceedingthose of primary reconstruction. Theincidence of meniscal tears is as highas 75% and chondral injuries 67%,with over 90% of patients presentingwith either lesion type.4,14 In a level II

study comparing 508 primary with281 revision ACL reconstructions,the revision cases had a significantlyhigher incidence of high-grade de-fects involving the lateral femoralcondyle (OR, 1.73; CI, 1.02 to 2.93;P = 0.04) and patellofemoral com-partment (OR, 1.70; CI, 1.01 to2.84; P = 0.04) irrespective of me-niscal status. However, rates of lat-eral meniscal tears were lower in therevision group (OR, 0.54; CI, 0.39 to0.75; P , 0.01), whereas medialmeniscal tear rates were similar.15

Additionally, high-grade chondral

defects were associated with previ-ous partial meniscectomies of thecorresponding compartment regard-less of primary or revision status.Similarly, a level II cohort evaluating725 revision ACL reconstructionsfound that a previous meniscectomywas associatedwith a grade 2 or higherdefect in any compartment includingpatellofemoral (P , 0.0001).14 Fur-thermore, after adjusting for age, par-tial meniscectomies resulted in higherrates of chondral injury comparedwith normal menisci (P, 0.0001) orprevious meniscal repairs in either

Table 2

Patient-reported Outcomes Based on Combined Chondral/Meniscal Pathology/Treatment

FactorLevel ofEvidence

Patients (MeanAge and

Follow-up) (yr) Lateral Meniscal TearMedial Meniscal

TearChondral Defects

(Grade 3, 4)

Shelbourneet al11

3 928 (23, 8.6) Worse outcomes:partial lateralmeniscectomy:(IKDC)

Worse outcomes:partial medialmeniscectomy:(IKDC)

Worse outcomes: alllocations: (IKDC)

Røtterudet al2

2 8,4762,30 No statisticallysignificant findings

No statisticallysignificant findings

Worse outcomes: allsizes, locationunspecified (KOOS-all subscales)

Cox et al6,a 1 1,3076,23 Improved outcomes:nontreatment: (IKDC,KOOS-all subscales)& .50% lateralmeniscectomy:(IKDC, KOOS-symptoms/activity)

Improved outcomes:.50% medialmeniscectomy:(KOOS-pain)

Worse outcomes: MFC,LFC, MTP: (IKDC),MFC, LFC, MTP, LTP,trochlea: (KOOS-multiple subscales) &MFC (Grade 4 only):(Marx-K)

— — — Worse outcomes:,33% medialmeniscectomy:(IKDC); medialmeniscal repair:(IKDC, KOOS)

—

Dunnet al38,a

1 1,4116,23 Improved outcomes:nontreatment&.50%lateral meniscectomy(SF-36)

No statisticallysignificant findings

Worse outcomes: LTP(SF-36)

MARSgroup4,b

2 9892,26 Worse outcomes:previous partial lateralmeniscectomy (IKDC,KOOS/WOMAC-allsubscales)

Worse outcomes:previous partialmedial meniscectomy(KOOS-symptoms,pain, WOMAC-stiffness)

Worse outcomes:trochlea (IKDC,KOOS/WOMAC-6/8subscales), all otherlocations-varioussubscales

IKDC = International Knee Documentation Committee, KOOS = Knee injury and Osteoarthritis Outcome Score, LFC = lateral femoral condyle, LTP =lateral tibial plateau, MFC = medial femoral condyle, MTP = medial tibial plateau, SF-36 = short-form 36, PCS = physical component summarya Separate reports on the same patient population.b Revision data.

Andrew N. Pike, MD, et al

February 1, 2019, Vol 27, No 3 77


compartment (P = 0.003) althoughlateral meniscal repairs were moreprotective of their respective articularsurfaces than medial meniscal repairs(P = 0.03). In a large level II studycomparing 989 patients undergoingrevision reconstruction with their re-spective primary reconstruction find-ings, rates of medial meniscal tearsincreased slightly, 38% to 45%, andlateral meniscal tears increased 20% to37%. A complete analysis of chondrallesions was limited by the lack of pri-mary data; however, at the time ofrevision, 43% of patients had at leastgrade 2 changes of the medial femoralcondyle, 29% lateral femoral condyle,30% patellar, and 20% trochlear.4

These studies suggest that although theoverall rates of chondral injury arehigher in revision cases, intact or pre-served menisci at the time of primaryreconstruction may decrease the inci-dence of associated chondral lesionsobserved in failed reconstructions. Ad-ditionally, patellofemoral chondrosis ismarkedly more likely to develop inpatients undergoing revision than inprimary cases.

Meniscal Tears

BiomechanicsInterest in the mechanism of injurywith ACL tears and the associatedstress imparted to supporting struc-tures has led to several cadaver studiesevaluating the role of the menisci inknee stability. The effect of to-tal meniscectomies in the settingof ACL deficiency was assessed withsimulated pivot shift and Lachmanmaneuvers.16 A total medialmeniscectomy resulted in markedlyincreased anterior tibial translationwith Lachman maneuvers (11.4 65.2 versus 5.96 3.1 mm; P, 0.001)compared with an ACL tear alone,but no notable difference with pivotshift. Conversely, a total lateralmeniscectomy resulted in significantlyhigher tibial translation with pivot shift

(19.06 4.6 versus 13.96 4.3mm;P,0.05) and not Lachman maneuvers.Although total meniscectomies arerelatively uncommon, the study dem-onstrates the roles of the medial andlateral menisci in anterior and rotatorystability, respectively.Additional laboratory investigations

have evaluated specific tear types withsimilar findings. The effects of periph-eral longitudinal posterior hornmedialmeniscal tears (mean 28 mm lengthtear) in the setting of ACL deficiencywere evaluated.17 Findings includedsignificant increases in anterior trans-lation with simulated Lachman ma-neuvers at flexion angles up to 60�(P , 0.05) but no differences withpivot shift. Furthermore, the periph-eral tear resulted in the same degreeof instability as a total medialmeniscectomy. After meniscal repair,however, stability was restored to theisolated ACL-deficient state. A similarcadaver study evaluated the effectof a posteromedial meniscocapsulardefect with ACL insufficiency.18

Maximal anterior translation (mean,14 mm; P , 0.001) occurred withsimulated Lachman maneuvers at30� flexion in knees with a postero-medial meniscocapsular lesion. Repair(arthroscopic, all-inside) of themeniscocapsular defect restoredtranslation to that of the isolatedACL-deficient state (mean, 10.1 mm;P = 001). After patellar tendon liga-ment reconstruction, stability wasfurther improved to 4.1 mm but wasthen destabilized to 7.1 mm with re-sectioning of the meniscocapsularrepair (P = 0.01). These studies suggestthat the peripheral, posteromedialmeniscal complex contributes mark-edly to the anteroposterior stability ofthe knee in the ACL-deficient state.The effect on stability of postero-

lateral root avulsions with ACL tearshas also been studied. A cadaverinvestigation evaluated simulatedpivot shift and anterior tibial trans-lational forces at varying degrees ofknee flexion before and after arthro-

scopically creating a posterolateralroot tear (including disruption ofmeniscofemoral ligaments). Progres-sive increases in tibial translationwith pivot shift was noted from ACLintact (2.62 6 0.53 mm), to ACLresection (6.01 6 0.51 mm; P =0.0005), and to ACL resection/roottear (8.13 6 0.75 mm; P , 0.0001).However, the root tear did notchange stability with simulatedLachman maneuvers.19 In a similarstudy, isolated root tears with andwithout meniscofemoral attachmentresections were assessed in cadaverknees with simulated pivot shift,internal rotation stress, and anteriordrawer all at varying degrees of kneeflexion. The authors found a statis-tically significant 1-mm (P , 0.05)increase in anterior tibial translationduring pivot-shift testing at 20� and30� with combined ACL/lateralmeniscal root tears compared withisolated ACL deficiency. Conversely,the authors found a statistically sig-nificant 1.1-mm (P , 0.05) increasein anterior translation with anteriordrawer at 30� and 60� between thesegroups. Furthermore, the lateralmeniscal root insertion seemed toprotect against excess internal rota-tion at higher degrees of knee flexionregardless of ACL status. The au-thors concluded that injury to theposterolateral root insertion mayresult in higher-grade pivot-shift find-ings clinically and meniscofemoralligament status further contributes torotational stability.20

Tear SubtypesSpecific tear patterns are oftenobserved in conjunction with ACLruptures. Variables include the loca-tion and orientation of tears, as wellas injury to capsular and root at-tachments. In terms of location, 95%and 77% of medial and lateralmenisci, respectively, involve theposterior horn.1 More specifically,the peripheral and central zones of




the posterior horns are the mostcommon locations of tears, inde-pendent of age or injury chronicity.5

However, these zone-specific datafail to report on root and capsularattachments, specifically. In terms oforientation, posterior vertical, lon-gitudinal tears are commonly reportedacutely, with degenerative and hori-zontal patterns becoming more prev-alent in chronic cases.21-24 Unstablebucket-handle morphology is alsocommonly recognized. In review ofover 2,000 ACL reconstructions, therates of medial and lateral bucket-handle tears were 7% and 23%,respectively.22,23

A more recently investigated tearpattern is the aforementioned postero-medial meniscocapsular defect, or“ramp” lesion25 (Figure 1). Thepathoanatomy is not entirely clearand possibly includes disruption ofmeniscotibial ligament attachments.26

Authors have observed that this is anunderappreciated lesion with MRIsensitivity in detecting ramp lesionsranging widely, 0% to 77%.25 Twoseparate studies have reported anincidence of approximately 17% forramp lesions in association withACL tears.26,27 In a consecutiveseries of 302 patients, investigatorsfound an overall 41% rate of medialmeniscal disruptions, of which 40%of these were ramp lesions (50/302;16.6%). Of these capsular defects,23% were diagnosed viewing throughthe intercondylar notch, and anadditional 17% required utilizationof a posteromedial portal—7% over-all rate of “hidden” lesions.26 Al-though the overall incidence of medialmeniscal tears increases with chronic-ity, the rates of ramp lesions withsurgical delay are less clear with someauthors suggesting no increased inci-dence beyond 6 weeks from the timeof injury,26 whereas other reportsobserve increasing prevalence up to24 months after injury.27 Further-more, young males seem to sustain thehighest rates of ramp tears.27

As mentioned previously, there isalso increasing interest in the con-tributions of the posterolateralmeniscal root attachments in theACL-deficient knee. Association ofthis injury in conjunction with ACLtears is approximately 8% to 14%.20

Conversely, posteromedial meniscalroot avulsions are uncommonlyobserved with isolated ACL injury,although they have increased asso-ciation with multiligament injuries,particularly those involving completemedial collateral ligament ruptures.28

TreatmentThe diversity of meniscal tear patternsencountered in the ACL-deficient kneeadds complexity to the treatmentdecision-making process, and ques-tions still exist regarding the optimalstrategies for maximizing outcomes.Treatment options for meniscal tearsencountered during ACL reconstruc-tion include débridement, abrasion/trephination, repair, and benignneglect. Acceptable outcomes havebeen reported with each of these op-tions; however, high-level compara-tive studies are lacking. In revisioncases with substantial meniscal defi-ciency, allograft transplantation maybe considered to improve both stabil-ity and chondral protection, but fur-ther discussion is beyond the scope ofthis review.Several authors have suggested that

stable tear patterns are effectivelytreated with minimal or no interven-tion.21,24,29,30 Although the exactdefinition of a “stable”meniscal tearis somewhat ambiguous, commondescriptors often include: non-degenerative, nondisplaceable, incom-plete, peripheral, longitudinal, and/orlength less than 10 to 15 mm.21,24,29,30

A recent level IV systematic reviewevaluated the results of benign neglectof stable meniscal tears during ACLreconstruction.Of 646 tears left in situ,the overall rate of revision surgery was5.4%. However, medial meniscal tears

had higher rates of revision surgery(9.5%) compared with lateral (3%).24

A level III reviewwith 6-year follow-upof 208 meniscal tears left in situ withACL reconstruction found that 97.8%and 94.4% of lateral and medial tearsrequired no further intervention,respectively. Risk factors for failureincluded younger patient age (18.6versus 25.1; P = 0.26) and tearlength .10 mm (11.5% versus 3.2%;P = 0.35).30 All failures laterally weregreater than 10 mm in length; how-ever, 1/3 of medial failures were,10 mm. A level III case control studyassessed patients undergoing trephi-nation of a stable, peripheral medialmeniscal tear during ACL recon-struction.21 At mean 5-year follow-up, no differences were observedin subjective patient outcomes orradiographic grading compared withnontear controls. However, the tearcohort had a significantly higher rateof revision surgery (16.3% versus5.8%; P , 0.0001). A level II pro-spective randomized study comparedtrephination/abrasion versus repairof stable (11 to 14 mm) postero-medial meniscocapsular lesions in 73patients. At minimum 2-year follow-up, no differences were found inpatient-reported outcomes, objectivestability, or healing rates on follow-up MRI (92% completely healed).29

Long-term clinical outcomes ofunstable ramp lesions left in situ arelacking; however, aforementioned

Figure 1

Seventy degrees arthroscopic viewthrough the intercondylar notch of aposteromedial meniscocapsularseparation or “ramp” lesion.


February 1, 2019, Vol 27, No 3 79


biomechanical data suggest a potentialdetrimental effect on long-termstability.Approximately20%to30%ofACL

reconstructions include an associatedmeniscal repair.31 Despite this, noprospective randomized studies havecompared treatments/techniques in-volving unstable meniscal tear pat-terns with ACL reconstruction. In alevel IV meta-analysis including 21studies and 1,126 patients, failurerates of all-inside meniscal repairswere significantly higher than inside-out (16% versus 10%; P = 0.016)despite shorter mean follow-up times(58 versus 76 months).31 Implant-related complications were also sig-nificantly higher with all-insidedevices. The authors proposed thatthe inside-out technique be the currentbenchmark with ACL reconstructionbut acknowledged the need for long-term randomized studies with modernimplants. A large level II cohort of4,691 patients with 2-year follow-upfound that only medial meniscal re-pairs had significantly worse Kneeinjury and Osteoarthritis OutcomeScore (KOOS) subscales comparedwith isolated ACL reconstructions(Symptoms: b = 22.5; CI, 24.6to 20.5; P = 0.023, Quality of Life:b =23.8; CI,26.8 to21; P = 0.009).However, all other treatments had noeffect, including any lateral meniscalintervention.32 The authors hypoth-esized that the respective negativeand positive effects of partialmeniscectomies and repairs may notbe evident with relatively short follow-up. In terms of large, unstable tearpatterns, a comparison of inside-outrepair versus débridement of bucket-handle tears in patients withoutchondral damage has been evaluatedwith nonrandomized level III evidence.Lateral tears were repaired more fre-quently (74% versus 36%) because ofhigher rates of degenerative findingsmedially. In both groups, subjectiveoutcomes (International Knee Doc-umentation Committee [IKDC]) were

similar at 7 and 9-year follow-up,respectively. Pain scores were slightlyworse with partial lateral meniscec-tomies compared with repairs (P =0.0478). Of all treatments, the worstoverall outcomes were in patients withdegenerative medial tears that wererepaired (P = 0.02). However, theoverall clinical success rates for repairof nondegenerative tears exceeded97% in both compartments.22,23

Treatment of posterolateral rootavulsions in conjunction with ACLreconstructions remains unclear.Some investigators have recommendedrepair based on the known biome-chanical effect of these injuries in rela-tion to knee stability;19,20,28 however,clinical data supporting this are lim-ited. Although high-powered studiesare lacking, a single level III investi-gation evaluating 33 patients ata mean follow-up of 10.6 yearsdemonstrated no significant differencein IKDC scores compared with amatched control group (84.6 6 14versus 90.56 13; P = 0.09). However,the avulsion cohort had increasedlateral compartment joint space nar-rowing radiographically (1.0 6 1.6versus 0 6 1.1 mm; P , 0.006).33

Markedly unstable root tears maybe repaired with transosseous su-tures (Figure 2).High-level clinical evidence on the

effect of meniscal integrity on post-operative stability is also lacking.One level III review of 482 patients atmean7.6 years postoperatively foundsignificantly higher KT-1000 side-to-side differences in patients with anymedial meniscal resection comparedwith intact medial menisci (2.66 1.7versus 2.0 6 1.5 mm; P = 0.0065),but no differences in graft failureswere reported.11 In a recent level IIIstudy with median follow-up26 months, 118 patients were eval-uated after anatomic single bundlehamstring tendon autograft ACLreconstruction. The investigatorsfound that medial and lateral me-niscal deficiency were the highest

risk factors for graft failure (medial:hazard ratio, 15.1; CI, 4.7 to 48.5;P, 0.001, lateral: hazard ratio, 9.9,CI, 3 to 33; P , 0.001).34

Chondral Defects

Natural HistoryArticular cartilage injury associatedwith ACL reconstruction possiblyhas the greatest single effect on long-term subjective outcomes.11 How-ever, compared with meniscalpathology, the volume of literaturefocused on treatment of chondraldefects in conjunction with ACLreconstruction is significantly infe-rior. The medial femoral condyle isthe most common location reportedoverall; however, lateral femoralcondyle defects are also reported inboth acute and chronic cases5-7

(Figure 3). In a large, level-III reviewof 2,770 patients, 4.5% were foundto have an isolated high-gradechondral defect (treated withbenign neglect, mean size 1.7 cm2) inthe absence of meniscal pathology.Compared with a cohort withoutmeniscal or chondral pathology, atmean follow-up 8.7 years, IKDCscores were statistically lower butdifferences were likely not clinicallysignificant (medial: 1.2; P = 0.0451,lateral: 3.1; P = 0.0047).35 A similarstudy also compared untreated high-grade defects (mean size 2.1 cm2) at10- and 15-year follow-up with amatched control group. Findingsincluded no subjective difference at10 years and statistically, but again,not likely clinically significant, lowertotal IKDC scores at 15 years (79.6versus 83.7; P = 0.031).8

Bone contusion patterns have longbeen recognized in association withACL injury with questionable long-term effect on articular cartilage.The most common location for thisfinding is the lateral tibial plateaufollowed by the lateral femoralcondyle.36 A recent review found no




correlation between severity or vol-ume of bony contusions with clinicaloutcomes after ACL reconstruction.However, 21% of lateral contusionswere associated with a “clinicallysignificant” chondral defect (definedas Outerbridge $2) and resulted inmarkedly worse outcomes at allmeasured time points (Figure 4).Notably, patients with these defectswere on average older (33.9 versus26.4 years) and heavier (body massindex, 27.8 versus 24.3) than iso-lated contusion patients.36

Repair TechniquesHigh-level studies evaluating ACLreconstruction with concurrent car-tilage repair are lacking. Techniquesdescribed include chondroplasty,microfracture, autologous chondrocyteimplantation, and osteochondralautograft/allograft transplantation.Reviews consistently report suc-cessful outcomes; however, most ofthese studies are level IV caseseries.7 In a level II, nonrandomizedcomparison of microfracture,débridement, or benign neglect offull-thickness cartilage defects in 357patients (mean age, 36) at the time ofACL reconstruction, the authorsnoted at 2-year follow-up that KOOSsubscales of Sports/Recreation andQuality of Life were significantlylower with microfracture (b = 28.6;95% CI, 216.4 to 20.7, andb = 27.2; 95% CI, 213.6 to 20.8)regardless of age, defect size, orassociated meniscal pathology. Nonotable difference between débride-ment and benign neglect was found.37

A prospective, randomized level II(nonblinded) study comparing os-teochondral autograft transplanta-tion, microfracture, and débridementof high-grade defects (mean, 2.6 cm2)in conjunction with ACL recon-struction found at mean 36-monthfollow-up superior results withosteochondral autograft transplan-tation compared with microfracture

Figure 2

Unstable lateral meniscal root tear, displaced into joint space (A). Root securedwith racking stitch (B). Drill guide used to create a docking tunnel for repair (C).Final repair with sutures secured through the tibia (D).

Figure 3

Massive lateral femoral condyle chondral defect associated with an acuteanterior cruciate ligament tear with a fragment displaced into posterior jointspace (A and B). Arthroscopic view of large full-thickness chondral loss (C).Retrieval of loose body through intercondylar notch (D).


February 1, 2019, Vol 27, No 3 81


(P = 0.024) or débridement (P =0.018).39 No difference betweenmicrofracture and débridement wasnoted, although all modalities wereinferior to a control group with in-tact articular cartilage.

Clinical Implications

Several studies have attempted toqualify patient outcomes after ACLreconstruction based on multiplepatient and pathologic variables,including the presence of meniscaland chondral lesions (Table 3).Scandinavian population-based stud-ies provide the greatest patientnumbers; however, they have rela-tively poor follow-up and providelimited details of treatment. Onesuch study with 54% follow-upreported 2-year outcomes based onmeniscal and chondral pathology.Only the presence of high-gradechondral defects was associatedwith worse KOOS outcomes at 2years, although a subanalysis basedon meniscal tear treatment was notperformed.2 Two level I prospectiveinvestigations, both reporting ondata from the same pool of patientswith 6-year follow-up, found, com-pared with uninjured menisci, worsepatient-reported outcomes with

medial meniscal repairs and im-proved outcomes with nontreatmentof lateral meniscal tears.6,38 Addi-tionally, repair or resecting morethan 50% of the lateral meniscusresulted in improved quality of lifeand activity scores, whereas resect-ing more than 50% of the medialmeniscus improved pain scores.6

Currently, an explanation for theobservation of improved outcomesin both nontreatment of lateral me-niscal tears or large resections ofeither meniscus is lacking. In the samestudies, the presence of chondraldefects negatively affected outcomesbut varied based on the defect loca-tion. A level-III review with longermean follow-up of 8.6 years foundthat both meniscal resections andchondral defects were associatedwith worse subjective outcomes.11

Data from revision reconstructionsdemonstrate similar findings withpreviousmeniscectomies and chondraldefects, particularly trochlear, neg-atively affecting outcomes at 2-yearfollow-up.4

Figure 4

Sixteen-year-old man with a typicallateral bony contusion patternassociated with pivot-shift mechanismin anterior cruciate ligament injury. Ofnote, an associated subchondralimpaction injury is noted posterior tothe sulcus terminalis.

Table 3

Summary of Conclusions (Levels of Evidence)

Lateral meniscal tears are more often associated with acute, primary ACL tears and occur less frequently in chronic ACLtears and failed reconstructions (III)

Increasing time from injury and increasing episodes of instability result in higher rates of chondral defects and medialmeniscal tears (II, III)

Meniscal tears and previous partial meniscectomies have higher associations with corresponding compartmental chondraldefects in both primary and revision ACL reconstructions (II)

Failed ACL reconstructions have higher rates of chondral injury than primary cases, which partially depends on meniscalintegrity. Rates of patellofemoral chondrosis are higher in revision cases (II)

Benign neglect of stable meniscal tears in association with ACL reconstruction leads to generally acceptable outcomes;however, medial meniscal tears left in situ are associated with higher revision surgery rates than lateral tears (9.5%-16.3%versus 3.0%-5.8%).3,4 Detailed outcomes comparing treatment modalities in specific tear subtypes are generally lacking.

Success rates for repair of unstable, nondegenerative meniscal tears is high, with better survival rates with inside-outtechniques compared with all-inside techniques (III, IV)

Emerging biomechanical and clinical data suggest that meniscal deficiency negatively affects graft integrity after ACLreconstruction; however, this area needs further long-term clinical validation (III, IV)

Successful patient-reported outcomes have been demonstrated with multiple treatment modalities for chondral defects,4 aswell as benign neglect,3 when performed in conjunction with ACL reconstruction. However, the current level of evidenceand volume of literature are insufficient for clear treatment recommendations (II)

The presence of chondral defects consistently results in lower intermediate-to-long-term patient-reported outcomes. Lateralmeniscal tears in general have less negative effect on outcomes than do medial meniscal tears. (I, II)

ACL = anterior cruciate ligament




Summary

Optimizing long-term outcomes intreating ACL tears with associatedchondral and meniscal pathologyrequires an understanding of boththe natural history of specificpathology and the results of varioustreatment modalities. Despite in-sights gained from numerous studieson this subject, the complex, multi-factorial nature of this pathologyresults in continued managementquestions. The presence of high-gradechondral defects is consistentlyassociated with worse patient-reported outcomes.2,6,11,39 How-ever, intact menisci may lessen thiseffect, and a clearly superior treat-ment modality of these defects islacking, with benign neglectremaining a viable option.8,35 Re-sults related to meniscal tear typesand treatment are also unclear, andfurther high-level studies are neededregarding specific tear subtypes,modern repair techniques, the effectof tears, and/or insufficiency onlong-term stability. Existing datasuggest that lateral meniscal tears ingeneral may have acceptable resultsobtained with both aggressive andconservative treatment modalities inprimary reconstructions,6,32,33,39

whereas medial meniscal tears maybe more prone to relatively inferioroutcomes and/or higher rates ofrevision surgery regardless of treat-ment modality.6,21,25,30,32,39 How-ever, in revision cases, previouslateral or medial meniscal resectionsare associated with higher rates ofchondral injury and worse overalloutcomes due in part to increasedpatellofemoral involvement.4,14,15

Despite these observations, furtherstudy is needed to elucidate thecomplex factors involved in opti-mizing patient outcomes in the set-ting of ACL insufficiency withconcomitant meniscal or chondralinjury.

References

Evidence-based Medicine: Levels ofevidence are described in the table ofcontents. In this article, references 6and 38 are level I studies. References2, 3, 4, 5, 10, 14, 15, 29, 37, and 39are level II studies. References 1, 8, 9,13, 21, 22, 23, 27, 30, 32, 33, 34, 35,and 36 are level III studies. Refer-ences 7, 11, 12, and 26 are level IVstudies.

References printed in bold type arethose published within the past 5years.

1. Kluczynski MA, Marzo JM, Bisson LJ:Factors associated with meniscal tears andchondral lesions in patients undergoinganterior cruciate ligament reconstruction: Aprospective study. Am J Sports Med 2013;41:2759-2765.

2. Røtterud JH, Sivertsen EA, Forssblad M,Engebretsen L, Arøen A: Effect ofmeniscal and focal cartilage lesions onpatient-reported outcome after anteriorcruciate ligament reconstruction: Anationwide cohort study from Norwayand Sweden of 8476 patients with 2-yearfollow-up. Am J Sports Med 2013;41:535-543.

3. Granan LP, Bahr R, Lie SA, Engebretsen L:Timing of anterior cruciate ligamentreconstructive surgery and risk of cartilagelesions and meniscal tears: A cohort studybased on the Norwegian National KneeLigament Registry. Am J Sports Med 2009;37:955-961.

4. MARS Group: Meniscal and articularcartilage predictors of clinical outcome afterrevision anterior cruciate ligamentreconstruction. Am J Sports Med 2016;44:1671-1679.

5. Slauterbeck JR, Kousa P, Clifton BC, et al:Geographic mapping of meniscus andcartilage lesions associated with anteriorcruciate ligament injuries. J Bone Joint SurgAm 2009;91:2094-2103.

6. Cox CL, Huston LJ, Dunn WR, et al: Arearticular cartilage lesions and meniscustears predictive of IKDC, KOOS, and Marxactivity level outcomes after anteriorcruciate ligament reconstruction? A 6-yearmulticenter cohort study. Am J Sports Med2014;42:1058-1067.

7. Brophy RH, Zeltser D, Wright RW,Flanigan D: Anterior cruciate ligamentreconstruction and concomitant articularcartilage injury: Incidence and treatment.Arthroscopy 2010;26:112-120.

8. Widuchowski W, Widuchowski J, Koczy B,Szyluk K: Untreated asymptomatic deepcartilage lesions associated with anteriorcruciate ligament injury: Results at 10- and15-year follow-up. Am J Sports Med 2009;37:688-692.

9. Chhadia AM, Inacio MC, Maletis GB,Csintalan RP, Davis BR, Funahashi TT: Aremeniscus and cartilage injuries related totime to anterior cruciate ligamentreconstruction? Am J Sports Med 2011;39:1894-1899.

10. Røtterud JH, Sivertsen EA, Forssblad M,Engebretsen L, Arøen A: Effect of genderand sports on the risk of full-thicknessarticular cartilage lesions in anteriorcruciate ligament-injured knees: Anationwide cohort study from Sweden andNorway of 15 783 patients. Am J SportsMed 2011;39:1387-1394.

11. Shelbourne KD, Gray T: Results of anteriorcruciate ligament reconstruction based onmeniscus and articular cartilage status atthe time of surgery: Five- to fifteen-yearevaluations. Am J Sports Med 2000;28:446-452.

12. Shelbourne KD, Gray T: Anterior cruciateligament reconstruction with autogenouspatellar tendon graft followed byaccelerated rehabilitation: A two to nineyear follow-up. Am J Sports Med 1997;25:786-795.

13. Granan LP, Inacio MC, Maletis GB,Funahashi TT, Engebretsen L: Sport-specific injury pattern recorded duringanterior cruciate ligament reconstruction.Am J Sports Med 2013;41:2814-2818.

14. Brophy RH, Wright RW, David TS, et al:Association between previous meniscalsurgery and the incidence of chondrallesions at revision anterior cruciateligament reconstruction. Am J Sports Med2012;40:808-814.

15. Borchers JR, Kaeding CC, Pedroza AD,Huston LJ, Spindler KP, Wright RW;MOON Consortium and the MARSGroup. Intra-articular findings in primaryand revision anterior cruciate ligamentreconstruction surgery: A comparison ofthe MOON and MARS study groups. Am JSports Med 2011;39:1889-1893.

16. Musahl V, Citak M, O’Loughlin PF, ChoiD, Bedi A, Pearle AD: The effect of medialversus lateral meniscectomy on the stabilityof the anterior cruciate ligament-deficientknee. Am J Sports Med 2010;38:1591-1597.

17. Ahn JH, Bae TS, Kang KS, Kang SY, LeeSH: Longitudinal tear of the medialmeniscus posterior horn in the anteriorcruciate ligament-deficient kneesignificantly influences anterior stability.Am J Sports Med 2011;39:2187-2193.

18. Stephen JM, Halewood C, Kittl C, BollenSR, Williams A, Amis AA: Posteromedialmeniscocapsular lesions increase


February 1, 2019, Vol 27, No 3 83


tibiofemoral joint laxity with anteriorcruciate ligament deficiency, and theirrepair reduces laxity. Am J Sports Med2016;44:400-408.

19. Shybut TB, Vega CE, Haddad J, et al: Effectof lateral meniscal root tear on the stabilityof the anterior cruciate ligament-deficientknee. Am J Sports Med 2015;43:905-911.

20. Frank JM, Moatshe G, Brady AW, et al:Lateral meniscus posterior root andmeniscofemoral ligaments as stabilizingstructures in the ACL-deficient knee: Abiomechanical study. Orthop J Sports Med2017;5.

21. Shelbourne KD, Benner RW, Nixon RA,Gray T: Evaluation of peripheral verticalnondegenerative medial meniscus tearstreated with trephination alone at the timeof anterior cruciate ligamentreconstruction. Arthroscopy 2015;31:2411-2416.

22. Shelbourne KD, Carr DR: Meniscal repaircompared with meniscectomy for bucket-handle medial meniscal tears in anteriorcruciate ligament-reconstructed knees.Am J Sports Med 2003;31:718-723.

23. Shelbourne KD, Dersam MD: Comparisonof partial meniscectomy versus meniscusrepair for bucket-handle lateral meniscustears in anterior cruciate ligamentreconstructed knees. Arthroscopy 2004;20:581-585.

24. Rothermich MA, Cohen JA, Wright R:Stable meniscal tears left in situ at the timeof arthroscopic anterior cruciate ligamentreconstruction: A systematic review. J KneeSurg 2016;29:228-234.

25. Chahla J, Dean CS, Moatshe G, et al:Meniscal ramp lesions: Anatomy,incidence, diagnosis, and treatment.Orthop J Sports Med 2016;4:2325967116657815.

26. Sonnery-Cottet B, Conteduca J, ThaunatM, Gunepin FX, Seil R: Hidden lesions ofthe posterior horn of the medial meniscus:A systematic arthroscopic exploration ofthe concealed portion of the knee. Am JSports Med 2014;42:921-926.

27. Liu X, Feng H, Zhang H, Hong L, WangXS, Zhang J: Arthroscopic prevalence oframp lesion in 868 patients with anteriorcruciate ligament injury. Am J Sports Med2011;39:832-837.

28. Bhatia S, LaPrade CM, Ellman MB,LaPrade RF: Meniscal root tears:Significance, diagnosis, and treatment. Am JSports Med 2014;42:3016-3030.

29. Liu X, Zhang H, Feng H, Hong L, WangXS, Song GY: Is it necessary to repair stableramp lesions of the medial meniscus duringanterior cruciate ligament reconstruction?Am J Sports Med 2017;45:1004-1011.

30. Duchman KR, Westermann RW, SpindlerKP, et al: The fate of meniscus tears leftin situ at the time of anterior cruciateligament reconstruction: A 6-year follow-up study from the MOON cohort. Am JSports Med 2015;43:2688-2695.

31. Westermann RW, Duchman KR,Amendola A, Glass N, Wolf BR: All-insideversus inside-out meniscal repair withconcurrent anterior cruciate ligamentreconstruction: A meta-regression analysis.Am J Sports Med 2017;45:719-724.

32. LaPrade CM, Dornan GJ, Granan LP,LaPrade RF, Engebretsen L: Outcomes afteranterior cruciate ligament reconstructionusing the Norwegian Knee Ligament Registryof 4691 patients: How does meniscal repair orresection affect short-term outcomes? Am JSports Med 2015;43:1591-1597.

33. Shelbourne KD, Roberson TA, Gray T:Long-term evaluation of posterior lateralmeniscus root tears left in situ at the time of

anterior cruciate ligament reconstruction.Am J Sports Med 2011;39:1439-1443.

34. Parkinson B, Robb C, Thomas M,Thompson P, Spalding T: Factors thatpredict failure in anatomic single-bundleanterior cruciate ligament reconstruction.Am J Sports Med 2017;45:1529-1536.

35. Shelbourne KD, Jari S, Gray T: Outcome ofuntreated traumatic articular cartilagedefects of the knee: a natural history study.J Bone Joint Surg Am 2003;85-A(suppl 2):8-16.

36. Lattermann C, Jacobs CA, Reinke EK, et al:Are bone bruise characteristics andarticular cartilage pathology associatedwith inferior outcomes 2 and 6 years afteranterior cruciate ligament reconstruction?Cartilage 2017;8:139-145.

37. Røtterud JH, Sivertsen EA, Forssblad M,Engebretsen L, Årøen A: Effect on patient-reported outcomes of debridement ormicrofracture of concomitant full-thicknesscartilage lesions in anterior cruciateligament-reconstructed knees: Anationwide cohort study from Norway andSweden of 357 patients with 2-year follow-up. Am J Sports Med 2016;44:337-344.

38. Dunn WR, Wolf BR, Harrell FE Jr, et al.Baseline predictors of health-related qualityof life after anterior cruciate ligamentreconstruction: A longitudinal analysis of amulticenter cohort at two and six years. JBone Joint Surg Am 2015;97:551-557.

39. Gudas R, Gudait _e A, Mickevi�cius T, et al:Comparison of osteochondral autologoustransplantation, microfracture, ordebridement techniques in articularcartilage lesions associated with anteriorcruciate ligament injury: A prospectivestudy with a 3-year follow-up. Arthroscopy2013;29:89-97.




Documents

Review Article Meniscal and Chondral Pathology Associated ... · meniscal tears in acute injuries, but with advancing chronicity, medial meniscal tear rates increase while lateral