Evaluation and Treatment of Knee Pain: A Review.

Importance: Approximately 5% of all primary care visits in adults are related to knee pain. Osteoarthritis (OA), patellofemoral pain, and meniscal tears are among the most common causes of knee pain. Observations: Knee OA, affecting an estimated 654 million people worldwide, is the most likely diagnosis of knee pain in patients aged 45 years or older who present with activity-related knee joint pain with no or less than 30 minutes of morning stiffness (95% sensitivity; 69% specificity). Patellofemoral pain typically affects people younger than 40 years who are physically active and has a lifetime prevalence of approximately 25%. The presence of anterior knee pain during a squat is approximately 91% sensitive and 50% specific for patellofemoral pain. Meniscal tears affect an estimated 12% of the adult population and can occur following acute trauma (eg, twisting injury) in people younger than 40 years. Alternatively, a meniscal tear may be a degenerative condition present in patients with knee OA who are aged 40 years or older. The McMurray test, consisting of concurrent knee rotation (internal or external to test lateral or medial meniscus, respectively) and extension (61% sensitivity; 84% specificity), and joint line tenderness (83% sensitivity; 83% specificity) assist diagnosis of meniscal tears. Radiographic imaging of all patients with possible knee OA is not recommended. First-line management of OA comprises exercise therapy, weight loss (if overweight), education, and self-management programs to empower patients to better manage their condition. Surgical referral for knee joint replacement can be considered for patients with end-stage OA (ie, no or minimal joint space with inability to cope with pain) after using all appropriate conservative options. For patellofemoral pain, hip and knee strengthening exercises in combination with foot orthoses or patellar taping are recommended, with no indication for surgery. Conservative management (exercise therapy for 4-6 weeks) is also appropriate for most meniscal tears. For severe traumatic (eg, bucket-handle) tears, consisting of displaced meniscal tissue, surgery is likely required. For degenerative meniscal tears, exercise therapy is first-line treatment; surgery is not indicated even in the presence of mechanical symptoms (eg, locking, catching). Conclusions and Relevance: Knee OA, patellofemoral pain, and meniscal tears are common causes of knee pain, can be diagnosed clinically, and can be associated with significant disability. First-line treatment for each condition consists of conservative management, with a focus on exercise, education, and self-management.

The Relationship Between the Timing of Knee Osteoarthritis Diagnoses and Arthroscopic Partial Meniscectomy.

BACKGROUND: There is ongoing debate regarding the efficacy of arthroscopic partial meniscectomy (APM) for meniscus tears in patients with knee osteoarthritis (OA). Some insurance payers will not authorize APM in patients with knee OA. The purpose of this study was to assess the timing of knee OA diagnoses in patients undergoing APM. METHODS: A large commercial national claims data set containing deidentified information from October 2016 to December 2020 was used to identify patients undergoing arthroscopic partial meniscectomy. Data were analyzed to determine whether patients in this group had a diagnosis of knee OA within 12 months before surgery and for the presence of a new diagnosis of knee OA at 3, 6, and 12 months after APM. RESULTS: Five lakhs thousand nine hundred twenty-two patients with a mean age of 54.0 ± 8.52 years, with the majority female (52.0%), were included. A total of 197,871 patients underwent APM without a diagnosis of knee OA at the time of the procedure. Of these patients, 109,427 (55.3%) had a previous diagnosis of knee OA within 12 months preceding surgery, and 24,536 (12.4%), 15,596 (7.9%), and 13,301 (6.7%) patients were diagnosed with knee OA at 3, 6, and 12 months after surgery, respectively. CONCLUSION: Despite evidence against APM in patients with knee OA, more than half of the patients (55.3%) had a previous diagnosis of OA within 12 months of surgery and 27.0% received a new diagnosis of knee OA within one year of surgery. A notable number of patients had a diagnosis of knee OA either before or shortly after APM.

Low reoperation rate following lateral meniscus root repair: clinical outcomes at 2 years follow-up.

PURPOSE: The aim of this study was to review the outcomes of lateral meniscus posterior root tears repair at the time of ACL reconstruction at a minimum 2-year follow-up. METHODS: Between March 2015 and August 2018, 2017 patients underwent primary ACL reconstruction and were considered for study eligibility. Lateral meniscus posterior root tears were identified arthroscopically, and repair was performed with a transtibial pull-out suture technique or a side-to-side suture technique. Clinical outcomes were recorded at the time of physical examination. At the end of the study period, patients were contacted to determine whether they had required reoperation. RESULTS: Lateral meniscus posterior root tears were identified in 153 out of the 2,017 primary ACL reconstructions (7.6%). Ninety-nine patients were included for analysis: 23 transtibial pull-out sutures and 76 side-to-side repairs. At a mean follow-up of 42 ± 10 months, one patient (1%) had undergone reoperation for failure of the side-to-side repair. There were 11 reoperations in 10 patients (10.1%), including 6 cyclops syndrome, 1 graft rupture, 1 tibial bone cyst, 1 medial and 1 lateral meniscus repair failure, and 1 arthrolysis. Postoperatively, ninety (90.9%) patients were graded A for the IKDC objective score and 9 (9.1%) patients were graded B, with an IKDC subjective score of 86.9 ± 7.6, a Lysholm score of 90.7 ± 6.7 and a median Tegner Activity Scale of 6 (3-9). All of their objective and subjective evaluations improved after surgery (p < 0.001) except for the Tegner Activity Scale. Ten patients underwent second look arthroscopy (10.1%), lateral meniscus healing was observed in 9 out of 10 patients (90%). CONCLUSION: This study demonstrated that lateral meniscus posterior root tear repair is a safe procedure with a very low reoperation rate at a minimum follow-up of 2 years. LEVEL OF EVIDENCE: IV.

Smoking Has No Influence on Outcomes after Repair of the Medial Meniscus in the Hypo and Avascular Zones-A Pilot Study.

Complete loss of the meniscus inevitably leads to knee joint degeneration. Smoking is an important factor predicting poor outcome in orthopedics; however, data about its role in meniscus surgery are inconclusive. Smoking could be an important negative factor in isolated meniscus repair. The aim of this paper was to determine the influence of smoking on functional outcomes after isolated all-inside medial meniscus repair. This study included 50 consecutive patients with isolated, traumatic tear of the medial meniscus who underwent knee joint arthroscopy between 2016 and 2019. All-inside arthroscopic repair of the medial meniscus was performed in each case. All patients followed a uniform, postoperative rehabilitation protocol for 8 weeks. The follow-up examination was based on the functional scores at 3 and 6 months postoperatively. According to smoking status there were 17 smokers and 33 non-smokers. The mean number of cigarettes smoked per day was 11, for a mean of 7.4 years, and the mean pack-years index value was 4.9. There was no correlation between smoking years, number of cigarettes smoked per day, pack-years index, and functional outcomes. The arthroscopic inspection of the knee joints revealed cartilage lesions (≤IIº) in eight subjects, suggesting the secondary pathology to the meniscus tear. In this study, we found no evidence of an association between smoking indices and functional outcomes after all-inside repair of chronic medial meniscus tear. The nature of the chronic meniscal tear could be smoking-resistant owing to the poor blood supply to the sites in which these specific lesions occur.

Declining trends in arthroscopic meniscus surgery and other arthroscopic knee procedures in Denmark: a nationwide register-based study.

BACKGROUND AND PURPOSE: A doubling of arthroscopic meniscal procedures was observed in Denmark from 2000 to 2011, but arthroscopic meniscal procedures for degenerative meniscal tears are no longer recommended. We performed an updated investigation of Danish meniscal procedure trends in the private and public healthcare sectors in Denmark from 2006 to 2018, including trends for other arthroscopic knee procedures. PATIENTS AND METHODS: We extracted data on the 5 most commonly registered arthroscopic knee procedures (diagnostic arthroscopy, meniscal surgery, anterior cruciate ligament reconstruction, synovectomy, and cartilage resection) from the Danish National Patient Register from January 1, 2006 to December 31, 2018, linked with the Danish Population Statistic Register, to obtain data on age and sex. RESULTS: 414,253 arthroscopic knee procedures were registered during 315,290 surgeries on 244,113 individual patients in the study period. For meniscal procedures, the highest incidence was observed in 2010 (319 per 105 persons/year, 95% CI 314-323) and the lowest in 2018 (173 per 105 persons/year, CI 169-176), corresponding to relative decrease of 46% from 2010 to 2018. Remaining arthroscopic procedures also showed declining trends, with lowest incidence for all procedures in 2018. INTERPRETATION: A large decrease in the incidence for arthroscopic meniscal procedures was observed from 2010 to 2018, possibly in response to mounting evidence of limited benefit of this procedure for degenerative knee disease. All other investigated arthroscopic knee procedures also declined in the same period.

Return to sport rate following sports trauma-related delayed bucket-handle meniscus repair with concomitant ACL reconstruction.

BACKGROUND: Return to sports rate of chronic meniscus repair concurrent with Anterior Cruciate Ligament (ACL) reconstruction remains unclear, especially there is no well-defined return to sports criteria for evaluation. The purpose of this retrospective study was to determine the success rate of chronic locked bucket-handle meniscal tear (BHMT) repair with concomitant ACL reconstruction. METHODS: This study includes 51 chronic ACL injury patients with a locked meniscal tear of at least 6 weeks who underwent surgery. All cases were treated with arthroscopic BHMT repair and ACL reconstruction between 2017 and 2020. Patient demograph-ics, chronicity, pre-operative, and intraoperative surgical variables which associated with return to sports were defined. BHMT was repaired with an all-in-side meniscus repair and/or combined repair procedure first, then an anatomic outside-in ACL reconstruction using a suspension device for femoral fixation was performed. Patients underwent same rehabilitation program with the goal of return-ing to sport at approximately 4-8 months. A modified return-to-sport criterion was performed in this study. RESULTS: Fifty-one patients with an average age of 27.4 (range 18-48) years were included in the study. The average time elapsed from the occurrence of locked knee symptoms to surgery was 10.5±4.4 weeks. The mean follow-up time was 25.3±4.5 months. Sig-nificant improvement was observed in all patient-reported outcomes from baseline to the final follow-up. The mean modified Lysholm knee score increased from 45.5 points to 91.5 at the final follow-up (p<0.001). The 43 out of 51 patients (84.3%) were return to their recreational activities (amateur sports). The mean time to return to sport was 5.9±0.8 (5-8) months. CONCLUSION: Majority of the patients who underwent ACL reconstruction with BHMT repair return to their pre-operative activity levels in 8 months. All neglected BHMTs with concomitant chronic ACL rupture should be repaired in a single-stage surgery if the half plane-concave shape of the menisci has been preserved regardless of the delay in time to surgery.

[The postoperative knee : Common complications and their correct diagnosis]. / Postoperative Bildgebung des Kniegelenks : Häufige Komplikationen und deren korrekte Beurteilung.

BACKGROUND: Injuries of the knee are common, with torn meniscus and anterior cruciate ligament tears being among the pathologies most commonly treated by surgery. OBJECTIVES: To review the various normal and pathological postoperative magnetic resonance imaging (MRI) findings following anterior cruciate ligament reconstruction or meniscus surgery. MATERIALS AND METHODS: Evaluation of clinical trials and expert opinions. RESULTS: After knee surgery, various complications (e.g., inadequate tunnel placement, impingement, arthrofibrosis, graft disruption, and recurrent meniscus tear) have been described. These can usually be reliably diagnosed if the timing and type of surgery are known; however, limitations for imaging must also be considered. CONCLUSIONS: Interpretation of postoperative knee MRI is challenging and requires knowledge of common complications of each type of surgery and their normal postoperative appearance on MRI.

Isolated meniscus injuries in skeletally immature children and adolescents: state of the art.

The prevalence of isolated meniscal injuries in children and adolescents is low; however, we see an increase mainly due to intensified sports-related activities at an early age. A meniscal repair should be attempted whenever possible as children present with increased meniscal healing potential. The diagnosis and management of meniscal tears involve both patient factors and tear characteristics: size, anatomical location and associated injuries. Special attention should be given to the feature of discoid menisci and related tears as they require a specific management plan. This state-of-the-art review highlights the most recent studies on clinical evaluation, surgical techniques, tips and tricks, pitfalls, outcomes, return-to-sports, geographical differences and future perspectives related to meniscal injuries in children and adolescents.

The impact of body mass index on the accuracy of the physical examination of the knee.

PURPOSE: Obesity is a worldwide pandemic; however, no adaptations were made to the physical examination of obese patient's knees. The accuracy of the physical examination is critical for correct assessment and selection of treatment. We aimed to assess whether body mass index (BMI) affects the sensitivity and specificity of common provocative knee tests. METHODS: We studied 210 patients who underwent knee arthroscopy to treat anterior cruciate ligament (ACL) and meniscal pathologies. BMI and the knee's physical examination were documented pre-operatively. Sensitivity, specificity, and accuracy of ACL and meniscal provocative tests in relation to BMI were evaluated using arthroscopy as a gold standard. RESULTS: The Anterior Drawer, Lachman, and Pivot-Shift tests for ACL tears were significantly less accurate and sensitive, yet more specific, in obese patients when compared to normal and overweight patients. The McMurray, Apley Grind, and Thessaly tests for medial meniscus tears showed greater sensitivity, but lower specificity, in patients with increased BMI. Above normal BMIs, independently of age and gender, were significantly associated with higher odds for positive ACL tests. CONCLUSION: Tests for ACL tears are less sensitive in obese patients and alternatives to the classic tests should be considered. Medial meniscus tests tend to be more sensitive and less specific in patients with greater BMIs. Their results should be carefully interpreted due to possible false positives. The physician should take into consideration the impact of patient BMI on the accuracy of their physical examination of the knee to optimize treatment decision-making.

The aspiration test reveals an instability of the posterior horn of the lateral meniscus in almost one-third of ACL-injured patients.

PURPOSE: Anterior cruciate ligament (ACL) injuries often lead to associated injuries of the posterior horn of the lateral meniscus (PHLM). Arthroscopic, assessment of PHLM instability may be difficult in the absence of a visible meniscus damage. The main objective of this prospective multi-center study was to compare the ability of the probing and aspiration tests to identify PHLM instability in a population of patients undergoing ACL reconstruction (ACLR) and a control group of patients with an intact ACL undergoing knee arthroscopy. METHODS: A prospective case-control analysis was performed in three sports medicine centers. One-hundred and three consecutive patients operated for a primary isolated ACLR without structural lateral meniscus damage other than a root tear were included. They were compared to a control group of 29 consecutive patients who had a knee arthroscopy with an intact ACL and no structural lateral meniscus lesion. The probing and aspiration tests were consecutively executed according to previously published methods. RESULTS: In the control group, no lateral meniscus lesions were visualized during arthroscopy, and both probing and aspiration tests were negative in all patients. In the group of ACL-injured patients, a Forkel type I-III posterolateral meniscus root tear (PLMRT) was found in 12 patients (12%). In this subgroup, the probing test was positive in 4/12 patients (33%) and the aspiration test in 5 additional patients (75%). In 15 patients (15%), an elongation of the posterior root of the lateral meniscus (defined as type IV PLMRT as an addendum to the Forkel classification) could be observed during arthroscopy. In this subgroup, only 1 patient displayed a PHLM instability with the probing test (7%), whereas the aspiration test was positive in 13/15 patients (87%). In the remaining 76 patients (74%), no structural lesion of the PHLM could be identified. Nevertheless, an instability of the PHLM could be identified in 8 of them (11%) with the probing test, and the aspiration test was positive in 2 additional knees (13%) of this apparently normal subgroup. Altogether, in the entire ACL injury cohort, a positive probing test was observed in 13/103 patients (13%) and a positive aspiration test in 32/103 knees (31%) (p < 0.01). CONCLUSION: Careful observation and examination of the PHLM with the aspiration test revealed a substantial amount of previously undiagnosed lateral meniscus instabilities in ACL-injured knees. The prevalence of PHLM instability as evaluated by the aspiration test was high (31%). The aspiration test was superior to the probing test in detecting an instability of the PHLM in a population of ACL-injured patients. LEVEL OF EVIDENCE: II.

Evidence-based rationale for treatment of meniscal lesions in athletes.

Meniscal injuries in elite athletes are a common cause of missed game time and even have the potential to be career shortening. In this patient group, care must be paid not only to the pathology, but also to a player's contract status, time in the season, specific demands of his/her sport and position on the field, and future consequences. Successful treatment requires the clinician to understand the player's goals and needs, communicate effectively between all stakeholders, and a have knowledge of the challenges posed by the different types of meniscal tear seen in this population. Paramount is the distinction between injuries to the medial and lateral meniscus. Deficiency of the lateral meniscus, as a result of a tear or a meniscectomy, leads to frequent early problems and inexorably to chondral degeneration thereby affecting an athlete's ability to perform. Therefore, it is strongly recommended to repair the majority of lateral meniscal tears. Medial meniscal tears pose a more challenging treatment dilemma, as the success of partial meniscectomy in achieving reproducible, early return to play must be balanced against the long-term degenerative consequences. Many meniscal tears are correctly treated non-operatively.Level of evidence V.

Mechanical symptoms and meniscal tear: a reappraisal.

OBJECTIVE: To identify and summarize literature related to the association between mechanical symptoms (catching and locking of the knee), the presence of meniscal tear, and outcomes after arthroscopic surgery. DESIGN: We searched PubMed and hand-searched reference lists for relevant articles and selected 38 for analysis. RESULTS: Mechanical symptoms appear to have modest sensitivity (ranging 0.32-0.69), specificity (ranging 0.45-0.74) and positive predictive value (ranging 0.75-0.81) for meniscal tear. There is also very little evidence to suggest that those with mechanical symptoms experience better outcomes after arthroscopic surgery. CONCLUSION: Our examination of the literature does not support the hypothesis that mechanical symptoms are related to the presence of meniscal tear or portend better outcomes after arthroscopic surgery.

Meniscus Anatomy and Basic Science.

A basic understanding of meniscal anatomy and biomechanics is important for physicians evaluating knee injuries and surgeons treating meniscal injuries. This chapter provides a concise review of meniscal anatomy and biomechanics relevant for the evaluation and treatment of meniscus injuries. Anatomic landmarks relevant for meniscal root repair and transplant are discussed, along with the gross, microscopic, vascular, and neuroanatomy of the menisci.

Meniscal Allograft Transplantation.

Meniscal allograft transplantation provides treatment options for patients with a meniscus-deficient knee with lifestyle-limiting symptoms in the absence of advanced degenerative changes. Meniscal transplantation helps to restore the native biomechanics of the involved knee, which may provide chondroprotective effects and restoring additional knee stability. Improvements in pain, function, and activity level have been seen in appropriately selected patients undergoing transplantation. Although various surgical implantation options exist, the majority focus on reproducing native attachments of the meniscal roots to allow near normal mechanics. Although meniscal transplantation may serve as a salvage procedure for symptomatic patients with a meniscus-deficient knee, it may prevent or delay the necessity of a more invasive arthroplasty procedure.

[Classification and treatment of modern traumatic meniscal tears]. / Classification et traitement modernes des déchirures méniscales traumatiques.

The menisci have several important biomechanical functions. Traumatic meniscal injuries present a wide spectrum of presentation and several types of lesions. They can concern the body of the meniscus and its fixation. An easy and clear classification of traumatic meniscus tears is essential for helping the physicians to achieve the correct surgical indication and the accurate postoperative rehabilitation protocol. The aim of this current concept review is to clearly describe some classical as well new type of meniscal and menisco-synovial lesions such as ramp lesions, root tears and instability of the lateral meniscus associated to rotational laxity. The goal is to focus on the definition, diagnosis, classification, giving some guidelines and discussing the different rehabilitation protocols.

Les ménisques sont essentiels au fonctionnement biomécanique du genou. Les lésions méniscales traumatiques peuvent se manifester par des tableaux cliniques très variés et concerner le corps du ménisque, ses attaches à l'os ou à la capsule articulaire. Une classification simple et claire des déchirures méniscales traumatiques est indispensable. Cette revue de la littérature contemporaine fait un tableau précis des lésions méniscales traumatiques classiques et « nouvelles ¼ telles que celles de la rampe, les avulsions de la racine méniscale et l'instabilité du ménisque externe associée à une laxité rotatoire du genou, en se focalisant sur la définition de chacune de ces déchirures, leur diagnostic, leur classification, afin de proposer des directives de traitement et de rééducation.

The efficacy of meniscus posterior root tears repair: A systematic review and meta-analysis.

PURPOSE: To report of efficacy repair treatment for meniscus posterior root tears repair. METHODS: We systematically searched databases including PubMed, Embase, and Cochrane Library for relevant articles. Coleman Methodology Score was used for a quality assessment of the included studies. A meta-analysis was performed to analyze for efficacy of MMPRTs repair. RESULTS: Twenty-two studies, 14 level III and 8 level IV, were included in this systematic review, with a total of 926 cases. Studies comparing repair with either meniscectomy or conservative treatment found greater improvement and slower progression of Kellgrene-Lawrence grade with meniscal repair. Decreased meniscus extrusion is beneficial to the prognosis of patients undergoing MMPRTs repair. As treatment efficacy, the Lysholm score increased 28.87 (P < 0.001), IKDC score increased 31.73. The overall pooled event rates of progression of K-L grade is 0.200. Difference of Lysholm score and IKDC score between repair and meniscectomy were 8.72 and 9.67. CONCLUSIONS: The clinical subjective score after MMPRT repair was significantly improved compared with the preoperative status. Considering the progression of joint K-L grade, it can prevent the progression of arthrosis to some extent, but not completely. Decreased meniscus extrusion is beneficial to the prognosis of patients undergoing MMPRTs repair. Based on these results, MMPRTs repair cloud result favorable outcomes.

Diagnosis and Management of Articular Cartilage and Meniscus Pathology in the Posterior Cruciate Ligament-Injured Knee.

Posterior cruciate ligament (PCL) injuries commonly occur in association with participation in sporting or recreational activities or due to a direct trauma. Cartilage and meniscal lesions are prevalent in PCL-injured knees with increasing likelihood and severity based on extent and duration of trauma to the knee. As such, comprehensive diagnostics should be performed to ascertain all related pathology, and patients should be thoroughly educated regarding treatment options, likely sequelae including posttraumatic osteoarthritis, and associated outcomes. Treatments should address the joint as an organ, ensuring stability, alignment, and functional tissue restoration are optimized by the most efficient and effective means possible. Compliance with patient- and procedure-specific postoperative management protocols is critical for optimizing successful outcomes for these complex cases. The objectives of this review article are to highlight the likelihood and importance of osteochondral and meniscal pathology in the PCL-injured knee, and to provide the best current evidence regarding comprehensive evaluation and management for PCL-injured knees with cartilage and/or meniscal comorbidities.

Arthroscopically assisted evaluation of frequency and patterns of meniscal tears in operative tibial plateau fractures: a retrospective study.

BACKGROUND: Despite tibial plateau fractures are often associated with meniscal tears, the association between meniscal tears and Schatzker classification remains unclear. The purpose of this study was to assess the frequency and patterns of meniscal tears in operatively treated tibial plateau fractures following immediate arthroscopic evaluation after internal fixation of tibial plateau fractures and to reveal the association between these concomitant meniscal tears and Schatzker classification. METHODS: A total of 252 consecutive patients (166 males and 86 females, mean age 46.7 (19-80) years) with operatively treated tibial plateau fractures admitted to our hospital from January 2016 to May 2019 were performed. Arthroscopic examination for frequency and patterns of meniscal tears was evaluated and documented at the time of surgery, and the association between the frequency and patterns of meniscal tears with Schatzker classification was then analyzed. RESULTS: The overall frequency of meniscal tears in TPFs was 67% (168 of 252) with 33% (84 of 252) of these being lateral meniscal tears, and 10% (26 of 252) medial meniscal tears, while 23% (58 of 252) had bilateral meniscal tears. Schatzker II was most commonly associated with meniscal tears, occurring in 72% (71 of 99) of our series. There is no significant difference between the frequency of meniscal tears and Schatzker classification (p > 0.05). The most common patterns of meniscal tears were longitudinal tears in 23% of tibial plateau fractures (59 of 252), and it occurred at a significantly higher frequency in Schatzker II with 43% (43 of 99). Schatzker IV had significantly higher prevalence of bucket-handle tears than other fracture patterns (p < 0.05), and Schatzker VI fractures had significantly higher prevalence of complex tears than other fracture patterns (p < 0.05). For other Schatzker classification, the patterns of meniscal tears demonstrated no statistical difference (p > 0.05). CONCLUSION: The results identified that meniscal tears are commonly seen in each Schatzker classification. Although various patterns of meniscal tears occurred in tibial plateau fractures, the most common patterns were longitudinal tears. Importantly, we suggest that the status of meniscal tears associated with TPFs should be considered at the time of surgery in addition to fracture fixation.

Preoperative morphologic changes of the medial meniscus correlate with suture translations during knee flexion in pullout repair of medial meniscus posterior root tear.

BACKGROUND: Medial meniscus (MM) translates and extrudes posteriorly during knee flexion in MM posterior root tear (MMPRT) knees, and transtibial pullout repair of MMPRT has been performed to regulate the MM extrusion. This study aimed to calculate each suture translation during knee flexion in transtibial pullout repair of MMPRT, and to investigate the morphologic features of the MM that lead to longer suture translations during knee flexion. METHODS: Thirty patients with MMPRT who met the operative indication of pullout repair were enrolled and investigated prospectively. Pullout repair was performed by using two simple stitches (outer and inner sutures) and an all-inside suture in the posteromedial part of the MM. Each suture's translation from 0° to 90° of knee flexion was measured intraoperatively. The MM morphologic features, including MM medial extrusion (MMME) and MM posterior height (MMPH), were measured using preoperative magnetic resonance imaging, and the correlation between these values and each suture translation was evaluated. RESULTS: The average outer, inner, and all-inside suture translations were 4.8 mm, 3.9 mm, and 1.3 mm, respectively. Significant correlations were observed between the outer suture translation and MMME, and MMPH (p < 0.001 and <0.01, respectively). The thresholds for preoperative MMME and MMPH for longer outer suture translations (≥6 mm) were 2.1 mm and 5.4 mm, respectively. CONCLUSIONS: Preoperative longer MMME and higher MMPH were associated with longer meniscus translations during knee flexion during MMPRT repair.

Is there a good agreement between MRI readers for Thaunat's classification in arthroscopically-proven meniscal ramp lesions?

OBJECTIVE: To describe and evaluate the reproducibility by MRI of an arthroscopically-based classification for meniscal ramp lesions. We hypothesize that MRI would present good interobserver and intraobserver reliability to evaluate meniscal ramp lesions. MATERIALS AND METHODS: Twenty MRI of the knee with arthroscopically-proven meniscal ramp lesions were independently assessed by two skilled musculoskeletal radiologists and a third-year radiology resident. Reading was performed in a randomized and anonymous manner, in two steps, with a minimum of 1-month interval between each. Cohen's kappa coefficient statistic was used to analyze intra and interobserver reading agreement. Associate findings were also categorized. RESULTS: From 20 subjects, 17 were male, with mean age of 35 years. MRI reading showed type IV ramp lesion as most prevalent with eight cases (37%), followed by type V - four (21%), type I - four (20%), type III - three, (16%) and type II - one (6%). Regarding ramp lesion types, intraobserver agreement was substantial for both skilled readers (Kappa = 0.72), and moderate for the less experienced reader (Kappa = 0.51); interobserver agreement was moderate. Results between most experienced readers were also analyzed in two categories: stable (types I and II) and unstable (types III, IV and V), also resulting in moderate agreement (Kappa = 0.54). Intraobserver agreement was substantial for both readers (Kappa = 0.68). The most common associate findings were joint effusion (85%), posteromedial capsular structures injury (60%), and medial meniscus extrusion (60%). CONCLUSION: The arthroscopy classification for meniscal ramp lesions stability adapted for MRI has good reproducibility when applied by trained musculoskeletal radiologists.