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Arthrosc Tech
Arthrosc Tech
Arthroscopy Techniques
2212-6287
Elsevier

S2212-6287(24)00136-1
10.1016/j.eats.2024.103027
103027
Technical Note
Knee
Medial Meniscus Posterior Root Transtibial Pullout Repair With Progressively Tensioning Subcortical Fixation Button
Perelli Simone Ph.D. a
Pizza Nicola M.D. nicola.pizza@icatme.com
a∗
Gulmini Marco M.D. a
Ibañez Maximiliano M.D. a
Morales Avalos Rodolfo M.D. b
Torres-Claramunt Raul Ph.D. a
Monllau Juan Carlos Ph.D. a
a Knee and Arthroscopy Unit, ICATME, Hospital Universitari Dexeus, Universitat Autònoma de Barcelona, Barcelona, Spain
b Knee Unit, Department of Orthopedic Surgery and Traumatology, University Hospital “Dr. José Eleuterio González,” Universidad Autonoma de Nuevo León, Monterrey, Mexico
∗ Address correspondence to Nicola Pizza, M.D., Knee and Arthroscopy Unit, ICATME, Hospital Universitari Dexeus, Universitat Autònoma de Barcelona, Carrer Sabino de Arana 5-19, 08028, Barcelona, Spain. nicola.pizza@icatme.com
18 5 2024
8 2024
18 5 2024
13 8 10302727 11 2023
28 3 2024
© 2024 The Authors
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
We describe a surgical technique to repair medial meniscus posterior root tears through a transtibial pullout repair with a subcortical button for tibial fixation. This technique allows progressive tensioning of the repaired root without losing tension both during suturing of the knots above the button and after the procedure, owing to the specific button configuration.

Technique Video

Video 1

Medial meniscus posterior root (MMPR) transtibial pullout repair with progressively tensioning subcortical fixation button. A standard anterolateral arthroscopic portal is placed to explore the entire joint and decide the best position for the anteromedial (AM) portal, which is placed under direct visualization. The medial compartment is explored while valgus stress is applied. The medial meniscus is palpated with a probe, and the integrity of the whole meniscal body is checked. If an MMPR tear is present, pie crusting of the superficial medial collateral ligament is performed to open the compartment. The detached root is grasped and pulled in the direction of its anatomic insertion to check its reducibility. The remnant of the root attached to the bone and surrounding cartilage is debrided to expose the subchondral bleeding bone. A suture-passing device previously loaded with a No. 2 Ultrabraid suture is used to pass the first suture in the posterior root’s most medial aspect from the tibial to femoral side in a loop configuration. The loop is retrieved outside the AM portal with a rotator cuff grasper. A second Ultrabraid suture of a different color is passed through the meniscus in the same manner. A 2- to 3-cm incision is performed at the anterolateral aspect of the tibia. The tibialis anterior fibers are smoothly dissected to reach the tibial periosteum, which is gently elevated. A low-profile tibial guide is positioned over the debrided root to reproduce its anatomic position, and a transtibial meniscal root repair device, composed of a 4.5-mm cannula over a guidewire, is drilled into the joint. The tibial guide is removed, and the cannula is gently hammered into the joint. It is important to check if arthroscopic solution is now coming out of the cannula; this will mean that no drilled bone is present and the further steps can be performed. A suture retriever with a No. 1 Ethibond suture is then passed into the joint and pulled outside the AM portal using a rotator cuff grasper. It is important to check that no synovial tissue is present between the sutures that have been pulled through the AM portal. The sutures are then retrieved through the joint and the transtibial tunnel using the Ethibond loop as a shuttle. The reducibility and the correct position of the MMPR are checked. The 4 tails of the 2 sutures are then passed through the Arthrex Biceps Button to create the configuration shown in Figure 9. This will allow the surgeon to apply constant tension to the suture without loosening. The tibial periosteum nearby the tunnel is elevated, and a 3.2-mm unicortical hole is drilled 2 cm below the transtibial tunnel. The tension must be maintained while inserting the button through the cortex to ensure the correct flip of the button under the tibial cortex. Pulling the free tails of the sutures, the surgeon progressively tightens the system, always arthroscopically checking the root tensioning with a probe. Once the desired tension is achieved and the knee is cycled through full range of motion to confirm the stability of the repair, 3 knots are tied with the different suture limbs. Patient in supine position, right knee, arhtroscopic view from standar AL portal.
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pmcMeniscal roots are an extension of the circumferential collagen fibers that run at the periphery of the meniscal body and represent a fundamental connection of such structures to the tibial plateau. Their integrity is fundamental for meniscal biomechanical purposes especially in absorbing the axial load and resisting pullout forces.1,2 Biomechanical studies, in fact, have shown that medial meniscus posterior root tears (MMPRTs) result in a complete loss of hoop strain resistance, which is comparable to a total meniscectomy.1,2 The detrimental effect of such lesions is nowadays well-known, with a dramatic increase in peak cartilage stress and, thus, chondral and subchondral lesions, which ultimately could result in a rapid onset of osteoarthritis (OA).3 Moreover, a recent matched-cohort study has shown the importance of MMPRT repair in preventing OA progression compared with partial meniscectomy or nonoperative treatment.4 For these reasons, different techniques has been implemented to repair MMPRTs.5 The transtibial techniques, both with double tunnels and with a single tunnel, are the most anatomic, thus resulting in procedures that more closely resemble the native meniscal root function.5 In addition, the suture type, whether simple or modified Mason-Allen stitches, has been investigated, resulting in the latter being the most effective in terms of healing rate, meniscal extrusion restoration, and reduction of OA progression.6 In studies that have examined the repair strength of various fixation methods used for meniscal root tears, it has been concluded that none of the repair methods restore the pullout strength of the insertions to the preinjury state,7,8 highlighting the importance of adequate fixation.

There is no clear evidence about the type of tibial fixation. In different cohort studies, both cortical buttons and screws with washers have been used, and in the case of a double tibial tunnel the repair could be secured by tying the sutures over the two bone tunnels bridge.9 Undoubtedly, because the medial meniscus posterior root (MMPR) needs to overcome extrusion forces, the tibial fixation device needs to couple the possibility of being sufficiently tight without losing tension. For these reasons, we present a simple and reproducible MMPRT transtibial repair technique using a subcortical fixation button already used as secondary cortical fixation in anterior cruciate ligament reconstruction and for subcortical long head biceps tenodesis.10

Technique

A standard anterolateral arthroscopic portal is placed to explore the entire joint and decide the best position for the anteromedial (AM) portal, which is placed under direct visualization. The medial compartment is explored while valgus stress is applied. The medial meniscus is palpated with a probe, and the integrity of the whole meniscal body and posterior root is check (Fig 1). If an MMPRT is present, we recommend performing “pie-crusting” of the superficial medial collateral ligament to open the compartment and avoid damage to the cartilage during the procedure.Fig 1 The medial meniscus posterior root (MMPR) is palpated with a probe, and the integrity is checked. Patient in supine position, right knee, arhtroscopic view from standar AL portal. (PCL, posterior cruciate ligament.)

The detached root is grasped and pulled in the direction of its anatomic insertion to check its reducibility. The remnant of the root attached to the bone and surrounding cartilage is debrided to expose the subchondral bleeding bone, which is fundamental for the integration of the repaired root in the recovery period.

A suture-passing device (Mini-First Pass; Smith & Nephew, Andover, MA) previously loaded with a No. 2 Ultrabraid suture (Smith & Nephew) is used to pass the first suture in the MMPR in the most medial aspect from the tibial to femoral side in a loop configuration. The loop is retrieved outside the AM portal with a rotator cuff grasper. The suture tails are passed through the loop and pulled to close the knot on the meniscal body. A second No. 2 Ultrabraid suture of a different color is passed through the meniscus in the same manner.

A 2- to 3-cm incision is performed in the anterolateral aspect of the tibia. The tibialis anterior fibers are smoothly dissected to reach the tibial periosteum, which is gently elevated. A low-profile tibial guide is positioned over the debrided root to reproduce its anatomic footprint (Fig 2), and a transtibial meniscal root repair device (Smith & Nephew), made of a 4.5-mm cannula over a guidewire, is drilled into the joint (Fig 3).Fig 2 Low-profile tibial guide positioned over debrided root to reproduce its anatomic footprint. Patient in supine position, right knee, arhtroscopic view from standar AL portal. (MMPR, medial meniscus posterior root.)

Fig 3 A 4.5-mm tibial tunnel is drilled into the anatomic footprint of the medial meniscus. Patient in supine position, right knee, arhtroscopic view from standar AL portal. (MMPR, medial meniscus posterior root.)

The tibial guide is removed, and the cannula is gently hammered into the joint. It is important to check if arthroscopic solution is now coming out of the cannula; this will mean that no drilled bone is present and the further steps can be performed.

A suture retriever with a No. 1 Ethibond suture (Ethicon, Somerville, NJ) is then passed into the joint and pulled outside the AM portal using a rotator cuff grasper. It is important to check that no synovial tissue is present between the sutures that have been pulled through the AM portal. The MMPR sutures are then retrieved through the joint and the transtibial tunnel using the Ethibond loop as a shuttle (Fig 4, Fig 5, Fig 6, Fig 7, Fig 8). The reducibility and the correct position of the MMPR are checked.Fig 4 Two nonabsorbable No. 2 high-resistance sutures are passed through the medial meniscus posterior root and retrieved outside the joint. Patient in supine position, right knee, arhtroscopic view from standar AL portal.

Fig 5 A No. 2 Vicryl suture (Ethicon) is pulled inside the tibial tunnel into the joint and is retrieved outside the joint. Patient in supine position, right knee, arhtroscopic view from standar AL portal. (MMPR, medial meniscus posterior root.)

Fig 6 The medial meniscus posterior root (MMPR) sutures are pulled outside the joint through the tibial tunnel. Patient in supine position, right knee, arhtroscopic view from standar AL portal.

Fig 7 The 2 medial meniscus posterior root sutures are divided based on color. Patient in supine position, right knee, arhtroscopic view from standar AL portal.

Fig 8 With the use of the Arthrex Biceps Button-specific needle, the 4 tails of the medial meniscus posterior root sutures are passed through the button.

The 4 tails of the 2 sutures are then passed through the Arthrex Biceps Button, as shown in Video 1, to create the configuration shown in Figure 9. This will allow the surgeon to apply constant tension to the suture without its loosening.Fig 9 (A, B) The sutures coming from the medial meniscus posterior root are passed in the configuration shown, allowing constant tensioning of the sutures without loosening. Patient in supine position, right knee, arhtroscopic view from standar AL portal.

The tibial periosteum nearby the tibial tunnel is gently elevated, and a 3.2-mm unicortical hole is drilled 2 cm below the transtibial tunnel (Fig 10). The tension must be maintained while inserting the button through the cortex and to ensure the correct flip of the button under the tibial cortex (Fig 11). Pulling the free tails of the sutures, the surgeon progressively tightens the system, always arthroscopically checking the MMPR tensioning with a probe (Figs 12 and 13). Once the desired tension is achieved and the knee is cycled through full range of motion to confirm the stability of the repair, 3 knots are tied with the different suture limbs.Fig 10 A 3.2-mm unicortical hole is drilled 2 cm below the transtibial tunnel. The sutures coming from the medial meniscus posterior root have been passed in a specific configuration that allows constant tensioning of the sutures without loosening. Patient in supine position, right knee, arhtroscopic view from standar AL portal.

Fig 11 The button is inserted and impacted into the unicortical tibial hole while tension is maintained on the sutures. Patient in supine position, right knee, arhtroscopic view from standar AL portal.

Fig 12 The the implant handle of the button is removed; the button is deployed in a subcortical manner, and pulling the free tails of the sutures allows the correct flip of the button. Patient in supine position, right knee, arhtroscopic view from standar AL portal.

Fig 13 The sutures are tensioned progressively under an arthroscopic view. Patient in supine position, right knee, arhtroscopic view from standar AL portal. (MMPR, medial meniscus posterior root.)

A step-by-step summary of our technique is provided in Table 1. Pearls and pitfalls of performing this surgical procedure are listed in Table 2.Table 1 Step-by-Step MMPR Transtibial Pullout Repair With Progressively Tensioning Subcortical Fixation Button

1. The patient is placed in the supine position on the operating table. A well-padded high-thigh tourniquet is subsequently placed on the operative leg.

	
2. A standard AL arthroscopic portal is placed to explore the entire joint and decide the best position for the AM portal, which is placed under direct visualization.

	
3. If an MMPR tear is present, pie crusting of the superficial medial collateral ligament is performed to open the compartment.

	
4. The detached root is grasped and pulled in the direction of its anatomic insertion to check its reducibility. The remnant of the root attached to the bone and surrounding cartilage is debrided to expose the subchondral bleeding bone.

	
5. A suture-passing device previously loaded with a No. 2 Ultrabraid suture is used to pass the first suture in the posterior root’s most medial aspect from the tibial to femoral side in a loop configuration.

	
6. The loop is retrieved outside the AM portal with a rotator cuff grasper. A second Ultrabraid suture of a different color is passed through the meniscus in the same manner.

	
7. A low-profile tibial guide is positioned over the debrided root, and a 4.5-mm cannula over a guidewire is drilled into the joint. The tibial guide is removed, and the cannula is hammered into the joint. A suture retriever with a No. 1 Ethibond suture is passed into the joint and pulled outside the AM portal.

	
8. The sutures are retrieved through the joint and the transtibial tunnel using the Ethibond loop as a shuttle.

	
9. The 4 tails of the 2 sutures are passed through the Biceps Button, and a 3.2-mm unicortical hole is drilled 2 cm below the transtibial tunnel.

	
10. The button is inserted through the cortex. Pulling the free tails of the sutures, the surgeon progressively tightens the system, always arthroscopically checking the root tensioning with a probe.

	
11. Once the desired tension is achieved and the knee is cycled through full range of motion to confirm the stability of the repair, 3 knots are tied with the different suture limbs.

	
AL, anterolateral; AM, anteromedial; MMPR, medial meniscus posterior root.

Table 2 Pearls, Pitfalls, and Risks

Pearls	
 Pie crusting of the superficial medial collateral ligament should be performed to open the compartment and avoid cartilage damage.	
 With a grasper, the surgeon should pull the detached root in the direction of its anatomic insertion to check its reducibility.	
 The tibialis anterior fibers are dissected to reach the tibial periosteum, which is elevated.	
 When the 4.5-mm cannula is drilled into the joint, the surgeon should check if arthroscopic solution is now coming out of the cannula; this will mean that no drilled bone is present and the further steps can be performed.	
 The surgeon should check that no synovial tissue is present between the sutures that have been pulled through the AM portal.	
 The tension must be maintained while inserting the button through the cortex to ensure the correct flip of the button under the tibial cortex.	
Pitfalls and risks	
 If the button is placed near the tibial tunnel, there is a risk of cortical failure.	
 More strands are unlikely to pass through the button.	
 If opposing ends are passed through the same side of the button, fixation may be affected.	
 If the sutures are the same color, it will be unclear which to tie together.	
 If cancellous bone is present, the button may not flip.	
 Twisting the inserter may bend the threaded tip, causing it to break inside the button.	
AM, anteromedial.

Discussion

MMPRTs can be due to acute trauma in young patients but commonly occur in middle-aged subjects in initial degenerative settings.11 Under these conditions, partial meniscectomy has been shown to lead to detrimental effects in terms of the cartilage status, as compared with nonoperative treatment, even with quite an improvement in symptoms. Surgical transtibial pullout repair, on the contrary, has been shown to improve clinical outcomes and, at least at short-term follow-up, reduce OA progression.12,13 Different surgical options have been implemented and highlighted in a recent systematic review on transtibial pullout repair.5 The unsatisfactory outcomes regarding healing rates and meniscal extrusion could be a result of the weak pullout strength offered by the repair techniques (cortical buttons and screws with washers).5 For these reasons, we have implemented a different tibial fixation method based on a subcortical button, originally developed for distal humeral biceps tendon fixation and recently used for secondary tibial anterior cruciate ligament fixation.10 The subcortical fixation device has the advantage of being a progressively tensioning device that can be constantly checked arthroscopically to directly visualize its effect on the MMPR. Such a device, in addition, does not have the risk of losing tension during suturing of the knots above the button or after the procedure, owing to its specific configuration.

Another advantage of the aforementioned device used in this setting is its very low profile on the tibial cortex, practically abolishing the risk of periosteal or subcutaneous inflammation. A list of advantages and limitations of our procedure can be found in Table 3. In our opinion, such a technique could be routinely and effectively used in the setting of MMPRT repair.Table 3 Advantages and Limitations

Advantages	
 Simple, safe, reproducible technique	
 Small size of drilled hole (3.2 mm)	
 Minimal hardware prominence	
 Suture configuration in button allows surgeon to apply constant tension to suture without loosening	
Limitations	
 Minimal displacement and excellent strength in proximal subpectoral biceps tenodesis; unknown biomechanical strength in root tear fixation	
 Technique supports use of only 4 strands of No. 2 Ultrabraid	

In conclusion, this technical note describes a surgical approach to MMPRT transtibial pullout repair using an adjustable subcortical fixation device. Further prospective clinical study needs to be conducted to verify the aforementioned advantages in daily practice from both a clinical point of view and a cost-effectiveness point of view.

Disclosures

All authors (S.P., N.P., M.G., M.I., R.M.A., R.T.C., J.C.M.,) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Supplementary Data

Video 1

Medial meniscus posterior root (MMPR) transtibial pullout repair with progressively tensioning subcortical fixation button. A standard anterolateral arthroscopic portal is placed to explore the entire joint and decide the best position for the anteromedial (AM) portal, which is placed under direct visualization. The medial compartment is explored while valgus stress is applied. The medial meniscus is palpated with a probe, and the integrity of the whole meniscal body is checked. If an MMPR tear is present, pie crusting of the superficial medial collateral ligament is performed to open the compartment. The detached root is grasped and pulled in the direction of its anatomic insertion to check its reducibility. The remnant of the root attached to the bone and surrounding cartilage is debrided to expose the subchondral bleeding bone. A suture-passing device previously loaded with a No. 2 Ultrabraid suture is used to pass the first suture in the posterior root’s most medial aspect from the tibial to femoral side in a loop configuration. The loop is retrieved outside the AM portal with a rotator cuff grasper. A second Ultrabraid suture of a different color is passed through the meniscus in the same manner. A 2- to 3-cm incision is performed at the anterolateral aspect of the tibia. The tibialis anterior fibers are smoothly dissected to reach the tibial periosteum, which is gently elevated. A low-profile tibial guide is positioned over the debrided root to reproduce its anatomic position, and a transtibial meniscal root repair device, composed of a 4.5-mm cannula over a guidewire, is drilled into the joint. The tibial guide is removed, and the cannula is gently hammered into the joint. It is important to check if arthroscopic solution is now coming out of the cannula; this will mean that no drilled bone is present and the further steps can be performed. A suture retriever with a No. 1 Ethibond suture is then passed into the joint and pulled outside the AM portal using a rotator cuff grasper. It is important to check that no synovial tissue is present between the sutures that have been pulled through the AM portal. The sutures are then retrieved through the joint and the transtibial tunnel using the Ethibond loop as a shuttle. The reducibility and the correct position of the MMPR are checked. The 4 tails of the 2 sutures are then passed through the Arthrex Biceps Button to create the configuration shown in Figure 9. This will allow the surgeon to apply constant tension to the suture without loosening. The tibial periosteum nearby the tunnel is elevated, and a 3.2-mm unicortical hole is drilled 2 cm below the transtibial tunnel. The tension must be maintained while inserting the button through the cortex to ensure the correct flip of the button under the tibial cortex. Pulling the free tails of the sutures, the surgeon progressively tightens the system, always arthroscopically checking the root tensioning with a probe. Once the desired tension is achieved and the knee is cycled through full range of motion to confirm the stability of the repair, 3 knots are tied with the different suture limbs. Patient in supine position, right knee, arhtroscopic view from standar AL portal.
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References

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