Arthroscopic Anatomic Repair of Lateral Meniscal Posterior Root Tears with All-Suture Anchors using Percutaneous Exchange Rod Technique Through High Posterolateral Portal

Abstract

Meniscal posterior root tears disrupt knee joint mechanics and can lead to early-onset osteoarthritis if untreated. Surgical repair is crucial to restore meniscal integrity, yet challenges remain, including achieving anatomical fixation, reducing neurovascular risks, and avoiding growth plate interference in young patients. Traditional transtibial pullout repair for medial meniscal posterior root tear is less biomechanically effective than suture anchor techniques, while conventional posteromedial portal approaches for anchor placement have risks. Repairing lateral meniscal posterior root tears in adolescents is even more challenging due to concerns about physeal damage and peroneal nerve proximity. We present an arthroscopic technique for meniscal root repair applicable to both medial and lateral tears, utilizing a single high posterolateral portal. It features 2 key innovations: the percutaneous exchange rod technique for accurate portal localization, enhancing minimally invasive access and reducing peroneal nerve injury risk, and the use of all-suture anchors for fixation, minimizing hardware-related cartilage trauma while ensuring biomechanical stability. This technique enables anatomical reattachment without transosseous tunnels, making it suitable for adult patients with medial meniscal posterior root tear and adolescents with lateral meniscal posterior root tear.

Meniscal posterior root tears, particularly those affecting the posterior roots of the medial and lateral meniscus, represent critical injuries that disrupt knee joint mechanics and predispose to early-onset osteoarthritis when untreated.¹ These tears compromise the meniscus’s load-distributing function, leading to altered tibiofemoral contact pressures and progressive cartilage degeneration.² While surgical repair is essential to restore meniscal integrity, challenges persist in achieving anatomical fixation, minimizing neurovascular risks, and avoiding growth plate interference in skeletally immature patients.

In adult populations, traditional transtibial pullout repair for medial meniscal posterior root tear (MMPRT) is widely used but are outperformed biomechanically by suture anchor techniques,^3,4 which offer superior stability and eliminate the “bungee effect”.⁵ However, conventional posteromedial portal approaches for anchor placement carry risks of saphenous nerve injury and suboptimal verticality relative to the anatomic footprint. For lateral meniscal posterior root tears (LMPRT) in adolescents, the challenge intensifies due to the need to avoid transosseous tibial tunnels (which risk physeal damage) and the proximity of the peroneal nerve to traditional repair portals.⁶

This technical note describes an arthroscopic technique for meniscal root repair—applicable to both medial and lateral tears—that addresses these limitations through a single high posterolateral portal (HPLP).^6,7 Central to this approach are 2 key advancements: (1) the use of percutaneous exchange rod technique for precision portal localization, which enhances minimally invasive access and reduces peroneal nerve injury risk by allowing arthroscopic visualization during portal creation; (2) the adoption of all-suture anchors for fixation, which minimizes hardware-related cartilage trauma while providing robust biomechanical stability. By leveraging the fibular head as an external landmark for safe HPLP placement and integrating these technical refinements, the technique ensures anatomical reattachment of the meniscal root without transosseous tunnels, making it suitable for both adult patients with MMPRT and adolescents with LMPRT. This technical note details the surgical steps, the clinical pearls, and outcomes of this method, highlighting its potential to advance meniscal root repair in diverse patient populations.

Surgical Technique

Step 1: Patient Setting, Portal and Preparation of LMPR

General or spinal anesthesia is administered. The patient is placed in the supine position with the operative knee (right knee) flexed at 90°. A high thigh pneumatic tourniquet is used for hemostasis. On the basis of the preoperative markings on the surgical knee, the standard anteromedial (AMP) and anterolateral (ALP) portals are established. The AMP is used as the observation portal and can be adjusted downward and positioned closer to the patellar tendon to provide better visualization of the lateral meniscal posterior root (LMPR). The ALP serves as the surgical portal and can be adjusted downward to facilitate safe passage of instruments beneath the lateral femoral condyle. Following meniscal repair, an accessory anterior median portal is established to facilitate suture management and instrument maneuverability (Fig 1A).

Fig 1.

Portals used in the LMPRT repair using exchange rod technique through HPLP. (A) The patient is placed in the supine position with the operative knee (right knee) flexed at 90°. The standard anterolateral and anteromedial portals are established, and an accessory anterior median portal is established to facilitate suture management and instrument maneuverability. (B) The high posterolateral portal is established ∼10-15 cm above the posterolateral joint line, positioned between the iliotibial band and biceps femoris tendon. A spinal puncture needle is advanced under arthroscopic guidance to confirm trajectory perpendicular enough to the target footprint. LMPRT, lateral meniscal posterior root tear; HPLP, high posterolateral portal.

The figure-4 position (hip flexed, abducted, and externally rotated with knee flexion) is used during the early diagnostic phase. Subsequent surgical maneuvers for LMPRT, including instrumentation and suture placement, are performed with the knee repositioned to the standard 90° flexed position.

A standard diagnostic arthroscopy is performed with 30° arthroscope. Initial diagnostic visualization is performed with the hip in a figure-4 position, optimizing exposure of the posterolateral compartment. Through the AMP, the torn edges of the LMPRT and footprint are debrided and decorticated with a burr to expose bleeding bone, ensuring optimal biologic healing. The knee is then repositioned to 90° flexion for definitive surgical management.

Step 2: Establishment of HPLP and Placement of All-Suture Anchor

The HPLP is established ∼10–15 cm above the posterolateral joint line, positioned between the iliotibial band and biceps femoris tendon (Fig 1B). During the operation, the operative knee is kept flexed at 90°, and the spinal needle is kept as close to the femur as possible. This is perceived to maintain a safe distance from the common peroneal nerve, thus significantly reducing the risk of nerve injury. Under 90° knee flexion, an 18-gauge spinal puncture needle is advanced under arthroscopic guidance to confirm trajectory perpendicular enough to the target footprint and proximity to the femur, ensuring a safe distance from the common peroneal nerve.

Following optimal needle placement, the inner stylet is replaced with a 1.0-mm Kirschner wire (K-wire), which is retained as an exchange rod upon needle withdrawal. The K-wire then directs the all-suture anchor cannula (Delta Medical, Beijing, China) to the target footprint without requiring additional portal dilation or deep-tissue separation (Fig 2, Fig 3). This exchange rod technique minimizes soft tissue disruption, preserves the original safety margin between instruments and neurovascular structures, and eliminates risks associated with repeated instrument passage. Then, a 1.8-mm V-lock all-suture anchor (Delta Medical) is placed through the guide device under direct visualization (Fig 3).

Fig 2.

Exchange rod technique in the anchor placement of LMPRT repair with all-suture anchor through HPLP. (A) The patient is placed in the supine position with the operative knee (right knee) flexed at 90°. Following optimal needle placement, the inner stylet is replaced with a 1.0-mm K-wire. (B) The K-wire serves as the exchange-rod after the remove of puncture needle. (C) The K-wire then directs all-suture anchor cannula to target footprint without requiring additional portal dilation or deep-tissue separation. LMPRT, lateral meniscal posterior root tear; HPLP, high posterolateral portal.

Fig 3.

The preparation of LMPRT and placement of all-suture anchor through HPLP. (A) The patient is placed in the supine position with the operative knee (right knee) flexed at 90°. The LMPR is identified through ALP. (B) The torn edges of the LMPR and footprint are debrided and decorticated with a burr to expose bleeding bone in a figure-4 position. (C) A rip-stop repair using all-inside meniscal repair device. (D) A spinal puncture needle is advanced through HPLP and the trajectory perpendicular enough to the target footprint is confirmed under arthroscopic guidance. (E) The all-suture anchor cannula is advanced into target footprint using exchange rod technique through HPLP without requiring additional portal dilation or deep-tissue separation. (F) A 1.8-mm V-lock all-suture anchor is placed through the guide device under direct visualization. LMPR, lateral meniscal posterior root; LFC, lateral femoral condyle; LTP, lateral tibial plateau; LMPRT, lateral meniscal posterior root tear; HPLP, high posterolateral portal.

Step 3: Suturing of Meniscal Tear

After anchor placement, the knee is positioned in a figure-of-4 configuration to expand the lateral compartment, optimizing arthroscopic visualization and suture manipulation. With the camera in the AMP, all 4 limbs are retrieved forward through ALP using a suture retriever.

The first suture hook is inserted ∼5 mm from the LMPRT, and the second hook is inserted approximately 10 mm from the LMPRT. Then, a polydioxanone suture (PDS) is introduced through the hook to guide the suture limbs (Fig 4, A-C). A key modification involves creating an accessory anteromedial portal to streamline suture management. The PDS-tractioned suture limb is initially retrieved through ALP and shuttled to the accessory anterior median portal using the suture retriever, minimizing tangling risks (Fig 4D).

Fig 4.

The suture of LMPRT using suture passer with all-suture anchor. (A) The patient is placed in the supine position with the operative knee (right knee) in a figure-of-4 configuration to expand the lateral compartment. The PDS suture is passed through the meniscus using a suture hook (blue arrow). (B) The first PDS suture is passed through the meniscus using a suture hook. (C) Two PDS sutures are passed through the meniscus using the suture hook ∼5 mm (yellow arrow) and 10 mm (red arrow) from the LMPRT. (D) The suture limbs are passed through the meniscus by PDS ∼5 mm (yellow arrow) and 10 mm (red arrow) from the LMPRT. (E) Paired sutures are tensioned and tied to reattach the root to its footprint from the accessory anteromedial portal (blue arrow). (F) The final configuration of the suture (blue arrow). LFC, lateral femoral condyle; LMPRT, lateral meniscal posterior root tear.

Once all sutures are positioned through the meniscal root, paired sutures are tensioned and tied in a sequential manner from the accessory anterior median portal, ensuring anatomical reattachment to the footprint. Suture ends are trimmed after confirming stable fixation (Fig 4, E and F) (Video 1).

Discussion

Meniscal root tears represent a critical challenge in orthopedic surgery, particularly in younger populations where the preservation of growth potential and long-term joint function is paramount. While transtibial pullout repair remains a widely adopted technique for restoring meniscal root integrity, its limitations—including risks of physeal injury in adolescents⁸ and the “bungee effect” leading to reduced biomechanical stability⁹—have driven the exploration of alternative approaches. Suture anchor repair has emerged as a promising solution, offering direct anatomic fixation without the need for transosseous tunnels. However, existing techniques often require complex portal placement, risking neurovascular injury or compromising visualization, especially in knees with intact ligaments.^10,11 This study introduces a modified arthroscopic technique for meniscal root repair that addresses these limitations using percutaneous exchange rod technique through HPLP.

Our technique builds on the principles outlined in recent literature, which emphasize anatomic restoration of the meniscal footprint and physeal-sparing strategies in skeletally immature patients. Boonyanuwat et al. demonstrated the efficacy of a single HPLP for lateral meniscal root repair in adolescents, leveraging the fibular head as an external landmark to minimize peroneal nerve injury.⁷ Similarly, Tian et al. highlighted the biomechanical advantages of knotless anchors inserted via HPLP for medial meniscal root repairs, achieving superior verticality and stability.⁶ Our approach synthesizes these advancements, using a single HPLP with exchange rod technique for both lateral and medial root repairs, thereby standardizing the procedure while accommodating anatomic variations.

A key innovation lies in the strategic portal placement, which avoids the need for accessory posteromedial portals that risk saphenous nerve injury or cartilage damage to the medial femoral condyle. By positioning the portal superior to the joint line and angling instrumentation toward the meniscal footprint, we achieve consistent vertical anchor placement without compromising the peroneal nerve or physis. This contrasts with traditional transtibial techniques, where tunnel convergence with concurrent ACL reconstruction remains a concern. During the operation, the operative knee is kept flexed at 90°, and the spinal needle is kept as close to the femur as possible. This is perceived to maintain a safe distance from the common peroneal nerve, thus significantly reducing the risk of nerve injury. Besides, the use of percutaneous exchange rod technique further reduces the risk of common peroneal nerve injury because there is no need for dilation or debridement of posterior structures (Table 1).

Table 1.

Advantages and Disadvantages

Advantages

The HPLP minimizes neurovascular risks, while avoiding transosseous tunnels ensures physeal safety in adolescents.

Percutaneous exchange rod technique enhances precision and guarantees the verticality of anchor, reducing peroneal/saphenous nerve damage.

This technique does not affect simultaneous ligament reconstruction or high tibial osteotomy.

This technique has no bungee effect and provides great biomechanical outcomes.

Disadvantages

Establishing the HPLP can be challenging for less experienced surgeons.

There is a risk of peroneal nerve/vessel damage.

Biomechanically, our technique aligns with studies showing that suture anchor repair provides greater load-to-failure strength and cyclic stability compared to transtibial methods. The absence of a tibial tunnel not only preserves the physis but also mitigates the bungee effect, ensuring direct force transmission to the meniscotibial interface. This is particularly critical in adolescents, where even minor growth disturbances can lead to angular deformities.^8,12 Additionally, the simplified workflow—avoiding fluoroscopic guidance or hyperflexion positioning—enhances reproducibility, especially in combined procedures like ACL reconstruction or osteotomy (Table 2).

Table 2.

Pearls and Pitfalls

Pearls

Precise HPLP Placement: Use the fibular head as an external landmark and position the high posterolateral portal (HPLP) 10–15 cm above the posterolateral joint line, between the iliotibial band and biceps femoris tendon. This minimizes proximity to the common peroneal nerve.

Exchange Rod Technique: Utilize a 1.0-mm Kirschner wire (K-wire) to guide the all-suture anchor cannula, eliminating the need for portal dilation or deep tissue dissection. This preserves soft tissue integrity and reduces neurovascular disruption.

Physeal Safety in Adolescents: Avoid transosseous tunnels by using all-suture anchors, which eliminate risks of growth plate damage. Pair this with HPLP to bypass physeal regions.

Visualization Optimization: Use the figure-4 position for diagnostic arthroscopy and initial debridement to expose the posterolateral compartment; switch to 90° flexion for anchor placement and suturing.

Pitfalls

Peroneal Nerve Injury: Risk arises from improper portal placement or instrument trajectory. Caution: Keep the spinal needle and instruments close to the femur during HPLP establishment; use arthroscopic guidance to confirm a safe distance from the nerve. Maintain 90° knee flexion to stabilize neurovascular structures.

Inadequate Anchor Verticality: Poor trajectory may compromise fixation stability. Caution: Confirm needle trajectory is perpendicular to the target footprint under arthroscopic visualization before inserting the K-wire. Adjust the needle angle if needed to ensure optimal anchor placement.

Growth Plate Interference: Transosseous techniques risk physeal injury in skeletally immature patients. Caution: Strictly use suture anchors instead of tibial tunnels; reference preoperative imaging to identify physeal locations and adjust portal/instrument paths accordingly.

Inadequate Visualization of LMPR Footprint: May result in incomplete debridement or incorrect anchor placement. Caution: Adjust the anteromedial portal (AMP) downward near the patellar tendon to enhance visualization of the lateral meniscal posterior root (LMPR); use a 30° arthroscope for better angle coverage.

Despite these advantages, challenges persist. Precise portal establishment requires familiarity with posterolateral anatomy, and inadvertent distal placement risks peroneal nerve injury. However, our use of spinal needle localization and exchange rod technique minimized such risks. Furthermore, improper tension during anchor insertion may compromise fixation. Intraoperative stress testing ensures adequate stability before finalizing the repair.

Long-term outcomes must be evaluated to confirm the durability of this approach. While early studies on suture anchor repairs report favorable healing rates and functional recovery, concerns remain about anchor pullout in osteopenic bone or degenerative tears. Future research should compare outcomes across age groups and tear types, particularly in cases with severe meniscal extrusion requiring adjunctive centralization.

In conclusion, our technique offers a safe, physeal-sparing solution for meniscal root repair, combining the biomechanical benefits of suture anchors with simplified arthroscopic execution. By standardizing portal placement and instrumentation, it addresses the limitations of existing methods, while maintaining adaptability for complex cases. As meniscal preservation continues to evolve, this approach represents a viable option for optimizing outcomes in both adolescent and adult populations.

Disclosures

All authors (J.S., Z.J., T.L., X.D., R.L., Z.S., L.F.) 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

First, the standard anterolateral portal and anteromedial portal are established. With the hip in a figure-4 position, the torn edges of meniscal posterior root tears and its footprint are debrided and decorticated by using a burr through the anteromedial portal to expose bleeding bone. Then, an accessory anterior median portal is established to facilitate suture management and instrument maneuverability. Next, a single high posterolateral portal is created ∼10–15 cm above the posterolateral joint line, positioned between the iliotibial band and biceps femoris tendon, and the meniscal posterior root tear is identified and repaired through the anterolateral portal. With the knee flexed at 90°, an 18-gauge spinal puncture needle is advanced under arthroscopic guidance; the inner stylet is then replaced with a 1.0-mm Kirschner wire (K-wire), which is retained as an exchange rod when the needle is withdrawn. The all-suture anchor cannula is guided by the K-wire to the target footprint, and a 1.8-mm V-lock all-suture anchor is placed via the guide device. All 4 suture limbs are retrieved forward through the anterolateral portal using a suture retriever, after which the first suture hook and the second suture hook are inserted ∼10 mm and 5 mm from the lateral meniscal posterior root tears, respectively. Polydioxanone (PDS) sutures are introduced through the hooks to guide the suture limbs, which are then passed through the meniscus using the PDS sutures. Finally, paired sutures are tensioned and tied sequentially from the accessory anteromedial portal, and suture ends are trimmed after confirming stable fixation.