Presentation on theme: "Meniscal Tears and Their Treatment"— Presentation transcript:
1Meniscal Tears and Their Treatment Robert S. Fawcett M.D., M.S.York Hospital Family Medicine ResidencyYork, PA
2ObjectivesDiscuss important points in history, physical and testing that lead to a diagnosis of damaged meniscusUnderstand the short and long term outcomes of meniscectomyDiscuss the benefits and implications of surgical vs. conservative management of meniscal tear
3EpidemiologyOverall incidence unknown, but surgical incidence is per 100,000 per yearMost common orthopedic surgical procedure1/3 of meniscal tears are sports-related (most of the rest from MVAs)1/3 of meniscal tears associated with ACL injury
4The medial meniscus is somewhat semicircular in appearance The medial meniscus is somewhat semicircular in appearance. It is approximately 3.5 cm in length in the anteroposterior dimension and considerably wider posteriorly than it is anteriorly. Its radius of curvature varies, giving it greater length in the sagittal plane than in the coronal plane. The anterior horn is attached to the tibial plateau in the area of the anterior intercondylar fossa, 6 to 7 mm in front of the ACL insertion. An intermeniscal, or “transverse,” ligament is present in 64% of individuals; this connects the anterior horn (posterior fibers) of the medial meniscus and the anterior horn (anterior fibers) of the lateral meniscus. The posterior horn attaches to the posterior intercondylar fossa between the attachments of the lateral meniscus and the posterior cruciate ligament (PCL). The medial meniscus is continuously attached to the joint capsule along the entire periphery. The coronary ligament represents the tibial portion of this capsular attachment. At its midpoint, the medial meniscus is firmly attached to the femur and tibia through a robust thickening in the capsule known as the deep medial collateral ligament.Lateral MeniscusThe lateral meniscus covers a larger portion of the tibial surface than does the medial meniscus. Its radius of curvature remains fairly constant, giving the lateral meniscus an almost circular appearance. The anterior horn is attached anterior to the intercondylar eminence, just posterior and lateral to the ACL attachment with which it partially blends. The posterior horn attaches posterior to the intercondylar eminence, just in front of the posterior end of the medial meniscus. In 50% of individuals, anterior fibers of the posterior enthesis extend to the lateral aspect of the medial femoral condyle, forming the anterior meniscofemoral ligament (ligament of Humphry). In 76% of cases, the posterior fibers of the posterior horn cross posterior to the PCL and attach to the intercondylar fossa of the medial femoral condyle, forming the posterior meniscofemoral ligament (ligament of Wrisberg). The lateral meniscus has only a loose peripheral attachment to the capsule, which is interrupted by the popliteus tendon. Lateral meniscal variants, including the most recognized discoid meniscus, have a reported prevalence as high as 16.6% (see “Special Considerations”).--DeLee and DeLee
5Structure of the Meniscus Medial is semicircularMoves 2-5 mm through full ROMLack of motion may promote tearsFibers from the deep medial collateralLateral almost a complete circleMoves ~1 cm through full ROMBoth made of fibrocartilage75% circumferential type 1 collagen fibers25% radial fibersBlood supply thru plexus from superior and inferior geniculate arteries.Anterior horn of med meniscus attaches ant to fibers of ACLPosterior horn is wider and attaches just posterior to fibers of ACLLaterally, mm is anchored to medial collateral fibers.64% of people have transverse lig connecting med and lat menisci anteriorlyMed meniscus attached to joint capsule throughout its circumference, tightly at med collateral.Ant and post horns of semicircular lat meniscus attach lat to lat fibers of ACL.Lat men more loosely attached than medial.Ligaments of Humphreys and Wrisberg attach from posterior portion of lat men, run adjacent to post CL, and attach to fem cond.
7Structure of the Menisci Vascular supply good in the most peripheral 20% of the fibersSupplied by the geniculate arteriesInner 1/3 of the ring is avascularRelatively thinNourished through synovial fluidMiddle 1/3 of the ring is combination
8Function of the Menisci Distribute load across the knee joint2-4x body weight during walking6-8x body weight during runningAxial compression is converted to “hoop stress”, or circumferential elongation in the meniscusLateral meniscus distributes more load than medial meniscus, which contributes to greater degeneration if disruptedMenisci deepen the socket of the tibial plateau, contributing to stability of knee
9Function of the Menisci Wedge shape limits translation of femur on tibial plateauMenisci forced posteriorly in flexion, anteriorly in extension of the kneeMenisci reduce stresses on the ACLMenisci force synovial fluid into articular cartilage (helping to nourish the white zone) during compression.
10PathophysiologyIn acute knee injuries with ACL intact, medial meniscal injury is 5 times more likely than lateralIn acute knee injuries with ACL ruptured, lateral meniscus more likely to be involvedIf ACL is previously disrupted, lateral meniscal injury is more likely than medialIn repetitive deep squatting, medial meniscus most likely to be injured (20:1)Medial meniscus is tethered to joint capsule and is less stableLat more likely than medial with ACL due to shift of lateral femoral condyle
11History: the Key to Diagnosis Twisting on planted footInertial forces or external forcesAcute effusion in acute injuryWaxing and waning course with pain and effusion intermittently in chronic injuryThe older the patient, the less likely that history will be revealingMore likely to occur with trivial traumaDifficult to distinguish from DJD
12}80% }95% Physical Exam * Finding/Test Sensitivity Specificity Joint Line Tenderness71%27%McMurray58.5%93.4%Apley58%80%Thessaly 5oThessaly 20o66%Me, 81%La89%Me, 92%La96%Me, 91%La97%Me, 96%LaMRI75-87%87-93%}80%}95%*Clinical examination is the primary diagnostic tool for intra-articular and meniscal injuries. The most common findings, similar to those of adults, are joint-line tenderness and effusion   . Because of the diversity of pathology and the difficulty of examination in children in an acute setting, the diagnostic accuracy of clinical exam for meniscus tear has been shown to be as low as 29% to 59% in series with multiple examiners   . In children, anteromedial or anterolateral joint-line pain may be caused by patellofemoral pain, patellar instability, iliotibial band friction, osteochondritis dissecans, or other lesions. Sensitivity of McMurray and Apley tests is estimated to be 58% with even lower specificity  . Two recent studies, by examiners with significant pediatric sports medicine experience, showed the diagnostic accuracy of clinical exams to be 86.3% and 93.5% overall   . When medial meniscus tears were looked at alone, sensitivity and specificity of clinical exams were 62.1% and 80.7%, respectively  . Sensitivity and specificity for lateral meniscal tears were 50% and 89.2%, respectively  .Comparison of knee magnetic resonance imaging findings in patients referred by orthopaedic surgeons versus nonorthopaedic practitioners . Arthroscopy: The Journal of Arthroscopic & Related Surgery , Volume 18 , Issue 2 , PagesP . Sherman , B . Penrod , M . Lane , J . WardAbstractPurpose: To compare the percentages of normal magnetic resonance imaging (MRI) examination results and clinically significant knee abnormalities in patients referred for MRI of the knee by orthopaedic surgery residents and staff with those of patients referred by nonorthopaedic practitioners. Type of Study: Retrospective review of MRI findings. Methods: MRI reports of 754 patients (454 men and 300 women) were retrospectively reviewed; 373 patients were referred from the Department of Orthopaedic Surgery and 381 patients were referred from nonorthopaedic practitioners. The number of normal examination results, meniscal and ligament tears, chondral abnormalities, and Baker’s cysts was tabulated and analyzed using a χ-square injury analysis. Results: The rate of normal results for nonorthopaedic practitioners was 33.9% (129 of 381) compared with 15.3% (57 of 373) for orthopaedic surgeons (P < .001). Nonorthopaedic surgeons referred 69.4% (129 of 186) of the patients who had normal examination results. The positive finding for a lateral meniscus tear was 29.2% (109 of 373) for orthopaedic surgeons compared with 19.1% (73 of 381) for nonorthopaedic practitioners, which was statistically significant (P = .002) in regard to the distribution of injuries. No difference was found in other abnormalities assessed. Conclusions: Patients referred by nonorthopaedic practitioners had significantly more normal knee MRI examination results than did those referred by orthopaedic surgeons.*This test has not yet undergone external validation studies
13Thessaly Test? Done with pt standing, first on normal leg Flex knee 5 degrees, rotate body on fixed leg back and forth 3 times, holding examiner’s hands for stabilityFlex further to 20 degrees and repeatRepeat on affected legPositive is pain at joint line or feeling of locking or catching
14Value of MRI as Diagnostic Tool Studies do NOT prove it superior to composite clinical examMany false positives appearMRI has high NEGATIVE predictive valueSensitivity and specificity keep getting better as technology improvesHow will MRI result change treatment?No surgeon would touch a knee without oneHelps with planning procedureTears are seen as high-grade signal areas within the substance of the meniscus. Radiologists user grading system to delineate these signal changes, with grade 0 being normal meniscus, grade 1 and 2 high signal intrameniscal areas that do not abut the free meniscal edge, and grade 3 high signal area that tracks to the edge of the meniscus. Grade 3 changes are the only changes consistent with clinically significant meniscal tear and, for this reason, care must be used when interpreting MRI images and reports. Care must also be used when interpreting signal changes in a patient who has had previous meniscal surgery, as MRIis often unreliable in these cases.
17Treatment Options Total meniscectomy Partial meniscectomy Meniscal repairInside outOutside inAll insideConservative (No operative intervention)
18Consequences of Meniscectomy As early as 1948 Fairbanks noted increased osteophyte formation and femoral cartilage deterioration in meniscectomized kneesTotal meniscectomy remained a common procedure until the 1980’sIn medial meniscectomy, load bearing surfaces are halved, doubling stress on tibial plateauIf 15-30% of meniscus is removed, forces between tibia and femur increase up to 350%It is now appreciated that menisci serve many functions, including increasing contact area and congruency of the femoral-tibial articulation. The menisci load-share and reduce contact stresses across the joint. It is estimated that menisci transmit up to 50% to 70% of the load in extension and 85% in 90° of flexion  . Baratz and Fu showed that, following total menisectomy, the contact area decreased by 75% and contact stresses increased 235%  . They also documented deleterious effects of partial menisectomy, demonstrating that contact stresses increased in proportion to the amount of meniscus removed. Excision of narrow bucket-handle tears of the medial meniscus increased contact stress by 65%, and 75% resection of the posterior horn increased contact stresses equivalently to that of total menisectomy  . Repair of meniscal tears reduced contact stresses to normal. Other studies corroborate the mechanical importance of the meniscus [
19Meniscus Repair Used in longitudinal tears Many fixation devises, none better than sutures, though some are fasterOutside in, inside out, and all inside techniqueInside out most useful in posterior or lateral tears.Outside in most useful for anterior tears.All inside techniques involve specialized darts or anchors or arrows with methods of insertion and are not as secure
20Criteria for Meniscal Repair vs. Partial Meniscectomy CriterionRepairPtl. MeniscectomyDistance from rim<3mm>3mmMobility of fragmentStableMobileAge of injuryRecentOldRet. To PlayLaterSoonerAge of patientYoungerOlderSome small, nondisplaced meniscal tears in the outer vascular region may heal spontaneously or become asymptomatic    . Nonoperative treatment consists of rehabilitation of the injured knee with the avoidance of pivoting and sports for 12 weeks.The majority of meniscal tears in pediatric patients are large and require surgical treatment    . Arthroscopic management is standard with partial menisectomy (Fig. 2) or meniscal repair using outside-in, all inside (Fig. 3) , or inside-out techniques (Fig. 4)    . We believe that, in children and adolescents, meniscal repair should be attempted, instead of partial menisectomy, for middle third and outer third meniscal tears because of the theoretical greater healing potential at this age. Long life span and poor results of total and near-total menisectomy, and lack of longer-term results of partial menisectomy, encourage meniscal salvage attempts. Inside-out techniques are useful for anterior horn medial or lateral meniscal tears (Fig. 4) . Meniscal-body and posterior-horn tears are repaired b the traditional inside-out repair with vertical or horizontal sutures. Zone-specific cannulas can direct the flexible suture needles to appropriate positions to avoid neurovascular structures. We routinely make an incision posteromedially or posterolaterally to identify and retrieve the suture needles and tie the sutures at the joint capsule, protecting the saphenous nerve and vein medially and the peroneal nerve laterally. Newer all-inside devices have facilitated meniscal repair in adults (Fig. 3) . Reports of articular cartilage damage from heads of bioabsorbable arrows and darts exist   and many of the devices extend too far through the capsule in a pediatric knee, with potential for pain and neurovascular injury. We prefer more recent all-inside low-profile suture devices for posterior horn tears in adolescent knees. For smaller tears without substantial displacement, we use these devices alone. For larger tears with displacement, eg, bucket-handle tears, we use them in a hybrid manner with inside-out sutures (Fig. 5) . Regardless of instrumentation used, surgical principles are important to maximize meniscal healing and include preparation of the repair site using abrasion or trephination, anatomic reduction of the meniscal tear, adequate strength and durability of repair devices, and protected knee mobilization.
21Meniscus Repair--Recovery Pts must wear brace with pwb for 2 weeksSedentary workers back to work in 1 weekLaborers back in 6-8 weeksAthletes back in weeks76% “excellent” results after 10 years**
22Partial Meniscectomy Done when tear involves interior 70% May be done when athlete wants to resume activity ASAPDone with mobile fragments10-35 minute arthroscopic procedure under regional or general anestheticMobile areas removedEdges contoured to “prevent further tears”Immediate partial weight bearing allowedCrutches for 1-2 days
23Partial Meniscectomy--Recovery Sedentary workers back to work in 1 weekLaborers back in 2-4 weeksAthletes back in 2-6 weeks88% “excellent” results at 15 years**Burks RT, Metcalf MW, Metcalf RW; 15 yr f/u of arthroscopic partial meniscectomy; Arthroscopy 1997; 13:673-9.
24Conservative TherapyNot an option if knee locked, fragment not reducedSymptom relief with post-exercise RICESymptom relief with NSAIDS, immobilizationPhysical therapy focusing on closed chain exercise of quadriceps and hamstringsFailure includes recurrent effusion, recurrent locking or pain that interferes with ADLsNo randomized trials
25Conservative Study Result Retrospective review of 3612 arthroscopiesIdentified 80 “stable” tears (<3mm movement) for whom nothing was done70 were longitudinal, 10 were radialOnly 6 needed subsequent surgery, 4 of which had had additional trauma32 patients had “second look” surgery17/22 longit. tears, 0/6 radial tears healed completelyWeiss CB, Lundberg M, DeHaven KD, Gillquist J; Non-operative treatment of meniscal tears. JBJS A(6):
26Conservative Study Results “Stable” tears at ACL reconstruction left to heal and 2nd look removing ACL hardwareLateral: 74% healed, 6% incompletely healed, 14% unhealedMedial: 56% healed, 6% incompletely healed, 24% unhealedHealing rate was “length dependent”Yagashita et al. Am J Spts Med (8):1953
27Conservative Study Results 32 patients30 lateral and 10 medial meniscal tears along with 25 ACL tears and 7 PCL tearsArthroscoped initially with repeat at 3 mo.Lateral meniscus: 69% completely healed and 18% incompletely healedMedial meniscus: 58% completely healed and 0% incompletely healedIhara H, Miwa M, Takayanagi K, Nakayama A. Clin Orthop Relat Res Oct;(307):
28Ihara: Results Without Surgery InjuryResults at 2nd LookLat Meniscus69% healed completely,18% healed partiallyMedial Meniscus58% healed completely0% healed partiallyAnt. Cruc.Ligment80% healed “satisfactorily”Post Cruc.Ligament3/7 (40%) healed “satisfactorily”
29Cochrane Review 2002 No evidence for comparing surgery to no treatment Partial is better than total meniscectomy:Less operative timeEnhanced recovery rateImproved long term stabilityArthroscopic is better than open meniscectomyQuicker recovery post-opNo long term advantages have been shownA Cochrane library review evaluated "the effects of common surgical interventions in the treatment of meniscal injuries of the knee. The four comparisons under test were: a) surgery versus conservative treatment, b) partial versus total meniscectomy, c) excision versus repair of meniscal tears, d) surgical access, in particular arthroscopic versus open.Three trials, involving 260 patients, which addressed two (partial versus total meniscectomy; surgical access) comparisons were included. Partial meniscectomy may allow a slightly enhanced recovery rate as well as a potentially improved overall functional outcome including better knee stability in the long term. It is probably associated with a shorter operating time with no apparent difference in early complications or re-operation between partial and total meniscectomy. The long-term advantage of partial meniscectomy indicated by the absence of symptoms (symptoms or further operation at six years or over: 14/98 versus 22/94; Peto odds ratio 0.55, 95% confidence interval 0.27 to 1.14) or radiographical outcome was not established. The results available from the only trial comparing arthroscopic with open meniscectomy were very limited in terms of patient numbers and length of follow-up. However it is likely that partial meniscectomy via arthroscopy is associated with shorter operating times and a quicker recovery.Reviewers' conclusions: The lack of randomised trials means that no conclusions can be drawn on the issue of surgical versus non-surgical treatment of meniscal injuries, nor meniscal tear repair versus excision. In randomised trials so far reported, there is no evidence of difference in radiological or long term clinical outcomes between arthroscopic and open meniscal surgery, or between total and partial meniscectomy. Partial meniscectomy seems preferable to the total removal of the meniscus in terms of recovery and overall functional outcome in the short term." (1)
30Summary: What We KnowThe meniscus, torn or intact, helps to stabilize and dissipate axial force in the kneeDegenerative changes develop more frequently in meniscectomized (total or partial) than in normal knees (Williams, others)When meniscal repairs fail, pts are often engaging in the same activity as initial injuryLongitudinal tears heal more readily than radial tears and simple or bucket handle tears heal more readily than complex ones
31Summary: What We KnowPeripheral tears (in the vascularized area) heal more readily than central tears (Noyes, Krych)Meniscal tears are accompanied by ligament tears in many casesRepairing both meniscus and ligaments (when both injured) improves outcomes (Noyes)Ligamentous pathology with meniscal tears makes degenerative changes more likely
32What We KnowYounger pts do better with meniscal repair than older patients (Mintzer)Less surgery is better than more surgeryArthroscopy better than openPartial better than complete meniscectomy (Cochrane)
33What We Don’t Know Whether no surgery is better than less surgery Whether operating on stable radial tears improves outcomesHow to tell without surgery that conservative treatment is a reasonable optionWhether and how long to immobilize the acute tearIf a repair is undertaken, what timing and type of repair has the best outcomesIf no repair is done, whether and when to do a “second look”
34BibliographyKarachalios T, Hantes M, Zibis AH, et al. Diagnostic accuracy of a new clinical test (the Thessaly test) for early detection of meniscal tears. J Bone Joint Surg 2005;87:955–62.Krych AJ, McIntosh AL, Voll, Michael AE, Stuart J, Dahm DL. Arthroscopic Repair of Isolated Meniscal Tears in Patients 18 Years and Younger. Am. J. Sports Med. 2008; 36; 1283 originally published online Mar 4, 2008.Manson TT, Cosgarea AJ. Meniscal injuries in active patients. Advanced Studies in Medicine November-December 2004, 4(10):Muellner T, Weinstabl R, Shabus R, Vecsei V, Kainberger F; The diagnosis of meniscal tears in athletes: a comparison of clinical and magnetic resonance imaging investigations. Am J Sports Med 1997; 25:7-12.Ihara H, Miwa M, Takayanagi K, Nakayama A. Clin Orthop Relat Res (307):Johnson MJ, et al. (1999). Isolated arthroscopic meniscal repair: A long-term outcome study (more than 10 years). American Journal of Sports Medicine, 27(4): 44–49.Mintzer CM, Richmond JC, Taylor J. Meniscal repair in the young athlete. Am J Sports Med 1998;26:630-3.Noyes FR, Barber-Westin SD. Arthroscopic repair of meniscal tears extending into the avascular zone in patients younger than twenty years of age. Am J Sports Med 2002;30:Weiss CB et al. Non-operative treatment of meniscal tears. JBJS A(6):Howell JR Handoll HHG. Surgical treatment for meniscal injuries of the knee in adults (Cochrane Review). In: The Cochrane Library, Issue 3, Oxford: Update Software.Williams RJ et.al. MRI evaluation of isolated arthroscopic partial meniscectomy patients at a minimum five year follow-up. HSSJ :35-43.