Bilateral bucket handle medial meniscal tears of the knee: A case report

INTRODUCTIONMeniscal tears may cause knee pain and functional impairment. Bilateral bucket-handle meniscal tears is an uncommon condition.PRESENTATION OF CASEThis report presents the case of a 35-year-old male patient with bilateral bucket handle medial meniscal tears that occurred nonsimultaneously. The lesions were treated arthroscopically with partial resection in one knee and meniscal suture in the other.DISCUSSIONBucket handle meniscal tear of meniscus without underlying meniscal, ligamentous pathology or lower limb deformity is a rare condition.CONCLUSIONTo our knowledge, bilateral bucket handle medial meniscal tears without underlying meniscal anomalies have been reported in only two cases before, and our case is the third one.     

Repair of meniscal tears with the absorbable Clearfix screw: results after 1–3 years

Introduction Total meniscus resection usually leads to osteoarthritis of the knee joint. Preservation and refixation of the injured menisci are therefore of great clinical importance.Materials and methods The present study examines 40 meniscal injuries in 37 patients that were arthroscopically treated with Clearfix meniscal screws (Mitek, Norderstedt, Germany) in the period from August 1999 to December 2002. The mean patient age was 27.7 (range 16–62) years. Nine patients were female. A total of 24 patients (27 meniscal tears) also had an anterior cruciate ligament (ACL) lesion, and 5 patients had cartilage injuries. Twenty-two patients were treated within the first 2 weeks following the trauma, 10 patients within 8 weeks, and 5 patients after 8 weeks. The lesions were a bucket-handle tear of the medial meniscus in 11 cases and a bucket-handle tear of the lateral meniscus in 2 cases. The posterior horn of the medial meniscus was torn in 13 cases, and the pars intermedia in 3 cases. The posterior horn of the lateral meniscus was torn in 8 cases, and the pars intermedia in 3 cases. The mean tear length was 2.9 (±1.5) cm and was fixed with an average of 1.8 (±0.7) screws. In 7 cases, the anterior horn was treated with an additional meniscal suture. A total of 35 patients were examined after an average of 18 (range 7–45) months.Results In the event of a moderate outcome, MRI was performed as part of the follow-up investigation. The average Lysholm score was 93 (±7.4), the Tegner activity index was 6.3 (±2.0) before the accident and 5.8 (±2.0) at the follow-up, the Marshall knee score was 47 (±3.8). The VAS pain assessment was 1.6 (±1.3) and the VAS function assessment was 7.9 (±1.6). Of the 7 patients with a moderate result, 2 patients without additional ligament lesions suffered re-ruptures after 6 and 13 months, respectively. The other 5 patients with a moderate result each had multiple accompanying injuries or pre-existing damage to the affected knee joint.Conclusion The Clearfix screws achieved a clinical success rate of 82% in isolated meniscal tears in stable knee joints and a clinical success rate of 100% with additional ACL reconstruction. In view of the good clinical results and the simple procedure for use, the implant should be recommended for meniscal refixation.     

Diagnostics of degenerative meniscal tears at 3-Tesla MRI compared to arthroscopy as reference standard

Introduction The goal of this study was to evaluate the diagnostic performance of 3-Tesla MRI for the assessment of degenerative meniscal tears in clinical practice. Materials and methods In patients with chronic knee pain, a negative history of acute trauma and a mean age of 52 years, 3-Tesla MRI were performed a few days prior to arthroscopy. In 86 menisci, diagnostic values of 3-Tesla MRI for the detection of degenerative tears were evaluated using arthroscopy as reference standard. The MRI classification, for meniscus diagnostics, described by Crues was used. Results At arthroscopy, all tears identified (19 horizontal, 7 complex, 3 radial) were degenerative as confirmed by histological examination. MRI grade II lesions had a prevalence of 24% and a rate of 24% of missed tears, whereas grade I lesions were not associated with a torn meniscus at arthroscopy. For meniscal tears, (grade III) sensitivity and specificity of 3-Telsa MRI was 79 and 95% for both menisci, 86 and 100% for the medial meniscus, and 57 and 92% for the lateral meniscus. The best diagnostic performance was found for complex tears, horizontal tears showed relatively good results, poor results were documented for radial tears. Conclusion For the medial meniscus, where horizontal and complex tears were more prevalent, 3-Tesla MRI shows a higher accuracy than for the lateral meniscus. Particularly with regard to the medial meniscus, 3-Tesla MRI could be effectively used when a degenerative tear is suspected. Nevertheless, in regard to a remarkable number of false positive and false negative findings the diagnostic value of a 3-Tesla MRI investigation should not be overestimated.     

膝关节内外侧半月板后根部撕裂的MRI诊断价值

目的:探讨MRI对膝关节内外侧半月板后根部撕裂的诊断价值。方法:回顾性分析2012年1月至2016年1月,关节镜下证实为半月板后根部撕裂的患者43例。其中男25例,女18例;年龄27~69(42.5±8.3)岁;右侧27例,左侧16例。由2名医师采用双盲法独立回顾性分析经关节镜证实的43例半月板后根部撕裂患者的MRI表现,计算MRI对半月板后根部撕裂的诊断敏感性、特异性和准确性,并计算膝关节韧带损伤及半月板脱位等伴随情况。结果:143例中,关节镜手术证实43例半月板后根部撕裂,包括内侧撕裂24例,外侧撕裂19例。医师A诊断内侧半月板后根部撕裂的敏感性、特异性、准确性分别为91.67%、86.6%、83.9%,伴内侧半月板突出19例,伴前交叉韧带撕裂2例;外侧半月板后跟部撕裂的敏感性、特异性、准确性分别为73.7%、79.9%、79%,伴外侧半月板突出4例,伴前交叉韧带撕裂16例。医师B诊断内侧半月板后根部撕裂的敏感性、特异性、准确性分别为87.5%、87.4%、87.4%,伴内侧半月板突出19例,伴前交叉韧带撕裂2例;外侧半月板后跟部撕裂的敏感性、特异性、准确性分别为78.9%、82.3%、82.5%,伴外侧半月板突出4例,伴前交叉韧带撕裂16例。2名医师采用MRI诊断内、外侧半月板后根部撕裂的一致性均好,Kappa值分别为0.81和0.67。结论 :膝关节MRI诊断内外侧半月板后跟部撕裂及其伴随征象具有较大价值,为临床医生术前诊断提供依据,值得临床推广应用。     

Hi-frequency electrical cautery stimulation in the treatment of displaced meniscal tears

This is a preliminary report of four cases of meniscal displaced tears: two bucket handle medial meniscus tears, one complex tear in the avascular zone or lateral meniscus, and one longitudinal full-thickness tear on the lateral meniscus. These tears were treated by applying hi- frequency current stimulation to the tissues and obtaining total meniscal visual healing on a second arthroscopic view after 6 weeks.Arthroscopy 1998 Sep;14(6):566-71     

Arthroscopic management of degenerative meniscus tears in patients with degenerative arthritis

Frequently, meniscal pathology accompanies degenerative changes affecting the articular surface of the knee. The attritional changes in the meniscus lead to fragmentation of the meniscus and a variety of tears, usually of the posterior horn of the medial meniscus. A prospective study of the results of arthroscopic partial meniscectomy in the presence of at least Outerbridge Grade III chondromalacia of the accompanying joint surface was performed between 1980 and 1984. Eighty-seven knees in 84 patients were studied. The mean age was 62 (29-84) years. The right knee was involved in 44 patients, and 47 were men. Preoperative radiographs demonstrated osteoarthritis in 53 patients. The medial meniscus was involved in 82, while the lateral meniscus was affected in nine knees. Four knees had involvement of both menisci. In 72 knees, the most frequent lesion was a tear of the posterior horn of the medial meniscus. The most frequent configuration of the tears was a flap in 42. The morbidity was small with the use of ambulatory aids being 10 +/- 13 (mean +/- SD) days. Subsequent surgery was performed on six knees consisting of two total knee arthroplasties, two upper-tibial osteotomies, one repeat arthroscopic meniscectomy, and one popliteal cyst excision. Two patients had poor results related to progression of their arthritis and one developed osteonecrosis. Five patients were unchanged from their preoperative status. Subchondral sclerosis or osteophytes on the preoperative radiographs correlated with 72% compared to 90% satisfactory results in the absence of these findings (p less than 0.03). Complications consisted of superficial thrombophlebitis in three, hemarthrosis in one, and superficial infection in one patient.(ABSTRACT TRUNCATED AT 250 WORDS)     

Meniscus tears accelerate joint space loss and lateral meniscal extrusion increases risk of knee arthroplasty in middle-aged adults

We sought to use publicly available data from the Osteoarthritis Initiative (OAI), a multicenter prospective cohort study, to determine the rate of joint space loss and likelihood of knee arthroplasty due to magnetic resonance imaging (MRI)-diagnosed meniscal tears or meniscal extrusion in middle-aged adults with no to mild knee osteoarthritis. Participants (n = 2199; mean age, 60.2 years) with Kellgren-Lawrence osteoarthritis grades 2 (mild) (48.7%) or 0 to 1 (none) (51.3%) underwent knee MRIs at enrollment and were followed radiographically for 8 years and for total knee arthroplasty (TKA) for 9 years. Rate of joint space loss and risk of arthroplasty due to meniscal tears and/or extrusion were determined by multivariate modeling. Prevalence of baseline medial meniscus tears was 21.3% and lateral tears was 12.8%; 26.9% had medial meniscal extrusion (79.6%, <2 mm; 20.4%, +2 mm) and 5.4% had lateral extrusion (75.9%, <2 mm; 24.1%, +2 mm). Median medial joint space loss was 0.06 mm/y and lateral was 0.05 mm/y. Medial tears regardless of extrusion were associated with accelerated medial joint space loss (additional mean, 0.05 mm/y; P = .001). Lateral tears were associated with accelerated lateral joint space loss (additional 0.09 mm/y; P < .001) as was lateral extrusion (additional 0.10 mm/y; P < .001). The yearly incidence of knee arthroplasty was 0.5% without lateral extrusion, 1.5% with extrusion less than 2.0 mm, and 3.7% with extrusion greater than or equal to 2.0 mm. Both medial and lateral tears accelerate joint space loss in middle-aged adults. Lateral meniscal extrusion further accelerates joint space loss and increases risk of progression to TKA within 9 years.     

Relevance of history of injury to the diagnosis of meniscal tears.

A consecutive series of 217 arthroscopic meniscectomies has been reviewed in order to investigate the incidence of significant meniscal lesions without obvious precipitating injury. There were 10 bucket handle tears out of 117 (9%) with a mean age of 32 years with no significant injury; 18 flap tears out of 69 (26%) with a mean age of 40 years; and 7 out of 19 (37%) radial tears with a mean age of 36 years also had no significant injury. This study indicates that the absence of a history of injury in the young patient with a symptomatic knee does not exclude significant meniscal tears, such as a bucket handle, and therefore has implications for history taking and diagnosis.     

Microvasculature of the human medial meniscus: operative findings.

The purpose of our study was to weigh the probability of a successful meniscus repair on the basis of the microvasculature of the human medial meniscus. In a series of 105 patients who underwent an anterior cruciate ligament reconstruction between January 1985 and December 1986, we chose the 40 patients who had a subtotal medial meniscectomy (38%) to study the microvasculature of the human medial meniscus adequately; the other patients had either an intact meniscus (23%), a meniscus repair (29%), or an already removed meniscus (10%). Forty medial menisci, from 40 male patients with an average age of 27 years, having an anterolateral and/or anteromedial chronic knee laxity and an associated meniscal pathology, were subdivided into two groups: (a) 20 tears restricted to the posterior horn, and (b) 20 bucket-handle tears observed under light microscopy. Meaningful capillary plexuses penetrating into the meniscal stroma were found in 18 of 40 menisci (45%). They were easier to identify in posterior horn tears (55%) than in bucket-handle tears (35%), and were found especially in younger patients (22 years on the average). Therefore, we encourage meniscus repairs even in chronic tears, particularly in younger patients and in posterior-horn tears.     

Clinical aspects of the detection of early arthrosis. Degenerative changes of the menisci of the knee joint

In a series of 420 persons the knee and hip joints were examined anamnestically and clinically. From this series, 146 persons were selected for further examination of one knee joint by means of magnetic resonance imaging (MRI) on a 1.5 Tesla Magnetom; there was a wide range of indications. Only four MRIs showed no pathological findings in the cruciate ligaments, cartilage surfaces, or menisci. Fifty-one menisci showed grade 3 degenerative changes. In 29 cases (57%), isolated horizontal tears were found, in 1 case (2%) an isolated vertical tear, and in 3 cases (6%) combined horizontal and vertical tears. The correlation of the degenerative changes in the medial meniscus and age was significant (P = 0.01). There was no correlation between the degenerative changes of the medial meniscus and femoral or tibial changes of the cartilage. In this series, there was no significant connection between degenerative changes of the medial meniscus and the previously accepted clinical symptomatology.     

Internal derangement of the knee: diagnosis by arthrography, arthroscopy, and arthrotomy

Three hundred eighty-four cases involving all patients with meniscal or anterior cruciate ligament tears were examined surgically by 16 orthopedic surgeons over two distinct 12-month periods. The incidence of both menisci (ipsilateral knee) torn was 3.9%, and the ratio of medial to lateral meniscal tears was 2.7:1. Twelve percent of cases had tears of the anterior cruciate ligament, 70% of which were found with a concomitant medial meniscus tear. Arthrography was completely accurate in 73.2% of cases, and arthroscopy was accurate in 94.9%. When clinical impression, arthrography, and arthroscopy were combined, the overall diagnostic accuracy was 96.8%.     

The accuracy of joint line tenderness by physical examination in the diagnosis of meniscal tears

Purpose: The purpose of this study was to document the accuracy of joint line tenderness in the diagnosis of meniscal tears. Type of Study: Prospective cohort study. Methods: There were 104 male recruits (age range, 18 to 20 years; mean, 19.2 years) with suspected meniscal lesions who underwent arthroscopy. A thorough history and physical examination was performed on each patient by a physician with 4 years’ experience on arthroscopic knee surgery. Twenty-six (25%) patients sustained injuries while in the Turkish Army, and 78 patients (75%) sustained injuries before they came to the army. On physical examination, assessment of joint line tenderness at the lateral and medial joint lines was performed with the patient’s knee flexed 90°. The accuracy, sensitivity, specificity, and positive and negative predictive values of joint line tenderness for medial and lateral sides were calculated based on arthroscopic findings. Results: In 104 knees, the diagnosis was correct in 71 (68%) and incorrect in 33 (32%) knees. A total of 37 medial meniscal tears and 27 lateral meniscal tears were identified at arthroscopy. Other pathology included 11 anterior cruciate ligament (ACL) tears, 5 medial femoral chondral lesions, 4 chondromalacia patellae, and 1 medial plica. No discernable abnormalities were seen in 21 knees. A preoperative diagnosis of a medial meniscal tear was made in 54 knees and 32 were confirmed at arthroscopy. A lateral meniscus tear was suspected in 27 knees and confirmed in 25. Five medial meniscus and 2 lateral meniscus tears were seen at arthroscopy. These had not been suspected with tenderness over the joint line. The accuracy of the test was lower with the presence of ACL lesions and condromalacia patella. Conclusions: I concluded that joint line tenderness as a test for lateral meniscal tears is accurate (96%), sensitive (89%), and specific (97%). However, for medial meniscal tears, rates are lower.     

Meniscal Root Tears

Meniscus root tears are a specific type of meniscal injury that have gained attention over the past 5 years and have been reported to account for 10% to 21% of all meniscal tears, affecting nearly 100,000 patients annually. Meniscal root tears either are defined as an avulsion of the insertion of the meniscus attachment or complete radial tears that are located within 1 cm of the meniscus insertion. Biomechanical studies have demonstrated that meniscal root injuries interrupt the continuity of the circumferential fibers, and hence lead to failure of the normal meniscal function to convert axial loads into transverse hoop stresses. The most common presenting symptoms in meniscal root tears are posterior knee pain and joint line tenderness, especially with deep squatting.Another common symptom is a popping sound heard while participating in light activities such as ascending stairs or squatting. Magnetic resonance imaging signs of medial meniscus root tears include: (1) medial meniscal extrusion of ≥3 mm in a coronal section; (2) high signal indicating a disruption of the posterior meniscal root region in an axial view; and (3) a “ghost sign,” which is the absence of an identifiable meniscus in the sagittal plane, or increased signal replacing the normally dark meniscal tissue signal at the posterior root attachment. Active patients, regardless of age, should be referred early and considered for a meniscal root repair. Indications for a meniscal root repair include acute, traumatic root tears in patients with nearly normal or normal cartilage and chronic symptomatic root tears in young or middle-aged patients without significant preexisting osteoarthritis.Meniscal root repair has been demonstrated to have high satisfaction rates and superior outcomes to arthroscopic meniscectomy for root tears. To restore the function of the meniscus after medial meniscus root tears, a transosseous meniscal root repair technique is most commonly used. The advantage of this technique is the ability to reduce and fix the meniscal root to the broad anatomic footprint to maximize its healing potential. In addition, the transtibial tunnels may contribute to the release of biological factors that can enhance the healing of the meniscal root repair.     

Physicians' accuracy and interrator reliability for the diagnosis of unstable meniscal tears in patients having osteoarthritis of the knee.

OBJECTIVE: To determine clinicians' accuracy and reliability for the clinical diagnosis of unstable meniscus tears in patients with symptomatic osteoarthritis of the knee. DESIGN: A prospective cohort study. SETTING: A single tertiary care centre. PATIENTS: One hundred and fifty-two patients with symptomatic osteoarthritis of the knee refractory to conservative medical treatment were selected for prospective evaluation of arthroscopic debridement. INTERVENTION: Arthroscopic debridement of the knee, including meniscal tear and chondral flap resection, without abrasion arthroplasty. OUTCOME MEASURES: A standardized assessment protocol was administered to each patient by 2 independent observers. Arthroscopic determination of unstable meniscal tears was recorded by 1 observer who reviewed a video recording and was blinded to preoperative data. Those variables that had the highest interobserver agreement and the strongest association with meniscal tear by univariate methods were entered into logistic regression to model the best prediction of resectable tears. RESULTS: There were 92 meniscal tears (77 medial, 15 lateral). Interobserver agreement between clinical fellows and treating surgeons was poor to fair (kappa < 0.4) for all clinical variables except radiographic measures, which were good. Fellows and surgeons predicted unstable meniscal tear preoperatively with equivalent accuracy of 60%. Logistic regression modelling revealed that a history of swelling and a ballottable effusion were negative predictors. A positive McMurray test was the only positive predictor of unstable meniscal tear. "Mechanical" symptoms were not reliable predictors in this prospective study. The model was 69% accurate for all patients and 76% for those with advanced medial compartment osteoarthritis defined by a joint space height of 2 mm or less. CONCLUSIONS: This study underscored the difficulty in using clinical variables to predict unstable medial meniscal tears in patients with pre-existing osteoarthritis of the knee. The lack of interobserver agreement must be overcome to ensure that the findings can be generalized to other physician observers.     

The triple PCL sign: bucket handle tears of both medial and lateral menisci in a chronically ACL-deficient knee

Bucket handle tears of both menisci in the setting of acute or chronic anterior cruciate ligament (ACL) tears of the same knee have rarely been reported in the literature. This article presents a case of a bucket handle tear affecting both the medial and lateral menisci in a patient with chronic ACL rupture. Both bucket handle tears were displaced and locked in the intercondylar notch. A new magnetic resonance image (MRI) sign suggested on sagittal view is called the triple PCL sign, comprising the intact posterior cruciate ligament (PCL) and the 2 displaced fragments in the intercondylar notch from the two bucket handle tears. The precise diagnosis of this condition is of obvious importance for optimal operative planning. While finding the displaced fragment from the medial meniscus is expected to cause the double PCL sign, the torn ACL may have made it easier to visualize the bucket handle tear of the lateral meniscus in the same sagittal plane as the PCL. Only 5 other reports mention bimeniscal bucket handle tears of both the medial and lateral menisci in association with an ACL tear. None have shown the suggested triple PCL sign because of lack of overlap between the 2 bucket handle tears in the coronal plane while lying in the intercondylar notch causing them not to fall in the same sagittal plane. Our patient showed some overlap between the 2 meniscal fragments while lying in the notch to create the triple PCL sign on sagittal MRI.     

Arthroscopic treatment of cysts of the menisci. A preliminary report

A retrospective clinical study evaluated the results of arthroscopic management of cysts of the menisci. From 1979 to 1984, 24 patients with a diagnosis of meniscal cysts associated with tears of the semilunar cartilage were treated with partial meniscectomy and cyst decompression. The mean age was 29.9 years (range, 14-52 years). Each patient had tenderness over the joint line with a palpable mass. There were 25 cases of meniscal cysts, with one patient having a bilateral cyst. Twenty-two cysts involved the lateral meniscus, and three cysts were on the medial side of the knee. The follow-up period ranged from 16 to 48 months (mean, 33.5 months). All patients had a meniscal tear; most tears were either horizontal or transverse, with or without flap formation. The pathology was in the middle or anterior one-third of the meniscus. The arthroscopic surgery consisted of partial excision of the meniscal tear, leaving a peripheral rim at times, coupled with aspiration of the cyst material or manipulation of its contents into the joint cavity. No cyst recurred, and in every patient except one, preoperative symptoms disappeared. All patients but one were satisfied with the results. Two patients had a second arthroscopy, and no evidence of instability of the peripheral rim was found.     

MR imaging of the knee: clarification of its role

In an attempt to further delineate the role of magnetic resonance (MR) imaging in evaluating knee pathology, a retrospective study of 60 patients who underwent MR scanning before arthroscopy was undertaken. For medial meniscus tears, the sensitivity of MR imaging was 97% whereas its specificity was 77%. For lateral meniscus tears, MR imaging was 90% sensitive and 87% specific. The positive predictive value of MR imaging was 85% for medial meniscus tears and only 79% for lateral meniscus tears. The negative predictive value was 95% for the medial meniscus and 94% for the lateral meniscus. MR imaging had an accuracy of 93% in assessing anterior cruciate ligament pathology also. These results begin to clarify the role of MR imaging in evaluating intraarticular knee pathology. Grade III signals represented tears at arthroscopy more than 90% of the time. False-positive results occurred more frequently than false negative results did. The high negative predictive value of MR imaging indicates that with a negative MR image, the orthopaedist can reliably conclude that no meniscal pathology is present. MR imaging is a useful diagnostic tool; however, it should be used selectively and in conjunction with the clinical examination in evaluating internal derangements of the knee.     

Stage-based treatment by partial meniscectomy, meniscal refixation and transplantation

Clinical and experimental studies have demonstrated that the meniscus is important for normal knee function. Loss of meniscus results in abnormal load transmission across the knee and may lead to degenerative joint disease. Preservation of meniscal tissue is therefore important. About 10 % of all meniscal tears are repairable. The most successful repairs occur in younger patients who have an acute, vertical tear in the vascular portion of the meniscus. Currently, arthroscopic meniscal repair procedures include the inside-out, the outside-in and the all-inside technique. Vertical suture techniques are superior to horizontally placed sutures. From a biomechanical point of view, 2-0 to 1 sutures are recommended for suture repair. Various meniscus implants are also available for meniscal repair. The initial fixation strength of the implants is lower compared to vertical sutures. A combination of suture techniques and implants might be a treatment option in posterior meniscal lesions. The collagen meniscus implant has been designed to support tissue ingrowth after segmental medial meniscectomy. Although fibrocartilage matrix formation has been shown, long-term clinical follow-ups are still required. Meniscal allograft transplantation may be indicated in limited situations. Younger patients with meniscal deficiency due to previous meniscectomy who have only early arthrosis, normal axial alignment, and a stable knee may currently considered appropriate candidates for meniscal transplantation.     

Altered signal intensity in the posterior horn of the medial meniscus: an MR finding of questionable significance

Introduction MR imaging has emerged as an important modality in the non-invasive evaluation of osseous and soft-tissue structures in the post-traumatic knee. However, it is sometimes impossible to determine with confidence if a focus of high signal intensity in the meniscus is confined to the substance of the meniscus or if it extends to involve the joint surface. This is a critical differentiation because the latter represents meniscal tears that can be found and treated arthroscopically, whereas the former represents degeneration, intrasubstance tears or perhaps normal variants that are not amenable to arthroscopic intervention. The aim of this study was to investigate the occurrence of such borderline findings in relation to the posterior horn of the medial meniscus and to correlate the arthroscopic results.Materials and methods Sixty-four patients with suspected post-traumatic internal derangements of the knee who underwent MR imaging prior to arthroscopy were evaluated retrospectively. There were 48 men and 16 women. Their mean age was 28.2 years.Results Tears of the posterior horn of the medial meniscus were diagnosed unequivocally (grade 3 signal) in 18 patients and equivocally (grade 2/3 signal) in 10 patients. Arthroscopic correlation revealed 16 tears (89%) in the unequivocal group and only 1 tear (10%) in the equivocal group.Conclusion A meniscal tear is unlikely when MR shows a focus of high signal intensity in the posterior horn of the medial meniscus that does not unequivocally extend to involve the inferior or superior joint surface. An appropriate trial of conservative treatment is recommended in such questionable cases. MR is a useful diagnostic tool—however, it should be used selectively, and in conjunction with history and clinical examination in evaluating internal derangements of the knee.