Clinical and MRI evaluation of meniscal tears repaired with bioabsorbable arrows.

BACKGROUND AND AIMS: Excision of meniscal tissue has been shown to increase the risk of degenerative changes of the knee joint. Whenever possible, meniscus repair has become the procedure of choice for treatment of meniscal tears. MATERIALS AND METHODS: The present retrospective study evaluated the healing results of 77 meniscal ruptures treated with the an all-inside technique (Biofix meniscus arrow). The study group consisted of 73 patients with 77 longitudinal, vertical meniscal ruptures treated at Helsinki University Hospital between the beginning of January 1997 and the end of March 2001. The patients who had not received secondary surgery for failed repair during the follow-up period were examined clinically and with MRI. RESULTS: Fifty-one out of 77 meniscal ruptures (66%) healed clinically. In repairs performed in conjunction with ligament reconstruction the healing rate was higher (79%) than in the isolated tears (56%). The poorest results were seen in the very long vertical tears with luxation of the meniscus (38% healing rate). CONCLUSIONS: Bioabsorbable arrows offer a good alternative for treatment of meniscal ruptures, but the arrows alone do not seem to be sufficient to provide a reliable long-lasting result in the repair of very unstable meniscal ruptures.     

Meniscus Tears: Treatment in the Stable and Unstable Knee

Basic science research and follow-up studies after meniscectomy have provided convincing evidence of the importance of preservation of the meniscus in decreasing the risk of late degenerative changes. Whether in a stable or an unstable knee, if a meniscus tear cannot be repaired, a conservative partial meniscectomy should be undertaken to preserve as much meniscal tissue as possible. When feasible, repair should be carried out in young patients with an isolated meniscus tear, despite healing rates that are significantly lower than those obtained when meniscus repair is done with anterior cruciate ligament (ACL) reconstruction. The incidence of successful healing is inversely related to the rim width and tear length. In general, meniscus repair should be limited to patients under 50 years of age. Vertical longitudinal tears, including bucket-handle tears, are most amenable to repair. Some radial split tears can be repaired. In an ACL-deficient knee, meniscus repair is more prone to failure if not performed in conjunction with an ACL reconstruction, and is not recommended. Meniscal allograft surgery is investigational but may hold promise for selected patients.     

Meniscus pathology, osteoarthritis and the treatment controversy

The menisci are internal structures that are of central importance for a healthy knee joint; they have a key role in the structural progression of knee osteoarthritis (OA), and the risk of the disease dramatically increases if they are damaged by injury or degenerative processes. Meniscus damage might be considered a signifying feature of incipient OA in middle-aged and elderly people. As approximately every third knee of people in these groups has a damaged meniscus, tears are common incidental findings of knee MRI. However, as most tears do not cause symptoms, careful clinical evaluation is required to determine if a damaged meniscus is likely to directly impact a patient's symptoms. Conservative management of patients with knee pain and a degenerative meniscal tear should be considered as a first-line therapy before surgical treatment is contemplated. Patients with mechanical interference of joint movements, such as painful catching or locking, might need surgical treatment with meniscal repair if possible. In a subset of patients, meniscal resection might relieve pain and other symptoms that potentially originate directly from the torn meniscus. However, the possibility of an increased risk of OA if functional meniscal tissue is removed cannot be overlooked.     

Meniscal Root Tears

Meniscus root tears are a specific type of meniscal injury that have gained attention over the past 5 years and have been reported to account for 10% to 21% of all meniscal tears, affecting nearly 100,000 patients annually. Meniscal root tears either are defined as an avulsion of the insertion of the meniscus attachment or complete radial tears that are located within 1 cm of the meniscus insertion. Biomechanical studies have demonstrated that meniscal root injuries interrupt the continuity of the circumferential fibers, and hence lead to failure of the normal meniscal function to convert axial loads into transverse hoop stresses. The most common presenting symptoms in meniscal root tears are posterior knee pain and joint line tenderness, especially with deep squatting.Another common symptom is a popping sound heard while participating in light activities such as ascending stairs or squatting. Magnetic resonance imaging signs of medial meniscus root tears include: (1) medial meniscal extrusion of ≥3 mm in a coronal section; (2) high signal indicating a disruption of the posterior meniscal root region in an axial view; and (3) a “ghost sign,” which is the absence of an identifiable meniscus in the sagittal plane, or increased signal replacing the normally dark meniscal tissue signal at the posterior root attachment. Active patients, regardless of age, should be referred early and considered for a meniscal root repair. Indications for a meniscal root repair include acute, traumatic root tears in patients with nearly normal or normal cartilage and chronic symptomatic root tears in young or middle-aged patients without significant preexisting osteoarthritis.Meniscal root repair has been demonstrated to have high satisfaction rates and superior outcomes to arthroscopic meniscectomy for root tears. To restore the function of the meniscus after medial meniscus root tears, a transosseous meniscal root repair technique is most commonly used. The advantage of this technique is the ability to reduce and fix the meniscal root to the broad anatomic footprint to maximize its healing potential. In addition, the transtibial tunnels may contribute to the release of biological factors that can enhance the healing of the meniscal root repair.     

Stage-based treatment by partial meniscectomy, meniscal refixation and transplantation

Clinical and experimental studies have demonstrated that the meniscus is important for normal knee function. Loss of meniscus results in abnormal load transmission across the knee and may lead to degenerative joint disease. Preservation of meniscal tissue is therefore important. About 10 % of all meniscal tears are repairable. The most successful repairs occur in younger patients who have an acute, vertical tear in the vascular portion of the meniscus. Currently, arthroscopic meniscal repair procedures include the inside-out, the outside-in and the all-inside technique. Vertical suture techniques are superior to horizontally placed sutures. From a biomechanical point of view, 2-0 to 1 sutures are recommended for suture repair. Various meniscus implants are also available for meniscal repair. The initial fixation strength of the implants is lower compared to vertical sutures. A combination of suture techniques and implants might be a treatment option in posterior meniscal lesions. The collagen meniscus implant has been designed to support tissue ingrowth after segmental medial meniscectomy. Although fibrocartilage matrix formation has been shown, long-term clinical follow-ups are still required. Meniscal allograft transplantation may be indicated in limited situations. Younger patients with meniscal deficiency due to previous meniscectomy who have only early arthrosis, normal axial alignment, and a stable knee may currently considered appropriate candidates for meniscal transplantation.     

Meniscal repair and transplantation: indications, techniques, rehabilitation, and clinical outcome

The purpose of this paper is to provide current knowledge regarding the indications, operative techniques, rehabilitation programs, and clinical outcomes of meniscus repair and transplantation procedures. Meniscus tears that occur in the periphery may be repaired using a variety of operative procedures with high success rates. Complex multiplanar tears that extend into the central one-third avascular zone can also be successfully repaired using a meticulous vertically divergent suture technique. The outcome of these repairs justifies preservation of meniscal tissue, especially in younger athletic individuals. Meniscal transplantation is a valid treatment option for patients who have undergone meniscectomy and have related tibiofemoral joint pain, or in whom articular cartilage deterioration in the meniscectomized compartment is present. Rehabilitation after these operations includes knee motion and quadriceps-strengthening exercises initiated the first day postoperatively. The initial goal is to prevent excessive weight bearing and joint compressive forces that could disrupt the healing meniscus repair or transplant. The protocol contains modifications according to the type of meniscal tear, if a concomitant procedure is done (such as a ligament reconstruction) or if noteworthy articular cartilage deterioration is present. Patients who have repairs of peripheral meniscus tears are generally progressed more rapidly than those who have repairs of tears extending in the central one-third region or those who undergo meniscal transplantation. The safety and effectiveness of the rehabilitation program has been demonstrated in several clinical studies. We recommend preservation of meniscal tissue, regardless of age, in active patients whenever possible.     

Editorial Commentary: All-Inside Double-Vertical Cross-Suture is an Effective Technique for Knee Meniscus Radial Tear Repair,but There is No Gold-Standard Evaluation Tool for Evaluating Healing and Function of the Repaired Meniscus

Treatment of radial tears of the lateral meniscus is challenging. Previous studies after repairing radial tears showed low healing rates. Various suture techniques are now being developed, and biomechanical and clinical studies using these new techniques are underway. Amid development, the all-inside double vertical cross-suture technique seemed to be effective. However, limited evaluations after meniscal repair might not fully reveal whether the repaired meniscus can maintain its function. Because the best single method that can completely evaluate meniscal healing and its function after repair is still lacking, we should introduce various assessments and consider them in a comprehensive way.     

Clinical results of meniscus repair in patients 40 years and older

The critical role that the meniscus plays in the knee along with the advantages of preserving as much of the meniscus as possible have both been well documented. Whenever possible, meniscus repair has become the procedure of choice for treatment of meniscal tears. However, some researchers have reported less favorable results in older patients. To determine the results of meniscus repair in older patients, patients 40 years and older who underwent arthroscopically assisted meniscus repair were prospectively followed up. Thirty-seven patients were included in the study, all of which had a minimum 2-year follow-up (average, 26.5 months). The average age of the patients at the time of the repair was 44.2 years (range, 40 to 52 years); 26 were males and 11 were females. There were 19 left knees and 18 right knees included in the study. Twenty-two patients had associated anterior cruciate ligament reconstructions. Physical examination at follow-up included swelling, joint line tenderness, locking, and McMurray testing and radiographs. Five of 37 menisci repaired (13.5%) were symptomatic at latest follow-up. All of these patients had joint line tenderness and two had a positive McMurray test. Three of these patients had repeat arthroscopy confirming that the meniscus had not healed. Because of the small number of patients with symptoms at follow-up, the authors feel that meniscus repair in patients 40 years and older is an effective treatment for peripherally located meniscus tears. With 86.5% of the patients having good clinical results, these findings are comparable with other studies with a younger population and signify that repair of peripheral tears is indicated in this age group especially in conjunction with anterior cruciate ligament reconstruction. The findings suggest that the location and meniscal tear, rather than the age of the patient, determine the potential for successful repair. (Arthroscopy 1998 Nov-Dec;14(8):824-9.)     

The surgical approach to lateral meniscal repair.

Peripheral lateral meniscal tears are amenable to meniscal repair. Rasp abrasion and fibrin clot deposition along with vascular access channels are advances that, one hopes will increase healing rates of meniscal repairs. A basic principle that is not emphasized in the literature is how to perform the surgical approach to the lateral meniscus for safe placement of a meniscal repair retractor. This article reviews the anatomical planes of which the surgeon must be cognizant to facilitate retractor placement.     

Editorial Commentary: Combined Anterior Cruciate Ligament Reconstruction and Medial Meniscal Transplantation Improve Functional Outcomes When Properly Indicated

The anterior cruciate ligament (ACL) and medial meniscus both contribute to anteroposterior translation of the tibia. Biomechanical studies have found increased translation at both 30° and 90° when transecting the posterior horn of the medial meniscus, and clinically, medial meniscal deficiency has been shown to have a 46% increase in ACL graft strain at 90°. Medial meniscal deficiency is a risk factor for failure after ACL reconstruction, with a hazard ratio of 15.1. The combination of meniscal allograft transplantation and ACL reconstruction is technically demanding but results in mid- to long-term clinical improvement in well-indicated patients. Patients with medial meniscal deficiency and failed ACL reconstruction or with ACL deficiency and medial-sided knee pain due to meniscal deficiency are candidates for combined procedures. On the basis of our experience, acute meniscal injury is not an indication for primary meniscal transplantation in any setting. Surgeons should repair the meniscus if reparable or perform partial meniscectomy and see how the patient responds. There is insufficient evidence to show that early meniscal transplantation will be chondroprotective. We reserve this procedure for the indications previously described. Severe osteoarthritis (Kellgren-Lawrence grades III and IV) and Outerbridge grade IV focal chondral defects of the tibiofemoral compartment that are not amenable to cartilage repair are absolute contraindications to the combined procedure.     

Posterior meniscal root injuries

ABSTRACT — Meniscal root tears (MRTs) are defined as radial tears within 1?cm of the meniscal root insertion, or an avulsion of the insertion of the meniscus. These injuries change joint loading due to failure of the meniscus to convert axial loads into hoop stresses, resulting in joint overloading and degenerative changes in the knee. Meniscal root repair is recommended in patients without advanced osteoarthritis (Outerbridge 3–4), in order to restore joint congruence and loading and therefore to avoid the long-term effect of joint overloading. Several techniques have been described. Improved knee function has been reported after meniscal root repair, but there are still conflicting reports on whether surgical treatment can prevent osteoarthritis.     

Approach to meniscal tears in anterior cruciate ligament reconstruction

It is generally accepted that meniscus repair in a knee with persistent anterior cruciate ligament (ACL) insufficiency leads to a higher retear rate, and that meniscal repair in conjunction with ACL reconstruction is associated with a higher rate of meniscal healing compared with patients who do not undergo ACL reconstruction. In this article, we will review the background of thses concepts and present treatment strtegies for meniscal tears in ACL-insufficient knees, with particular attention to meniscal repair and meniscal allograft transplanatation.     

Meniscal injury: II. Management

Meniscal repair is a viable alternative to resection in many clinical situations. Repair techniques traditionally have utilized a variety of suture methods, including inside-out and outside-in techniques. Bioabsorbable implants permit all-inside arthroscopic repairs. The success of meniscal repair depends on appropriate meniscal bed preparation and surgical technique and is also influenced by biologic factors such as tear rim width and associated ligamentous injury. Successful repair in >80% of cases has been reported in conjunction with anterior cruciate ligament reconstruction. Success rates are lower for isolated repairs. Complications related to repair include neurologic injury, postoperative loss of motion, recurrence of the tear, and infection. Meniscal allograft transplantation may provide a treatment option when meniscus salvage is not possible or when a previous total meniscectomy has been done.     

Allogeneic deep frozen meniscal graft for repair of osteochondral defects in the knee joint

Osteochondral defects in the knee joints of five patients caused by trauma or osteochondritis dissecans were repaired using deep-frozen allogeneic meniscal grafts. Three patients were male and two were female, with a mean age of 26.4 years. The mean follow-up period was 31 months. Postoperative magnetic resonance imaging (MRI) at all periods clearly showed a smooth and congruous articular surface, although the signal intensity of the grafted meniscus was not the same as that of the articular cartilage. Second-look arthroscopy performed approximately 1 year after surgery demonstrated that the grafted meniscus was well bonded to the grafted site, not sunken; there was no gap between the grafted meniscus and the surrounding articular cartilage, indicating that the grafted meniscus functions as a part of the articular surface. Histologic examination revealed that host cells had infiltrated into the meniscus and that cells surrounded by thin collagen fibrils were morphologically similar to fibrochondrocytes. Thus, the acellular grafted meniscus regenerated as meniscal tissue and formed an articular surface, although hyalinization did not occur. Our results suggest that deep-frozen allogeneic meniscal grafting is a useful method to repair osteochondral defects in the knee joint.     

Outcomes of meniscal repair: minimum of 2-year follow-up

PURPOSE: The purpose of this study was to determine the success rate of meniscal repair achieved in our sports medicine practice, particularly with interest in characterizing the outcomes observed with the newer all-inside repair devices. TYPE OF STUDY: Retrospective chart review with telephone follow-up. METHODS: 157 patients that had undergone a meniscal repair procedure between 1996 and 2001 were identified. Twenty-four of these patients were lost to follow-up. Thus, the study group consisted of 133 patients providing a follow-up rate of 85%. All patients included had a minimum of two years of follow up. Failure was defined as the need for meniscectomy in the area of the meniscus that was initially repaired. The time interval from injury to surgery was divided into less than six weeks (acute) and greater than six weeks (chronic). The etiology of the meniscal tear was broken down into three categories; sports related trauma, non-sports trauma, and atraumatic. The repair techniques used in these patients included outside-in sutures, inside-out sutures, darts, arrows, meniscal screws, T-fix, FasT-fix, and the RapidLoc. RESULTS: The failure rate was 36%. No association was found between failure and the length of preoperative symptoms, rim width, etiology, concomitant meniscectomy, chondroplasty or anterior cruciate ligament (ACL) reconstruction. There was a higher rate of failure of tears in the medial versus lateral meniscus (20.3% vs. 44.8%). No statistical comparisons could be made between devices due to small sample sizes. CONCLUSIONS: The all-inside meniscal repair devices have simplified the meniscal repair procedure. This may have lead to a broadening of the indications for repair CLINICAL RELEVANCE: The newer generation meniscal repair devices, while simplifying the procedure, do not appear to lead to an increased clinical success rate.     

Patient outcomes following T-Fix meniscal repair and a modifiable,progressive rehabilitation program,a retrospective study

INTRODUCTION: This retrospective study presents clinical patient outcomes following meniscal repair using T-Fix devices and a modifiable, progressive rehabilitation program. MATERIALS AND METHODS: Fifty-two patients (35 males and 17 females) with a mean age of 26.7 years (range 13-50 years) representing all of the patients who underwent arthroscopic meniscal repair (43 medial meniscus, 12 lateral meniscus) over a 3-year period by the same surgeon (D.C.) (55 menisci) participated in this study. Thirty-two of the patients (62%) had an associated ACL tear. All patients with an ACL tear underwent reconstruction (tibialis anterior allograft) at the time of meniscal repair. All meniscal tears were located in either the red-red zone (29) or the red-white zone (26). All patients who underwent meniscal repair participated in a modifiable (based on meniscal tear size, type, and location) progressive rehabilitation program. Operative notes and photographs were reviewed to identify the meniscal tear location, tear type, tear length, and the number of T-Fix devices used. Orthopedic clinic and physical therapy reports were also reviewed for postoperative range of motion, knee joint effusion, knee joint pain, McMurray test findings, and single-leg broad-jump test performance (90% bilateral equivalence goal). The average postoperative clinical follow-up period was 10.3 months (range 4-24 months). RESULTS: Most (22/23, 96%) patients who underwent meniscal repair alone displayed excellent results. All patients (32/32, 100%) who underwent combined ACL reconstruction-meniscal repair displayed excellent results. During an acute event such as a sudden directional change while running or contact with another player, 5 of these patients re-injured their meniscus at the repair site in conjunction with tearing the reconstructed ACL at 12+/-3 months following the index surgical procedure. Each of these 1-2 cm meniscal tears had been previously repaired with two T-Fix devices. CONCLUSION: The T-Fix device used in combination with a modifiable progressive rehabilitation program produced excellent clinical patient outcomes among this patient group.     

Isolated revision meniscal repair – failure rates,clinical outcome,and patient satisfaction

Background

Failure of isolated primary meniscal repair must be expected in approximately 10–25% of cases. Patients requiring revision surgery may benefit from revision meniscal repair, however, the results of this procedure remain underreported. The purpose of this study was therefore to evaluate the outcome and failure rates of isolated revision meniscal repair in patients with re-tears or failed healing after previous meniscal repair in stable knee joints.

Methods

A chart review was performed to identify all patients undergoing revision meniscal repair between 08/2010 and 02/2016. Only patients without concomitant procedures, without ligamentous insufficiency, and a minimum follow-up of 24?months were included. The records of all patients were reviewed to collect patient demographics, injury patterns of the meniscus, and details about primary and revision surgery. Follow-up evaluation included failure rates, clinical outcome scores (Lysholm Score, KOOS Score), sporting activity (Tegner scale), and patient satisfaction.

Results

A total of 12 patients with a mean age of 22?±?5?years were included. The mean time between primary repair and revision repair was 27?±?21?months. Reasons for failed primary repairs were traumatic re-tears in 10 patients (83%) and failed healing in two patients (17%). The mean follow-up period after revision meniscal repair was 43 (± 23.4) months. Failure of revision meniscal repair occurred in 3 patients (25%). In two of these patients, successful re-revision repair was performed. At final follow-up, the mean Lysholm Score was 95.2 (± 4.2) with a range of 90–100, representing a good to excellent result in all patients. The final assessment of the KOOS subscores also showed good to excellent results. The mean Tegner scale was 6.8?±?1.8, indicating a relatively high level of sports participation. Ten patients (83%) were either satisfied or very satisfied with the outcome.

Conclusion

In patients with re-tears or failed healing after previous isolated meniscal repair, revision meniscal repair results in good to excellent knee function, high level of sports participation, and high patient satisfaction. The failure rate is slightly higher compared to isolated primary meniscal repair, but still acceptable. Therefore, revision meniscal repair is worthwhile in selected cases in order to save as much meniscal tissue as possible.

     

应用Fast—Fix关节镜下修复半月板损伤

目的探讨Fast—Fix在关节镜下半月板损伤修复中的应用,并尝试对其手术技巧与疗效进行相关分析。方法选择本组59例在关节镜下应用Fast—Fix半月板缝合装置缝合的半月板撕裂的患者,其中陈旧性损伤31例,新鲜损伤28例,应用Fast—Fix缝合数目1～3个。术后根据MRI随访,并进行膝关节Lysholm评分及膝关节半月板损伤后JOY疗效评分。结果半月板平均缝合时间为5min。患者平均随访15个月,术后3个月MRI复查,半月板愈合率91％。术后患者的膝关节Lysholm评分、JOY疗效评分与术前比较,差异有统计学意义（t=5．215,P〈0．01）,疗效的优良率为89％。结论应用Fast—Fix在关节镜下行半月板撕裂缝合,方法简便,易于操作,固定牢靠,术后半月板愈合率高,是一种方便、有效的完全关节镜下半月板缝合技术。     

Meniskusrefixierung: Faden oder Anker?

Suture techniques are the standard for fixation of meniscus bucket-handle lesions. In 1993 a new method for meniscus repair with self-reinforced biodegradable "arrows" was introduced. Currently, various meniscus implants are available in Germany and are widely used clinically. The purpose of this paper was to evaluate and discuss the literature on biodegradable meniscus implants. Relevant articles were retrieved from Medline of the National Library of Medicine (1966 until July 2000) using the combined search strategy for the keywords "meniscal repair" and "arrow." Ten publications were found. The reported advantages of meniscus arrows are the reduced operation time, the easy surgical technique, and the reduced risk of neurovascular injury. In most experimental studies, lower failure strength of meniscus arrows was found compared to meniscus sutures. In clinical studies, the meniscal healing rates comparing the arrow technique and suture technique are comparable. Various complications of the new arrow technique have been reported such as inflammatory foreign-body reaction, cartilage lesions, and arrow displacement. Based on the existing literature, no final judgment is possible. Currently, individual indications depending on the kind of meniscal lesion and location are recommended. A combination of suture and arrow technique might be a treatment option, but further prospective randomized studies and longer follow-ups are necessary.     

Second look arthroscopic evaluation of repaired radial/oblique tears of the midbody of the lateral meniscus in stable knees

Background

Radial/oblique tears of the midbody of the lateral meniscus significantly impair the ability of the meniscus to withstand the tibiofemoral load, requiring meniscal repair. However, healing status after meniscal repair has not been fully elucidated. This study aimed to evaluate arthroscopic findings after inside-out suture repair for isolated radial/oblique tears of the midbody of the lateral meniscus.