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Meniscus Root Repair
ARTICLE IN PRESS
Meniscus Root Repair Douglas J. Navasartian, MD, MS,* and Thomas M. DeBerardino, MDz,1 It has long been recognized that injuries to the menisci have a significantly detrimental effect on knee kinematics and can cause pathology within the knee joint. The consequences of these tears can lead to progressive degenerative changes of the chondral surfaces in the knee. Because of the deleterious sequelae of meniscal root tears, identification of these tears and a means of potential surgical treatment are paramount. The following is a discussion of meniscal root tears and the surgical techniques that can be utilized in operative treatment. Oper Tech Sports Med 00:1-8 © 2018 Elsevier Inc. All rights reserved.
KEYWORDS Meniscal root tear, meniscal root tear repair
Introduction
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t has been demonstrated as early as 1948 that mensicectomy leads to damage of the knee articular cartilage.1 A key function of the meniscus is to dissipate hoop stress.2 Allaire et al showed that disruption of the posterior root of the medial meniscus significantly decreases the ability of the meniscus to dissipate this stress.3 The effect of such a tear was shown to result in contact pressures that approximated that of total medial mensicectomy.3 Interestingly, the study by Allaire et al also revealed that repair of the posterior root of the medial meniscus resulted in restoration of the ability of the meniscus to dissipate contact pressures.3 Given that tear patterns of the meniscal root vary, a means of classification can assist in uniformity in the description of tears across various providers and potentially aid in the specificity of communication regarding these injuries. A classification system of meniscal root tears was developed by LaPrade et al (Fig. 1).4 This classification system uses meniscal root tear morphology as a means of separating out 5 different patterns of tears. The first type is a partial tear and is considered stable. The second is a tear within 9 mm of the root attachment to the tibia and is complete. The third type *Orthopaedic Sports Medicine, The Combined Baylor College of Medicine and San Antonio Orthopaedic Group, Texas Sports Medicine Fellowship, San Antonio and Houston, TX. z Burkhart Research Institute for Orthopaedics (BRIO) and the Sports Institute at TSAOG Orthopaedics, San Antonio, TX. Address reprint requests to Thomas M. DeBerardino, MD, 635 Elizabeth Rd, San Antonio, TX 78209-6134. E-mail: [email protected] 1 The name of the institution where the work reported was done (“From...”) From The Sports Institute at the San Antonio Orthopaedic Group.
https://doi.org/10.1053/j.otsm.2018.10.004 1060-1872/© 2018 Elsevier Inc. All rights reserved.
is a complete detachment of a bucket handle tear extending through, and including, the meniscal root. The fourth type is a complex oblique tear that extends into the meniscal root. The fifth type is an avulsion fracture of the root attachment. The most common of these types in the population investigated in their study was the type 2 morphologic pattern, which was seen in 67.6% of the subjects.4 Because of the morbidity that can be caused by meniscal root tears, accurate diagnosis is imperative. The diagnosis of meniscal root tears however can be difficult. As reviewed by Bhatia et al and Petersen et al, there can be considerable variability in regard to how meniscal tears present clinically.5,6 These discussions note the original research of Lee et al and Seil et al.5-8 In a study performed by Lee et al, the clinical manifestations of 21 posterior root tears of the medial meniscus were described.7 Only 9.5% reported a “giving way” event, and only 14.3 % described locking of the knee. Potential findings noted on physical examination were pain on full flexion, joint line tenderness, positive McMurray's, and knee effusion. Of these findings, pain on full flexion was the most commonly observed; however, even this was only demonstrated in approximately two-thirds of patients.7 Seil et al noted that the application of a varus stress while simultaneously palpating the anteromedial meniscus could elicit meniscus extrusion, and in this manner could aid in the diagnosis of root avulsions of the posterior horn of the medial meniscus.8 Multiple articles have also discussed the clinical manifestations of meniscal root tears as delineated by the 2004 research by Bin et al.6-9 In this study, 100% of the knees with posteromedial meniscal root tears
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ARTICLE IN PRESS D.J. Navasartian and T.M. DeBerardino
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Figure 1 Illustration of the classification system of meniscal root tears based on tear morphology developed by LaPrade et al. Type I: partial tear, considered stable. Type 2: tear within 9 mm of the root attachment to the tibia, complete. Type 3: complete detachment of a bucket handle tear extending through, and including, the meniscal root. Type 4: complex oblique tear that extends into the meniscal root. Type 5: an avulsion fracture of the root attachment. The American Journal of Sports Medicine, Vol. 43, No. 2. DOI: 10.1177/0363546514559684. Copyright 2014 The Author (s). Reprinted under STM Guidelines.4
had a knee effusion.9 Although this finding is nonspecific, it was the most common clinical indicator of a meniscal root tear that was identified in the study.9 This is vastly different than the findings by Lee et al, which found that 14.3% of the patients had a knee effusion.7 Such variability in patient presentation underlines the challenges that can be encountered when diagnosing meniscal root tears clinically. Magnetic resonance imaging (MRI) has the ability to delineate the anatomy of the meniscal roots in detail.10 Furthermore, MRI has been shown to be helpful in the diagnosis of the presence of meniscal root tears.11 In a study by Lee et al, MRI findings of medial meniscal root tears were evaluated.12 In this study, although the overall diagnostic capabilities of the MRI to determine the presence of a tear posterior horn medial meniscus root were high, all complex tears of the posterior horn medial meniscus root were misdiagnosed as radial tears. The authors note however that this inability to differentiate the 2 would not affect the ultimate surgical plan of care.12
Treatment The treatments for meniscal root tears can be either operative or nonoperative. The decision as to proceed with nonoperative treatment depends on specific patient characteristics. It has been suggested that patients who are poor surgical candidates or patients with significant degenerative changes should undergo a trial of nonoperative management, and that these treatment measures can extend from bracing, to activity modification, to medications.5 In a study by Krych et al, a retrospective review of 52 patients who were treated nonoperatively for root tears of the posterior horn of the medial meniscus.13 The response of this population to nonoperative treatment was studied, as was their rate of conversion to total knee arthroplasty.13 It was found that 87% of patients failed nonoperative treatment, and that by conclusion of the study period, a total of 31% of patients underwent total knee arthroplasty.13 Given that meniscal root tears can lead to a significant increase in the stress experienced by the tibiofemoral joint (and therefore degenerative changes),
ARTICLE IN PRESS Meniscus Root Repair patients with already advanced degenerative changes should attempt conservative measures with symptomatic treatment before being considered for a total knee arthroplasty.3,5 When a patient is indicated for operative treatment, surgical options include partial meniscectomy or repair.5,14,15 It has been shown however that in the case of radial root tears in the posterior horn of the medial meniscus, although partial mensicectomy can be effective in relieving pain initially, it does not prevent degenerative changes in the knee.15 This is in contrast to the meniscal root repair, which has been noted to restore the hoop stress dissipation provided by the meniscus.3 Such restoration of hoop stress allowed by repair could help prevent the advancement of degenerative changes that would have been caused by either leaving the tear or by meniscectomy. A study done by Kim et al showed that arthroscopic repair of medial meniscal root tears resulted in less progression toward arthritic degeneration as well as better clinical outcomes when compared to partial meniscectomy.16 Determination of which patients should be considered for meniscal root repair is dependent on a number of factors. As discussed by Bhatia et al, younger patients without significant chondral damage who sustained a traumatic tear are ideal candidates for repair.5 In their review, an algorithm was suggested which favored acute tears being repaired, and chronic tears being repaired if there were not grade III or IV arthritis. If these patients did have these stages of degenerative changes, then symptomatic tears were treated with partial mensicectomy.5 A study done by LaPrade et al showed that patients similarly benefited from repair of posterior meniscal root tears regardless of the patients being younger or older than 50 years of age.17 This study also demonstrated similarly high patient satisfaction scores regardless of whether the repair was performed on the medial or lateral meniscus.17
Repair Repair of the meniscal root, whether medial or lateral, can be performed in a number of ways. These methods included transosseous repairs and repairs that use anchors.5,14 The literature regarding the surgical techniques of meniscal root repair is more readily found in regard to posterior meniscal root tears as opposed to anterior meniscal root tears, for which there is a relative scarcity of information.5 More recently, however, there been descriptions of similar techniques that can also be utilized for anterior meniscus root repair.18,19
Transosseous Repairs Transosseous repairs can be carried out using a bone bridge for suture fixation or through the use of bone tunnels that are used to shuttle sutures for eventual fixation of the sutures to the bone using a button or anchor.5,14 The use of a bony bridge for fixation after passage through transtibial tunnels has been described by a number of authors.20-22 An example
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Figure 2 Illustration of the fixation of the posteromedial meniscal root ossicle through the a posteromedial working portal using a Beath pin in what Raustol et al describe as being the appropriate trajectory. Note the suture preloaded through its eyelet. Reprinted with permission.20
of this is in the technique described by Raustol et al, fixation of a meniscal ossicle of the posteromedial meniscal root was performed through the use of a posteromedial working portal and a Beath pin (Fig. 2).20 The posteromedial portal was established, the meniscal ossicle reduced, the Beath pin (preloaded with suture through its eyelet) was passed from the posteromedial portal, through the fragment, and finally the pin advanced through the tibia until the came out the anteromedial aspect of the tibial cortex with the suture through its end.20 This was performed twice, making a mattress stitch through the fragment, and the suture ends were tied over a 10 mm bone bridge over the anteromedial tibia.20 Given that visualization of the meniscal root footprint can be challenging when multiple instruments are being used, Ahn et al made the use of a posterior trans-septal viewing portal and a posteromedial working portal to perform transosseous repair of the posterior horn of the medial meniscus with bone bridge fixation.22 In this technique, a posterolateral portal is a conduit for arthroscope entry into the posteromedial compartment through a trans-septal portal, which is used for viewing.22 A high posteromedial working portal is used to allow for passage of 3 mattress stitches, with a limb from each end of the stitch penetrating the meniscus in the anterior to posterior direction along the meniscal root. An anterior cruciate ligament guide was then used to introduce 2 pins from the anteromedial tibia to the position of the decorticated meniscal root footprint.22 These channels would then serve as retrieval tunnels for a wire suture passer to retrieve the sutures that were passed through the meniscus. The sutures are then retrieved and tied anteromedial tibial bone bridge.22 In the article, Ahn et al make analogy of the described technique being comparable to that of double row
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Figure 3 Arthroscopic view from the posterolateral portal looking through to the posteromedial compartment via the posterior transseptal portal. (A) The suture limbs being pulled through their respective bone tunnels. (B) The meniscal root after reduction, tensioning, and suture fixation over cortical bone bridge. Reprinted with permission.22
rotator cuff repair, in that through the use of the mattress sutures and 2 spaced transosseous tunnels, a larger surface area of meniscus to decorticated bone contact is created, and therefore a larger footprint for healing is made (Fig. 3).22 The technique described by LaPrade et al also uses 2 bone tunnels with the surface of the anteromedial tibia cortex serving as a point of fixation through use of a boney bridge; however, in this case, there is a different suture configuration and the sutures are first passed through a device (eg, button) before being fixated by means of a bony bridge to the cortex of the tibia.17 This study, as previously alluded to, also highlighted the efficacy of this technique in repairs done in patients even older than the age of 50.17 The 2 transosseous tunnel technique tied over a bony bridge with use of a button can similarly be used with repairs of anteromedial and anterolateral
D.J. Navasartian and T.M. DeBerardino meniscal roots.19 It has been noted that when 1 and 2 tunnel transosseous techniques using a surface tibial cortical button are compared, there is no significant difference in regard to displacement or load to failure when studied using human cadaveric specimens.23 There is evidence to show that the suture configuration at the point of suture-meniscus fixation could cause considerable variability in the biomechanical properties of the repair.24 In a study performed using porcine menisci, it was shown that a modified Masson-Allen stich had the highest load to failure, while the 2 stitch simple construct had the least displacement after cyclical loading (Fig. 4).24 These results however are reflective of a study performed only at time zero, and in a nonhuman model, which therefore should be considered when translating these conclusions to in vivo properties in human specimens overtime. A study performed in human cadaveric specimens also showed that of the stitch configurations included in the study, the 2 simple stitch configuration allowed for the least displacement after cyclical loading. When compared to the modified Masson-Allen stitch, which was included in the studied stitch configurations, the differences were not statistically significant.25 This study did however, as was the case in the porcine model study, demonstrate that Masson-Allen stitch had statistically significant greater load to failure.24,25 Further, it suggested its efficacy in meniscal root repairs given its relative ease of use and favorable biomechanical properties.25 The importance of the properties of the meniscal-suture point of fixation was highlighted in a study by Cerminara et al.26 This study demonstrated that the nature of the meniscussuture relationship was more critical than that of the button to bone relationship, or that of suture elongation, as a source of meniscal displacement after cyclical loading.26 Visualization and manipulation of structures in the posteromedial tibiofemoral joint space can sometimes be difficult.27 Given the relatively confined nature of this region of the knee, while performing repair or debridement of the posteromedial meniscus, iatrogenic cartilage injury can result.27To improve visualization and overall working space in the posteromedial tibiofemoral joint space, various techniques of MCL release have been performed.27-29 These techniques include “pie-crusting” of the MCL as well as subperiosteal release of the MCL.28,29 It has been demonstrated that pie-crusting of the MCL during partial mensicectomy does not result in long-term instability and results in less iatrogenic chondral damage.28 More specific to meniscal root repair, a study was performed that evaluated the results of release of the MCL while performing posterior root repair of the medial meniscus using a transtibial pullout technique.29 This study showed that the release of the superficial MCL (in this case using a subperiosteal release) resulted in a shorter operative time, and by 12 months, no patients had subjective increase in valgus laxity, and only 7% of patients had any valgus laxity appreciable on exam (grade I only).29
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Figure 4 Photograph of the various suture configurations tested by Feucht et al. (A) Two simple stitches, (B) horizontal mattress suture, (C) modified Mason-Allen suture, and (D) two modified loop stitches. The American Journal of Sports Medicine, Vol. 41, No. 12. DOI: 10.1177/0363546513502464. Copyright 2013 The Author(s). Reprinted under STM Guidelines.24
Suture Anchor Repair Repair of the meniscal root using suture anchors has shown promising results.30,31 In a study using porcine specimens, posterior meniscal root tears were repaired using either transosseous bone tunnels made in the tibia or with suture anchors purchasing directly into the root footprint.30 For both the suture anchor repairs and the transosseous repairs, the same suture material and suture configurations were used. The study found that the suture anchor repairs had less displacement after cyclical loading and also had greater stiffness, however, the differences in the load to failure between the 2 constructs were not found to be statistically significant.30 This study also showed that both of these constructs had strengths less than that of the native posteromedial meniscal root.30 In a prospective study using human specimens, the transosseous pullout technique was compared to that of the suture anchor technique.31 Both repair constructs resulted in functional improvements that were not statistically different between the 2 groups of patients.31 It should be noted however that the authors of this study indicated that they found it easier to obtain the appropriate tensioning with suture anchor construct, and suggested that this was due to the longer distance between the meniscus and definitive surface fixation in the transosseous construct.31 There has also been discussion in regard to the potential benefit of suture anchor fixation in situations where meniscal root repair is being carried out in the setting of bone tunnels that are being used for ligament reconstruction.14,31 Kim et al suggested that transosseous tunnel fixation of meniscal root tears cannot be performed in the setting of concomitant ACL repair.31 This could be particularly relevant given that there are data that show that in the ACL deficient knee a coexisting posterolateral meniscal root tear can increase knee instability.32 This was not found to be the case however in
the study performed by LaPrade et al, as a transosseous fixation technique was performed in the presence of concomitant cruciate ligament reconstruction.17 The specifics of the technique involved in suture anchor fixation of meniscal root tears have been described.33,34 A commonality in the techniques described by Choi et al and Kim et al is that in both cases, a high posteromedial portal was used as the working portal for anchor placement.33,34 A difference between the described techniques is found in the viewing portal used during anchor placement.33,34 The anterolateral portal was used as the viewing portal during anchor placement in the technique described by Choi et al, and in contrast, the technique described by Kim et al, a trans-septal viewing portal was used.33,34 Kim et al noted that this portal was preferentially used because it was thought to aid in
Figure 5 Arthroscopic image of FlipCutter in position of meniscal root footprint in position for retrograde reaming. Reprinted with permission.36
ARTICLE IN PRESS D.J. Navasartian and T.M. DeBerardino
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Figure 6 Arthroscopic image of left knee posterior medial meniscal root repair as sutures is being passed through the meniscal root using a self-retrieving suture passer. Image from Dr DeBerardino.
Figure 8 Arthroscopic image of left knee posterior medial meniscal root repair in the process of suture shuttling to outside of the knee through the tibial tunnel. Image from Dr DeBerardino.
reliable visualization of anchor placement.34 As previously mentioned when discussing transosseous repairs, the transseptal portal was also used by Ahn et al to aid in visualization when using the transtibial fixation technique.22 The transseptal portal was originally described by Ahn et al in the year 2000, and was noted to be a potentially valuable tool to be utilized in a number of various arthroscopic procedures.35 Furthermore, the use of the trans-septal portal for
visualization in techniques described for both the suture anchor and the transosseous constructs highlights the potential versatility of this portal, and demonstrates that this portal should be considered in meniscal root repair regardless of the technique employed.22,34,35 When creating this portal, Ahn et al note that care must be taken when using the shaver to create the channel in the septum in order to avoid injury to the PCL or the posterior capsule.35 Importantly, however,
Figure 7 Arthroscopic image of left knee posterior medial meniscal root repair after the first suture is passed through the meniscal root (A) and the subsequent view after the creation of 2 cinch loops (B). Image from Dr DeBerardino.
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Figure 9 Arthroscopic image of left knee posterior medial meniscal root repair after sutures has been shuttled through the tibial tunnel (A) and the final restoration of the meniscal root to its footprint on the tibia after suture tensioning and surface fixation have taken place (B). Image from Dr DeBerardino.
the authors note that in their experience there has not been any incidence of injury to the neurovascular bundle, which lies in close proximity to the posterior capsule.35
Author’s Preferred Technique The following is a discussion of the senior author's (DeBerardino) preferred technique in the operative treatment of posterior meniscal root tears. A standard diagnostic knee arthroscopy is performed and the menisci are examined and probed. In the case of a medial posterior meniscal root tear, the anteromedial portal is the working portal and the anterolateral portal is the viewing portal (this would be switched for a lateral tear). The separation of the meniscal root from its footprint is identified, and particular notation of the precise location of the anatomic footprint is made. A guide that is functionally similar to a tibial ACL guide (Meniscal Root Marking Hook, Arthrex Inc) is positioned such that the point of eventual drill exits into the joint is seated in the anatomic meniscal root footprint. The other point of contact for the guide is then positioned onto the metaphaseal region of the proximal anterior tibial cortex after a small skin incision is made that is large enough to accommodate guide docking, drilling, and suture passage. A retrograde reamer (FlipCutter, Arthrex Inc) is then used to create a tunnel from the meniscal root footprint to the proximal tibia anterior cortex (Fig. 5). The socket created in the footprint is only large enough to snuggly accommodate the meniscal root and the sutures that are to be placed. To accomplish this, a 6 mm FlipCutter (Arthrex Inc) is used, with attention to only denude the cartilage to a bleeding bone bed. Care must be taken to avoid the creation of an overly deep aperture, which could impede meniscus-bone apposition. Two sutures (0 FiberLink,
Arthrex Inc) are then passed into the meniscal root within the knee using a self-retrieving suture-passing device (Knee Scorpion, Arthrex Inc; Fig. 6). In performing this, 2 cinch stitches are created in the meniscal root (Fig. 7). These 2 sutures are then shuttled through the tibial tunnel to outside of the knee using a shuttling device (FiberStick, Arthrex Inc; Fig. 8). Following suture passage, an effort is made to ensure that creep is eliminated from the repair as best as possible. Once anatomic position of the meniscus is confirmed, the sutures are then fixated to the proximal tibial cortex using a knotless suture anchor (4.75 mm BioComposite SwiveLock, Arthrex Inc; Fig. 9). Finally, the integrity of the repair is inspected and probed to ensure anatomic position and firm fixation.
Acknowledgment Acknowledge of grant support when appropriate (“Supported in part by...”).
References 1. Fairbank T: Knee joint changes after meniscectomy. J Bone Joint Surg Br 30:664-670, 1948 2. Radin EL, de Lamotte F, Maquet P: Role of the menisci in the distribution of stress in the knee. Clin Orthop Relat Res 185:290-294, 1984 3. Allaire R, Muriuki M, Gilbertson L, et al: Biomechanical consequences of a tear of the posterior root of the medial meniscus similar to total meniscectomy. J Bone Joint Surg Am 90:1922-1931, 2008 4. LaPrade CM, James EW, Cram TR, et al: Meniscal root tears: A classification system based on tear morphology. Am J Sports Med 43:363-369, 2015 5. Bhatia S, LaPrade CM, Ellman MB, et al: Meniscal root tears: Significance, diagnosis, and treatment. Am J Sports Med 42:3016-3030, 2014
ARTICLE IN PRESS 8 6. Petersen W, Forkel P, Feucht MJ, et al: Posterior root tear of the medial and lateral meniscus. Arch Orthop Trauma Surg 134:237-255, 2014 7. Lee JH, Lim YJ, Kim KB, et al: Arthroscopic pullout suture repair of posterior root tear of the medial meniscus: Radiographic and clinical results with a 2-year follow-up. Arthroscopy 25:951-958, 2009 8. Seil R, D€ uck K, Pape D: A clinical sign to detect root avulsions of the posterior horn of the medial meniscus. Knee Surg Sports Traumatol Arthrosc 19:2072-2075, 2011 9. Bin S, Kim J, Shin S: Radial tears of the posterior horn of the medial meniscus. Arthroscopy 20:373-378, 2004 10. Brody JM, Hulstyn MJ, Fleming BC, et al: The meniscal roots: Gross anatomic correlation with 3-T MRI findings. AJR 188:W446, 2007 11. Casagranda B.U., Leeman J., Costello J.M., et al: Coronal oblique imaging of the knee: can Can it increase radiologists' confidence in diagnosing posterior root meniscal tears? Clinical radiology. 2013;68:e316e322. 12. Lee YG, Shim J, Choi YS, et al: Magnetic resonance imaging findings of surgically proven medial meniscus root tear: Tear configuration and associated knee abnormalities. J Comput Assist Tomogr 32:452-457, 2008 13. Krych AJ, Reardon PJ, Johnson NR, et al: Non-operative management of medial meniscus posterior horn root tears is associated with worsening arthritis and poor clinical outcome at 5-year follow-up. Knee Surg Sports Traumatol Arthrosc 25:383-389, 2017 14. Koenig JH, Ranawat AS, Umans HR, et al: Meniscal root tears: Diagnosis and treatment. Arthroscopy 25:1025-1032, 2009 15. Ozkoc G, Circi E, Gonc U, et al: Radial tears in the root of the posterior horn of the medial meniscus. Knee Surg Sports Traumatol Arthrosc 16:849-854, 2008 16. Kim JG, Kim DW, Kim SB, et al: Medial meniscus root tear refixation: Comparison of clinical, radiologic, and arthroscopic findings with medial meniscectomy. Arthroscopy 27:346-354, 2011 17. LaPrade RF, Matheny LM, Moulton SG, et al: Posterior meniscal root repairs: Outcomes of an Anatomic transtibial pull-out technique. Am J Sports Med 45:884-891, 2017 18. Osti L, Del Buono A, Maffulli N: Anterior medial meniscal root tears: A novel arthroscopic all inside repair. Transl Med UniSa 12:41, 2015 19. Menge TJ, Chahla J, Dean CS, et al: Anterior meniscal root repair using a transtibial double-tunnel pullout technique. Arthrosc Tech 5:e679e684, 2016 20. Raustol OA, Poelstra KA, Chhabra A, et al: The Meniscal ossicle revisited: Etiology and an arthroscopic technique for treatment. Arthroscopy 22, 2006. e1-687.e3 21. Frank JM, Liechti DJ, Anavian J, et al: A transosseous bone bridge repair for posterior horn meniscal root tears during anterior cruciate ligament reconstruction. Arthrosc Tech 6(1):e239-e243, 2017
D.J. Navasartian and T.M. DeBerardino 22. Ahn JH, Wang JH, Lim HC, et al: Double transosseous pull out suture technique for transection of posterior horn of medial meniscus. Arch Orthop Trauma Surg 129:387-392, 2009 23. LaPrade CM, LaPrade MD, Turnbull TL, et al: Biomechanical evaluation of the transtibial pull-out technique for posterior medial meniscal root repairs using 1 and 2 transtibial bone tunnels. Am J Sports Med 43:899904, 2015 24. Feucht MJ, Grande E, Brunhuber J, et al: Biomechanical evaluation of different suture materials for arthroscopic transtibial pull-out repair of posterior meniscus root tears. Knee Surg Sports Traumatol Arthrosc 23:132-139, 2015 25. LaPrade RF, LaPrade CM, Ellman MB, et al: Cyclic displacement after meniscal root repair fixation: A human biomechanical evaluation. Am J Sports Med 43:892-898, 2015 26. Cerminara AJ, LaPrade CM, Smith SD, et al: Biomechanical evaluation of a transtibial pull-out meniscal root repair: Challenging the bungee effect. Am J Sports Med 42:2988-2995, 2014 27. Fakioglu O, Ozsoy MH, Ozdemir HM, et al: Percutaneous medial collateral ligament release in arthroscopic medial meniscectomy in tight knees. Knee Surg Sports Traumatol Arthrosc 21:1540-1545, 2013 28. Claret G, Monta~ nana J, Rios J, et al: The effect of percutaneous release of the medial collateral ligament in arthroscopic medial meniscectomy on functional outcome. Knee 23:251-255, 2016 29. Chung K.S., Kim J.G., Ha J.K., et al: Does release of superficial medial collateral ligament result in clinically harmful effects after fixation of medial meniscus posterior root tears? Asia -Pacific Journal of Sports Medicine. 9:97-98, 2017 30. Feucht MJ, Grande E, Brunhuber J, et al: Biomechanical comparison between suture anchor and transtibial pull-out repair for posterior medial meniscus root tears. Am J Sports Med 42:187-193, 2014 31. Kim J, Chung J, Lee D, et al: Arthroscopic suture anchor repair versus pullout suture repair in posterior root tear of the medial meniscus: A prospective comparison study. Arthroscopy 27:1644-1653, 2011 32. Shybut TB, Vega CE, Haddad J, et al: Effect of lateral meniscal root tear on the stability of the anterior cruciate LigamentDeficient knee. Am J Sports Med 43:905-911, 2015 33. Choi N, Son K, Victoroff BN: Arthroscopic all-inside repair for a tear of posterior root of the medial meniscus: A technical note. Knee Surg Sports Traumatol Arthrosc 16:891-893, 2008 34. Kim J, Shin D, Dan J, et al: Arthroscopic suture anchor repair of posterior root attachment injury in medial meniscus: Technical note. Arch Orthop Trauma Surg 129:1085-1088, 2009 35. Ahn J, Ha CW: Posterior trans-septal portal for arthroscopic surgery of the knee joint. Arthroscopy 16:774-779, 2000 36. Nicholas SJ, Golant A, Schachter AK, et al: A new surgical technique for arthroscopic repair of the meniscus root tear. Knee Surg Sports Traumatol Arthrosc Offi J ESSKA 17:1433-1436, 2009
Meniscus Root Repair Douglas J. Navasartian, MD, MS,* and Thomas M. DeBerardino, MDz,1 It has long been recognized that injuries to the menisci have a significantly detrimental effect on knee kinematics and can cause pathology within the knee joint. The consequences of these tears can lead to progressive degenerative changes of the chondral surfaces in the knee. Because of the deleterious sequelae of meniscal root tears, identification of these tears and a means of potential surgical treatment are paramount. The following is a discussion of meniscal root tears and the surgical techniques that can be utilized in operative treatment. Oper Tech Sports Med 00:1-8 © 2018 Elsevier Inc. All rights reserved.
KEYWORDS Meniscal root tear, meniscal root tear repair
Introduction
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t has been demonstrated as early as 1948 that mensicectomy leads to damage of the knee articular cartilage.1 A key function of the meniscus is to dissipate hoop stress.2 Allaire et al showed that disruption of the posterior root of the medial meniscus significantly decreases the ability of the meniscus to dissipate this stress.3 The effect of such a tear was shown to result in contact pressures that approximated that of total medial mensicectomy.3 Interestingly, the study by Allaire et al also revealed that repair of the posterior root of the medial meniscus resulted in restoration of the ability of the meniscus to dissipate contact pressures.3 Given that tear patterns of the meniscal root vary, a means of classification can assist in uniformity in the description of tears across various providers and potentially aid in the specificity of communication regarding these injuries. A classification system of meniscal root tears was developed by LaPrade et al (Fig. 1).4 This classification system uses meniscal root tear morphology as a means of separating out 5 different patterns of tears. The first type is a partial tear and is considered stable. The second is a tear within 9 mm of the root attachment to the tibia and is complete. The third type *Orthopaedic Sports Medicine, The Combined Baylor College of Medicine and San Antonio Orthopaedic Group, Texas Sports Medicine Fellowship, San Antonio and Houston, TX. z Burkhart Research Institute for Orthopaedics (BRIO) and the Sports Institute at TSAOG Orthopaedics, San Antonio, TX. Address reprint requests to Thomas M. DeBerardino, MD, 635 Elizabeth Rd, San Antonio, TX 78209-6134. E-mail: [email protected] 1 The name of the institution where the work reported was done (“From...”) From The Sports Institute at the San Antonio Orthopaedic Group.
https://doi.org/10.1053/j.otsm.2018.10.004 1060-1872/© 2018 Elsevier Inc. All rights reserved.
is a complete detachment of a bucket handle tear extending through, and including, the meniscal root. The fourth type is a complex oblique tear that extends into the meniscal root. The fifth type is an avulsion fracture of the root attachment. The most common of these types in the population investigated in their study was the type 2 morphologic pattern, which was seen in 67.6% of the subjects.4 Because of the morbidity that can be caused by meniscal root tears, accurate diagnosis is imperative. The diagnosis of meniscal root tears however can be difficult. As reviewed by Bhatia et al and Petersen et al, there can be considerable variability in regard to how meniscal tears present clinically.5,6 These discussions note the original research of Lee et al and Seil et al.5-8 In a study performed by Lee et al, the clinical manifestations of 21 posterior root tears of the medial meniscus were described.7 Only 9.5% reported a “giving way” event, and only 14.3 % described locking of the knee. Potential findings noted on physical examination were pain on full flexion, joint line tenderness, positive McMurray's, and knee effusion. Of these findings, pain on full flexion was the most commonly observed; however, even this was only demonstrated in approximately two-thirds of patients.7 Seil et al noted that the application of a varus stress while simultaneously palpating the anteromedial meniscus could elicit meniscus extrusion, and in this manner could aid in the diagnosis of root avulsions of the posterior horn of the medial meniscus.8 Multiple articles have also discussed the clinical manifestations of meniscal root tears as delineated by the 2004 research by Bin et al.6-9 In this study, 100% of the knees with posteromedial meniscal root tears
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Figure 1 Illustration of the classification system of meniscal root tears based on tear morphology developed by LaPrade et al. Type I: partial tear, considered stable. Type 2: tear within 9 mm of the root attachment to the tibia, complete. Type 3: complete detachment of a bucket handle tear extending through, and including, the meniscal root. Type 4: complex oblique tear that extends into the meniscal root. Type 5: an avulsion fracture of the root attachment. The American Journal of Sports Medicine, Vol. 43, No. 2. DOI: 10.1177/0363546514559684. Copyright 2014 The Author (s). Reprinted under STM Guidelines.4
had a knee effusion.9 Although this finding is nonspecific, it was the most common clinical indicator of a meniscal root tear that was identified in the study.9 This is vastly different than the findings by Lee et al, which found that 14.3% of the patients had a knee effusion.7 Such variability in patient presentation underlines the challenges that can be encountered when diagnosing meniscal root tears clinically. Magnetic resonance imaging (MRI) has the ability to delineate the anatomy of the meniscal roots in detail.10 Furthermore, MRI has been shown to be helpful in the diagnosis of the presence of meniscal root tears.11 In a study by Lee et al, MRI findings of medial meniscal root tears were evaluated.12 In this study, although the overall diagnostic capabilities of the MRI to determine the presence of a tear posterior horn medial meniscus root were high, all complex tears of the posterior horn medial meniscus root were misdiagnosed as radial tears. The authors note however that this inability to differentiate the 2 would not affect the ultimate surgical plan of care.12
Treatment The treatments for meniscal root tears can be either operative or nonoperative. The decision as to proceed with nonoperative treatment depends on specific patient characteristics. It has been suggested that patients who are poor surgical candidates or patients with significant degenerative changes should undergo a trial of nonoperative management, and that these treatment measures can extend from bracing, to activity modification, to medications.5 In a study by Krych et al, a retrospective review of 52 patients who were treated nonoperatively for root tears of the posterior horn of the medial meniscus.13 The response of this population to nonoperative treatment was studied, as was their rate of conversion to total knee arthroplasty.13 It was found that 87% of patients failed nonoperative treatment, and that by conclusion of the study period, a total of 31% of patients underwent total knee arthroplasty.13 Given that meniscal root tears can lead to a significant increase in the stress experienced by the tibiofemoral joint (and therefore degenerative changes),
ARTICLE IN PRESS Meniscus Root Repair patients with already advanced degenerative changes should attempt conservative measures with symptomatic treatment before being considered for a total knee arthroplasty.3,5 When a patient is indicated for operative treatment, surgical options include partial meniscectomy or repair.5,14,15 It has been shown however that in the case of radial root tears in the posterior horn of the medial meniscus, although partial mensicectomy can be effective in relieving pain initially, it does not prevent degenerative changes in the knee.15 This is in contrast to the meniscal root repair, which has been noted to restore the hoop stress dissipation provided by the meniscus.3 Such restoration of hoop stress allowed by repair could help prevent the advancement of degenerative changes that would have been caused by either leaving the tear or by meniscectomy. A study done by Kim et al showed that arthroscopic repair of medial meniscal root tears resulted in less progression toward arthritic degeneration as well as better clinical outcomes when compared to partial meniscectomy.16 Determination of which patients should be considered for meniscal root repair is dependent on a number of factors. As discussed by Bhatia et al, younger patients without significant chondral damage who sustained a traumatic tear are ideal candidates for repair.5 In their review, an algorithm was suggested which favored acute tears being repaired, and chronic tears being repaired if there were not grade III or IV arthritis. If these patients did have these stages of degenerative changes, then symptomatic tears were treated with partial mensicectomy.5 A study done by LaPrade et al showed that patients similarly benefited from repair of posterior meniscal root tears regardless of the patients being younger or older than 50 years of age.17 This study also demonstrated similarly high patient satisfaction scores regardless of whether the repair was performed on the medial or lateral meniscus.17
Repair Repair of the meniscal root, whether medial or lateral, can be performed in a number of ways. These methods included transosseous repairs and repairs that use anchors.5,14 The literature regarding the surgical techniques of meniscal root repair is more readily found in regard to posterior meniscal root tears as opposed to anterior meniscal root tears, for which there is a relative scarcity of information.5 More recently, however, there been descriptions of similar techniques that can also be utilized for anterior meniscus root repair.18,19
Transosseous Repairs Transosseous repairs can be carried out using a bone bridge for suture fixation or through the use of bone tunnels that are used to shuttle sutures for eventual fixation of the sutures to the bone using a button or anchor.5,14 The use of a bony bridge for fixation after passage through transtibial tunnels has been described by a number of authors.20-22 An example
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Figure 2 Illustration of the fixation of the posteromedial meniscal root ossicle through the a posteromedial working portal using a Beath pin in what Raustol et al describe as being the appropriate trajectory. Note the suture preloaded through its eyelet. Reprinted with permission.20
of this is in the technique described by Raustol et al, fixation of a meniscal ossicle of the posteromedial meniscal root was performed through the use of a posteromedial working portal and a Beath pin (Fig. 2).20 The posteromedial portal was established, the meniscal ossicle reduced, the Beath pin (preloaded with suture through its eyelet) was passed from the posteromedial portal, through the fragment, and finally the pin advanced through the tibia until the came out the anteromedial aspect of the tibial cortex with the suture through its end.20 This was performed twice, making a mattress stitch through the fragment, and the suture ends were tied over a 10 mm bone bridge over the anteromedial tibia.20 Given that visualization of the meniscal root footprint can be challenging when multiple instruments are being used, Ahn et al made the use of a posterior trans-septal viewing portal and a posteromedial working portal to perform transosseous repair of the posterior horn of the medial meniscus with bone bridge fixation.22 In this technique, a posterolateral portal is a conduit for arthroscope entry into the posteromedial compartment through a trans-septal portal, which is used for viewing.22 A high posteromedial working portal is used to allow for passage of 3 mattress stitches, with a limb from each end of the stitch penetrating the meniscus in the anterior to posterior direction along the meniscal root. An anterior cruciate ligament guide was then used to introduce 2 pins from the anteromedial tibia to the position of the decorticated meniscal root footprint.22 These channels would then serve as retrieval tunnels for a wire suture passer to retrieve the sutures that were passed through the meniscus. The sutures are then retrieved and tied anteromedial tibial bone bridge.22 In the article, Ahn et al make analogy of the described technique being comparable to that of double row
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Figure 3 Arthroscopic view from the posterolateral portal looking through to the posteromedial compartment via the posterior transseptal portal. (A) The suture limbs being pulled through their respective bone tunnels. (B) The meniscal root after reduction, tensioning, and suture fixation over cortical bone bridge. Reprinted with permission.22
rotator cuff repair, in that through the use of the mattress sutures and 2 spaced transosseous tunnels, a larger surface area of meniscus to decorticated bone contact is created, and therefore a larger footprint for healing is made (Fig. 3).22 The technique described by LaPrade et al also uses 2 bone tunnels with the surface of the anteromedial tibia cortex serving as a point of fixation through use of a boney bridge; however, in this case, there is a different suture configuration and the sutures are first passed through a device (eg, button) before being fixated by means of a bony bridge to the cortex of the tibia.17 This study, as previously alluded to, also highlighted the efficacy of this technique in repairs done in patients even older than the age of 50.17 The 2 transosseous tunnel technique tied over a bony bridge with use of a button can similarly be used with repairs of anteromedial and anterolateral
D.J. Navasartian and T.M. DeBerardino meniscal roots.19 It has been noted that when 1 and 2 tunnel transosseous techniques using a surface tibial cortical button are compared, there is no significant difference in regard to displacement or load to failure when studied using human cadaveric specimens.23 There is evidence to show that the suture configuration at the point of suture-meniscus fixation could cause considerable variability in the biomechanical properties of the repair.24 In a study performed using porcine menisci, it was shown that a modified Masson-Allen stich had the highest load to failure, while the 2 stitch simple construct had the least displacement after cyclical loading (Fig. 4).24 These results however are reflective of a study performed only at time zero, and in a nonhuman model, which therefore should be considered when translating these conclusions to in vivo properties in human specimens overtime. A study performed in human cadaveric specimens also showed that of the stitch configurations included in the study, the 2 simple stitch configuration allowed for the least displacement after cyclical loading. When compared to the modified Masson-Allen stitch, which was included in the studied stitch configurations, the differences were not statistically significant.25 This study did however, as was the case in the porcine model study, demonstrate that Masson-Allen stitch had statistically significant greater load to failure.24,25 Further, it suggested its efficacy in meniscal root repairs given its relative ease of use and favorable biomechanical properties.25 The importance of the properties of the meniscal-suture point of fixation was highlighted in a study by Cerminara et al.26 This study demonstrated that the nature of the meniscussuture relationship was more critical than that of the button to bone relationship, or that of suture elongation, as a source of meniscal displacement after cyclical loading.26 Visualization and manipulation of structures in the posteromedial tibiofemoral joint space can sometimes be difficult.27 Given the relatively confined nature of this region of the knee, while performing repair or debridement of the posteromedial meniscus, iatrogenic cartilage injury can result.27To improve visualization and overall working space in the posteromedial tibiofemoral joint space, various techniques of MCL release have been performed.27-29 These techniques include “pie-crusting” of the MCL as well as subperiosteal release of the MCL.28,29 It has been demonstrated that pie-crusting of the MCL during partial mensicectomy does not result in long-term instability and results in less iatrogenic chondral damage.28 More specific to meniscal root repair, a study was performed that evaluated the results of release of the MCL while performing posterior root repair of the medial meniscus using a transtibial pullout technique.29 This study showed that the release of the superficial MCL (in this case using a subperiosteal release) resulted in a shorter operative time, and by 12 months, no patients had subjective increase in valgus laxity, and only 7% of patients had any valgus laxity appreciable on exam (grade I only).29
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Figure 4 Photograph of the various suture configurations tested by Feucht et al. (A) Two simple stitches, (B) horizontal mattress suture, (C) modified Mason-Allen suture, and (D) two modified loop stitches. The American Journal of Sports Medicine, Vol. 41, No. 12. DOI: 10.1177/0363546513502464. Copyright 2013 The Author(s). Reprinted under STM Guidelines.24
Suture Anchor Repair Repair of the meniscal root using suture anchors has shown promising results.30,31 In a study using porcine specimens, posterior meniscal root tears were repaired using either transosseous bone tunnels made in the tibia or with suture anchors purchasing directly into the root footprint.30 For both the suture anchor repairs and the transosseous repairs, the same suture material and suture configurations were used. The study found that the suture anchor repairs had less displacement after cyclical loading and also had greater stiffness, however, the differences in the load to failure between the 2 constructs were not found to be statistically significant.30 This study also showed that both of these constructs had strengths less than that of the native posteromedial meniscal root.30 In a prospective study using human specimens, the transosseous pullout technique was compared to that of the suture anchor technique.31 Both repair constructs resulted in functional improvements that were not statistically different between the 2 groups of patients.31 It should be noted however that the authors of this study indicated that they found it easier to obtain the appropriate tensioning with suture anchor construct, and suggested that this was due to the longer distance between the meniscus and definitive surface fixation in the transosseous construct.31 There has also been discussion in regard to the potential benefit of suture anchor fixation in situations where meniscal root repair is being carried out in the setting of bone tunnels that are being used for ligament reconstruction.14,31 Kim et al suggested that transosseous tunnel fixation of meniscal root tears cannot be performed in the setting of concomitant ACL repair.31 This could be particularly relevant given that there are data that show that in the ACL deficient knee a coexisting posterolateral meniscal root tear can increase knee instability.32 This was not found to be the case however in
the study performed by LaPrade et al, as a transosseous fixation technique was performed in the presence of concomitant cruciate ligament reconstruction.17 The specifics of the technique involved in suture anchor fixation of meniscal root tears have been described.33,34 A commonality in the techniques described by Choi et al and Kim et al is that in both cases, a high posteromedial portal was used as the working portal for anchor placement.33,34 A difference between the described techniques is found in the viewing portal used during anchor placement.33,34 The anterolateral portal was used as the viewing portal during anchor placement in the technique described by Choi et al, and in contrast, the technique described by Kim et al, a trans-septal viewing portal was used.33,34 Kim et al noted that this portal was preferentially used because it was thought to aid in
Figure 5 Arthroscopic image of FlipCutter in position of meniscal root footprint in position for retrograde reaming. Reprinted with permission.36
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Figure 6 Arthroscopic image of left knee posterior medial meniscal root repair as sutures is being passed through the meniscal root using a self-retrieving suture passer. Image from Dr DeBerardino.
Figure 8 Arthroscopic image of left knee posterior medial meniscal root repair in the process of suture shuttling to outside of the knee through the tibial tunnel. Image from Dr DeBerardino.
reliable visualization of anchor placement.34 As previously mentioned when discussing transosseous repairs, the transseptal portal was also used by Ahn et al to aid in visualization when using the transtibial fixation technique.22 The transseptal portal was originally described by Ahn et al in the year 2000, and was noted to be a potentially valuable tool to be utilized in a number of various arthroscopic procedures.35 Furthermore, the use of the trans-septal portal for
visualization in techniques described for both the suture anchor and the transosseous constructs highlights the potential versatility of this portal, and demonstrates that this portal should be considered in meniscal root repair regardless of the technique employed.22,34,35 When creating this portal, Ahn et al note that care must be taken when using the shaver to create the channel in the septum in order to avoid injury to the PCL or the posterior capsule.35 Importantly, however,
Figure 7 Arthroscopic image of left knee posterior medial meniscal root repair after the first suture is passed through the meniscal root (A) and the subsequent view after the creation of 2 cinch loops (B). Image from Dr DeBerardino.
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Figure 9 Arthroscopic image of left knee posterior medial meniscal root repair after sutures has been shuttled through the tibial tunnel (A) and the final restoration of the meniscal root to its footprint on the tibia after suture tensioning and surface fixation have taken place (B). Image from Dr DeBerardino.
the authors note that in their experience there has not been any incidence of injury to the neurovascular bundle, which lies in close proximity to the posterior capsule.35
Author’s Preferred Technique The following is a discussion of the senior author's (DeBerardino) preferred technique in the operative treatment of posterior meniscal root tears. A standard diagnostic knee arthroscopy is performed and the menisci are examined and probed. In the case of a medial posterior meniscal root tear, the anteromedial portal is the working portal and the anterolateral portal is the viewing portal (this would be switched for a lateral tear). The separation of the meniscal root from its footprint is identified, and particular notation of the precise location of the anatomic footprint is made. A guide that is functionally similar to a tibial ACL guide (Meniscal Root Marking Hook, Arthrex Inc) is positioned such that the point of eventual drill exits into the joint is seated in the anatomic meniscal root footprint. The other point of contact for the guide is then positioned onto the metaphaseal region of the proximal anterior tibial cortex after a small skin incision is made that is large enough to accommodate guide docking, drilling, and suture passage. A retrograde reamer (FlipCutter, Arthrex Inc) is then used to create a tunnel from the meniscal root footprint to the proximal tibia anterior cortex (Fig. 5). The socket created in the footprint is only large enough to snuggly accommodate the meniscal root and the sutures that are to be placed. To accomplish this, a 6 mm FlipCutter (Arthrex Inc) is used, with attention to only denude the cartilage to a bleeding bone bed. Care must be taken to avoid the creation of an overly deep aperture, which could impede meniscus-bone apposition. Two sutures (0 FiberLink,
Arthrex Inc) are then passed into the meniscal root within the knee using a self-retrieving suture-passing device (Knee Scorpion, Arthrex Inc; Fig. 6). In performing this, 2 cinch stitches are created in the meniscal root (Fig. 7). These 2 sutures are then shuttled through the tibial tunnel to outside of the knee using a shuttling device (FiberStick, Arthrex Inc; Fig. 8). Following suture passage, an effort is made to ensure that creep is eliminated from the repair as best as possible. Once anatomic position of the meniscus is confirmed, the sutures are then fixated to the proximal tibial cortex using a knotless suture anchor (4.75 mm BioComposite SwiveLock, Arthrex Inc; Fig. 9). Finally, the integrity of the repair is inspected and probed to ensure anatomic position and firm fixation.
Acknowledgment Acknowledge of grant support when appropriate (“Supported in part by...”).
References 1. Fairbank T: Knee joint changes after meniscectomy. J Bone Joint Surg Br 30:664-670, 1948 2. Radin EL, de Lamotte F, Maquet P: Role of the menisci in the distribution of stress in the knee. Clin Orthop Relat Res 185:290-294, 1984 3. Allaire R, Muriuki M, Gilbertson L, et al: Biomechanical consequences of a tear of the posterior root of the medial meniscus similar to total meniscectomy. J Bone Joint Surg Am 90:1922-1931, 2008 4. LaPrade CM, James EW, Cram TR, et al: Meniscal root tears: A classification system based on tear morphology. Am J Sports Med 43:363-369, 2015 5. Bhatia S, LaPrade CM, Ellman MB, et al: Meniscal root tears: Significance, diagnosis, and treatment. Am J Sports Med 42:3016-3030, 2014
ARTICLE IN PRESS 8 6. Petersen W, Forkel P, Feucht MJ, et al: Posterior root tear of the medial and lateral meniscus. Arch Orthop Trauma Surg 134:237-255, 2014 7. Lee JH, Lim YJ, Kim KB, et al: Arthroscopic pullout suture repair of posterior root tear of the medial meniscus: Radiographic and clinical results with a 2-year follow-up. Arthroscopy 25:951-958, 2009 8. Seil R, D€ uck K, Pape D: A clinical sign to detect root avulsions of the posterior horn of the medial meniscus. Knee Surg Sports Traumatol Arthrosc 19:2072-2075, 2011 9. Bin S, Kim J, Shin S: Radial tears of the posterior horn of the medial meniscus. Arthroscopy 20:373-378, 2004 10. Brody JM, Hulstyn MJ, Fleming BC, et al: The meniscal roots: Gross anatomic correlation with 3-T MRI findings. AJR 188:W446, 2007 11. Casagranda B.U., Leeman J., Costello J.M., et al: Coronal oblique imaging of the knee: can Can it increase radiologists' confidence in diagnosing posterior root meniscal tears? Clinical radiology. 2013;68:e316e322. 12. Lee YG, Shim J, Choi YS, et al: Magnetic resonance imaging findings of surgically proven medial meniscus root tear: Tear configuration and associated knee abnormalities. J Comput Assist Tomogr 32:452-457, 2008 13. Krych AJ, Reardon PJ, Johnson NR, et al: Non-operative management of medial meniscus posterior horn root tears is associated with worsening arthritis and poor clinical outcome at 5-year follow-up. Knee Surg Sports Traumatol Arthrosc 25:383-389, 2017 14. Koenig JH, Ranawat AS, Umans HR, et al: Meniscal root tears: Diagnosis and treatment. Arthroscopy 25:1025-1032, 2009 15. Ozkoc G, Circi E, Gonc U, et al: Radial tears in the root of the posterior horn of the medial meniscus. Knee Surg Sports Traumatol Arthrosc 16:849-854, 2008 16. Kim JG, Kim DW, Kim SB, et al: Medial meniscus root tear refixation: Comparison of clinical, radiologic, and arthroscopic findings with medial meniscectomy. Arthroscopy 27:346-354, 2011 17. LaPrade RF, Matheny LM, Moulton SG, et al: Posterior meniscal root repairs: Outcomes of an Anatomic transtibial pull-out technique. Am J Sports Med 45:884-891, 2017 18. Osti L, Del Buono A, Maffulli N: Anterior medial meniscal root tears: A novel arthroscopic all inside repair. Transl Med UniSa 12:41, 2015 19. Menge TJ, Chahla J, Dean CS, et al: Anterior meniscal root repair using a transtibial double-tunnel pullout technique. Arthrosc Tech 5:e679e684, 2016 20. Raustol OA, Poelstra KA, Chhabra A, et al: The Meniscal ossicle revisited: Etiology and an arthroscopic technique for treatment. Arthroscopy 22, 2006. e1-687.e3 21. Frank JM, Liechti DJ, Anavian J, et al: A transosseous bone bridge repair for posterior horn meniscal root tears during anterior cruciate ligament reconstruction. Arthrosc Tech 6(1):e239-e243, 2017
D.J. Navasartian and T.M. DeBerardino 22. Ahn JH, Wang JH, Lim HC, et al: Double transosseous pull out suture technique for transection of posterior horn of medial meniscus. Arch Orthop Trauma Surg 129:387-392, 2009 23. LaPrade CM, LaPrade MD, Turnbull TL, et al: Biomechanical evaluation of the transtibial pull-out technique for posterior medial meniscal root repairs using 1 and 2 transtibial bone tunnels. Am J Sports Med 43:899904, 2015 24. Feucht MJ, Grande E, Brunhuber J, et al: Biomechanical evaluation of different suture materials for arthroscopic transtibial pull-out repair of posterior meniscus root tears. Knee Surg Sports Traumatol Arthrosc 23:132-139, 2015 25. LaPrade RF, LaPrade CM, Ellman MB, et al: Cyclic displacement after meniscal root repair fixation: A human biomechanical evaluation. Am J Sports Med 43:892-898, 2015 26. Cerminara AJ, LaPrade CM, Smith SD, et al: Biomechanical evaluation of a transtibial pull-out meniscal root repair: Challenging the bungee effect. Am J Sports Med 42:2988-2995, 2014 27. Fakioglu O, Ozsoy MH, Ozdemir HM, et al: Percutaneous medial collateral ligament release in arthroscopic medial meniscectomy in tight knees. Knee Surg Sports Traumatol Arthrosc 21:1540-1545, 2013 28. Claret G, Monta~ nana J, Rios J, et al: The effect of percutaneous release of the medial collateral ligament in arthroscopic medial meniscectomy on functional outcome. Knee 23:251-255, 2016 29. Chung K.S., Kim J.G., Ha J.K., et al: Does release of superficial medial collateral ligament result in clinically harmful effects after fixation of medial meniscus posterior root tears? Asia -Pacific Journal of Sports Medicine. 9:97-98, 2017 30. Feucht MJ, Grande E, Brunhuber J, et al: Biomechanical comparison between suture anchor and transtibial pull-out repair for posterior medial meniscus root tears. Am J Sports Med 42:187-193, 2014 31. Kim J, Chung J, Lee D, et al: Arthroscopic suture anchor repair versus pullout suture repair in posterior root tear of the medial meniscus: A prospective comparison study. Arthroscopy 27:1644-1653, 2011 32. Shybut TB, Vega CE, Haddad J, et al: Effect of lateral meniscal root tear on the stability of the anterior cruciate LigamentDeficient knee. Am J Sports Med 43:905-911, 2015 33. Choi N, Son K, Victoroff BN: Arthroscopic all-inside repair for a tear of posterior root of the medial meniscus: A technical note. Knee Surg Sports Traumatol Arthrosc 16:891-893, 2008 34. Kim J, Shin D, Dan J, et al: Arthroscopic suture anchor repair of posterior root attachment injury in medial meniscus: Technical note. Arch Orthop Trauma Surg 129:1085-1088, 2009 35. Ahn J, Ha CW: Posterior trans-septal portal for arthroscopic surgery of the knee joint. Arthroscopy 16:774-779, 2000 36. Nicholas SJ, Golant A, Schachter AK, et al: A new surgical technique for arthroscopic repair of the meniscus root tear. Knee Surg Sports Traumatol Arthrosc Offi J ESSKA 17:1433-1436, 2009