Torn Discoid Lateral Meniscus Research Articles

Facteurs de risque d’arthrose après méniscectomie partielle sur ménisque discoïde latéral

IntroductionPartial meniscectomy has been preferred in the treatment of discoid lateral meniscus (DLM) with tear, rather than total or subtotal meniscectomy, which could lead to late radiographic degenerative changes. HypothesisOne or more risk factors contribute to radiographic progression of osteoarthritis after partial meniscectomy of DLM tear. Material and methodsInclusion criteria were consecutive patients who underwent arthroscopic surgeries for DLM tear from January 2005 to December 2010 by one surgeon. Exclusion criteria were pre-operative osteoarthritis with KL grade 3 or more, osteochondritis dissecans, minimal width of meniscal remnant less than 6mm after meniscectomy, meniscal repair of an unstable discoid meniscus, age over 60 years, loss to follow-up for a minimum of 5years and simultaneous surgery on articular cartilage or anterior cruciate ligament. According to the KL grade at the last follow-up, all enrolled knees were sorted into no progression to knee osteoarthritis (KL grade 1 or 2 – NOA) and progression to osteoarthritis (KL grade 3 or 4 – POA) groups. Multivariate logistic regression was used to analyze the risk factors of high-grade osteoarthritis. ResultsIn comparison with NOA group (n=135) and POA group (n=67), prolonged symptom duration, increased relative percentage of DLM thickness (RPDT) and the presence of horizontal tear were significant risk factors. The presence of horizontal tear (P=0.048, adjusted OR=19.364) was the strongest predictor, compared with prolonged symptom duration (P=0.030, adjusted OR=1.150) and increased RPDT (P=0.003, adjusted OR=1.377). DiscussionHorizontal tear, prolonged symptom duration, and increased RPDT are significant risk factors for radiographic progression to high-grade osteoarthritis after partial meniscectomy of DLM tear with a minimum follow-up of 5years. Level of evidenceIII, case-control study.

Risk factors for radiographic progression of osteoarthritis after partial meniscectomy of discoid lateral meniscus tear

IntroductionPartial meniscectomy has been preferred in the treatment of discoid lateral meniscus (DLM) with tear, rather than total or subtotal meniscectomy, which could lead to late radiographic degenerative changes. HypothesisOne or more risk factors contribute to radiographic progression of osteoarthritis after partial meniscectomy of DLM tear. Material and methodsInclusion criteria were consecutive patients who underwent arthroscopic surgeries for DLM tear from January 2005 to December 2010 by one surgeon. Exclusion criteria were preoperative osteoarthritis with KL grade 3 or more, osteochondritis dissecans, minimal width of meniscal remnant less than 6mm after meniscectomy, meniscal repair of an unstable discoid meniscus, age over 60years, loss to follow-up for a minimum of 5years and simultaneous surgery on articular cartilage or anterior cruciate ligament. According to the KL grade at the last follow-up, all enrolled knees were sorted into no progression to knee osteoarthritis (KL grade 1 or 2 – NOA) and progression to osteoarthritis (KL grade 3 or 4 – POA) groups. Multivariate logistic regression was used to analyze the risk factors of high-grade osteoarthritis. ResultsIn comparison with NOA group (n=135) and POA group (n=67), prolonged symptom duration, increased relative percentage of DLM thickness (RPDT) and the presence of horizontal tear were significant risk factors. The presence of horizontal tear (P=0.048, adjusted OR=19.364) was the strongest predictor, compared with prolonged symptom duration (P=0.030, adjusted OR=1.150) and increased RPDT (P=0.003, adjusted OR=1.377). DiscussionHorizontal tear, prolonged symptom duration, and increased RPDT are significant risk factors for radiographic progression to high-grade osteoarthritis after partial meniscectomy of DLM tear with a minimum follow-up of 5years. Level of evidenceIII, case-control study.

Does high location and thickness of the Wrisberg ligament affect discoid lateral meniscus tear type based on peripheral detachment?

BackgroundThe aim of this study was to evaluate the relationship between discoid lateral meniscus (DLM) types based on peripheral detachment and anatomic features of Wrisberg ligament (WL) such as location and thickness based on magnetic resonance image (MRI). MethodsA total of 322 knees in 292 patients were reviewed. Patients were divided into four DLM types according to peripheral detachment: no shift (type 1), anterocentral shift (type 2), posterocentral shift (type 3) and central shift (type 4). We reviewed all MRI concentrating on the presence, location (high or low location), running angle, thickness of WL, and WL/posterior cruciate ligament (PCL) thickness ratio. The relationship between DLM types and anatomic features of WL were analyzed using one-way analysis of variance and chi-square test. ResultsAccording to DLM types based on peripheral detachment, 149 knees were type 1, 38 were type 2, 79 were type 3, and 56 were type 4. Among the 322 knees, 302 (93.8%) had WL on MRI. In DLM patients, type 3 showed a statistically significant (P<0.001) relationship with high location of WL. In addition, type 3 had significantly larger (P<0.0001) running angle of WL, thicker (P<0.0001) WL, and higher (P<0.0001) WL/PCL ratio compared to other types. ConclusionA high location and thick WL are related to posterocentral shift type of DLM based on peripheral detachment. Based on our results, the high location and thick WL might provide information to surgeons in predicting the direction of peripheral detachment in symptomatic DLM patients.

Curative effect of arthroscopic surgery on knee joint disease in children

Objective To analyze the clinical characteristics of children with knee joint diseases and discuss the curative effect of arthroscopy. Methods Eighty-nine children with knee joint diseases in Department of Orthopedics, the First Affiliated Hospital of Xinxiang Medical University from October 2012 to October 2015 were selected, and they were given knee arthroscopic surgery according to the disease types and characteristics, such as meniscal suture, suture plus angioplasty and synovectomy etc.All the symptoms, signs and the joint functions were recorded preoperatively and postoperatively.At the end of follow-up, surgical results were analyzed according to Lysholm score and International Knee Documentation Committee Knee evaluation form(IKDC) classification standard. Results The patients with discoid meniscus tear were the most, accounting for 55.55%(55/99 knees). All patients were followed up for 6-30 months(the average time was 21 months) to find that all symptoms were relieved or disappeared within 1 year after operation.The outcome was evaluated according to the Tegner knee function: 76 knees (76.76%) were markedly effective, 16 knees (16.16%) were effective, 6 knees (6.06%) were invalid and 1 knee (1.01%) was poor, and the excellent rate was 92.92%.The curative effect was evaluated according to Lysholm knee function score and IKDC score at the last follow-up.The Lysholm score in preoperation[(52.46±4.79) scores] improved to (96.52±3.97) scores in postoperation, and the difference was significant (t=-36.24, P<0.05); the IKDC score in preoperation[(46.52±10.25) scores] improved to (90.67±5.89) scores in postoperation, and the difference was significant (t=-50.69, P<0.05). There was no joint infection, blood vessel or nerve damage and so on. Conclusions Meniscus tear is common in children with knee joint diseases, and most common is discoid lateral meniscus tear, and arthroscopy can have satisfactory outcome, with no obvious complications.Therefore, arthroscopic surgery is an ideal method for surgical treatment of children with knee joint disease. Key words: Knee joint disease; Discoid meniscus; Child; Arthroscope; Meniscus suture

Anatomical Knee Variants in Discoid Lateral Meniscal Tears.

Background:Discoid lateral meniscus was a common meniscal dysplasia and was predisposed to tear. There were some anatomical knee variants in patients with discoid lateral meniscus. The aim of this study was to analyze the relationship between anatomical knee variants and discoid lateral meniscal tears.Methods:There were totally 125 cases of discoid lateral meniscus enrolled in this study from February 2008 to December 2013. Eighty-seven patients who underwent arthroscopic surgery for right torn discoid lateral meniscus were enrolled in the torn group. An additional 38 patients who were incidentally identified as having intact discoid lateral menisci on magnetic resonance imaging (MRI) findings were included in the control group. All patients were evaluated for anatomical knee variants on plain radiographs, including lateral joint space distance, height of the lateral tibial spine, height of the fibular head, obliquity of the lateral tibial plateau, squaring of the lateral femoral condyle, cupping of the lateral tibial plateau, lateral femoral condylar notch, and condylar cutoff sign. The relationship between anatomical variants and meniscal tear was evaluated. These anatomical variants in cases with complete discoid meniscus were also compared with those in cases with incomplete discoid meniscus.Results:There were no significant differences between the two groups in lateral joint space distance (P = 0.528), height of the lateral tibial spine (P = 0.927), height of the fibular head (P = 0.684), obliquity of the lateral tibial plateau (P = 0.672), and the positive rates of squaring of the lateral femoral condyle (P = 0.665), cupping of the lateral tibial plateau (P = 0.239), and lateral femoral condylar notch (P = 0.624). The condylar cutoff sign was significantly different between the two groups, with the prominence ratio in the torn group being smaller than that in the control group (0.74 ± 0.11 vs. 0.81 ± 0.04, P = 0.049). With the decision value of the prominence ratio (0.78) in predicting discoid lateral meniscal tear, the sensitivity and specificity of the cutoff sign were 66% and 71%, respectively. There were no significant differences in radiographic variants between the complete and incomplete discoid lateral meniscal groups.Conclusions:The condylar cutoff sign observed on the tunnel view of the radiograph is helpful in predicting meniscal tear in adult patients with discoid lateral meniscus. As for these patients, further MRI test is recommended.

Locked knee in children owing to torn discoid lateral meniscus: the role of arthroscopic management

Background Discoid meniscusis a relatively rare congenital anatomical abnormality in which the meniscus is discoid rather than semilunar in shape. A torn discoid lateral meniscus (DLM) can be a potential cause of mechanical symptoms in children; moreover, it is considered the commonest reason for arthroscopic interventions performed on children. Hypothesis Arthroscopic reshaping of the meniscus (meniscoplasty) by partial excision of the central part achieves good results in these patients. Patients and methods Twenty patients (20 knees) presenting with symptomatic torn DLM were included in the study. The age ranged from 3 to 11 years, with a mean of 7.2 years. Five of them were males and 15 were females. Seventeen of them had locked knee owing to displaced bucket handle tear of DLM. Two patients had complex tear of DLM, whereas only one patient had a longitudinal cleavage tear. All the cases experienced knee pain and swelling. Clinical evaluation of the patients was done according to the subjective and objective International Knee Documentation Committee (IKDC) 2000 forms, and Lysholm knee score. Moreover, radiological evaluation was performed using plain radiographs and MRI. All patients were managed by reshaping of the meniscus by arthroscopic central partial meniscectomy regardless of the tear type. The duration of follow-up ranged from 22 to 36 months, with a mean of 26.4 months. Results All the patients showed dramatic improvement postoperatively. The average postoperative subjective IKDC score was 76% as compared with 29.25% preoperatively. Postoperative IKDC objective grade was A in six (30%) cases and B in 13 (65%) cases at the end of follow-up, as compared with the preoperative grade assessment, which was D in six (30%) cases and C in 14 (70%) cases, with statistically highly significant results (P Conclusion Torn DLM can be a potential cause of symptomatic knee pain and effusion in children and should not be overlooked. Arthroscopic central partial meniscectomy (meniscoplasty) can give good results in these cases.

Collagenous Ultrastructure of the Discoid Meniscus: A Transmission Electron Microscopy Study

Background: The collagen ultrastructure of the discoid lateral meniscus (DLM) has not been precisely defined. Purpose: To investigate the ultrastructure of the DLM, focusing on its collagen fibers, and to compare the collagen net architecture between intact and torn DLMs using the Collagen Meniscal Architecture (CMA) scoring system. Study Design: Descriptive laboratory study. Methods: Thirty specimens were taken from 30 patients with a diagnosis of a complete DLM using a 1-piece technique. The collagen ultrastructure of the DLMs was assessed with transmission electron microscopy. To evaluate the meniscal ultrastructure, the degree of collagen disruption, intrafibrillar edema, loss of banding, degree of collagen packing, and fibril size variability were assessed and graded from 1 (normal) to 3 (severe disarray) according to the CMA scoring system. The DLM specimens were divided into 3 groups according to the intrasubstance tear: the intact group (group I) had no tear; the simple tear group (group S) had a radial, longitudinal, or horizontal tear; and the complicated tear group (group C) had a complicated horizontal tear. Intact normal meniscus specimens (group N) were used as the control group. Results: There were 10 specimens in group I, 8 in group S, 12 in group C, and 13 in group N. In group I, there were 5 grade 1 and 5 grade 2 menisci; group S had 2 grade 1, 3 grade 2, and 3 grade 3 menisci; group C had 1 grade 1, 4 grade 2, and 7 grade 3 menisci; and group N had 4 grade 1, 7 grade 2, and 2 grade 3 menisci. A significant difference in the CMA score was observed between the 4 groups (P = .009). The median CMA score was significantly lower in group I (2; range, 1-4) than in group S (4; range, 2-7) (P = .041) and group C (4.25; range, 1.5-7) (P = .018). No significant difference was found between groups S, C, and N. Conclusion: Variability existed in the collagen ultrastructure of the DLM, and some DLMs showed a nearly normal ultrastructural pattern. The degree of density and disorganization of the collagen architecture in the DLM was related to the tear. Clinical Relevance: The study results might provide a histological background for partial meniscectomy in the treatment of a symptomatic DLM.

Meniscus transplantation in skeletally immature patients.

Meniscal pathology in skeletally immature patients includes meniscal tears and discoid lateral meniscus. Total or subtotal meniscectomy may occur in patients with discoid lateral meniscus or severe meniscal tears. Meniscal transplantation may be an option in skeletally immature patients status after total or subtotal meniscectomy with knee symptoms or dysfunction. This study focuses on the surgical technique and short-term outcomes of meniscus transplantation in skeletally immature patients. We reviewed our clinical database for skeletally immature patients who had undergone meniscus transplantation with a minimum of 2 years of follow-up. Patients were contacted, invited for a physical exam, and asked to complete a Pedi-IKDC, Lysholm, and Tegner outcomes questionnaire. The study protocol was approved by the responsible institutional review board. Three patients (two females/one male) were eligible for the study, each of whom responded to our invitation indicating availability for physical exam and questionnaire. Two patients had undergone subtotal discoid meniscus resection, leading to early lateral compartment degeneration. One patient developed advanced degeneration after a delay in treatment for a medial bucket-handle tear associated with anterior cruciate ligament rupture. The mean age of the patients at the time of surgery was 12.6±2.3 years. At a mean follow-up of 31±20 months, the mean Pedi-IKDC score was 68.3±4, the mean Lysholm was 55.7±22.3, and the median Tegner was 7 points. There were no indications of growth deformity during the regular postoperative radiological assessments. One patient required subsequent lysis of adhesions along the lateral mini arthrotomy and mobilization under anesthesia. The other two patients were able to return to sports at the same level as before meniscus transplantation and were able to do so within 9 months postoperatively. Over-resection of discoid menisci as well as untreated meniscus injury, the latter typically in conjunction with ligamentous instability, can lead to advanced cartilage degeneration and recalcitrant complaints necessitating surgical treatment before skeletal maturity. We were able to show that meniscus transplantation in skeletally immature patients leads to acceptable clinical outcomes without growth deviation. IV.

Cost effectiveness of meniscal allograft for torn discoid lateral meniscus in young women

ABSTRACTObjective: A discoid meniscus is more prone to tears than a normal meniscus. Patients with a torn discoid lateral meniscus are at increased risk for early onset osteoarthritis requiring total knee arthroplasty (TKA). Optimal management for this condition is controversial given the up-front cost difference between the two treatment options: the more expensive meniscal allograft transplantation compared with standard partial meniscectomy. We hypothesize that meniscal allograft transplantation following excision of a torn discoid lateral meniscus is more cost-effective compared with partial meniscectomy alone because allografts will extend the time to TKA.Methods: A decision analytic Markov model was created to compare the cost effectiveness of two treatments for symptomatic, torn discoid lateral meniscus: meniscal allograft and partial meniscectomy. Probability estimates and event rates were derived from the scientific literature, and costs and benefits were discounted by 3%. One-way sensitivity analyses were performed to test model robustness.Results: Over 25 years, the partial meniscectomy strategy cost $10,430, whereas meniscal allograft cost on average $4040 more, at $14,470. Partial meniscectomy postponed TKA an average of 12.5 years, compared with 17.30 years for meniscal allograft, an increase of 4.8 years. Allograft cost $842 per-year-gained in time to TKA.Conclusion: Meniscal allografts have been shown to reduce pain and improve function in patients with discoid lateral meniscus tears. Though more costly, meniscal allografts may be more effective than partial meniscectomy in delaying TKA in this model. Additional future long term clinical studies will provide more insight into optimal surgical options.

Simultaneous Osteoperiosteal Autologous Iliac Crest Graft and Lateral Meniscus Allograft Transplantation for Osteochondral Lesion with Bony Defect and Lateral Discoid Meniscus Tear.

The optimal treatment for combined osteochondritis dissecans (OCD) with considerable bony defect of the lateral femoral condyle (LFC) and torn discoid lateral meniscus is unclear. We present a case of a 15-year-old female who was a gymnast and had a large OCD lesion in the LFC combined with deficiency of the lateral meniscus. The patient underwent the "one-step" technique of osteoperiosteal autologous iliac crest graft and lateral meniscus allograft transplantation after a failure of meniscectomy with repair at another hospital. Twenty-four months postoperatively, clinical results were significantly improved. Follow-up imaging tests and second-look arthroscopy showed well incorporated structured bone graft and fibrous cartilage regeneration as well as stabilized lateral meniscus allograft. She could return to her sport without any pain or swelling. This "one-step" surgical technique is worth considering as a joint salvage procedure for massive OCD lesions with torn discoid lateral meniscus.

Meniscoplasty for lateral discoid meniscus tears: Long-term results of 14 cases

IntroductionDiscoid lateral meniscus lesions are relatively rare. The objective of this study was to determine the long-term results of 14 cases of discoid lateral meniscus tears treated by arthroscopic meniscoplasty between July 1991 and May 2009, and to assess the development of osteoarthritis in the lateral compartment. MethodsThe series consisted of 10 patients (14 knees): 3 girls under the age of 15, 3 men and 4 women aged from 16 to 47 years (mean age: 31.4±11.1 years). The main reason for consultation was pain in 10 cases, locking in 2 cases and pain associated with locking in 2 cases. The diagnosis was confirmed preoperatively by MRI in 10 cases, CT-arthrography in 1 case and arthrography in 3 cases. The indication for surgery was made because of a symptomatic discoid lateral meniscus. All cases were treated by arthroscopic meniscal reshaping. Functional results were evaluated using the Lysholm–Tegner, IKDC, KOOS and satisfaction scores. Radiological results were evaluated based on the modified Alhbäck classification for osteoarthritic (OA) changes. ResultsNo complications were found. Two patients were lost to follow-up. The remaining eight patients (12 knees) were reviewed at a mean of 157.5±72.1 months (61–276). The mean Lysholm–Tegner score was 88.9±10.6 points (67–100), the mean KOOS was 92.4±9.5 (65–100) and the mean IKDC score was 85.4±16.5 points (65–100). All eight of the reviewed patients were satisfied or very satisfied with the result. Radiological analysis found that five knees had no signs of OA, five knees had stage 1, one had stage 2 and one had stage 3. At last follow-up, no patient had been reoperated. ConclusionMeniscoplasty of discoid lateral meniscus tears leads to excellent long-term functional results despite signs of osteoarthritic changes in the lateral compartment of the knee. Level of evidenceIV (retrospective study).

Short-term effects of discoid lateral meniscectomy on the axial alignment of the lower limb in adolescents.

A discoid lateral meniscus in the knee is more common in Asian populations. The aim of this study was to evaluate the influence of arthroscopic meniscectomy of the discoid lateral meniscus on the axial alignment of the lower limb in adolescents (younger than twenty years of age). We retrospectively reviewed the data from 298 adolescent patients (younger than twenty years of age) who underwent arthroscopic treatment in our center from 2004 to 2013. Patients were divided into three groups according to the meniscus type: torn discoid lateral meniscus (Group A), torn nondiscoid lateral meniscus (Group B), and nondiscoid lateral meniscus without a tear (Group C). The tibiofemoral angle (TFA) and mechanical axis deviation (MAD) of both lower limbs were examined on standing anteroposterior radiographs before and after arthroscopy. The preoperative TFA and MAD of the ipsilateral lower limbs demonstrated significantly more varus in Group A than in Group B (p < 0.001) or Group C (p < 0.001) after we controlled for the contralateral lower limbs as a covariate factor. Moreover, the TFA and MAD of the ipsilateral knees were significantly reduced (indicating a reduction in varus inclination) postoperatively, as compared with preoperatively, in Group A (p < 0.001) and Group B (p < 0.001), with no difference between the preoperative and postoperative values in Group C (p > 0.01), after we controlled for the contralateral lower limb as the covariate factor. Additionally, the reductions in the TFA and MAD (varus inclination) in Group A were significantly greater than those observed in Group B (p < 0.001). The axial alignment of the lower limb in adolescents (younger than twenty years of age) with a torn discoid lateral meniscus was altered immediately after arthroscopic meniscectomy: the varus deformity was significantly reduced, and a valgus inclination developed in some of these patients. The valgus inclination was more pronounced in the patients with a torn discoid lateral meniscus compared with those with a torn nondiscoid lateral meniscus.

Subtle Bucket-Handle Tear Of A Discoid Lateral Meniscus In A 6 Year Old Girl

We report a subtle bucket-handle tear of discoid lateral meniscus causing knee extension blockage in a 6 year old girl. This rare presentation should be recognised by all orthopaedic surgeons practising arthroscopic surgery.

Meniscus Allograft Transplantation for Discoid Lateral Meniscus: Clinical Comparison Between Discoid Lateral Meniscus and Nondiscoid Lateral Meniscus

This study was performed to compare the clinical results of meniscus allograft transplantation (MAT) after total meniscectomy in torn discoid lateral meniscus (DLM) and nondiscoid lateral meniscus (NLM). We conducted a retrospective study of 36 patients who underwent MAT. The discoid and nondiscoid groups consisted of 16 and 20 patients, respectively. The mean follow-up period was 32 months. We checked range of motion (ROM), visual analog scale (VAS) score, International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity score for clinical evaluation; magnetic resonance imaging (MRI) was checked for objective evaluation. The mean last follow-up VAS score, IKDC subjective score, Lysholm score, Tegner activity score, and subjective satisfaction of the patient were not significantly different between the discoid group and the nondiscoid group. The ROM of the discoid group was significantly decreased compared with that of the nondiscoid group (P < .05). Follow-up MRI was performed in 17 patients (9 from the discoid group and 8 from the nondiscoid group). Mean extrusion of the graft was 2.0 mm in the discoid group and 2.4 mm in the nondiscoid group (P = .344). Relative percentage of extrusion (RPE) was 22.8% in the discoid group and 22.7% in the nondiscoid group (P = .519). According to the minimal 2-year follow-up observations, MAT in patients with a torn discoid meniscus is an effective method for reducing the pain caused by meniscal deficiency and improving the function of the knee joint. Level IV, therapeutic case series.

Discoid Lateral Meniscus Tears and Concomitant Articular Cartilage Lesions in the Knee

The purpose of this study was to investigate the relation between isolated discoid lateral meniscus (DLM) tears and the presence of articular cartilage lesions. From January 2010 to January 2012, 252 consecutive patients diagnosed with an isolated DLM tear during an arthroscopic procedure were included in this study. Demographic variables, including gender, age, body mass index (BMI), traumatic history, time course, and date of the DLM tear, were recorded. The relation between DLM tears and the presence of articular cartilage lesions was analyzed by the χ(2) test. Logistic regression analysis was used to analyze the relation between these variables and articular cartilage lesions. Of the patients with DLM tears, 67 (26.6%) also had articular cartilage lesions. The most common type of DLM tear was the complex tear (46.8%). The most common location of articular cartilage lesions was the lateral tibial plateau (11.6%). Lesions on the opposing articular surfaces of the lateral compartment and patellofemoral joint of the knee were found in 12 patients (4.8%) and 11 patients (4.4%), respectively. There were no significant differences in the incidences of articular cartilage lesions in patients with different types of DLM tears (P > .05). Gender (odds ratio [OR], 2.289; P= .012), BMI (OR, 1.991; P= .023), and time course (OR, 2.050; P= .034) were significantly associated with articular cartilage lesions. DLM tears were more common in the context of degenerative tears. There was no significant difference in the incidence of articular cartilage lesions among patients with different types of DLM tears. Female patients, patients with a BMI greater than 23.0 kg/m(2), or patients with a time course of greater than 6 months were more frequently observed to also have articular cartilage lesions. Level IV, therapeutic case series.

Familial discoid medial meniscus tear in three members of a family: a case report and review of literature.

Background. A discoid meniscus is a thickened variant of the normal C-shaped meniscus prone to injury. Discoid medial meniscal tears have rarely been reported within families and may suggest familial or developmental origins. Methods. We report the cases of two Caucasian brothers with symptomatic discoid medial meniscus tears. A literature review was conducted addressing discoid medial meniscus and cases of familial meniscus tears. Case Presentation. Physically active brothers presented with progressively worsening knee pain. MRI revealed medial meniscus tears in both brothers. The family history of medial meniscus tears in their mother and the discoid medial meniscus injuries found on arthroscopy suggested evidence for familial discoid medial meniscus tears. Conclusions. Discoid medial meniscus tears within a family have not been previously reported. Two cases of families with discoid lateral meniscus tears have been reported. Discoid medial meniscus is rare relative to the discoid lateral meniscus and predisposes children to symptomatic tears.

Does Torn Discoid Meniscus Have Effects on Limb Alignment and Arthritic Change in Middle-Aged Patients?

The purpose of the present study was to evaluate the characteristics of the discoid lateral meniscus in patients more than forty years of age. We studied whether a torn discoid lateral meniscus that has no treatment until middle age would increase the tendency of the knee to develop a varus deformity and investigated the correlation between torn discoid lateral meniscus and osteoarthritis. We retrospectively reviewed the records for 164 knees in 158 patients who were more than forty years old and who underwent a knee arthroscopic procedure from 1992 to 2007. The mean age at the time of surgery was fifty-two years. Comparative evaluation of the clinical and radiographic differences between the eighty-four patients with torn discoid lateral meniscus (Group A) and the seventy-four patients with a torn normally shaped lateral meniscus (Group B) was carried out. Preoperative standing anteroposterior radiographs, which were made for all patients, showed that varus deformity was more common in Group A than in Group B and that osteoarthritic changes in both the medial and lateral compartments were also more common in Group A. With regard to chondral injury, Outerbridge grade-3 or 4 involvement was identified in 46% of the knees in Group A and 18% of the knees in Group B. In the present study of middle-aged patients, those with a torn discoid lateral meniscus had a higher prevalence of varus knee deformity and a higher prevalence of osteoarthritis. Knees with a discoid lateral meniscus that have diminished valgus alignment should be monitored carefully with long-term follow-up because a discoid lateral meniscus may increase the risk for progression to degenerative knee osteoarthritis.

MRI findings with arthroscopic correlation for tear of discoid lateral meniscus: comparison between children and adults

Discoid lateral meniscus is more susceptible to tear than normal meniscus. A comparison study for tear types of discoid lateral meniscus between children and adults has not been reported. To compare tear type of surgically proven discoid lateral meniscus between adults and children, and to analyze diagnostic performance for tear type of discoid lateral meniscus using magnetic resonance imaging (MRI). Knee MR examinations of 53 children and 84 adults who had discoid lateral menisci identified at arthroscopic surgery were retrospectively evaluated with consensus by two radiologists for tear type including displacement of torn meniscus. MRI findings were compared with surgery as the reference standard. The difference of tear type and displacement of torn meniscus between children and adults in arthroscopic finding was analyzed using the Fisher's exact test or the Chi-squared test with Bonferroni's correction. At arthroscopy, complex tear (children, n = 22; adults, n = 56) and peripheral tear (children, n = 17; adults, n = 8) differed significantly between children and adults (P = 0.006 for complex tear, P = 0.002 for peripheral tear). Displacement of torn meniscus was seen in 28 cases of children and 41 cases of adults, not a statistically significant difference. In children, the positive predictive value (PPV) for horizontal tears was 90%, for peripheral tears 60%, and for complex tears 57%. PPV in adults for horizontal tears was 78%, peripheral tears 25%, and for complex tears 89%. Complex tears were more commonly found in adults than children and peripheral tears were more commonly found in children than adults. MRI has a high PPV for diagnosing the type of tear in discoid lateral meniscus for horizontal tears in children and adults and for complex tears in adults.

Short-term clinical outcomes of 42 cases of arthroscopic meniscectomy for discoid lateral meniscus tears

Discoid lateral meniscus of the knee causes a high morbidity in China. Since the traditional treatment to open the capsule and resect the meniscus often results in arthritis, it is now believed that a discoid lateral meniscus should be treated with arthroscopy to preserve part of the meniscus. The current study aimed to investigate the short-term clinical outcomes of arthroscopic meniscectomy for the treatment of discoid lateral meniscus tears. In the present study, we diagnosed and treated 42 patients (47 knees) with discoid lateral meniscus tears using arthroscopy between February, 2007 and December, 2010. Thirty-seven knees received partial resection of the discoid meniscus, 8 received hypo-complete resection and 2 received complete resection. Thirty-nine of the patients were followed up for a mean of 21 months (ranging from 9 to 53 months). The Lysholm scoring system was used to assess the knee function prior to surgery and during the follow-up. The results were analyzed using a Student’s t-test with SPSS 12.0. Our study showed that patients with treated knees returned to normal activities within 4–6 weeks, and knee functions were more improved at 9 months after operation than 3 months, as measured by the Lysholm score (P<0.05). Arthroscopic meniscectomy is an effective treatment for discoid menisci resulting in minimal invasion, quick recovery and early functional exercise. The use of arthroscopy during surgery aids to preserve the meniscus and to reduce stress, therefore, having a beneficial effect on short-term clinical outcomes.

Incidence of Bilateral Discoid Lateral Meniscus in An Asian Population: An Arthroscopic Assessment of Contralateral Knees

To investigate the incidence of bilateral discoid lateral meniscus (DLM) and to evaluate the arthroscopic features of lateral meniscus in asymptomatic contralateral knees in an Asian population who presented with symptomatic DLMs. This study prospectively enrolled 52 consecutive patients who underwent arthroscopic procedures for symptomatic DLMs (31 complete and 21 incomplete) and who consented to the examination of the contralateral knee at the time of arthroscopy. Types of DLMs and of meniscus tears were assessed by use of arthroscopic findings. Preoperative and postoperative functional outcomes were evaluated with Lysholm and Tegner activity scores. Arthroscopic examinations showed 21 complete DLMs, 19 incomplete DLMs, 11 normal lateral menisci, and 1 ring-shaped lateral meniscus in contralateral knees. The incidence of bilateral DLM in our study population was 79% (41 of 52 contralateral knees). Furthermore, 65% of patients (34 pairs of knees) had the same DLM types. In addition, 3 pairs of knees with complete DLMs had menisci of different thicknesses. DLM tears were observed in 2 contralateral knees (1 radial and 1 longitudinal) and were treated by partial central meniscectomy. This study provides evidence of the high prevalence of bilateral DLM in an Asian population.