Suture Repair of Full Radial Posterior Lateral Meniscus Tears Using a Central Midline Portal

Arthroscopic Lateral Meniscus Root Repair With Reverse Suture Anchor Technique

The stability of the knee joint is crucially dependent on the integrity of the lateral meniscus posterior root, which is often accompanied by anterior cruciate ligament injury. Anchor suture repair for lateral meniscus posterior root injury not only achieves better biomechanical effects but also ensures favorable prognosis. However, the placement of anchors often requires the establishment of a posterior approach, and the insertion of an anchor is a technical challenge. In light of this, we have applied the technique of reverse anchor fixation for repairing the lateral meniscus posterior root, which not only simplifies the procedure but also effectively reduces the "bungee effect."

Evaluation of the All-Inside Technique for the Repair of Lateral Meniscus Root Tears at 1 Year After ACL Reconstruction

Background

The presence of a lateral meniscus root tear (LMRT) in patients with an anterior cruciate ligament (ACL) tear makes the knee more unstable and increases the risk of osteoarthritis and osteonecrosis. An all-inside suture repair technique without bone tunnels has been proposed to treat LMRT.

Purpose

To compare the 1-year postoperative findings between patients who underwent ACL reconstruction combined with LMRT repair (LMRT group) and patients who underwent isolated ACL reconstruction (control group).

Study Design

Cohort study; Level of evidence, 3.

Methods

The LMRT group consisted of 19 patients, and the control group consisted of 56 patients. In this study, the authors compared the postoperative magnetic resonance imaging (MRI) findings (meniscal extrusion, ghost sign, and hyperintensity in the tibial plateau beneath the LMRT), functional outcomes (International Knee Documentation Committee [IKDC], Lysholm, and Tegner scores), and reoperation rate between groups. The primary endpoint was analyzed by comparing, in the LMRT group, the 1-sided 97.5% confidence interval (CI) of the mean lateral meniscal extrusion at 1 year to the limit of noninferiority (fixed at 0.51). To take into account imbalanced baseline characteristics between groups, adjusted mean meniscal extrusion (with 1-sided 97.5% CI) was assessed using a linear regression model.

Results

The mean follow-up was 12.2 months (range, 7.7-14.7 months) in the control group and 11.5 months (range, 7.1-13.0 months) in the LMRT group (P = .06). For meniscal extrusion, the LMRT group was noninferior to the control group. The mean meniscal extrusion was 2.19 mm (97.5% CI, -infinity to 2.68 mm) in the LMRT group and 2.03 mm (97.5% CI,-infinity to 2.27 mm) in the control group, indicating that the upper boundary of the 1-sided 97.5% CI in the LMRT group was less than the noninferiority threshold of 2.78 (ie, 2.27 mm + 0.51 mm = 2.78 mm). There was a statistically significant difference in the IKDC score between the LMRT and control groups (77.2 ± 8.1 vs 80.3 ± 7.3, respectively; P = .04). There was no between-group difference in the other MRI parameters, the Lysholm and Tegner scores, or the reoperation rate.

Conclusion

There was no significant difference in extrusion on MRI or clinical outcomes at 1-year follow-up in patients who underwent ACL reconstruction with all-inside LMRT repair compared with patients who did not have an LMRT.

Low reoperation rate following lateral meniscus root repair: clinical outcomes at 2 years follow-up

PURPOSE

The aim of this study was to review the outcomes of lateral meniscus posterior root tears repair at the time of ACL reconstruction at a minimum 2-year follow-up.

METHODS

Between March 2015 and August 2018, 2017 patients underwent primary ACL reconstruction and were considered for study eligibility. Lateral meniscus posterior root tears were identified arthroscopically, and repair was performed with a transtibial pull-out suture technique or a side-to-side suture technique. Clinical outcomes were recorded at the time of physical examination. At the end of the study period, patients were contacted to determine whether they had required reoperation.

RESULTS

Lateral meniscus posterior root tears were identified in 153 out of the 2,017 primary ACL reconstructions (7.6%). Ninety-nine patients were included for analysis: 23 transtibial pull-out sutures and 76 side-to-side repairs. At a mean follow-up of 42 ± 10 months, one patient (1%) had undergone reoperation for failure of the side-to-side repair. There were 11 reoperations in 10 patients (10.1%), including 6 cyclops syndrome, 1 graft rupture, 1 tibial bone cyst, 1 medial and 1 lateral meniscus repair failure, and 1 arthrolysis. Postoperatively, ninety (90.9%) patients were graded A for the IKDC objective score and 9 (9.1%) patients were graded B, with an IKDC subjective score of 86.9 ± 7.6, a Lysholm score of 90.7 ± 6.7 and a median Tegner Activity Scale of 6 (3-9). All of their objective and subjective evaluations improved after surgery (p < 0.001) except for the Tegner Activity Scale. Ten patients underwent second look arthroscopy (10.1%), lateral meniscus healing was observed in 9 out of 10 patients (90%).

CONCLUSION

This study demonstrated that lateral meniscus posterior root tear repair is a safe procedure with a very low reoperation rate at a minimum follow-up of 2 years.

LEVEL OF EVIDENCE

IV.

Epidemiology of Combined Injuries of the Secondary Stabilizers in ACL-Deficient Knees: Medial Meniscal Ramp Lesion, Lateral Meniscus Root Tear, and ALL Tear: A Prospective Case Series of 602 Patients With ACL Tears From the SANTI Study Group

BACKGROUND

Medial meniscal ramp lesion (MMRL), lateral meniscus root tear (LMRT), and anterolateral ligament (ALL) tear are individual injuries that have been described in patients who have an anterior cruciate ligament (ACL) tear. However, the prevalence of these lesions and their combination has not been defined.

PURPOSES

To define the individual and combined prevalence of MMRL, LMRT, and ALL tears in a case series of patients undergoing ACL reconstruction and to identify the risk factors for combined injuries.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Patients aged >15 years undergoing primary ACL reconstruction between January 2019 and June 2021 were enrolled in the study. A preoperative ultrasound scan was performed to look for an ALL tear. The presence of MMRL and LMRT was determined during a standardized arthroscopy exploration. A multivariate logistic regression model was used to determine the individual effect of patient variables on the risk of associated single, dual, triad, or tetrad injuries (MMRL, LMRT, ALL, ACL), represented by an adjusted odds ratio.

RESULTS

The case series consisted of 602 patients who underwent primary ACL reconstruction. An isolated ACL injury was present in 147 patients (24%). A dual injury was detected in 34 patients (6%) who had ACL-MMRL, 16 (2.65%) who had ACL-LMRT, and 265 (44%) who had ACL-ALL. A triad injury was detected in 80 patients (13.28%) who had ACL-ALL-MMRL, 36 (6%) who had ACL-ALL-LMRT, and 3 (0.5%) who had ACL-MMRL-LMRT. A tetrad injury pattern was detected in 21 patients (3.5%). Multivariate analysis showed that the occurrence of tetrad injury was significantly lower in older patients (adjusted odds ratio by year, 0.93 [95% CI, 0.88-0.99]; P = .028). Identifying LMRT increased the likelihood of finding MMRL-ALL injuries by 2.11 times (95% CI, 1.09-3.12; P = .031).

CONCLUSION

Isolated ACL tear is less common than combined injuries, which are quite frequent. Younger age is a risk factor for combined injuries. The search for damaged secondary stabilizers of the knee must be meticulous and systematic, especially when 1 injured structure has already been diagnosed.

Arthroscopic Repair of Posterior Root Tears of the Lateral Meniscus with All-Suture Anchor

Meniscus root tears are increasingly being recognized and treated because of improved awareness and diagnostics. These injuries commonly occur in combination with knee ligament injuries. Untreated posterior meniscus root teats have been demonstrated to increase contact pressure and decrease contact area, ultimately leading to unfavorable joint loading and development of early osteoarthritis. Posterior lateral meniscus root tears (PLMRTs) also have been reported to increase anterior tibial translation and pivot shift in anterior cruciate ligament-deficient knees. Therefore, it is crucial to repair meniscal root tears when possible to restore knee joint loading and kinematics. Several techniques for repair of the PLMRT have been described. In this Technical Note, we describe our preferred technique for repair of PLMRT using an all-suture anchor. This technique is reproducible, does not need a tunnel, mitigates bungee effect of transtibial technique, and the anchor can easily be inserted on the footprint without a need for a guide.

All-Inside Double-Sided Suture Repair for Longitudinal Meniscal Tears

The current consensus in the literature is that the meniscus must be saved. Even though inside-out sutures are still considered as the gold standard, the need to alternate between intra- and extra-articular structures for every stitch makes it laborious. New generations of all-inside systems are now routinely used in operating rooms and enable easier, quicker, and safer techniques. However traditional all-inside repair with limited upper fixation does not provide uniform compression from top to down, essential precondition for satisfactory meniscal healing. This Technical Note describes a simple and accessible alternative technique that provides stable fixation and overall compression of vertical meniscal tears from top to down with standard all-inside instrumentation.

Central patellar portal placement frequently provokes anterior knee compartment radiological abnormalities in anterior cruciate ligament reconstruction

PURPOSE

A central patellar (CP) portal can be used to view the native femoral insertion site of the anterior cruciate ligament (ACL). It aids in the drilling of an anatomical tunnel; however, its impact on the patellar tendon and the infrapatellar fat pad remains a concern. The aim of this study was to investigate complications associated with the CP portal use in arthroscopic ACL reconstruction (ACLR).

METHODS

A total of 105 patients (107 knees, 60 females) who underwent ACLR with a CP portal from 2012 to 2017 were included in this study. The mean age was 28.3 ± 12.4 years. All surgeries were single-bundle reconstructions using the trans-tibial technique via the CP and anteromedial portals. Post-operative events, magnetic resonance imaging (MRI), and arthroscopic findings associated with CP portal creation were evaluated.

RESULTS

Five patients (4.7%) had symptomatic postoperative complications, which included two patients with patellar tendonitis and three patients with fibrosis in the anterior knee compartment. Abnormal signal intensity of the patellar tendon on MRI and increased thickness at the CP portal area were found in 18 of 25 knees (72%). Three of 56 knees (5.4%) that underwent second-look arthroscopy showed fibrosis of the infrapatellar fat pad. Seven patients (12.5%) showed hypertrophy of the ligamentum mucosum.

CONCLUSIONS

The rate of symptomatic complications associated with CP portal placement was 4.7%; however, abnormal MRI or follow-up arthroscopy findings were much higher than clinically symptomatic patients. This study suggests that CP portal placement could provoke anterior knee compartment fibrosis or hypertrophy.

LEVEL OF EVIDENCE

IV.

Arthroscopic side-to-side repair for complete radial posterior lateral meniscus root tears

BACKGROUND

The aim of this study was to determine the radiographic, second-look, and functional outcomes after arthroscopic side-to-side repair for complete radial posterior lateral meniscus root tears (PLMRTs).

METHODS

Patients who underwent arthroscopic side-to-side repair for complete radial PLMRTs were identified. Clinical assessment consisted of symptoms (locking, catching, giving way and effusion), examinations of joint-line tenderness and McMurray test, and subjective scores of International Knee Documentation Committee (IKDC), Lysholm, and Tegner. In addition, postoperative MRI scan and second-look arthroscopy were performed to assess the healing status of the repaired meniscus.

RESULTS

Twenty-nine patients met the inclusion criteria. The mean age was 25.41 years. The mean follow-up period was 26.68 months. During the follow-up, none of the patients had symptoms of meniscal retear, lateral joint-line tenderness or a positive McMurray test. The postoperative subjective scores of IKDC, Lysholm, and Tegner improved significantly compared to the preoperative values (P = 0.01). Postoperative MRI scan showed that 28/29 (96.6%) patients achieved meniscus healing. Twenty-two patients underwent second-look arthroscopy, among whom 19 (86.4%) patients showed complete meniscus healing and 3 (13.6%) patients showed partial healing.

CONCLUSION

Arthroscopic side-to-side repair was a valuable surgical repair technique for complete radial PLMRTs, which leaded to significant improvements in both objective and subjective functional outcomes with a high rate of meniscus healing.

LEVEL OF EVIDENCE

Level IV, case series.

All-Inside Lateral Meniscal Repair via Anterolateral Portal Increases Risk of Vascular Injury: A Cadaveric Study

PURPOSE

To compare the distance from the device tip to the neurovascular structures during an all-inside medial and lateral meniscal repair using anteromedial and anterolateral portals in a fresh-frozen cadaveric study.

METHODS

Ten fresh-frozen cadaveric knees were studied. The popliteal artery, popliteal vein, and tibial nerve were identified after dissection via a posterior approach. An all-inside meniscal repair device was set to a 20-mm depth limit and inserted into a fixed point in the posterior horn at the meniscocapsular junction. This was performed for medial and lateral menisci via anteromedial and anterolateral arthroscopic portals. The distances between the device tip and the neurovascular structures were measured. We performed t tests to determine statistical significance.

RESULTS

The distance between the device and popliteal artery was significantly closer when aimed at the posterior horn of the lateral meniscus via the anterolateral portal (4.7 ± 2.3 mm) versus the anteromedial portal (13.0 ± 8.0 mm, P = .010). The distance to the popliteal vein was closer via the anterolateral portal (6.7 ± 2.9 mm) versus the anteromedial portal (13.9 ± 5.8 mm, P = .004). For medial meniscal repair, the distance to the popliteal artery was significantly closer via the anteromedial portal (12.8 ± 11.3 mm) versus the anterolateral portal (23.8 ± 7.7 mm, P = .022). The distance to the popliteal vein was closer via the anteromedial portal (16.5 ± 11.3 mm) versus the anterolateral portal (28.3 ± 8.2 mm, P = .017). No significant difference was found in the distance to the tibial nerve when aimed at either meniscus via either portal.

CONCLUSION

For all-inside meniscal repair, the popliteal vein is at risk and the popliteal artery is at high risk of injury when the posterior horn of the lateral meniscus is repaired via an anterolateral working portal.

CLINICAL RELEVANCE

The popliteal artery and vein are at risk of injury when the posterior horn of the lateral meniscus undergoes all-inside repair via the anterolateral portal. Surgeons need to be aware of the risks when performing this repair.

Proximity of the Neurovascular Bundle During Posterior-Lateral Meniscal Repair: A Comparison of the Transpatellar, Anteromedial, and Anterolateral Portals

PURPOSE

To compare the neurovascular proximity of the transpatellar portal with that of the medial and lateral portals and to determine the safe penetration depth for an all-inside device for use on the posterior horn lateral meniscus.

METHODS

Dissection of the popliteal fossa was performed in 10 cadaveric knees to identify all structures. Arthroscopy was performed using penetration depths of 10, 12, 14, and 16 mm with the all-inside system through the anteromedial, anterolateral, and transpatellar portals. Penetrations were made 5 and 10 mm lateral to the posterior horn root at the meniscocapsular junction. Needle-tip distances were measured from the popliteal artery and vein, tibial nerve, and common peroneal nerve.

RESULTS

Among 240 trials, the average distance to the popliteal neurovascular bundle using the medial, transpatellar, and lateral approaches was 6.9 mm, 6.5 mm, and 3.1 mm, respectively. The transpatellar-portal needle had a larger distance from the neurovascular bundle than the lateral portal (P = .001), with no statistical difference compared with the medial portal (P = .58). Compared with the position at a 10-mm distance from the root, the position at a 5-mm distance from the root was closer to the neurovascular bundle in all approaches (P = .001). The transpatellar approach set to 14 mm had a 5% rate of capsular underpenetration and 10% rate of gastrocnemius penetration. The transpatellar and medial portals had no neurovascular penetrations, whereas the lateral approach had a 14% rate of penetration (P < .05).

CONCLUSIONS

The transpatellar portal and anteromedial portal are in less proximity to the neurovascular bundle compared with the anterolateral portal for all-inside meniscal repair of the posterior horn lateral meniscus. Low rates of neurovascular penetration, gastrocnemius muscle penetration, and capsular underpenetration occurred with a depth setting of 14 mm.

CLINICAL RELEVANCE

This study shows the utility of medial and transpatellar portals when using all-inside devices to repair posterior horn lateral meniscal tears and neurovascular proximity based on penetration depth.

Risk Factors for Lateral Meniscus Posterior Root Tears in the Anterior Cruciate Ligament-Injured Knee: An Epidemiological Analysis of 3956 Patients From the SANTI Study Group

BACKGROUND

Lateral meniscus posterior root tears (LMPRTs) result in loss of hoop forces and significant increases in tibiofemoral contact pressures. Preoperative imaging lacks reliability; therefore, holding an appropriate index of suspicion, based on the epidemiology of and risk factors for LMPRT, may reduce the rate of missed diagnoses.

PURPOSE

The primary objectives of this study were to evaluate the incidence of and risk factors for lateral meniscus root lesions in a large series of patients undergoing anterior cruciate ligament (ACL) reconstruction.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

All patients who underwent primary or revision ACL reconstruction by a single surgeon between January 2011 and April 2018 were considered for study eligibility. From this overall population, all patients who underwent repair of an LMPRT were identified. The epidemiology of LMPRT was defined by the incidence within the study population, stratified by key demographic parameters. Potentially important risk factors for the presence of LMPRT were evaluated in multivariate logistic regression analysis.

RESULTS

A total of 3956 patients undergoing ACL reconstruction were included in the study. An LMPRT was identified and repaired in 262 patients (6.6%). Multivariate analyses demonstrated that significant risk factors for LMPRT included a contact sports injury mechanism (7.8% incidence with contact sport mechanism vs 4.5% with noncontact mechanism; odds ratio, 1.69; 95% CI, 1.266-2.285; P < .001) and the presence of a medial meniscal tear (7.9% incidence with medial meniscal tear vs 5.8% without; odds ratio, 1.532; 95% CI, 1.185-1.979; P < .001). Although the incidence of LMPRT in male patients (7.3%) was higher than in females (4.8%), this was not significant in multivariate analysis ( P = .270). Patient age, revision ACL reconstruction, and a preoperative side-to-side laxity difference ≥6 mm were not significant risk factors for LMPRT.

CONCLUSION

The incidence of LMPRT was 6.6% in a large series of patients undergoing ACL reconstruction. Participation in contact sports and the presence of a concomitant medial meniscal tear were demonstrated to be important independent risk factors. Their presence should raise the index of suspicion for this injury pattern.