Accuracy Of MRI In Comparison With Arthroscopic In Anterior Cruciate Ligament And Meniscal Injuries Of The Knee

BackgroundThe knee joint is the largest joint in the body, consisting of4bones andan extensive network of ligaments and muscles and is very complicated.The femur and tibia are connected by four strong ligaments. Theseligaments assist to stabilize and control the motion of the knee joint. Thebones are cushioned by a gelatinous cartilage named meniscus that liesbetween them. All of these structures are at risk for damage. It is a pivotalhinge joint and permits flexion and extension as well as a slight medialand lateral rotation. This joint supports almost the whole weight of thebody and it is susceptible to hurts. The knee is the most frequently injuredjoint in all age groups. It is mainly vulnerable to damage during athleticactivities and exercise in young as well as older age group. The correctand timely diagnosis of the intra-articular knee lesions is important toproper management and better outcome. The intra-articular knee injury isnot sometimes easy to identify. The meniscus is a very significantstructure of knee joint. It functions for load transmission, shockabsorption, and stress reduction. The menisci are C-shaped structures that lie between the femur and tibia. Clinical manifestations of meniscal tearare mainly pain and frailty as a result of progressive instability andassociated ligament injury. They upturn the stability, facilitate lubricationand load bearing of the knee. The knee is become stable by a pair ofcruciate ligaments. Anterior and posterior cruciate ligaments rise from theanterior and posterior portions of the inter-condylar area of the tibia andare named by their tibial origin. The ACL is very important because itprevents the tibia from being pushed too far anterior relative to the femur.It is often torn during twisting or bending of the knee. The anteriorcruciate ligament resists hyperextension of the knee joint and theposterior cruciate resists hyperflexion. The normal ACL is located in theinter-condylar notch and it is a cruciate ligament which is one of the fourmajor ligaments of the human knee. The ACL initiates from deep withinthe notch of the distal femur. Its proximal fibers fan out along the medialwall of the lateral femoral condyle. There are two bundles of the ACL—the anteromedial and the posterolateral, called according to where thebundles attachment into the tibial plateau. The anterior cruciate ligamentattaches in front of the intercondyloid prominence of the tibia, beingblended with the anterior horn of the medial meniscus. These connectionslet it to resist anterior translation and medial rotation of the tibia, inrelative to the femur. It has low-signal structure on T1WIs; it often displays some linear striations near its insertion onto the medial tibialspine when seen on sagittal images.The aim of this study was to detect the accuracy of routine magneticresonance imaging (MRI) done and its agreement with arthroscopy inmeniscal and anterior cruciate ligament injuries of the knee. MRIscanning of the knee is a commonly used, non-invasive investigation todetermine the meniscal tears and ligamentous injuries. Knee joint injuryis common in young people as well as old age group. Injury results invarious intra-articular knee lesions and the early diagnosis is veryimportant. Even with the investigations, the diagnosis remainsinconclusive some times. If MRI diagnosis has as accurate as arthroscopy,this expensive and invasive investigation could be avoid. Unfortunately,arthroscopies are invasive and require a skilled surgeon.ObjectiveThe purpose of the study was to compare MRI accuracy witharthroscopy in menisci tears and anterior cruciate ligament injuries of theknee joint. Sensitivity, specificity, accuracy, positive and negativepredictive values, P value and kappa agreement measures were calculated. Patients and MethodsPatientsThis study was done to identify the precision of routine magneticresonance imaging (MRI) and its arrangement with arthroscopy inmeniscal and anterior cruciate ligament lesions of the knee. The studywas performed from January2011till December2012at China JapanUnion Hospital (Third Clinical Hospital) of Jilin University.We studied71patients. Those who were selected for the study varied inage between3to68years of age (39men and32women) and whom hadknee lesion and went through arthroscopy after MRI assessment in ourhospital in the years2011and2012. These patients were reported to havepain, popping, locking, shakiness and inflammation. Once history takingand clinical examinations were done, these patients were referred to ourdepartment for magnetic resonance imaging (MRI) evaluation beforearthroscopy. With each single patient’s medical history, containinginformation of both past and present illnesses, radiological examinations,treatments, and their outcomes; being electronically recorded in thehospital computer system, retrospective data was easily made availableby the system and thus retrospective analysis was made possible.Selected conditions of cases:I. Patients with past of injury with the clinical symptoms and/or pastindicative of knee intra-articular injury.II. Patients who had went through arthroscopy after MRI evaluation. III. No age restriction (young and old included) and no sex preference(male and female included).Excluded conditions:I. Patients with prior meniscus surgeryII. Knee ligament fixing or restorationsIII. Prior knee arthroscopiesIV. Patients with present joint disease e.g. rheumatoid arthritisMethodsMRI-ExaminationThere are several combinations of sequences that can beperformed in routine MRI of the knee. Even though there isn’t thegreatest combination. Routine MRI of the knee is done in the axial,sagittal, and coronal planes. Some form of T2weighting must beperformed in each of the three planes. Most authors suggest Tl-weightedsequences in the sagittal plane and optionally in the coronal plane.T2weighted pulse series scan cover proton-density-weighted images asdouble-echo sequences. The accessibility of fast spin-echo (FSE)sequences has greatly enhanced the time efficiency of knee MRI. InT2weighing with fat suppression, FSE sequences are sensitive tobone marrow edema and cartilage lesions and fluid collections ingeneral. The slice thickness of a routine scanning protocol must not bemore than4mm in all planes. All patients underwent MRI examination before going througharthroscopy. The examinations were executed on a GE SignaHDx1.5Tesla (T) MRI, using Coil Mode HD TR knee PA. The patient lied downhorizontally with the feet entering first. The subsequent sequences wereexecuted:a) Sagittal fat suppression proton densityTR:2340, TE: min full with min16.8and max111.8; Slicethickness:4.0mm with Spacing:1mm; field of view:17.0; echo trainlength:10; band width:20.83; pulse sequences: FSE-XL; and foracquisition timing: frequency:288with direction A/P,Phase192; NEX:2.00; and shim: autob) Sagittal fat suppression T2TR:4520, TE:85.0; Slice thickness:4.0mm with Spacing:1mm;field of view:18.0; echo train length:19; band width:31.25; pulsesequences: FRFSE-XL; and for acquisition timing: frequency:288withdirection A/P, phase224; NEX:2.00; and shim: autoc) Sagittal T1TR:820, TE: min full with min18.6and max37.2; Slice thickness:4.0mm with Spacing:1mm; field of view:18.0; echo train length:3;band width:20.83; pulse sequences: FSE-XL; and for acquisition timing:frequency:384with direction A/P, phase256; NEX:2.00; and shim: autod) Coronal fat suppression proton density TR:2800, TE:25; Slice thickness:4.0mm with Spacing:1mm;field of view:18.0; echo train length:14; band width:20.83; pulsesequences: FSE-XL; and for acquisition timing: frequency:288withdirection A/P, phase224; NEX:2.00; and shim: autoe) Coronal T1fat suppression echoTR:720, TE: min full with min16.1and max32.3; Slice thickness:4.0mm with Spacing:1mm; field of view:18.0; echo train length:3.0;band width:20.83; pulse sequences: FSE-XL; and for acquisition timing:frequency:320with direction R/L, phase224; NEX:2.00; and shim: autoThe magnetic resonance imaging (MRI) interpretation wasconsidered by numerous Masters and PhD radiology students, however,the final corrected conclusion was affirmed by professional radiologists.In the event that there would be conflict on realizing a conclusion, suchcases were deliberated in the morning conferences the day after whereseveral highly trained and professional radiologists would confer amongstand come to an agreed conclusion. Their interpretations were based onthe patient’s medical history with a particular emphasis on suspecteddiagnosis or radiographs of the knee.The state of the menisci and cruciate ligaments was recorded. Ameniscal tear was stated to exist if an elevated intensity signal waspresent in the meniscus and this stretched outwardly on contiguous slicesor if the general contour of the meniscus was interrupted. A diagnosis of cruciate ligament lesion necessitate a minimum of one of the followingfindings: the ligament was in an anomalous position, unidentifiable, itwas disjointed or a presence of an atypically high intensity signal in theway of the cruciate ligament.ArthroscopyArthroscopy was done by the arthroscopy surgeons from theorthopedics department of our hospital, using the standard method withthe understanding of the result of the MRI examination. MRI andarthroscopy findings were associated only once the study was completed.Statistical analysisStructures involved in the study were medial and lateral menisci andanterior and posterior cruciate ligaments. Meniscal tear and degenerationwere deliberated as one group matched against the normal menisci.Ligaments tear, regardless of partial or complete, were collected underthe group ligament tear.Data were coded and analyzed via the Statistical Package for theSocial Sciences (SPSS) version16. P values <0.05were considered asstatistically significant. Accuracy, sensitivity, specificity, positivepredictive value, negative predictive value, p value and kappa agreementmeasures were calculated to test the legitimacy of MRI compared againstarthroscopy. Sensitivity, specificity, positive predictive value, negative predictivevalue and accuracy of MRI to analyze meniscal and cruciate ligamentinjury and of arthroscopy to diagnose the same injuries were completedby using the4by4Statistical Table. Arthroscopy is the gold standard fordiagnosis of meniscal tears and cruciate ligamentous injuries, which issupported by our results.RESULTSThe study comprised of71patients age ranging from3to68years old(39men and32women). Each and every one of these patients had gonethrough MRI and then went through arthroscopy. Evaluation of MRIdiagnosis was completed by comparing with the arthroscopy diagnosis,which is considered the gold standard.We obtained11true positives,5false positives,7false negatives and48true negatives for the medial meniscus ligament injuries. The overallvalues for the MRI diagnosis of the medial meniscus was83.0%,68.8%,87.3%,61.1%,91.6%for accuracy, positive predictive value, negativepredictive value, sensitivity, and specificity, respectively, and significantKappa agreement0.53.We found15true positives,7false positives,1false negative and48truenegatives for the lateral meniscus ligament injuries. The overall values forthe lateral meniscus was88.7%,68.2%,98%,93.8%,87.3%for accuracy, positive predictive value, negative predictive value, sensitivity, andspecificity, respectively, and a considerable Kappa agreement0.71.We obtained24true positives,1false positive,5false negatives and41true negatives for the anterior cruciate ligament tears. And overall valuesfor the diagnosis of the magnetic resonance imaging of the anteriorcruciate ligament tear combined were91.5%,96.6%,89.1%,82.8%,97.6%for accuracy, positive predictive value, negative predictive value,sensitivity, and specificity, respectively, and an excellent Kappaagreement0.71.ConclusionThe conclusion was that MRI is a dependable and useful diagnostic toolfor displaced meniscal and anterior cruciate ligament tears. PreoperativeMRI can assist orthopedic surgeons in choosing proper therapy for theirpatients. MRI in clinically doubted patients of meniscal injuries woulddecrease the number of needless diagnostic arthroscopies.We recommend MRI as the primary diagnostic tool for internal kneelesions; however, arthroscopy should be done in cases where MRIfindings do not agree with findings of the patients or in cases clinicallydiagnosed as complete ACL tears where reconstruction surgery isindicated.