Type Of Meniscal Lesion Research Articles

Ramp lesions : Tips and tricks in diagnostics and therapy

There is an increasing biomechanical and anatomical understanding of the different types of meniscal lesions. Lesions of the posterior part of the medial meniscus in the meniscosynovial area have recently received increased attention. They generally occur in association with anterior cruciate ligament (ACL) injuries. They are often missed ("hidden lesions") due to the fact that they cannot be seen by routine anterior arthroscopic inspection. Furthermore, meniscosynovial lesions play arole in anteroposterior knee laxity and, as such, they may be acause of failure of ACL reconstruction or of postoperative persistent laxity. Little information is available regarding their cause with respect to injury mechanism, natural history, biomechanical implications, healing potential and treatment options. This article presents an overview of the currently available knowledge of these ramp lesions, their possible pathomechanism, classification, biomechanical relevance as well as repair techniques.

Association among meniscal tear morphology, meniscal symptoms and knee pain severity

Purpose: Meniscal tears are present in a large percentage of patients with knee osteoarthritis (OA). It remains controversial whether all meniscal tears contribute similarly to knee symptoms and pain in patients with OA. We sought to examine the relationship between meniscal tear morphology documented onMRI and reported symptoms in patients with OA. We hypothesized that simple (e.g. vertical, radial) tears are associated with mechanical symptoms due to interference of meniscuswith smooth jointmotion,while complex andhorizontal tears, maceration, and root tears are associatedwith greater kneepain severity. Methods: We used baseline data from subjects enrolled in the Meniscal Tear in Osteoarthritis Research (MeTeOR) randomized clinical trial. Recruitedmales and females were 45 years or older and hadmeniscal tear onMRI, evidence of OAon radiographs orMRI, and at least 4weeks of knee pain and characteristicmeniscal symptoms.MRIs were read using theMRI OA Knee Score (MOAKS). Meniscal tears from both medial and lateral menisci were categorized in a hierarchical manner as follows: root tears; maceration (partial or complete, in any compartment); complex or horizontal tears. (This categorywas further stratified into longer tears spanning 2 or 3 subregions: anterior, posterior, body, and shorter tears only visualized in 1 subregion.) The final category in the hierarchy was simple tears, comprised of vertical and radial tears. Mechanical meniscal symptoms included clicking, catching and popping. Frequency of meniscal symptoms over the last week was scored 3-15, with 15 being most frequent. Pain severity was assessed using theWestern OntarioM andb)pain severity – after adjusting for age, sex, body mass index (BMI), KellgrenLawrence (KL) radiographic grade, MOAKS-based evidence of mensical extrusion, bone marrow lesions (BMLs, size and number), and Hoffa-synovitis. We also examined root tears as a binary predictor of WOMAC pain. Results: The sample consisted of 227 knees (one per person) with completeMRI and survey data. Root tearswere seen in 19%,maceration in 14%, long complexor horizontal tears in 22%, short complexor horizontal tears in 30%, and simple tears in 14% of subjects. We found neither statistically significant nor clinically important associations between meniscal tear morphology and frequency of meniscal symptoms. Root tears were associatedwith higher (worse)WOMAC pain scores than any of the other morphologies. We did not observe an association between pain severity and the BML indicators, meniscal extrusion, or Hoffa-synovitis and therefore did not include these covariates in the final model. The final models were adjusted for age, sex, BMI and KL grade because of these variables’ clinical relevance. The final models did not demonstrate associations between the tear morphologies and meniscal symptoms (Table 1). Root tear was assoiated with greater overall pain (Table 1). Further analysis with root tear as a binary predictor of WOMAC pain yielded an adjusted mean WOMAC Pain score of 45 for those with root tear and 39 without root tear (p1⁄40.03) afteradjustment forage, sex, BMIandKLgrade. Conclusions: We did not find evidence of a relationship between meniscal tear morphology and characteristic meniscal symptoms. Root tears were associated with greater knee pain than other types of meniscal lesions, even with adjustment for other demographic and imaging factors. These findings indicate that pain severity varies depending on the morphology of meniscal tear. Further studies examining the outcomes of surgical and conservativemanagement of patients with meniscal tears should take tear morphology into consideration.

Clinical and radiographic results of arthroscopic partial lateral meniscectomies in stable knees with a minimum follow up of 20 years.

The purpose of this retrospective multicentric study was to evaluate the long-term effects of lateral meniscectomy and to identify those patients who are at the most risk of developing osteoarthritis (OA). Eighty-nine arthroscopic partial lateral meniscectomies in stable knees with a mean follow-up of 22 ± 3 years were included. The following influencing factors were analyzed: age, sex, body mass index (BMI), physical activity, alignment, the types of meniscal lesions, the extent of meniscal resections and the initially associated cartilage lesions. An independent examiner reviewed all patients, using subjective (KOOS and IKDC scores) and objective clinical and radiological evaluations (IKDC score). The contralateral knee was used as a reference to calculate the prevalence and the incidence of OA. The mean age at the time of surgery was 35 ± 13 years. The main location of the lesions was the mid-section of the lateral meniscus (79% of the cases). At the latest follow-up, 48% of the patients had an active lifestyle with as many as 48% of the patients enjoying moderate to intense physical activity 22 years after the procedure (vs. 71% before surgery). The KOOS score evolved from 82 to 69% during the same period. The prevalence of OA was 56% in the affected knee and the difference of prevalence between the operated and healthy knees was 44%. In those patients presenting with an OA of the operated knee and a normal contralateral knee, the incidence of OA was 53%. Predictors of OA were an age superior to 38 years at the time of surgery, obesity (BMI >30), and valgus malalignment as well as the presence of cartilage and degenerative meniscal lesions at the time of surgery. In the long term, arthroscopic partial lateral meniscectomy in stable knees without initial cartilage lesions might yield good to excellent results in young patients. Patients are at higher risk to develop symptomatic OA if they are over 40, having a high BMI, valgus malalignment and cartilage lesions at the time of surgery. This study provides precise guidelines for the surgical treatment of lateral meniscus tears. IV.

Updates in biological therapies for knee injuries: menisci.

The preservation of meniscal tissue is paramount for long-term joint function, especially in younger patients who are athletically active. Many studies have reported encouraging results following the repair of meniscus tears, including both simple longitudinal tears located in the periphery and complex multiplanar tears that extend into the central third avascular region. However, most types of meniscal lesions are managed with a partial meniscectomy. Options to restore the meniscus range from an allograft transplantation to the use of synthetic and biological technologies. Recent studies have demonstrated good long-term outcomes with meniscal allograft transplantation, although the indications and techniques continue to evolve, and the long-term chondroprotective potential of this approach has yet to be determined. Several synthetic implants, most of which are approved in the European market, have shown some promise for replacing part of or the entire meniscus, including collagen meniscal implants, hydrogels, and polymer scaffolds. Currently, there is no ideal implant generated by means of tissue engineering. However, meniscus tissue engineering is a fast developing field that promises to develop an implant that mimics the histologic and biomechanical properties of a native meniscus.

Contact Mechanics of Simulated Meniscal Tears in Cadaveric Canine Stifles

To evaluate the biomechanical effects of 5 types of meniscal lesions on contact mechanics in the canine stifle. Experimental study. Cadaveric canine stifles (n=12 pair). Medial meniscal lesions (radial, vertical longitudinal, nonreducible bucket handle, flap, and complex tears) were simulated in cadaveric stifles. A contact map was recorded from each tear type and contact area (CA) and peak contact pressure (PCP) from each tear type were compared. A significant difference in PCP was detected between control and nonreducible bucket handle, flap, and complex tears. PCP increased by >45% in nonreducible bucket handle, flap, and complex meniscal tears when compared with control. No significant difference was found in PCP between control and radial and vertical longitudinal tears. No significant difference was found in CA between any of the meniscal conditions. Nonreducible bucket handle, flap, and complex tears cause a significant increase in PCP. Radial and vertical longitudinal tears had a minimal impact on the contact pressures of the medial compartment of the stifle. Based on this ex vivo model, we support the clinical recommendation of debriding nonreducible bucket handle, flap, and complex tears because the injured portion of the meniscus no longer contributes significantly to the function of the meniscus. Radial and vertical longitudinal tears do not cause a change in contact mechanics allowing consideration of nonsurgical treatment and meniscal repair, respectively. Future experimental and clinical studies should aim to refine the treatment of specific meniscal injuries.

Paper #172 Clinical results after arthroscopic meniscectomy for discoid lateral menisci

The clinical results after meniscectomy for the discoid meniscus has been variable especially in the long term follow up. We reviewed the cases of one hundred nineteen knees with symptomatic discoid lateral meniscus who underwent total, subtotal or partial arthroscopic meniscectomy between January 1990 and December 1999. The mean age at surgery was 30.5 years old (range: three to sixty years) at the time of operation. Preoperative duration of symptoms was 16.8 months and average duration of follow up was 60.1 months. At arthroscopy, 91 menisci were complete, 28 menisci were incomplete type. Patients were divided into three groups based on the type of surgery. Arthroscopic total meniscectomy was underwent in 47 cases of knee, subtotal meniscectomy in 21 cases and partial meniscectomy in 51 cases. On the basis of Ikeuchi grading system, 34 knees were graded as excellent, 62 knees were rated as good, 22 knees were rated as fair and 1 knee as poor. Longer duration of symptom and older age had a statistically significant higher risk of developing chondromalacia in knee joint (P = 0.001). But no correlation was found between symptom duration and type of meniscal lesion. In patients who had had total meniscectomy for the complete type of lesion and partial meniscectomy for the incomplete type, results were satisfactory respectively in cases of less than 5 years follow-up. We found unsatisfactory results with significant preoperative chondromalacia and longer follow up. The clinical results after meniscectomy for the discoid meniscus has been variable especially in the long term follow up. We reviewed the cases of one hundred nineteen knees with symptomatic discoid lateral meniscus who underwent total, subtotal or partial arthroscopic meniscectomy between January 1990 and December 1999. The mean age at surgery was 30.5 years old (range: three to sixty years) at the time of operation. Preoperative duration of symptoms was 16.8 months and average duration of follow up was 60.1 months. At arthroscopy, 91 menisci were complete, 28 menisci were incomplete type. Patients were divided into three groups based on the type of surgery. Arthroscopic total meniscectomy was underwent in 47 cases of knee, subtotal meniscectomy in 21 cases and partial meniscectomy in 51 cases. On the basis of Ikeuchi grading system, 34 knees were graded as excellent, 62 knees were rated as good, 22 knees were rated as fair and 1 knee as poor. Longer duration of symptom and older age had a statistically significant higher risk of developing chondromalacia in knee joint (P = 0.001). But no correlation was found between symptom duration and type of meniscal lesion. In patients who had had total meniscectomy for the complete type of lesion and partial meniscectomy for the incomplete type, results were satisfactory respectively in cases of less than 5 years follow-up. We found unsatisfactory results with significant preoperative chondromalacia and longer follow up.

MR imaging of Baker cysts --prevalence and relation to internal derangements of the knee.

To evaluate the prevalence of popliteal cysts in patients studied with magnetic resonance (MR) imaging. Cyst presence and volume will be related to other internal derangement of the knee. Three hundred and eighty-two consecutive patients with a MR study of the knee were included. Images were obtained in the three spatial orthogonal planes and evaluated through consensus. Four categories were established for the Baker cyst and synovial fluid (absence, minimum, moderate and massive), and the presence of meniscal, cruciate ligaments and cartilage lesions were recorded. Statistical analysis was carried out with bivariate analysis (chi(2) of Pearson and Gamma tests). From the 382 patients, 145 had Baker cysts (38.0%). Cyst content was minimum in 99, moderate in 34 and massive in 12. Joint effusion was observed in 269 patients (70.4%), being minimal in 140 patients, moderate in 119 and massive in ten. Meniscal lesions were observed in 195 patients (51%), while 58 patients (15%) had a cruciate ligament lesion. Baker cyst had a statistically significant direct relationship with the presence and quantity of synovial fluid (P=0.002) and with the presence and type of meniscal lesion (P=0.01) but not with cruciate ligaments or cartilage lesions. The prevalence of Baker cysts in MR studies of the knee is high. Its presence and volume are related to the quantity of synovial fluid, and to the presence and severity of meniscal lesions.

Effects of the type of meniscal lesion on knee function

The relationship between the type of meniscal lesion (bucket-handle, flap or degenerative tears) and preoperative knee function (5.1±6.2 days before arthroscopic meniscectomy) was studied in 35 patients. Patients with bucket-handle tears (group B, n=12) had large knee extension work deficits during maximal voluntary contractions at 30° and 180°/s (Kin-Com dynamometer). These work deficits were accompanied by proportional decreases in the prime mover or agonist-EMG levels (VM: vastus medialis and/or VL: vastus lateralis). These patients had smaller deficits during flexion movements at 30°/s. Moreover, a larger number of negative clinical signs and symptoms (pain at rest and during tests, locking, thigh atrophy, extension and flexion movement deficits larger than 10°) were found with an equal or a higher prevalence in group B than in the other groups. Patients with flap tears (group F, n=15) had deficits in work and agonist-EMG activity (VM and VL) only during the extension tests. In contrast, patients with degenerative tears (group D, n=8) had a work deficit and a concomitant decrease in the EMG level of the medial gastrocnemius (MG), only during the flexion test at 30°/s. Comparable mean knee function scores, as measured by the Lysholm and Gillquist questionnaire [35], were obtained for the three groups of patients, suggesting that this measure was not sensitive enough to discern functional differences related to types of meniscal tears. The results of this study have demonstrated a link between the type of meniscal lesion and the consequent preoperative knee joint disability profile as defined by comparison with the sound leg. These results emphasize the need to consider meniscal lesion type and an individual's preoperative strength deficit when group comparisons of patients are made or the effects of therapy (arthroscopic surgery and rehabilitation) are evaluated.

Factors predicting knee function in patients with meniscal lesions

The relationships between the magnitude of strength and muscle activation (EMG activity) deficits during maximal isokinetic knee movements and clinical and anthropometric factors (pain, effusion, type of meniscal lesion, degenerative changes, duration of symptoms and age) were studied in a group of 34 patients 5 days (5.3 ± 6.2 days) before arthroscopic meniscectomy. Moderate correlations were found between deficits in the area under the torque-angle curve (work) and the activation level in the agonist muscles during both the extension and flexion tests at 30° s −1 and 180° s −1 suggesting that the decrease in the isokinetic mechanical output is dependent on the reduced muscle activation. The severity of pain during tests was the best predictive clinical factor for the size of the work and EMG deficits but each of the tollowing factors: the presence of knee effusion and thigh atrophy, the type of meniscal lesion and the age of the patients, also had some predictive value for the magnitude of the deficits. In contrast, the duration of symptoms and the presence of osteo-articular degenerative changes were not related to the preoperative isokinetic knee performance. These results suggest that older patients (especially over 45 yr) with bucket-handle meniscal tears, knee effusion, thigh atrophy and severe pain on exertion, are most likely to have poor preoperative knee isokinetic performance. Since the magnitude of the pre- and postoperative knee deficits are correlated, it is important to identify patients at risk preoperatively so that optimal rehabilitation can be instituted.

Isolated arthroscopic partial meniscectomy. Functional radiographic evaluation at five years.

Fifty patients who underwent isolated arthroscopic partial meniscectomy with a minimum followup of 5 years were analyzed retrospectively. To analyze the factors associated with a satisfactory or an unsatisfactory clinical result, we looked at the patient's age, duration of symptoms, type of meniscal lesion, and articular cartilage abnormalities. The patients were graded with a functional knee score (Lysholm-Gillquist), and activity level before surgery and at followup was determined. The data also included radiographic evaluation of 29 of the 50 patients. Tibiofemoral alignment was measured, and osteoarthritic changes were graded and correlated with the type of meniscal abnormality and functional result. Eighty-two percent of our patients had satisfactory knee function, and the activity level was maintained. The factors associated with a satisfactory result after a partial meniscectomy included age less than 40 years, symptoms less than 12 months duration, type of tear, and chondromalacia less than grade II. Fairbank's changes were present in 50% of the patients, with significant grade III and IV changes identified in 30%. Although the radiographic changes did not necessarily correlate with the functional result, we felt that the changes were significant and indicative of abnormal stress transfer to articular cartilage and bone.

Meniscal tears and associated anterior cruciate ligament tears in athletes: course of treatment.

Sixty-two athletes whose injured knees had negligible instability were found to have an absent or functionless anterior cruciate ligament (ACL) at the time of medial meniscectomy. After a mean of 52 months of followup, 51 patients were examined; 24 (47%) had returned to full sports activities, whereas 27 (53%) acknowledged incidents of the knee "giving way" or having completely given up sports because of instability. By analyzing the following variables, the jerk test, the type of meniscal lesion, and the type of sports engaged, we formulated a rating system to be used intraoperatively for determining the need for combining meniscectomy with a ligament reconstruction.

Comparison of Open and Endoscopic Meniscectomy

Fifty-eight patients who had undergone meniscal surgery were reviewed. Half had undergone conventional open meniscectomy, and half had been treated by arthroscopic meniscectomy. Each patient in the open group was matched with a patient in the endoscopic group by age, sex, and type of meniscal lesion. Patients with ligamentous injuries were excluded. Twelve patients in the endoscopic group were operated on as outpatients; the mean post-operative hospital stay in the 17 hospitalized patients in the endoscopic group was one day as compared with a mean of 3.3 days for the patients in the open group. Sick leave for the endoscopic group was only one-third of that of the open group. Operating time was 74.5 +/- 38.7 minutes in the open group compared with 55.9 +/- 25.0 minutes in the endoscopic group. At follow-up evaluation (mean follow-up period, 38 months) the percutaneous group showed a knee function score (88.7 points) similar to that of the open group (85.3 points) at 51 months. A three-year follow-up study of patients operated on endoscopically for a single meniscal lesion demonstrated that results with endoscopy are as satisfactory as those obtained by conventional surgery. Advantages of endoscopy include decreased hospitalization and shorter sick leave, with a corresponding reduction in the cost of patient care.

Meniscectomy and chondromalacia of the femoral condyle

One hundred and fifty-four knees with 161 torn menisci were examined with the arthroscope immediately before meniscectomy. The incidence of early degenerative arthritis (chondromalacia) of the femoral condyle was correlated with the age of the patient, the interval between injury and surgery, and the type of meniscal lesion. The incidence of condylar chondromalacia was significantly higher in patients over the age of thirty (p less than 0.01) and in those with a history longer than three months (p less than 0.05). Posterior horn tears were associated with the highest incidence of degenerative changes, but were also associated with a longer history and with older patients. Attention is drawn to the adverse effect of damaged menisci on condylar articular cartilage, and a plea is made for early diagnosis and removal of damaged menisci.