Arthroscopic all-inside repair techniques of lateral meniscus anterior horn tear: a technical note

Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus, it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule. Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus.     

Arthroscopic all-inside repair of Palmer type 1B triangular fibrocartilage complex tears: a technical note

Arthroscopic repair of peripheral dorso-ulnar triangular fibrocartilage complex (TFCC) lesions is now a preferred method. Both outside-in and inside-out techniques are commonly performed for repairing Palmer type 1B TFCC tear. But these techniques have disadvantages of making an additional skin incision to tie knots subcutaneously over the capsule. We performed an arthroscopic all-inside repair technique of Palmer type 1B TFCC tears, which is a modified method of the outside-in technique using a spinal needle. This all-inside technique is as simple as previously described arthroscopic techniques and also has advantages of vertical mattress suture and no additional incision. We recommend this technique as a useful alternative to the others for repairing Palmer type 1B TFCC tear.     

The modified outside-in suture: vertical repair of the anterior horn of the meniscus after decompression of a large meniscal cyst

This article describes a modified suture technique designed for the vertical repair of the anterior horn of the meniscus after arthroscopic decompression of a large meniscal cyst. This procedure comprises of three steps: first, the meniscus was pierced vertically using a suture hook and a No. 0 PDS suture. Second, both ends of the No. 0 PDS on the femoral and tibial surfaces of the meniscus were pulled to the outside of the joint capsule using a spinal needle preloaded with suture material. Finally, a skin incision was made adjacent to the suture materials, and both ends were tied. We recommend this technique not only for the vertical repair of the anterior horn of the meniscus after decompression of large meniscal cyst, but also to repair a longitudinal tear of the meniscus.     

Current status of meniscus salvage

The direct repair of meniscus tears with rasp preparation of all tear surfaces, stable suture fixation, and exogenous clot injection is effective for single longitudinal tears with peripheral white rims of 4 mm and less. Radial split and flap tears at the posterior horn of the lateral meniscus can be directly repaired as well. Single longitudinal tears typically in chronic knees with peripheral white rims of 5 mm and greater may have better reliability with use of the fascia sheath. The sheath is indicated in complex tears including flaps and radial splits. A structured rehabilitation program is necessary for improved reliability of meniscus healing. Tears out in the white substance are significantly more sensitive to rapid return to weight bearing than the peripheral tears or the ligament-reconstruction portions of the procedure. Contraindications to meniscus repair would include short tears (less than 10 mm), stable partial thickness tears with less than 50% of the vertical height of the meniscus torn, and shallow radial tears of 3 mm depth or less. A posterior incision and use of the popliteal retractor at all times are necessary for protection of the popliteal neurovascular structures.     

Meniscus root repair

Root tears are a subset of meniscal injuries that result in significant knee joint pathology. Occurring on either the medial or lateral side, root tears are defined as radial tears or avulsions of the posterior horn attachment to bone. After a root tear, there is a significant increase in tibio-femoral contact pressure concomitant with altered knee joint kinematics. Previous cadaver studies from our institution have shown that root repair of the medial meniscus is successful in restoring joint biomechanics to within normal limits. Indications for operative management of meniscal root tears include (1) a symptomatic medial meniscus root tear with minimal arthritis and having failed non-operative treatment, and (2) a lateral root tear in associated with an ACL tear. In this review, we describe diagnosis, imaging, patient selection, and arthroscopic surgical technique of medial and lateral meniscus root injuries. In addition we highlight the pearls of repair technique, associated complications, post-operative rehabilitation regimen, and expected outcomes.     

Outside-in meniscus repair: the last 25 years

Recent advances in our understanding of knee biomechanics and load transmission have emphasized the need for meniscus preservation. However, the literature suggests that more needs to be done. The outside-in arthroscopic meniscus repair was first described by Warren in 1985. Despite the popularity of new all-inside meniscus repair devices, the outside-in meniscus repair technique is still used by many surgeons to preserve the meniscus. During the last 26 years, this technique has evolved and modified. However, its basic principles as being a minimally invasive, simple, and inexpensive meniscus repair technique have not changed. The results of outside-in meniscus repair have also stood the test of time, yielding healing rates and functional scores comparable to those of other meniscus repair techniques.     

Use of the fascia sheath coverage and exogenous fibrin clot in the treatment of complex meniscal tears.

In a previous series, complex meniscal tears, including double flap, double longitudinal, and radial tears, there was reported a high failure rate (14 of 58 repairs, 24%) when treated by conventional arthroscopic repair techniques. There was only one tear in the anterior middle one-third of the lateral meniscus in this group. The use of a fascia sheath to cover the repaired area improves healing rates an additional 17% (from 75% to 92%) with these tear classifications, with the exception of radial split tears in the middle one-third of the lateral meniscus. The present repair technique includes rasp abrasion of the parameniscal synovium, peripheral white rim, and tear surface of the handle fragment. The meniscus is sutured with fully diverged sutures. A rectangle of fascia from the distal anterolateral thigh, trimmed to 25 x 35 to 40 mm, is prepared with the double-armed meniscus suture run along opposite sides. One or two "hold-down" sutures are tied to the superior and inferior main sutures. The four hold-down sutures from the corners and the previously placed hold-down sutures are pulled through the capsule with previously placed pull-through sutures to pull the fascia over the meniscal repair. The exogenous blood clot is injected in the tear under the sheath. This preliminary report suggests that improved healing rates can be obtained with most complex tears by meticulous meniscal repair followed by coverage with the fascia sheath and then exogenous clot injection. Repairs of tears in the middle one-third of the lateral meniscus still show a high failure rate.     

Under-meniscal portal: an alternative portal for an easy access to the medial and lateral menisci

Approach to the pathologies in the posterior horn of the medial meniscus in a tight knee may be a challenging technique to the arthroscopic surgeon in certain patients. The pie-crusting technique of the medial collateral ligament which can be done percutaneously to open up a tight posteromedial compartment would be a good option in such patients. Here, the authors introduce a useful alternative portal for approaching the posterior horn of the medial meniscus, the under-meniscal portal. The under-meniscal portal is located under the menisci and can be placed safely and easily without any complication. It is also helpful for approaching the unstable underside of the horizontal tear in the anterior horn of the lateral meniscus. The authors suggest the under-meniscal portal as a good alternative portal for managing challenging lesions in the posterior horn of the medial meniscus and the anterior horn of the lateral meniscus.     

关节镜下全内缝合法修补内侧半月板后角损伤

目的:探讨内侧半月板后角损伤的关节镜下全内修补方法及其临床疗效。方法:自2002年4月~2005年4月间在本院进行前交叉韧带损伤合并内侧半月板后角损伤治疗的患者89例。对其中85例患者应用全内缝合方法手术,经两个后内入路配合髁间窝入路,利用缝合钩修补损伤半月板;同时选择绳肌腱、自体或异体骨-腱-骨移植物重建受损前交叉韧带。结果:可随访者75例(84·3%),随访5~41个月,平均20·2个月。随访采用主观症状检查、临床查体、2次关节镜手术复查(25例)及MRI复查(21例)等。随访到的75例患者的主观症状及临床查体结果均正常,其中25例患者经2次关节镜手术复查结果均为全部愈合;经MRI复查的21例患者中,18例完全愈合,3例部分愈合。结论:关节镜下全内缝合方法是修补内侧半月板后角损伤的理想方法,术后疗效好。     

Meniscal tears on knee arthrography: Patterns of arthrographic abnormalities

The presence or absence of a meniscal tear was established in 340 out of 475 consecutive patients who had double contrast knee arthrograms. The accuracy in these 340 cases was 95% for both the medial and lateral menisci although the specificity for lateral tears was only 0.64. Analysis of the pattern of arthrographic abnormalities revealed that both medial and lateral tears usually involved the posterior horn of the meniscus. Posterior horn abnormalities rarely caused a false positive diagnosis of a meniscal tear. In contrast, isolated blunting of the anterior horn of either the lateral or medial meniscus was an unreliable sign of a tear and accounted for many of the false positive diagnoses. It is concluded that careful attention to the posterior horn of each meniscus is essential for accurate arthrographic diagnosis of a meniscal tear.     

Wrisberg variant of the discoid lateral meniscus with flipped meniscal fragments simulating bucket-handle tear: MRI and arthroscopic correlation

An MRI diagnosis of the Wrisberg variant discoid lateral meniscus should be considered in patients presenting with an anteriorly flipped posterior horn fragment without a definable peripheral rim. We present four cases discovered on arthroscopy that were thought to resemble bucket-handle tears on preoperative MRI. Posterior hypermobility poses a surgical challenge as excessive debridement without careful attention to underlying meniscal morphology may lead to further instability. Although this diagnosis can be difficult to make on MRI, alerting the orthopedic surgeon preoperatively may influence repair technique and meniscus conservation.     

Meniscus tears that can be left in situ, with or without trephination or synovial abrasion to stimulate healing

To determine which meniscus tears to leave in situ, the clinician must know whether the meniscus tear is degenerative or nondegenerative, stable or unstable, in an anterior cruciate ligament (ACL)-stable or ACL-unstable knee, and whether it is in the medial or lateral compartment. Symptomatic medial meniscus tears in ACL-intact knees are almost always degenerative in nature and should be removed. Generally, the only type of medial meniscus that can be left in situ is a peripheral, vertical, nondegenerative tear, but these tears are not displaceable, are asymptomatic, and are usually seen in a patient with an ACL tear. In the lateral compartment, most tears can be left in situ and the only tears that need to be repaired are displaceable tears that extend anterior to the popliteus tendon. Although many meniscus repair techniques and fixation devices are available, all factors related to healing and stability should be considered to determine treatment.     

Arthroscopic pullout repair of posterior root tear of the medial meniscus: the anterior approach using medial collateral ligament pie-crusting release

Posterior root tears of the medial meniscus are frequently encountered and should be repaired if possible to prevent osteoarthritis of the medial compartment. Various surgical techniques have been proposed to repair posterior root tears. The anterior arthroscopic approach can cause an iatrogenic chondral injury due to the narrow medial joint space. The posterior approaches might be technically unfamiliar to many surgeons because they require the establishment of a posteromedial or trans-septal portal. This paper describes the medial collateral ligament pie-crusting release technique for arthroscopic double transosseous pullout repair of posterior root tears of the medial meniscus through the anterior approach to provide the good visualization of the footprint and sufficient working space.     

Meniscal bucket handle tears: a retrospective study of arthroscopy and the relation to MRI

In this study, we aim to evaluate the arthroscopic findings of meniscal bucket handle tears and to correlate them with the proposed MR imaging signs of meniscal bucket handle tears suggested in the literature. Thirty-six patients who had a diagnosis of bucket handle tear in arthroscopy, in either medial or lateral meniscus, were included in our study (32 males and 4 females). Meniscal tears were evaluated in arthroscopy according to Dandys classification. The MRIs were retrospectively analyzed regarding the following findings: absence of bow tie sign, presence of double posterior cruciate ligament (PCL) sign, double anterior horn sign, flipped meniscus sign, disproportional posterior horn sign, and fragment within the intercondylar region. Locked types I and II fragment of medial meniscus and half-length, whole-width and whole length–half-width fragment of lateral meniscus in arthroscopy were basically correlated with fragment within the intercondylar notch and absent bow tie signs in MRI. We did not find the double PCL sign in any of the patients with a lateral meniscal bucket handle tear. The most common signs in MR images of meniscal bucket handle tears were the fragment in the notch sign and the absent bow tie sign. They were observed with equal frequency of 88.8%. The presence of double PCL sign, double anterior horn sign, flipped meniscus sign, disproportional posterior horn sign were less common (41.66, 33, 25, and 27.7%, respectively). We conclude that the presence of at least two of the six MRI signs should be regarded as highly suggestive for bucket handle tears of menisci.     

The flipped meniscus sign

Meniscal fragments may be difficult to detect on magnetic resonance (MR) imaging and yet are clinically significant. This paper describes and illustrates the MR appearance of an easily overlooked meniscal fragment. Ten knees, each appearing to show an abnormally large anterior meniscal horn (8 mm or more in height) were prospectively identified on MR images. In each case demonstrable large tears of the ipsilateral posterior horns were present (same meniscus as had large anterior horns). The lateral meniscus was involved in nine cases and the medial in one. Two of the ten patients imaged had surgically proven bucket-handle meniscal tears as well as meniscal fragments overlying the ipsilateral anterior horn. In one case previous MR imaging at our institution had demonstrated the affected anterior horn to be of normal caliber. The striking MR appearance of an abnormally enlarged anterior meniscal horn in association with a tear of the ipsilateral posterior horn suggests the presence of a meniscal fragment or of a posteriorly detached bucket-handle tear of the posterior horn of the meniscus.Presented at the Fifteenth Annual Skeletal Symposium of the Hospital of the University of Pennsylvania at Sun Valley, Idaho, USA, on 3 March 1992     

Abnormal superior popliteomeniscal fascicle and posterior pericapsular edema: indirect MR imaging signs of a lateral meniscal tear

OBJECTIVE. Because MR diagnosis of lateral meniscal tears can be difficult, indirect signs may be useful when a tear is suspected. We studied whether an abnormality of the superior popliteomeniscal fascicle or pericapsular edema was associated with lateral meniscal tears and thus may be an indirect MR imaging sign of a lateral meniscal tear. MATERIALS AND METHODS. We identified 59 consecutive patients who underwent both knee MR imaging examinations and knee arthroscopy. Thirty patients had lateral meniscal tears, and 29 had intact lateral menisci. We reviewed paired sagittal proton density- and T2-weighted MR images from these 59 patients for abnormal superior popliteomeniscal fascicles and edema surrounding the posterolateral capsule. RESULTS. The superior popliteomeniscal fascicles were abnormal in nine of the 30 patients with torn lateral menisci but were normal in all 29 patients with intact menisci (p = 0.001). Abnormal fascicles were apparent only when the lateral meniscal tear involved the posterior horn. Posterior pericapsular edema was seen in 10 patients with a torn posterior horn and in one patient with an anterior horn tear of the lateral meniscus, but in only two patients with intact menisci (p = 0.006). CONCLUSION. The presence of superior popliteomeniscal fascicle abnormalities and of posterior pericapsular edema is significantly associated with a tear of the lateral meniscus, most commonly in the posterior horn. Noting the presence of these findings may help improve the accuracy of MR diagnosis of lateral meniscal tears.     

Magnetic resonance diagnosis of meniscal tears in patients with acute anterior cruciate ligament tears

OBJECTIVE: To evaluate the accuracy of magnetic resonance imaging in the diagnosis of meniscal tear in patients with acute anterior cruciate ligament tears. METHODS: Magnetic resonance images obtained from 41 patients imaged within 6 weeks of injury who had acute anterior cruciate ligament tears identified at arthroscopy were retrospectively reviewed for meniscal tear. RESULTS: With MR imaging the sensitivity, specificity and accuracy for diagnosing meniscal tears in the presence of acute anterior cruciate ligament tears were 71%, 93%, and 88%; for the lateral meniscal tears were 57%, 100% and 85%; and for the medial meniscal tears were 100%, 88%, 90%. All false negative cases (n = 6) involved the posterior horn of the lateral meniscus. CONCLUSION: In the presence of acute anterior cruciate ligament tears, MRI imaging has relatively low sensitivity for detecting meniscal tears due to missed tears in the lateral meniscus.     

Bony morphology of the knee and non-traumatic meniscal tears: Is there a role for meniscal impingement?

Objective

Meniscal tears are an important cause of morbidity. The aim of this study was to examine the relationship between non-traumatic meniscal tears and the intrinsic bony morphology of the knee.

Methods

A retrospective analysis of 160 knee MRI scans in 150 patients was carried out who met the following criteria: (a) age between 20 and 45 years, (b) no history of knee trauma, surgery, infection, metabolic bone disease, and (c) no collateral or cruciate ligamentous injury. The medial tibial slope (MTS), lateral tibial slope (LTS), medial tibial plateau depth (MTPD), and medial and lateral femoral condylar offset ratios were calculated. The anterior horn, body, and posterior horn of the menisci were graded as 0 (no tear), 1 and 2 (degenerative changes), or 3 (definitive tear). One-way ANOVA and linear regression was used for statistical analysis.

Results

In patients with grade 3 tears of the posterior horn of the medial meniscus, there was a significant association with shallower MTS (p?<?0.05), smaller medial femoral offset ratio (p?<?0.05) and smaller lateral femoral offset ratio (p?<?0.05). Patients with grade 3 tears of anterior horn of the lateral meniscus had a significant association with shallower LTS (p?<?0.05). No significant association was seen between MTPD and meniscal tears.

Conclusions

Our results suggest an association between bony morphology of the knee and non-traumatic meniscal tears. Shallower MTS and LTS may result in impingement of posterior horn of medial meniscus and anterior horn of lateral meniscus, respectively. Future kinematic studies will be needed to help confirm our findings.     

The clinical significance of anterior horn meniscal tears diagnosed on magnetic resonance images

We assessed the accuracy of magnetic resonance imaging in detecting clinically significant lesions of the anterior horn of the meniscus by reviewing 947 consecutive knee magnetic resonance imaging reports. Of these, 76 (8%) indicated a tear of the anterior horn of the medial or lateral meniscus. Thirty-one of these 76 patients underwent a subsequent arthroscopic examination, and their operative reports were reviewed. The 45 patients who were not examined arthroscopically were contacted and interviewed for clinical follow-up. Among the 31 patients who underwent arthroscopic examination, 8 anterior horn tears were noted in the predicted area (26% true-positive results), 23 patients had intact anterior horns (74% false-positive results), and 18 had normal intact menisci in all zones. Of the 45 patients who did not undergo arthroscopic surgery, 6 had isolated anterior horn tears reported on magnetic resonance imaging, and 5 of the 6 were asymptomatic at follow-up. The other 39 patients had multiple pathologic conditions noted on the magnetic resonance imaging report and continued to report knee pain at the follow-up interview. Increased signal intensity at the anterior horn of the meniscus seen on magnetic resonance imaging commonly does not represent a clinically significant lesion. We recommend correlation with the physical examination when interpreting this "positive" finding on knee magnetic resonance imaging examinations.     

Healing results of meniscal tears left in situ during anterior cruciate ligament reconstruction: a review of clinical studies

The presence of peripheral meniscal tears is common at the time of anterior cruciate ligament (ACL) reconstruction. Techniques to preserve the maximum amount of meniscal tissue include “non operative” management (tear left alone, without repair or removal), meniscus repair, partial meniscectomy. There is a lack of consensus guidelines about the management of peripheral stable meniscal tears. When to remove, let alone or repair? We performed an evidence-based review of the outcomes of stable meniscal tears left in situ during ACL surgery, in order to assess the effectiveness of this popular procedure. Clinical and anatomical results (arthrography or second look arthroscopy) were analyzed. Our literature search yielded ten relevant studies (9 level IV, 1 level III). The mean time of follow-up was 16 months. Pain or mechanical symptoms related to the medial tibiofemoral joint were reported in 0–66% of cases. Subsequent medial meniscectomy or repair were performed in 0–33% of cases. Pain or mechanical symptoms related to the lateral tibiofemoral joint were reported in 0–18% cases. Subsequent lateral meniscectomy or repair were performed in 0–22% cases. A complete healing occurred in 50–61% cases for the medial meniscus and in 55–74% cases for the lateral meniscus. No definite conclusion can be made with regard to these results. The conservative approach is more effective for lateral menisci. The rate of bad results for the medial meniscus remains high when a conservative treatment is used. For the medial meniscus, repair of stable peripheral tears may be always indicated to decrease the risk of postoperative pain or subsequent meniscectomy.