Torn discoid lateral meniscus treated using partial central meniscectomy and suture of the peripheral tear

We present the cases of 5 patients with a torn discoid lateral meniscus treated using partial central meniscectomy in conjunction with the suture repair of the tear. The patients were 4 boys and 1 girl with a mean age of 15.4 years (range, 11 to 17). Preoperatively, all patients complained of knee pain during daily or sports activities. At the final follow-up evaluation, more than 2 years later, 4 patients’ conditions were graded as excellent and 1 patient’s condition was graded as fair according to Ikeuchi’s grading scale. The average Lysholm score improved from 83.4 points (range, 70–90) to 95.8 points (range, 89–100) postoperatively. In the 3 patients who underwent second-look arthroscopy, complete healing was seen in 2 patients. One patient had severe degenerative changes in the meniscus; the repaired site was not united and required an additional partial meniscectomy along the tear. We believe that with the current advancement in arthroscopic meniscal repair techniques, a partial central meniscectomy in conjunction with the suture repair of the peripheral tear can be effective treatment for patients with a torn complete or incomplete discoid meniscus.     

Regeneration of ring-shaped lateral meniscus after partial resection of discoid meniscus with anterior cruciate ligament reconstruction

INTRODUCTIONThe ring-shaped lateral meniscus is very rare. Although it is essentially known as a congenital anomaly, a central tear in an incomplete discoid meniscus or an old bucket-handle tear in a meniscus may be easily mistaken for a ring-shaped meniscus. We experienced a ring-shaped lateral meniscus that regenerated after partial resection of a discoid meniscus together with anterior cruciate ligament (ACL) reconstruction.PRESENTATION OF CASEA 37-year-old female patient still experienced unrelenting knee pain 6 months after ACL reconstruction and partial meniscectomy of a discoid lateral meniscus. A repeat arthroscopy was performed. The lateral tibial plateau was covered in the form of a ring by meniscus-like tissue. The meniscus-like tissue appeared to have regenerated inward toward the center from the stump after the partial meniscectomy and was connected from the anterior to posterior horn, forming an interhorn bridge. Partial meniscectomy was repeated. Histologically, the regenerated tissue was not meniscal, but comprised mature fibrocartilage; macroscopically; however, it was very similar to meniscal tissue. Two years after the initial operation, the patient had no complaints and experienced full return of function.DISCUSSIONThe reason for such regeneration is unknown, but may have been attributed to the specific intra-articular environment that developed after the ACL reconstruction.CONCLUSIONThis is the first report of regenerative development of a ring-shaped lateral meniscus. When a ring-shaped lateral meniscus is diagnosed, we must accurately determine whether it is a true congenital anomaly in consideration of the present case.     

Lateral meniscal variant with absence of the posterior coronary ligament.

We reviewed the cases of 3468 patients who had had arthroscopy of the knee between January 1976 and December 1988. Twenty-six patients (0.8 per cent) had a partial or a complete discoid lateral meniscus, and seven (0.2 per cent) had the Wrisberg-variant-type lateral meniscus. Of the seven patients, six had operative stabilization of the meniscus and one had a partial lateral meniscectomy because of an irreparable complex tear. Subjective, objective, and radiographic evaluations were performed on the patients who had had stabilization of the meniscus. According to the scale of Tegner and Lysholm, the result was excellent in four patients, good in one, and fair in one. None of the six patients had a tear of the sutured meniscus after an average follow-up of thirty-two months (range, twenty-four to forty months). Two patients had progressive symptoms attributable to osteoarthrosis, but the changes in the articular cartilage had been present at the time of the index procedure. None of the seven Wrisberg-variant-type menisci demonstrated a true discoid shape of the meniscus. We therefore classified this lesion as a lateral meniscal variant with absence of the posterior coronary ligament.     

Meniscal allograft transplantation for symptomatic knee after meniscectomy of torn discoid medial meniscus: Report of three cases

In symptomatic discoid medial meniscus, partial meniscectomy is the principal treatment method and can yield promising short-term results. However, unlike the nondiscoid meniscus, discoid medial meniscus is frequently associated with horizontal cleavage tears, attributable to the presence of myxoid degeneration in the intrameniscal substance, in that it may potentially occur deteriorating long-term results because of re-tearing of remaining meniscus or secondary degeneration of cartilage of the medial compartment after meniscectomy. We experienced three rare cases of retear or secondary degeneration of cartilage of the medial compartment after meniscectomy for two patients with torn bilateral meniscus. Both patients were highly active young males. Meniscal allograft transplantation in complicated discoid medial meniscus was performed. At 2 years after meniscal allograft transplantation, clinical outcomes were improved with a normal range of motion. Orthopedic surgeons should recommend activity modification to prevent possible complicated injury of the discoid medial meniscus. Meniscal allograft transplantation may be an alternative option in highly active young patients undergoing complicated discoid medial meniscus to diminish pain, improve knee function, and prevent or delay degeneration.     

Anomalous insertion of the medial menisci

Many types of meniscal anomalies have been reported. The authors encountered two cases of anomalous insertion of the anterior horn of the medial menisci to the lateral femoral condyle, which ran up along the course of the anterior cruciate ligament (ACL), but was independent of the ACL. These anomalies were noted during arthroscopic examination and surgery of the ipsilateral knee for a torn discoid meniscus and a patellar fracture. A 34-year-old woman had a horizontal tear of the lateral discoid meniscus. We performed arthroscopic partial meniscectomy of the inner torn portion of the lateral discoid meniscus and contoured it to resemble a normal meniscus. An anomalous insertion of the medial meniscus was found on examination of the joint during surgery. A 32-year-old man had a patellar fracture and we performed reduction under arthroscopy and internal fixation with cannulated screws. The same anomalous insertion of the medial meniscus was also found on examination of the joint during surgery. We report the cases with a review of the literature.Arthroscopy 1998 Jul-Aug;14(5):505-7     

Plastic, partial meniscectomy for the discoid meniscus in children

Plastic, partial meniscectomy which preserves the marginal part of meniscal cartilage was carried out in our hospital for children with symptomatic lateral discoid meniscus. The post-operative results were good in almost all patients at the follow-up evaluation. We will report on the operative techniques and the post-operative evaluation of these cases. From June 1982 to December 1989, 34 discoid lateral menisci in 27 children under the age of 15 years were operated on Itabashi Hospital of Nihon University. After recognition of discoid meniscus with arthroscopy, plastic, partial meniscectomy was carried out via a small transverse skin incision, forming the edge of a normal meniscus. About 2/3 of the central part of a discoid meniscus was resected, leaving about 1.0 cm of its marginal part. The average duration of follow-up was 5 years 4 months. The post-operative results were rated on the basis of the JOA Score for Meniscus Injuries and for the present series stood at 92.9 points. Among these 27 children, 17 had been injured during sports activities and all of them returned to their previous activities except three. Radiologically, mild osteoarthritic changes were noted in only a few cases during the follow-up period. It was concluded that plastic, partial meniscectomy was one of the variable procedures in the treatment of symptomatic discoid meniscus in children.     

Radial Displacement of Lateral Meniscus After Partial Meniscectomy

Radial displacement or extrusion of the meniscus has been reported as a complication after meniscal transplantation and is sometimes observed in knees with advanced osteoarthritis. In this report, the case of a patient with radial displacement of the lateral meniscus after partial meniscectomy is presented. He had an incomplete discoid lateral meniscus with an anterior horn tear. The inner portion of the lateral meniscus was excised to leave a width of 8 to 10 mm. However, follow-up magnetic resonance imaging showed radial displacement of the mid-body of the lateral meniscus and a compatible finding of chondromalacia of the lateral compartment of the knee.     

膝盘状软骨的关节镜治疗

目的：探讨关节镜诊断治疗膝关节盘状软骨的作用。材料与方法：1995年9月－1999年12月关节镜治疗外侧盘状软骨38例。部分切除20例,次全切除14例,全切4例。结果：随访6个月－4年3个月,关节功能正常、症状消失30例。偶有疼痛3例,关节弹响1例,肌萎缩无改善2例,膝关节屈伸轻度受限2例。结论：盘状软骨镜下切除术保留软骨的宽度取决于盘状软骨的类型、撕裂范围和位置。保留的软骨应稳定、紧张;保留软骨形成的“半圆箍”应完整;术中活动膝关节无弹跳。     

Cautious surgery for discoid menisci

This retrospective study reviewed the outcomes of 43 knees in 38 patients with discoid menisci treated from 1977 to 1989. Patients underwent either no treatment, trimming, or subtotal or total resection. Approximately 40% of patients who underwent meniscectomy or partial meniscectomy had a fair or poor rating after an average follow-up of 6.5 years. Pathology demonstrating mucoid fibrinous degeneration within the discoid meniscus was found in many cases, showing abnormal meniscal tissue. Only one third of these knees had symptoms of locking, and only 20 (63%) of 32 had a positive arthrogram, demonstrating the diagnostic difficulties encountered with the discoid meniscus. Patients with a discoid meniscus who are symptomatic should undergo arthroscopy. A partial meniscectomy should be performed to achieve a smooth meniscus and a strong, stable peripheral rim.     

关节镜下盘状半月板的治疗

目的　探讨关节镜下盘状半月板的治疗方法与疗效。　方法　 37例 (37膝 )盘状半月板 ,33例行关节镜下成形术 ,4例肌腱部自关节囊缘较广泛撕裂因无法成形而行全切术。 1例自R区纵向撕裂在成形后行缝合修补术。　结果　按Ikeuchi氏膝关节评价等级 :优 19例 (5 1.4% ) ,好 13例(35 1% ) ,良 5例 (13 5 % )。　结论　关节镜下盘状半月板成形术可获得优良疗效 ,主张尽可能施行关节镜下成形术治疗盘状半月板。     

膝关节镜治疗老年人盘状半月板损伤

目的探讨膝关节镜治疗老年人盘状半月板损伤的疗效。方法对19例外侧盘状半月板损伤的老年患者进行关节镜手术,依具体损伤情况采用半月板成形术15例,次全切除术2例,全切除术2例。同时对伴随的骨关节炎、关节游离体、内侧半月板损伤、滑膜皱襞增生给予切除增生滑膜、关节软骨修整、游离体取出及内侧损伤半月板次全切除。结果18例获得随访,时间6～24（15±9）个月,按Ikeuchi膝关节评分标准：优13例,良2例,可2例,差1例。结论膝关节镜下治疗老年人盘状半月板损伤可以获得良好的效果。     

Analysis of the discoid meniscus in Koreans.

Discoid meniscus is a relatively common disorder of the knee in Koreans. Its arthroscopic treatment is one of the most technically demanding procedures of this field. The purposes of this study were to define the clinical features of the discoid meniscus in Koreans and to suggest an adequate arthroscopic technique. We performed arthroscopic meniscectomy on 37 knees with a lateral discoid meniscus. The average length of follow up was 21 months. The presence of synovial hypertrophy in the knee with discoid was significantly higher than that with a non-discoid meniscal lesion. A medial midpatellar portal for the arthroscope is advisable for clean arthroscopic surgery in this situation. We obtained satisfactory results through the partial resection of the discoid meniscus, leaving the normal semilunar-shaped meniscus intact as much as possible.     

Congenital discoid lateral meniscus in children. A follow-up study and evolution of management

Fifty-two children with 62 discoid lateral menisci were reviewed at an average follow-up of 5.5 years. Their average age at operation was 10.5 years and the mean delay in diagnosis was 24 months. Most of the children had vague and intermittent symptoms and the classical clunk was demonstrable in only 39% of the knees. An associated osteochondritis dissecans of the lateral femoral condyle was seen in seven knees. Forty-eight knees with symptomatic torn discoid menisci underwent open total lateral meniscectomy, six had arthroscopic partial meniscectomy and eight knees with intact discoid menisci, were left alone. Based on Ikeuchi's grading (Ikeuchi 1982), 37% of the knees had an excellent result, 47% had a good result and 16% had a fair result: none was poor. Arthroscopic partial meniscectomy is recommended only when the posterior attachment of the discoid meniscus is stable. A total meniscectomy is indicated for the Wrisberg-ligament type of discoid meniscus with posterior instability.     

Problems with repeated arthroscopic surgery in the discoid meniscus

To identify the main causes of repeated arthroscopic surgery of the knee joint and to find out the points of therapeutic approaches, we evaluated 139 patients who underwent arthroscopic meniscectomy in our department and in affiliated hospitals between 1983 and 1987. Two or more arthroscopic surgeries were needed in 9 knees of 8 patients (6.5%). In 5 knees with no known injuries, the primary reason for repeated surgery was horizontal tears of remnant meniscus after partial resection of lateral discoid meniscus. The most appropriate initial treatment for lateral discoid menisci in cases without tear should be observation of the clinical course with minimal treatment using diagnostic arthroscopy.     

Bucket handle tear of a discoid medial meniscus. Arthroscopic diagnosis--partial excision. A case report

A case of a rare, large discoid medial meniscus with a bucket-handle tear is described. The radiogram was normal and the clinical impression was torn medial meniscus. A diagnostic arthroscopy revealed an unusually large medial discoid meniscus with a bucket-handle tear. Open partial excision was performed following the arthroscopy.     

膝关节半月板损伤的关节镜微创治疗

目的 探讨膝关节半月板损伤在关节镜下治疗的方法以及疗效。方法 对165例膝关节半月板损伤患者应用膝关节镜诊治进行回顾性分析本组施行半月板部分切除成形术127例（其中包括部分切除及囊肿切除3例．盘状半月板部分切除成形术12例），大部分切除13例，全切除2例，表面修整10例，修补13例；同时行镜下前交叉韧带重建术47例，后交叉韧带重建7例，前、后交叉韧带同时重建2例，内侧皱襞切除术15例。结果137例患者后术后复查，追踪时间2～32个月，81例平均Lysholm-II评分为92分（前、后交叉韧带重建术56例不参与评分），较术前提高49分。结论 应用关节镜进行治疗半月板损伤可达到最大限度保留半月板，创伤小、恢复快、疗效佳，并可同时处理其他病变，诊断准确性高，避免漏诊。     

Partial meniscus arthroscopic resection

Arthroscopic meniscectomy was performed in 393 patients in the "three portal technique" in the years 1981 through 1983. The medial meniscus showed a bucket handle tear in 40.3% and a flap tear in 37.3% whereas the lateral meniscus showed a bucket handle tear in 12.2% and a flap tear in 46.1%. More than one third of the meniscus lesions were associated by chondromalacia of patella or femoral condyle. Arthroscopic meniscectomy was combined with shaving of the cartilage or shaving and arthroscopic subchondral drilling in 71 cases. Second-look arthroscopy was performed in 10 patients because of rupture of the remnant rim after the first partial meniscectomy.     

Arthroscopic meniscectomy for discoid lateral meniscus in children and adolescents: 4.5 year follow-up

We retrospectively reviewed the 4.5 year (range, 21-88 months) follow-up results of arthroscopic partial meniscectomies performed in 11 knees between 1994 and 2000 to treat a symptomatic discoid lateral meniscus. The average age at surgery was 11.5 years (range, 5-17 years). All except one of the discoid menisci were of a complete type, and all except three were torn menisci. At the latest follow-up examination, the result was excellent for nine knees, and good for two; no degenerative changes were evident on the roentgenograms. Arthroscopic partial meniscectomy should be the treatment of choice for the complete type symptomatic lateral discoid meniscus, even if it is intact. Preoperative lack of the knee extension requires a gentle rehabilitation program postoperatively.     

射频汽化仪在膝关节镜手术中的应用

目的探讨射频汽化仪在膝关节镜手术中的应用及其疗效。方法利用射频汽化仪对78例不同膝关节疾病患者进行关节镜手术,其中半月板部分切除18例,全切除7例,盘状半月板成形13例,损伤软骨及韧带修整21例,滑膜切除6例,髌骨外侧支持带松解5例,胫骨髁间隆突骨折固定6例,前交叉韧带重建2例。结果术后患侧膝关节肿胀轻,未见明显关节积液、积血。随访3～12个月,75例患者自觉症状良好,关节绞锁、疼痛等症状缓解;3例重度骨性关节炎者症状无缓解,转行人工关节置换术。膝关节功能评定：优46例,良29例,可0例,差3例,优良率96．2％。结论射频汽化仪具有良好的低温切除、止血作用,使用方便,有助于提高膝关节镜手术的效率及疗效。     

Management of discoid lateral meniscus tears: Observations in 34 knees

Purpose: The goal of this study was to evaluate arthroscopic partial resection of discoid lateral meniscus tears with an emphasis on radiographic evidence of degenerative changes after this procedure. Type of Study: Retrospective clinical study. Methods: Of 41 patients with an arthroscopic diagnosis of discoid meniscus over an 8-year period, 34 symptomatic lateral discoid meniscus tears in 33 patients were analyzed at an average follow-up of 5.6 years. The average age at operation was 19.8 years and most patients had vague and intermittent symptoms that caused delay in clinical diagnosis. Results: Eight patients were lost to follow-up and were excluded from the study. Magnetic resonance imaging, performed in 12 cases, and arthroscopy in all of these patients provided the precise diagnosis. All of the knees with symptomatic torn discoid menisci underwent arthroscopic partial meniscectomy. Only 1 Watanabe Wrisberg ligament type of discoid meniscus with posterior instability was totally meniscected. Based on Ikeuchi's grading, 39% of the knees had an excellent result, 46% had a good result, and 15% had a fair result; none of the results was poor. Conclusions: At an average 5-year follow-up, partial meniscectomy in patients with a Watanabe complete or incomplete discoid meniscus showed 85% good or excellent clinical results. However, a significant percentage of patients show femoral condyle flattening on radiography.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 19, No 4 (April), 2003: pp 346–352