Multirater agreement of arthroscopic grading of knee articular cartilage

BACKGROUND: Acute and chronic cartilage injury of the knee has an important impact on prognosis. The validity of the classification of such injuries is critical for prospective multicenter studies. The agreement among multiple surgeons at different institutions for articular cartilage lesions has not been established. HYPOTHESIS: Arthroscopic classification of articular cartilage lesions is reliable and reproducible and can be used for multicenter studies involving multiple surgeons. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 1. METHODS: A total of 6 surgeons from 5 centers reviewed 31 videos of articular cartilage lesions. With grade 2 and grade 3 combined for the analysis, observed agreement ranged from 81% to 94%, and kappa ranged from 0.34 to 0.87. An additional 22 videos comprising grade 2 and grade 3 lesions were analyzed, and the observed agreement was 80%, with an overall kappa of 0.47. CONCLUSION: Arthroscopic grading of articular cartilage lesions is reproducible among surgeons at different centers. CLINICAL RELEVANCE: Articular cartilage lesions can be reliably classified among surgeons at different sites. Such reliability is important for multicenter clinical research studies involving arthroscopic knee surgery.     

Atrophy of thigh muscles after meniscal lesions and arthroscopic partial menisectomy

The purpose of this study was to investigate the atrophic pattern of the muscle groups and their individual muscles in the thigh after meniscal lesions and arthroscopic partial menisectomy. A total of 32 individuals (17 men and 15 women) who underwent arthroscopic knee surgery participated in this study. Their operated and non-operated thighs were scanned by magnetic resonance imaging to determine the volume of the quadriceps (QF), hamstring (HM), and adductors (AD). Compared with the non-operated limb, the volume of the QF was significantly lower in the operated limb; however, no significant difference was observed in the HM and AD. The volume of individual muscles of the QF, i.e. the rectus femoris (RF), vastus lateralis (VL), vastus intermedius (VI), and vastus medialis (VM), in the operated limb was significantly lower than the volume of those in the non-operated limb (P<0.01, all). Although the relative change in the VM was significantly higher than that of the RF (P<0.05), specific atrophy was not found among four individual muscles in the QF. We concluded that meniscal lesions and partial menisectomy induce atrophy in the QF only in the thigh, and that no specific atrophy, e.g. VM, seemed to occur within the individual muscles in the QF.     

Complications in arthroscopic meniscal surgery

Arthroscopic meniscal procedures as a whole have an acceptably low complication rate. The rate is no higher than the average for all arthroscopic procedures. In the hands of experienced arthroscopic surgeons the complication rate for meniscal repair is slightly lower than that for arthroscopic partial meniscectomy. Attention to anatomic detail, knee positioning, and proper surgical technique has resulted in a significant decrease in the incidence of major neurovascular injuries. The complication rate for outside-in meniscal repair is no lower than that for inside-out meniscal repair. Further refinements in surgical technique, suture materials, and instrumentation should result in an even lower complication rate. Ongoing studies to determine when the repaired meniscus has achieved clinical stability may allow earlier range of motion and further lessen postoperative stiffness.     

Lateral meniscal cyst: arthroscopic management

Thirty-six patients underwent arthroscopic cystectomy and partial meniscectomy for a lateral meniscal cyst. In two other patients, an open cystectomy was performed following a diagnostic arthroscopy. The patients were reviewed at an average of 39 months (range 8-82) after the operation, and recurrence was found in four cases. Five patients, all keen sportsmen, were dissatisfied with the operation. Four patients, with arthroscopic signs of early degenerative arthritis, were still experiencing some pain, but were able to lead a normal working and social life. Arthroscopy is safe, giving low morbidity and recurrence. In the cases treated by arthroscopy, a horizontal meniscal tear was always found. The question whether this tear and the resulting meniscal changes are traumatic or degenerative in origin still remains; and, to some extent, neither hypothesis can be readily discarded. This study supports the use of arthroscopy alone in the treatment of lateral meniscal cysts.     

Multirater agreement for grading the femoral and tibial cartilage surface lesions at CT arthrography and analysis of causes of disagreement

ObjectiveTo assess the multirater agreement of the modified Outerbridge system for the grading of predefined areas of femorotibial cartilage at CT arthrography with multiple readers, with varying experience.DesignFive readers with varying experience (two junior radiologists, three musculoskeletal radiologists including two experts in cartilage imaging) separately analyzed 962 cartilage sectors from pre-divided knee CT arthrograms with femorotibial osteoarthritis (Kellgren/Lawrence = 3). Each cartilage area was graded twice by each reader, at a three-month interval, according to the modified 5-grade Outerbridge system. Interobserver and intraobserver agreement were assessed. After the second reading, 121 areas exhibiting the highest interobserver disagreement were reviewed in consensus to determine the sources of disagreement.ResultsThe global interobserver agreement was fair (k = 0.35), and increased with the grade (from k = 0.14 to k = 0.76 from grade 0–4). The intraobserver agreement varied with the readers’ experience from moderate (k = 0.59) to almost perfect (k = 0.92). The majority of cases of disagreement (44%) was due to difficulties in assessing the normal variations of cartilage thickness, including diffuse cartilage thinning (23%) and normal variants of cartilage thickness (22%). 32% of cases of disagreement were due to retrospectively avoidable interpretation errors.ConclusionsThe multirater agreement of the modified Outerbridge system is only fair when readers of different level of experience are taken into account, and interobserver agreement increases with readers’ experience. However, interobserver agreement is substantial for grade 4 lesions. We report normal variations of cartilage thickness that may improve observer agreement in reporting cartilage lesions.     

Neuraland vascular complications of arthroscopic meniscal surgery

Injuries to vessels and nerves are very rare complications of arthroscopic meniscal surgery. The clinical development and diagnosis of such complications are described and illustrated by cases described in the literature and by two of our own cases. Typical patterns of injury are simulated by dissection of cadaver knees. To avoid neural complications in suturing the menisci, on the medial side the joint capsule has to be prepared when using the inside-out orthe outside-in technique. On the lateral side the outside-in technique can be performed by small suture incisions in this area when the lateral knee structures can be palpated. When using the inside-out technique the peroneal nerve must be dissected free. When resecting the posterior horn of the medial meniscus forced external rotation of the knee should be avoided because in this position the popliteal artery and the medial inferior genicular artery lie close to the posterior horn.     

History,clinical findings,magnetic resonance imaging,and arthroscopic correlation in meniscal lesions

Purpose  

The aim of this prospective study was to compare the accuracy of clinical examination and magnetic resonance imaging (MRI) versus arthroscopic findings and to determine the value of an experienced examiner in clinical decision making.     

T-Fix anchor sutures for arthroscopic meniscal repair

The results of arthroscopically repaired meniscal tears with the T-Fix system in a short-term follow-up of 6 months was assessed in a non-comparative, prospective study. The T-Fix device consists of a short, rigid Delrin T attached to a braided, non-absorbable, polyester suture which is preloaded inside and deployed through a delivery (spinal) needle. The T grabs inside the tissue and provides an anchor for the suture. Twenty menisci in 20 patients (mean age 29 years) were repaired. Sports-related injuries were documented in 18 patients. In 15 patients, meniscus tears were repaired 6 months or more after injury. Half of the patients had isolated meniscus injuries. Associated injuries included anterior cruciate ligament (ACL), medial or lateral collateral ligament ruptures. These were not treated at the time of meniscal surgery except for an ACL reconstruction. All tears were longitudinal and positioned mainly in the posterior horn of the medial meniscus. A total of 70 T-Fixes were used with an average of 3 per patient (range 2–7). Only 4 T-Fixes (6%) were unsuccessfully placed, and this occurred early on in the series in 4 patients. In 90% of the patients, the postoperative activity levels returned to preoperative levels, and the clinical symptoms had either resolved or were experienced at a higher level of activity. The T-Fix device was relatively easy to use and could be reliably placed in the meniscus. Postoperatively, there were no complications directly associated with the device. However, further studies are needed to confirmed these results in a long-term follow-up in a larger patient population.     

MR accuracy and arthroscopic incidence of meniscal radial tears

OBJECTIVE: A meniscal radial tear is a vertical tear that involves the inner meniscal margin. The tear is most frequent in the middle third of the lateral meniscus and may extend outward in any direction. We report (1) the arthroscopic incidence of radial tears, (2) MR signs that aid in the detection of radial tears and (3) our prospective accuracy in detection of radial tears. DESIGN AND PATIENTS: Three musculoskeletal radiologists prospectively read 200 consecutive MR examinations of the knee that went on to arthroscopy by one orthopedic surgeon. MR images were assessed for location and MR characteristics of radial tears. MR criteria used for diagnosis of a radial tear were those outlined by Tuckman et al.: truncation, abnormal morphology and/or lack of continuity or absence of the meniscus on one or more MR images. An additional criterion used was abnormal increased signal in that area on fat-saturated proton density or T2-weighted coronal and sagittal images. Prospective MR readings were correlated with the arthroscopic findings. RESULTS: Of the 200 consecutive knee arthroscopies, 28 patients had radial tears reported arthroscopically (14% incidence). MR readings prospectively demonstrated 19 of the 28 radial tears (68% sensitivity) when the criteria for diagnosis of a radial tear were truncation or abnormal morphology of the meniscus. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted or proton density weighted sequences, the prospective sensitivity was 25 of 28 radial tears (89% sensitivity). There were no radial tears described in MR reports that were not demonstrated on arthroscopy (i.e., there were no false positive MR readings of radial tears in these 200 patients). CONCLUSIONS: Radial tears are commonly seen at arthroscopy. There was a 14% incidence in this series of 200 patients who underwent arthroscopy. Prospective detection of radial tears was 68% as compared with arthroscopy when the criteria as outlined by Tuckman et al. were used alone. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted and proton density weighted sequences, the prospective sensitivity for radial tear detection as compared with arthroscopy was 89% in our series. Fat-saturated proton density and T2-weighted images greatly improve the detection of radial tears as signal intensity changes in radial tears as well as morphologic changes can be utilized for the detection of subtle tears.     

Clinical results of arthroscopic meniscal repair using biodegradable screws

This study was performed to assess the clinical results of meniscus refixation using biodegradable Clearfix meniscal screws. Between July 1999 and June 2001 this technique was performed on 65 patients, of whom 60 (27 women, 33 men; 92%) were followed up by clinical examination after an average of 18 months (range 8–34). The average age of the patients at the time of surgery was 30 years (15–58). Two patients had already undergone a partial meniscectomy at the time of follow up; three patients had had a recurrence of typical clinical signs of a meniscal tear. The other 55 patients rated the overall clinical result as "excellent" (n =21), "good" (n =31) or "satisfactory" (n =3). The average Lysholm score [20] at the time of examination was 93 (49–100) points. The Tegner-Lysholm activity grade [29] preinjury was 5.6 (3–9), compared to a grade of 5.1 (3–9) at the follow-up examination. As a result of our study, biodegradable screws can be recommended as fixation devices with a high rate of good and excellent clinical results.     

The arthroscopic meniscal repair. Techniques and clinical experience

Conservative meniscal repair should limit resection to only pathologic portions of the meniscus. The periphery of the meniscus is well vascularized, enabling healing of longitudinal tears. Sutures that perforate the meniscus vertically usually lead to stable healing. In arthroscopic meniscal surgery, isolated tears are sutured from within the joint, usually using techniques related to specially developed instrumentation. Our system uses three curved cannulas of various radii and a specific needle of 1.2 mm thickness, and can be operated by one hand while the joint is distracted with an AO/ASIF femoral distractor. In our series of 54 arthroscopic meniscal repairs, 42 (78%) healed without reinjury. Retears occurred in 12 patients, and were refixed again using the same techniques. Our experience has led us to conclude that the type of meniscal tear most suitable for arthroscopic repair is a vertical longitudinal lesion that involves the vascularized zone; abrading the synovial surfaces is helpful, as is positioning the sutures tightly together; the repair should be checked at 4 months by arthroscopy or by arthrogram; and a combination of nonabsorbable and resorbable sutures is most satisfactory. We believe that with experience arthroscopic meniscal repair becomes a less involved procedure than open repair, and that in the future such repair will be successfully extended to the more centrally located lesions.     

Prospective comparison of arthroscopic medial meniscal repair technique: inside-out suture versus entirely arthroscopic arrows

BACKGROUND: Medial meniscal repairs are commonly performed with inside-out sutures and entirely arthroscopic with arrows, but few comparative evaluations on failures have been performed. HYPOTHESIS: No differences in failure rates exist between medial meniscal repairs performed with inside-out suture or entirely arthroscopic at the time of anterior cruciate ligament reconstruction. STUDY DESIGN: Prospective cohort study. MATERIALS: A single surgeon performed 47 consecutive inside-out suture repairs from August 1991 to June 1996 and 98 consecutive entirely arthroscopic repairs with arrows from June 1996 to December 1999. All data were derived from a prospective database and rehabilitation was held constant (nonweightbearing 5 weeks). Clinical success was defined as no reoperation for failed medial meniscal repair. Statistical evaluation was by Kaplan-Meier curves and Cox proportional hazards model. RESULTS: The inside-out suture group had 85% follow-up (40 of 47) with a median 68 months and the entirely arthroscopic group had 87% follow-up (85 of 98) with a median 27 months. There were seven failures in each group. Both Kaplan-Meier curves and the Cox proportional hazards model showed no difference in time to reoperation between techniques (P = 0.85). Three-year success rates (proportions with no reoperations) were 88% for sutures versus 89% for arrows. CONCLUSIONS: Repairs of the longitudinal posterior horn of the medial meniscus during an anterior cruciate ligament reconstruction with nonweightbearing for 5 weeks can be performed with an equivalent high degree of clinical success for both repair techniques.     

膝关节半月板撕裂磁共振成像与关节镜对照研究

目的分析磁共振成像（MRI）在膝关节半月板撕裂诊断中的价值。方法分析168例（共计336个半月板）临床疑诊半月板损伤患者,依次在1周内行磁共振（MR）和关节镜检查,对比MR和关节镜检查结果,探讨MRI对膝关节半月板撕裂诊断符合率。结果以关节镜为参考标准,168例（共计336个半月板）中MRI诊断半月板撕裂敏感性96．9％,特异性为87．5％,准确性为92．5％,假阳性率为12．5％,假阴性率3．1％,MRI具有术前诊断价值。结论MRI诊断半月板撕裂具有很高准确性,但仍有一定的假阳性与假阴性。     

关节镜下手术治疗膝关节半月板囊肿17例体会

对17例膝关节半月板囊肿的患者在关节镜下行半月板成形术或修复术,对囊肿根据大小行切除术或内引流术。术前、后行疼痛视觉模拟评分（VAS）、Lysholm膝关节功能评分。13例获得长期随访,均未发现囊肿复发。关节镜手术治疗半月板囊肿,能够明确关节内病损,明显缓解术前关节疼痛症状,手术效果良好。     

Parameniscal cyst formation after arthroscopic meniscal repair with biodegradable meniscal arrow: a case report

A 22-year-old male underwent an arthroscopic meniscal repair, using meniscal arrows, due to bucket-handle medial meniscus tear. Magnetic resonance images (MRI) at 3 years revealed a large parameniscal cyst protruding into the extra-capsular popliteal space. Arthroscopic partial cystectomy, removing only the intra-articular portion of the cyst was performed, leaving the extra-articular part of the cyst. Sixteen months postoperatively MRI revealed no cyst remnants, and the patient was free of symptoms.     

Pull-out and shear failure strengths of arthroscopic meniscal repair systems

Meniscal repair is common and recommended in young patients. Suture techniques and fixation devices were developed for stronger, more facile repairs. Three devices (T-Fix, Meniscal Staple, Meniscus Arrow) were biomechanically compared to horizontal PDS suture. Peripheral tears were created in porcine menisci and repaired using the manufacturer's technique. An Instron was used to distract the menisci at 50 mm/min in axial-pullout and longitudinal shear loads. Load to failure curves and peak failure loads were noted. Load to failure in axially loaded pull-out mode was: Staple, 4.195+/-3.70 N; Arrow, 39.755+/-11.37 N; T-Fix, 45.892+/-13.99 N; Suture, 107.65+/-22.37 N. Analysis of variance with post hoc testing revealed Staple failure at lower load than all devices and Suture failure at higher loads than all devices; Arrow and T-Fix were similar. The data varied significantly from that obtained in shear. Shear loads to failure were: Staple, 8.39+/-8.62 N; Arrow, 27.67+/-14.33 N; T-Fix, 57.47+/-17.05 N; Suture, 64.15+/-17.05 N. Analysis of variance, power analysis, and pair-wise multiple comparisons revealed significant differences between: Suture and Staple, Suture and Arrow, and T-Fix and Staple. No differences were noted between Suture and T-Fix, T-Fix and Arrow, or Arrow and Staple. In pullout, Suture and T-Fix maintained better apposition at low loads. As load increased, the menisci separated until device failure. Arrows allowed low load separation but held tissue until failure. Staples failed at low load. For shear, the menisci attempted to reorient parallel to the force. The devices failed in a pull-slide pattern. Suture failed by pull-through. Meniscal repair devices are easy to use and may provide resistance to shear and pull out. The resistance to pullout loads was very different than the resistance to longitudinal shear loads.     

Significance of the arthroscopic meniscal flounce sign: a prospective study

BACKGROUND: The meniscal flounce sign is a fold in the free, nonanchored inner edge of the medial meniscus that can be noted during routine arthroscopy of the knee. HYPOTHESIS: The meniscal flounce sign can be a significant indicator of the presence or absence of medial meniscus injury. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 4. METHODS: One hundred sixty-eight patients were prospectively evaluated at the time of the arthroscopy for the presence or absence of the arthroscopic meniscal flounce sign. These results were then correlated with the presence of medial meniscus tears. RESULTS: The presence of the meniscal flounce sign has a positive predictive value of a normal meniscus of 0.97 (63/65). The absence of the meniscal flounce sign has a positive predictive value of an abnormal meniscus of 0.98 (101/103). Specificity is 98%, and sensitivity is 97%. CONCLUSION: The absence of the arthroscopic meniscal flounce sign is a sensitive and specific predictor of the presence of medial meniscus tears that should alert the surgeon to probe carefully for an occult medial meniscus tear.     

Anatomic and arthroscopic study of the medial meniscal horns’ insertions

The insertions of the menisci to the tibia are the most important restraints to extrusion from the knee joint, and are vital for the functional integrity of the menisci. The aim of the present study was to determine variations of tibial insertions of the medial menisci (MM) in newborn cadavers macroscopically and in adults by arthroscopy. Neonatal part of this study was performed on 40 knee joints of 20 Caucasian neonatal cadavers. Adult part was performed on 41 Caucasian adults, whose ages were between 17 and 66 unilaterally by arthroscopy. In neonatal cadavers, according to its insertion, anterior horn of MM was classified in five groups and type 4, in which it was inserted to the transverse ligament, was determined the most frequent one (45%) and posterior horn of MM was classified in three groups and type 3, in which it was inserted to both the posterior intercondylar area of tibia and medial tubercle of intercondylar eminence was determined the most frequent one (50%). In adults, anterior end of MM was most frequently inserted to both anterior intercondylar area of tibia and transverse ligament (76%) and posterior horn of MM was inserted to the posterior intercondylar area of tibia in all of them. This study provides comparative information about insertion of the MM for neonatals and adults, not to evaluate the variants of the insertion of the MM as a tear of the anterior cruciate ligament or a meniscal tear and not to complicate arthroscopy.     

An allogenic cell-based implant for meniscal lesions

BACKGROUND: Meniscal tears in the avascular zones do not heal. Although tissue-engineering approaches using cells seeded onto scaffolds could expand the indication for meniscal repair, harvesting autologous cells could cause additional trauma to the patient. Allogenic cells, however, could provide an unlimited amount of cells. HYPOTHESIS: Allogenic cells from 2 anatomical sources can repair lesions in the avascular region of the meniscus. STUDY DESIGN: Controlled laboratory study. METHODS: Both autologous and allogenic chondrocytes were seeded onto a Vicryl mesh scaffold and sutured into a bucket-handle lesion created in the medial menisci of 17 swine. Controls consisted of 3 swine knees treated with unseeded implants and controls from a previous experiment in which 4 swine were treated with suture only and 4 with no treatment. Menisci were harvested after 12 weeks and evaluated histologically for new tissue and percentage of interface healing surface; they were also evaluated statistically. RESULTS: The lesions were closed in 15 of 17 menisci. None of the control samples demonstrated healing. Histologic analysis of sequential cuts through the lesion showed formation of new scar-like tissue in all experimental samples. One of 8 menisci was completely healed in the allogenic group and 2 of 9 in the autologous group; the remaining samples were partially healed in both groups. No statistically significant differences in the percentage of healing were observed between the autologous and allogenic cell-based implants. CONCLUSION: Use of autologous and allogenic chondrocytes delivered via a biodegradable mesh enhanced healing of avascular meniscal lesions. CLINICAL RELEVANCE: This study demonstrates the potential of a tissue-engineered cellular repair of the meniscus using autologous and allogenic chondrocytes.