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.     

Sartorial branch of the saphenous nerve in relation to a medial knee ligament repair or reconstruction

Surgical approaches to repair or reconstruct the medial knee structures note caution to avoid the sartorial branch of saphenous nerve. However, the approximate area of potential iatrogenic nerve injury has not been previously described in relation to landmarks for a medial knee reconstruction. The purpose of this study was to define the course of the sartorial branch of the saphenous nerve in relation to the superficial medial collateral ligament. A total of ten non-paired, fresh-frozen cadaveric knees, with no evidence of prior injury or disease were utilized. Dissection to identify the medial knee structures was performed. The sartorial branch of the saphenous nerve was identified in all specimens. The perpendicular distance from the anterior border of the superficial medial collateral ligament 2 cm distal from the joint line to the sartorial branch of the saphenous nerve was 4.8 ± 0.9 cm. The distance from the anterior border of the superficial medial collateral ligament to the sartorial branch of the saphenous nerve decreased as the distance was increased distally with a mean distance of 4 cm (4.1 ± 0.8 cm) distal from the joint line and 6 cm (3.8 ± 0.8 cm) distal from the joint line. We have characterized the surgically relevant landmark anatomy of the sartorial branch of the saphenous nerve in regards to performing a repair or reconstruction of the medial knee structures. Familiarity with these anatomic landmarks and associated distances from the sartorial branch of the saphenous nerve, we can assess the potential area of vulnerability to this nerve branch intraoperatively.     

A pull out suture for transection of the posterior horn of the medial meniscus: using a posterior trans-septal portal

A transection (root tear or complete radial tear) injury of the medial meniscus posterior horn is not rare in the oriental area and needs to be repaired to restore the hoop tension and to reduce the extruded meniscus, which leads to osteoarthritis of the knee. In cases with transection of the medial meniscus posterior horn, the meniscus can be repaired by a pull out suture technique. However, it is difficult to manipulate a suture hook and drill a tibial tunnel in the narrow medial joint space using the traditional anterior arthroscopic technique. This article describes a new pull out suture technique for transection of the medial meniscus posterior horn using a posterior trans-septal portal that provides a safe and wide field of vision. The handling of the suture hook and a guide may reduce the possibility of a chondral or meniscal injury.     

Displaced avulsion fracture of medial meniscus posterior horn through the intercondylar notch in the patient without combined ligamentous injuries

Avulsion fractures of the posterior horn of the medial meniscus are uncommon and must be differentiated from a loose body. The authors present a displaced avulsion fracture of the medial meniscus posterior horn through the intercondylar notch into the anteromedial compartment of the knee, which was treated by arthroscopic reduction and internal fixation using pull-out suture technique.     

半月板大桶柄样撕裂的关节镜下联合修补技术

目的:介绍关节镜下自内向外缝合技术联合全内缝合技术修补半月板的手术方式(联合修补技术),探讨修补半月板大桶柄样撕裂的安全、可靠方法。方法:2002年5月~2006年1月,采用关节镜下联合修补技术修补93例患者的96个半月板大桶柄样撕裂,均累及半月板后角至前角与体部交界处(前体部)区域。手术适应症:红-红区及红-白区损伤、具备可复位性、半月板组织无复合撕裂及明显变性、前十字韧带(ACL)完整或同时重建。手术技术:撕裂的后角与体部交界处(后体部)至中、前1/3区域采用标准的自内向外缝合技术:在半月板上、下表面交错进行垂直褥式缝合,膝后内侧或后外侧作辅助安全切口保护血管神经,伸膝位将缝线在关节囊浅层打结固定;撕裂的后部区域采用全关节内缝合技术:经两个后内侧或后外侧入路在关节内完成垂直褥式缝合、打结及剪线。单纯的红-白区撕裂修补后局部植入血凝块促进愈合,合并前十字韧带损伤者同时行韧带重建手术。术后对93例患者中的49例共51个半月板进行了平均20·1个月(9·2个月~54·2个月)的随访。随访时均进行了临床评估,包括交锁、积液、关节间隙压痛、McMurray试验。随访结果显示:49例患者中,无症状者46例(93·9%),关节间隙压痛者2例(4·1%),交锁复发1例(2%)。51个半月板中的44个(86·3%)经MRI复查,结果为:30个(68·2%)完全愈合,13个(29·5%)部分愈合,1个(2·3%)不愈合。38例患者共40个半月板(78·4%)经过二次手术探查,完全愈合者36个(90%),部分愈合者2个(5%),不愈合行半月板切除者2个(5%)。膝关节活动度检查显示3例伸膝受限>10°。结论:对于发生在红-红区或红-白区的大型半月板撕裂,采用自内向外与全关节内两种缝合技术可以保证撕裂的全长区域获得有效、稳定的修补,并且与ACL重建同期进行,可以获得很好的主、客观临床疗效。联合修补技术是安全、可靠的半月板大桶柄样撕裂的修补方法。     

Roentgen anatomy of the posterior horn of the lateral meniscus.

The roentgen anatomy of the posterior horn of the lateral meniscus of the knee is presented with particular attention to the relationships between the popliteus tendon, joint capsule and meniscus. The popliteus tendon creates a tunnel as it passes obliquely through the posterior half of the meniscus creating two walls (medial and lateral) and a roof (superior attachment) and a floor (inferior attachment). The boundaries are readily visible on the double-contrast knee arthrogram. Familiarity with these relationships aids in the diagnosis of meniscal injuries.     

Tibial meniscal dynamics using three-dimensional reconstruction of magnetic resonance images.

The human knee joint represents a complex biomechanical system of which the menisci are an integral component. At present, little data exists describing the meniscal kinematics of the intact knee. Accordingly, a three-dimensional reconstruction magnetic resonance image model was used to explore this issue. Five fresh cadaveric knees were examined by magnetic resonance imaging throughout a full range of motion at 10 degrees intervals. Computer three-dimensional images of the menisci were generated and evaluated for anteroposterior excursion and deformation. During flexion, the posterior excursion of the medial meniscus was 5.1 mm, while that of the lateral meniscus was 11.2 mm. The anterior horn segments were shown to be more mobile than the posterior horn segments bilaterally. Prior limitations of meniscal kinematic assessment may be overcome with advanced imaging techniques such as magnetic resonance imaging and three-dimensional reconstruction. The menisci are highly mobile and easily deformed structures within the intact, cadaveric knee. This imaging technique may prove useful in the elucidation of meniscal dynamics. In the future, similar techniques may be applied clinically to aid in the diagnosis of joint dysfunction.     

关节镜下膝关节腘肌腱重建的实验研究

目的:进一步研究膝关节后外复合体(posterolateral complex,PLC)与腘肌复合体的解剖特点,设计关节镜下重建腘肌腱的手术方法.方法:通过10例成人膝关节尸体标本进行两部分研究,每部分各取5例标本:第一部分进行大体解剖研究,对腘肌复合体(包括腘肌腱、肌腹、股骨附着点、肌腱-肌腹交界区)的解剖特点以及周围相邻解剖结构(包括胫骨平台、外侧半月板后角、后交叉韧带、胭腓韧带、血管)进行观察和测量.第二部分进行关节镜下手术重建技术的流程设计.设计显露腘肌腱的股骨附着点和肌腱-肌腹交界点的关节镜入路以及股骨和胫骨隧道的定位与制备方法,引入移植物并固定,完成腘肌腱的重建.结果:第一部分:腘肌腱的股骨附着点位于滑膜反折区,属滑膜外结构;止于股骨的腘肌腱沟的最近端,与关节软骨边缘紧邻,与外侧副韧带股骨附着点中心相距1.5～1.6cm.腘肌腱走行于腘肌腱浅沟内、肌腱-肌腹交界点位于胫骨后外侧平台的内、外中线与关节软骨面远侧1.0cm线的交点上,内侧距离后交叉韧带外侧边缘1.2～2.0cm、外侧与上胫腓关节的内侧缘紧邻.第二部分:进行膝关节镜下手术操作.采用前外入路及外侧辅助关节镜入路切除腘肌腱近端附着点周围滑膜反折,显露整个附着区,并利用克氏针确定中心点,自外向内制备股骨隧道.通过后外、后内及穿后间隔关节镜入路,沿腘肌腱走行局部切开与后关节囊的结合部,显露肌腱-肌腹交界点,并利用前交叉韧带重建胫骨导向器定位,自Gerdy结节向该交界点制备前后方向胫骨骨隧道.将移植物引入两隧道,并用挤压螺钉固定.5例标本手术均获成功,移植物可有效控制外旋稳定性.结论:根据解剖研究确定腘肌腱远近端的定位标志,通过关节镜技术进行显露及定位,在关节镜下完成腘肌腱的重建手术具有可行性.     

The distal semimembranosus complex: normal MR anatomy,variants, biomechanics and pathology

OBJECTIVE: To describe the normal MR anatomy and variations of the distal semimembranosus tendinous arms and the posterior oblique ligament as seen in the three orthogonal planes, to review the biomechanics of this complex and to illustrate pathologic examples. RESULTS AND CONCLUSION: The distal semimembranosus tendon divides into five tendinous arms named the anterior, direct, capsular, inferior and the oblique popliteal ligament. These arms intertwine with the branches of the posterior oblique ligament in the posterior medial aspect of the knee, providing stability. This tendon-ligamentous complex also acts synergistically with the popliteus muscle and actively pulls the posterior horn of the medial meniscus during knee flexion. Pathologic conditions involving this complex include complete and partial tears, insertional tendinosis, avulsion fractures and bursitis.     

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。     

Transverse ligament and its effect on meniscal motion. Correlation of kinematic MR imaging and anatomic sections.

RATIONALE AND OBJECTIVES: To evaluate the effect of the transverse ligament on translation of the menisci. METHODS: Six cadaveric knees were examined by MR imaging inside a positioning device before and after transecting the transverse ligament. The knees were examined at various positions: extension, 30 degrees of flexion, 60 degrees of flexion, and full flexion. Sagittal T1-weighted spin-echo images were generated at each knee position and evaluated for statistical differences with regard to anterior-posterior meniscal excursion. RESULTS: Statistically significant differences in meniscal excursion were found before and after transsecting the transverse ligament for anterior-posterior meniscal motion of the anterior horn of the medial meniscus at 30 degrees of knee flexion. No such significant differences were found, however, at 60 degrees of flexion and full flexion in anterior-posterior meniscal excursion of the anterior or posterior horn of either meniscus before and after transsecting the transverse ligament. CONCLUSIONS: The transverse ligament has a restricting effect on anterior-posterior excursion of the anterior horn of the medial meniscus at lower degrees of knee flexion.     

Pitfalls in MR imaging of the knee

Discrepancies between the findings of magnetic resonance (MR) imaging and those of arthroscopy were reviewed retrospectively in 52 knee examinations. Some of the discrepancies between MR imaging and arthroscopy were caused by errors in interpretation of MR images due to normal structures that mimicked meniscal tears. The transverse ligament and the lateral inferior genicular artery can produce the appearance of tears in the anterior horns of the medial and lateral menisci, respectively. The popliteus tendon may be mistaken for a tear in the posterior horn of the lateral meniscus. The normal concavity at the outer edge of the meniscus can create a volume-averaging artifact, which mimics a horizontal tear in the meniscus. Tears of the meniscus and separations of the meniscus from the joint capsule were not seen or were underestimated when the tears were oriented parallel to the plane of the image. An awareness of these pitfalls may improve the accuracy of the interpretation of MR images of the knee.     

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.     

Semimembranosus tendon viewed through an isolated medial meniscus capsular avulsion: a case report

The semimembranosus is a key component of the complex anatomy of the posteromedial knee. Its multiple distal insertions are intimately associated with the posterior capsule, medial meniscus, and posterior oblique ligament. Visualization of the semimembranosus is possible during arthroscopy when a significant posteromedial capsular injury is present. This typically occurs only in the setting of significant trauma, with associated injury to the other posteromedial knee structures. We present a case of an isolated medial meniscus capsular avulsion, with minimal trauma, in which the semimembranosus tendon is clearly visualized during arthroscopic meniscal repair.     

The popliteus tendon provides a safe and reliable location for all-inside meniscal repair device placement

Purpose

Repairs of the posterior horn of the lateral meniscus can be technically challenging. In contrast to medial meniscus repairs, the capsule around the posterior segment attachment of the lateral meniscus is quite thin. This study evaluates the clinical results of an arthroscopic all-inside repair technique for unstable, vertical, lateral meniscus tears, using a suture repair placed directly into the popliteus tendon.

Methods

A retrospective analysis of prospectively collected data from the SANTI database was performed. All patients who had undergone combined ACL reconstruction with lateral meniscus all-inside repair, using sutures placed in the popliteus tendon, between 2011 and 2015, were included. Patients were reviewed clinically at 1 and 2 years’ follow-up. At final follow-up, all patients were contacted to identify if they underwent further surgery or had knee pain, locking or effusion. Symptomatic patients were recalled for clinical evaluation by a physician and Magnetic Resonance Imaging of the knee. Operative notes for those undergoing further surgery were reviewed and rates and type of re-operation, including for failed lateral meniscal repair were recorded.

Results

Two hundred patients (mean age 28.6?±?10.2 years) with a mean follow-up of 45.5?±?12.8 months (range 24.7–75.2) were included. The mean Subjective International Knee Documentation Committee (IKDC) at final follow-up was 85.0?±?11.3. The post-operative mean side-to-side laxity measured at 1 year was 0.6?±?1.0 mm. Twenty-six patients underwent re-operation (13%) at a mean follow-up of 14.8?±?7.8 months. The ACL graft rupture rate was 5.0%. Other causes for re-operation included medial meniscus tear (2.5%), cyclops lesion (1.5%) and septic arthritis (0.5%). The lateral meniscus repair failure rate was 3.5%. No specific complications relating to placement of sutures in the popliteus tendon were identified.

Conclusion

Arthroscopic all-inside repair of unstable, vertical, lateral meniscus tears using a suture placed in the popliteus tendon is a safe technique. It is associated with a very low failure rate with no specific complications.

Level of evidence

Level IV.

     

Meniscofemoral ligaments: patterns of tears and pseudotears of the menisci using cadaveric and clinical material

Purpose The purpose of the study was to determine the different types of pseudotears of the posterior horn of the lateral meniscus caused by the nearby meniscofemoral ligaments (MFLs), and to correlate the presence of these ligaments with patterns of meniscal tear. Design Retrospective clinical study with patients and prospective observatory study with cadaveric material. Patients Magnetic resonance imaging studies of the knee in 49 patients who had subsequent arthroscopy of the knee performed over a 1-year period at a single institution were reviewed by two readers in consensus for the presence and morphology of the MFLs of Humphry (LH) and Wrisberg (LW). Ten cadaveric knee specimens were used for MRI, anatomic, and histologic study. Results The LH was present in 55% of patients, the LW in 94%, and both were present in 44.9%. The thickness of the LH and LW ranged from 1–3 mm (mean 1.9, SD 0.61), and from 1–3.8 mm (mean 1.8, SD 0.65) respectively (p > 0.05). A pseudotear in the posterior horn of the lateral meniscus was present in 63% of patients. In 13% the pseudotear was vertically oriented, and in 87% the pseudotear had an anterosuperior to posteroinferior orientation, ranging from 37 to 87°. There was no association between the presence of one or both MFLs and the occurrence of medial or lateral meniscal tears (p > 0.05). Conclusion Meniscofemoral ligaments are frequent anatomical structures that are found in the majority of knees with MRI. They commonly cause a pseudotear of the posterior horn of the lateral meniscus that can be simple, double, or complex in appearance, with vertical or anterosuperior to posteroinferior orientation.     

MR imaging of the knee: pseudotear of the lateral meniscus caused by the meniscofemoral ligament

Sagittal MR images of the knee often show a linear band of increased signal in the medial aspect of the posterior horn of the lateral meniscus that can be confused with a meniscal tear. This pseudotear is due to the meniscal insertion of the meniscofemoral ligament. To study the normal appearance of the medial aspect of the posterior horn of the lateral meniscus, we analyzed 109 MR examinations and correlated the findings with the results of arthroscopy. The meniscofemoral ligament was visualized in 54 cases (50%), and in 42 cases (39%) it caused the appearance of a pseudotear on sagittal images. The pseudotear had one of two orientations. The most common (35/42) was an oblique orientation coursing from the superior surface posteriorly and inferiorly. The other (7/42) was a more vertical orientation parallel to the base of the meniscus. Knowledge of the characteristic location and orientation of the meniscofemoral ligament should help to distinguish it from a true meniscal tear on MR images.     

Pullout failure strength of the posterior horn of the medial meniscus with root ligament tear

Purpose

To evaluate the reparability of the posterior horn of the medial meniscus with root ligament tear by measuring the actual pullout failure strength of a simple vertical suture of an arthroscopic subtotal meniscectomized posterior horn of the medial meniscus.

Methods

From November 2009 to May 2010, nine posterior horns of the medial meniscus specimens were collected from arthroscopic subtotal meniscectomy performed as a treatment for root ligament rupture of the posterior horn of the medial meniscus. Simple vertical sutures were performed on the specimens, and pullout failure load was tested with a biaxial servohydraulic testing machine (Model 8874; Instron Corp., Norwood, MA, USA). The degree of degeneration, extrusion, and medial displacement of the medial meniscus were evaluated with magnetic resonance imaging (MRI). The Kellgren–Lawrence classification was used in standing plain radiography, and mechanical alignment was measured using orthoroentgenography. Tear morphology was classified into ligament proper type or meniscoligamentous junctional type according to the site of the torn root ligament of the posterior horn of the medial meniscus during arthroscopy.

Results

The mean pullout failure strength of the posterior horn of the medial meniscus was 71.6 ± 23.2 N (range, 41.4–107.7 N). The degree of degeneration of the posterior horn of the medial meniscus on MRI showed statistically significant correlation with pullout failure strength and Kellgren–Lawrence classification. Pullout failure strength showed correlation with mechanical alignment and Kellgren–Lawrence classification (P < 0.05).

Conclusions

The measurement of pullout failure strength of the posterior horn of the medial meniscus with root ligament tear showed a degree of repairability. The degree of degeneration of the posterior horn of the medial meniscus on MRI showed a significant correlation with the pullout failure strength. The pullout failure strength was also not only correlated with the degree of degeneration of the posterior horn of the medial meniscus, but also with mechanical alignment and Kellgren-Lawrence classification, which represent bony degenerative change.     

The arrow versus horizontal suture in arthroscopic meniscus repair A prospective randomized study with arthroscopic evaluation

In a prospectively randomized study including 68 patients, the results of inside-out horizontal meniscus suturing were compared to meniscus repair using the meniscus arrow. 96% of the patients underwent re-arthroscopy after 3–4 months. Only lesions in the red/red or red/white areas were included. Patients were treated with a hinged brace for 9 weeks. 30 patients had an isolated bucket-handle lesion. In 19 cases the repair was done in conjunction with an ACL reconstruction and in 19 cases the repair was performed in an ACL-insufficient knee. The two groups were comparable. Operating time in the arrow group was one half that of the suture group. Of 65 re-arthroscopies, 91% of the patients had healed or partially healed in the arrow group compared to 75% in the suture group (P = 0.11). In only 50% of the non-healed cases was this clinically suspected prior to control arthroscopy. The difference between healing in ACL-reconstructed and ACL-insufficient knees was not significant. Two patients in the suture group had a deep infection. There were no serious neurovascular injuries. Five patients in the suture group and two patients in the arrow group had symptoms in the saphenous nerve area. All patients had some synovial irritation at control arthroscopy but no severe reactions to suture or arrows were seen. Short-term results with meniscus arrows, based on healing and evaluated by second-look arthroscopy, seem promising. Received: 20 May 1998 Accepted: 15 April 1999     

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.