Diagnostic value of ultrasound in the discoid lateral meniscus of the knee / 中国骨伤

OBJECTIVE@#Based on the anatomical differences between discoid lateral meniscus(DLM) and normal lateral meniscus (NLM), this study aims to setting up the ultrasound examination parameters to distinguish DLM and NLM and explore the diagnostic value of these parameters on DLM.@*METHODS@#According to the inclusion, exclusion and matching criteria, 66 DLM patients(DLM group) and 132 NLM patients with other knee joint diseases(NLM group), hospitalized from October 2019 to June 2020, were included in this study. There were 18 males and 48 females in the DLM group, ranging in age from 3 to 60 years old, with a mean of (36.9±12.1) years old;36 males and 96 females in the NLM group, ranging in age from 3 to 60 years old, with a mean of (40.0±12.2) years old. Philips high frequency(3.0 to 12.0 MHz) linear array ultrasound probe was used to examine the lateral meniscus of all patients in two groups. Nine parameters including the thickness, width and the included angle of the anterior angle, body and posterior angle respectively in the lateral meniscus were measured. The included angke is formed by the chords of the upper and lower curved surfaces of the meniscus at the free edge. The independent t test was used to analyze the difference of the measured parameters between the DLM group and the NLM group. The receiver operating characteristic(ROC) curve was used to evaluate the cut-off value of each parameter for diagnosing DLM and the corresponding sensitivity, specificity, positive predictive value, negative predictive value, and area under the ROC curve(AUC).@*RESULTS@#The above 9 ultrasound measurement parameters between the DLM group and the NLM group had significant statistical differences(P<0.001). The ROC curve analysis method evaluated the cut-off value and diagnostic capabilities of these nine ultrasound parameters for DLM. The results showed that the cut-off value of the included angle of anterior part, body and posterior part were 25.85°, 24.85° and 29.15 °, respectively;and the sensitivity, specificity, negative predictive value, positive predictive value and AUC were significantly higher than other parameters, which were 88%, 91%, 79%, 95%, 0.94;89%, 94%, 82%, 97%, 0.96; 92%, 97%, 86%, 98%, 0.97, respectively.@*CONCLUSION@#Ultrasound diagnosis of DLM is feasible and reliable. The diagnostic ability of the included angle of the anterior part, body and posterior part in the lateral meniscus measured by ultrasound to diagnose DLM are significantly better than other ultrasound measurement parameters, and the sensitivity and specificity of those parameters are close to MRI. Therefore, ultrasound can be used as a reliable method for preliminary diagnosis of DLM.

Clinical Results and Prognostic Factors of Arthroscopic Surgeries for Discoid Lateral Menisci Tear: Analysis of 179 Cases with Minimum 2 Years Follow-up

PURPOSE: The purpose of this study was to evaluate the clinical results and prognostic factors of arthroscopic surgeries for tears of the discoid lateral menisci. MATERIALS AND METHODS: From March 1997 to September 2005, 260 patients received arthroscopic surgeries due to discoid lateral menisci tears. Among these patients, 179 knees in 168 patients were followed up for at least 2 years and were enrolled into this study. The following prognostic factors were evaluated: sex, age, symptom duration, and type of meniscal tear. Visual analogue score (VAS), Lysholm score, and Ikeuchi grade were assessed as clinical results of arthroscopic surgeries. RESULTS: The mean VAS and Lysholm score improved at the last follow-up. According to the Ikeuchi grade, 104 cases were rated as excellent, 51 cases as good, and 23 cases as fair. Male sex (p<0.033), age younger than 20 years (p=0.0474), and symptom duration less than 12 months (p<0.044) were good prognostic factors. However, there was no correlation between tear types of discoid lateral menisci and clinical results. CONCLUSIONS: Sex, age, and symptom duration could be significant prognostic factors of arthroscopic surgeries for tears of discoid lateral menisci.

Treatment of the Snapping Discoid Lateral Meniscus without Tear in Pediatrics: Contouring Surgery and Posterolateral Repair

PURPOSE: To evaluate the results of arthroscopic contouring surgery and posterolateral meniscal repair for pediatrics with snapping discoid lateral meniscus without tear. MATERIALS AND METHODS: Nine children below 10 years, with snapping discoid lateral meniscus without tear were evaluated in this study. 3 cases had a morphologic deformity of lateral meniscus in MRI and arthroscopic findings, but there was no meniscal tear. Only contouring surgery was performed in 6 cases, and in 3 cases, because of the instability of meniscus over 5mm in traction due to the relaxation of the menisco-capsular junction after contouring surgery, posterolateral repair was performed. The average duration of follow up was 39 months(range, 25 to 72 months). RESULTS: Additional posterolateral repair was done due to remaining snapping, in three cases of six contouring surgery cases. In all cases, snapping was disappeared. The average Lysholm score was improved from 71 in preoperative status to 97 in postoperative status(p=0.008) CONCLUSION: In case of the increased instability of the posterolateral corner of lateral meniscus after contouring surgery in the treatment of snapping discoid lateral meniscus, posterolateral repair is effective to improve the snapping symptom from meniscal subluxation.

Treatment of discoid lateral meniscal tear by arthroscopic surgery: a report of 77 cases / 中国矫形外科杂志

[Objective]To report the treatment and outcome of treatment of discoid lateral meniscal tear by arthroscopic surgery.[Method]During the period between Jan.1999 and Jun.2005,77 patients suffered from discoid lateral meniscal tear have been treated by arthroscopic surgery in Xijing Hospital. The standard arthroscopic portals (anteromedial and anterolateral)were used.Lateral menisci were totally removed in the 21 patients (29.2%) of total 77 cases,whereas lateral menisci of 13 patients (18.1%) were removed partially and meniscus-plasty was applied in 38 patients (52.8%).Thirty-nine (54.2%) of 77 patients were males,and 33 (45.8%) females.Their average age was 29.4?10.9 years (range 8~51 year).Five patients were lost in follow-up.The mean follow-up period of the rest 72 patients was 26.2 ?9.3 months (range 12~44 months).The patients were assessed pre-operationally and post-operationally by the Lysholm score.Moreover,the results of Lysholm score were analyzed by student-t test.[Result]All patients had progress in pain,swelling,range of motion and knee function. No complication,which included intraarticular infection,iatrogenic injury,fibroarthritis or loss of range of motion,was found.Lysholm score was 66.8?5.2 in average (range from 50 to 78) before operation,whereas it improved to 96.4?3.6 in average (range from 85 to 100) after operation.According to student-t analysis,very significant statistical difference was found between the pre-operative and post-operative results (t=34.7,P

Discoid Lateral Meniscus in Children: Analysis of the Clinical Manifestations in relation to the Shape of the Discoid Lateral Meniscus / 대한정형외과학회잡지

PURPOSE: The clinical manifestations of discoid meniscus in children are usually different from those in adults. We attempted to find the relationship between the clinical symptoms and shape of discoid meniscus in children. MATERIALS AND METHODS: Thirty-one children, ranging from 5 to 17 years of age, with 32 discoid lateral menisci that underwent arthroscopic examination and MRI study were included. The clinical symtoms were reviewed by medical records. MR images were reviewed for the presence of meniscal tear and Wrisberg ligament, etc. Also, the absolute and relative thickness in anterior, posterior, mid-medial and mid-lateral portions were measured. The shape of the menisci were classified by the modified Hall's scheme. RESULT: The two most frequent complaints were pain (21 cases, 66.6%) and extension block (23 cases, 72.9%) . In 18 cases without surface tear, the most frequent clinical findings were extension block (14 cases, 78.8%) . The shape of the menisci correlated with the extension block. The mean thickness of the anterior portion of discoid lateral meniscus (7.12mm) in extension block (+) group was significantly larger than that (4.01mm) of the extension block (-) group (P=0.019) . The extension block was significantly higher in anterior asymmetric type (3/3) and slab type (19/21) than posterior asymmetric type (2/8) (P=0.003) . CONCLUSION: The main clinical symptoms in children with discoid meniscus were pain and extension block. The extension block seemed to strongly correlate with the shape of the meniscus. The thickness of the anterior portion of the discoid lateral meniscus is also considered a related mechanical factor that determines knee extension.

Arthroscopic Treatment of Symptomatic Discoid Lateral meniscus Without Tear

While there is little controversy about the surgical resection for the torn discoid lateral meniscus, there are some contradictory reports for the treatment of discoid lateral meniscus without tear. Some authors argue that initial treatment should be observation after diagnostic arthroscopy in the cases without tear. Others reported that excellent results were obtained after partial resection of the discoid lateral meniscus without tear or with slight degeneration. We reviewed our series of symptomatic discoid lateral menisci without tear, confirmed by arthroscopic examination. We retrospectively reviewed 8 knees in 8 patients who had had partia! Meniscectomy for discoid latera1 meniscus without tear, confirmed by arthroscopic examination. They were 5 males and 3 females. The average age was 22.8 years (range, 7 to 57 years). The average duration of follow-up was 2 years and three months. The patients had continuing pain and locking or snapping preoperatively. Preoperative MRI had grade Il intrameniscal signal in all the cases. The patients were evaluated hy Lysholm pain score and total Lysholm score. There were 7 complete types and one incomplete type. The average Lysholm pain score and the total Lysholm score improved from 13.1, 67.8 preoperatively to 28.8. 97.9, at the last follow-up, respectively. Mechanical symptoms including click and 1ocking were disappeared in all, and no complication was obser ved. We suggest that symptomatic discoid lateral meniscus should he resected e.ven though there is no tear visible on arthroscopy, especially when the MRl shows grade lI intrameniscal signal.