Outcomes of Combined Lateral Meniscus Posterior Root Repair and Anterior Cruciate Ligament Reconstruction

Meniscus root tears: what is the hype?

ABSTRACT

Meniscus root tears are increasingly being studied due to their importance in meniscus function. Meniscus root tears can increase the joint contact pressure significantly, similar to a total meniscectomy. This may cause rapid progression of joint degeneration and produce inferior clinical outcome. Historically, they were treated with partial meniscectomy, which did not change the natural history. New repair techniques such as transtibial pull-out repair and suture anchor repair have improved the clinical outcome. This review article summarises the anatomy of the meniscus, the pathology of meniscus root tears and different repair techniques with their clinical outcomes.

Precision Anterior Cruciate Ligament Reconstruction

Precision anterior cruciate ligament reconstruction (ACLR) refers to the individualized approach to prerehabilitation, surgery (including anatomy, bony morphology, and repair/reconstruction of concomitant injuries), postrehabilitation, and functional recovery. This individualized approach is poised to revolutionize orthopedic sports medicine, aiming to improve patient outcomes. The purpose of this article is to provide a summary of precision ACLR, from the time of diagnosis to the time of return to play, with additional insight into the future of ACLR.

Male Sex, Revision Surgery, Low Volume of Anterior Cruciate Ligament Remnant, and Significant Instability Are Risk Factors for Posterior Root Tear of the Lateral Meniscus in Patients Undergoing Anterior Cruciate Ligament Reconstruction

PURPOSE

To determine the incidence of lateral meniscus posterior root tears (LMPRTs) in patients undergoing anterior cruciate ligament (ACL) reconstruction and identify associated risk factors.

METHODS

We conducted a retrospective, multicenter study using data from the Francophone Arthroscopic Society's registry. The study included all the patients in the registry who underwent ACL reconstruction surgery between June 2020 and June 2023; we excluded incomplete data. We compared delay from injury to surgery between LMPRTs group and no-LMPRTs group. Variables investigated as potential risk factors for LMPRTs included age, sex, nature of surgery (primary or revision), pivot shift test result, side-to-side laxity under anesthesia, presence of ACL remnant, occurrence of medial meniscal tear, and presence of collateral ligament injury. Risk factors were analyzed using a logistic regression model.

RESULTS

Among the 5,359 patients analyzed, LMPRTs occurred in 7.0% (n = 375) of cases during ACL reconstruction. Mean age at surgery was 29.3 ± 10.3 years old [11-77]. Concerning delay to surgery, the mean time was 8.4 ± 23.1 weeks [0.0-347.2] in the no-LMPRTs group and 6.5 ± 10.2 weeks [0.2-61.6] in the LMPRTs group (P = .109). Univariate analysis revealed that male sex (P < .001), revision surgery (P < .001), medial meniscal injury (P = .007), ACL remnant (0% vs >70%, <10% vs >70%, 10%-30% vs >70%, >30%-50% vs >70%, >50%-70% vs >70%; P < .001), and greater pivot shift grade (P = .011) were significantly associated with a presence of LMPRTs. Age, side-to-side laxity, and collateral ligament injury were not found to be significant risk factors. In multivariate analysis, male sex, revision surgery, pivot shift test result, and a low volume of ACL remnant remained significant. Side-to-side laxity was also a significant factor in multivariate analysis.

CONCLUSIONS

This study identified male sex, revision surgery, low volume of ACL remnant, side-to-side laxity, and greater grade of pivot shift as significant risk factors for LMPRTs during ACL reconstruction.

LEVEL OF EVIDENCE

Level III, retrospective comparative case series.

A Convergent Tibial Tunnel Technique for Concomitant Anterior Cruciate Ligament Reconstruction and Meniscal Root Repair

Modern arthroscopic knee-reconstruction techniques involve the use of multiple bone tunnels and fixation devices to restore the anatomy and stability of the knee after traumatic injury. In these injuries, however, tunnel collision can be problematic, especially when combining anterior cruciate ligament reconstruction with meniscal root repairs or multiligament reconstructions. We describe a multiple tibial tunnel technique to allow fixation of both anterior cruciate ligament graft and meniscal roots through convergence to a single tibial cortical aperture.

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."

Single Bundle Anterior Cruciate Ligament With Anterolateral Ligament Reconstruction Yields Similar Clinical and Radiographic Results at Minimum 2-Year Follow-Up Versus Double Bundle Anterior Cruciate Ligament Reconstruction: A Prospective Randomized Controlled Trial

PURPOSE

To compare the clinical, radiographic, and second-look arthroscopic outcomes between double-bundle (DB) anterior cruciate ligament (ACL) reconstruction (DB group) and combined single-bundle (SB) ACL and anterolateral ligament (ALL) reconstruction (SB + ALL group) by a prospective randomized controlled trial.

METHODS

From May 2019 to June 2020, 84 patients were enrolled in this study. Among them, 10 were lost to follow-up. Thirty-six and 38 patients were successfully allocated to the DB (mean follow up 27.3 ± 4.2 months) and SB + ALL groups (27.2 ± 4.5 months), respectively. The preoperative and postoperative Lachman test, pivot shift test, anterior translation on stress radiographs, KT-2000 arthrometer, Lysholm score, International Knee Documentation Committee score, and Tegner activity score were evaluated and compared. Graft continuity was evaluated using postoperative magnetic resonance imaging (MRI) (32 and 36 patients underwent MRI in the DB and SB + ALL groups at 7.4 ± 3.2 and 7.5 ± 2.9 months after surgery, respectively), and second-look examinations (second-look examination and tibial screw removal were performed concomitantly when patients (1) had tibial screw-related irritation or (2) needed the screws removed, 28 and 23 patients underwent examinations in the DB and SB + ALL groups at 24.0 ± 6.8 and 24.9 ± 8.1 months after surgery, respectively). All measurements were compared between the groups.

RESULTS

Postoperative clinical outcomes significantly improved in both groups. (All variables showed P < .001) No statistically different outcomes were found between the 2 groups. Additionally, postoperative graft continuity on MRI and second-look examinations were not different between the 2 groups.

CONCLUSIONS

The DB and SB + ALL groups showed similar postoperative clinical, radiographic, and second-look arthroscopic outcomes. Both groups showed excellent postoperative stability and clinical outcomes compared with the preoperative measurements.

LEVEL OF EVIDENCE

Level II, randomized controlled trial.

Lateral meniscus posterior root repair in the setting of anterior cruciate ligament reconstruction restores joint mechanics to the intact state and improves clinical function: a systematic review of biomechanical and clinical outcomes

PURPOSE

To perform a systematic review of biomechanical and clinical outcomes following lateral meniscus posterior root (LMPR) repair with concomitant anterior cruciate ligament reconstruction (ACLR).

METHODS

A literature search was performed systematically using PubMed, Embase, and Medline databases in April 2022. The search included the following terms combined with Boolean operators: 'Meniscus repairs', 'Meniscal Repair', 'Posterior Horn', 'Root', 'Radial'. Inclusion criteria consisted of level I-IV human clinical and biomechanical studies reporting biomechanical data and/or outcomes following LMPR repair in the setting of ACLR.

RESULTS

Three biomechanical studies, all utilizing a transtibial pullout technique, were identified, all of which reported significant improvement in joint contact pressures and mechanics and 3/4 of which reported significant improvement in anterior or rotational stability with LMPR repair. Five clinical studies, consisting of 146 patients (mean age 28.5 ± 1.1 years) undergoing LMPR repair, were identified with an average follow-up of 19.1 months (range 6.2-46 months). Across all clinical studies, Lysholm and International Knee Documentation Committee (IKDC) scores were found to improve postoperatively, with 3/4 reporting significant improvement in Lysholm (all, p ≤ 0.001) scores and 3/5 reporting significant improvement in IKDC scores when compared to preoperative values (all, p ≥ 0.004). Meniscal extrusion decreased significantly following repair in 2/4 studies (all, p ≤ 0.001).

CONCLUSIONS

Biomechanically, transtibial pullout repair of the LMPR restored joint contact pressures and joint mechanics to intact levels when performed with concomitant ACLR. Clinically, LMPR repair with concurrent ACLR resulted in improved Lysholm and IKDC scores. These findings enable surgeons to determine optimal treatment plans and discuss realistic outcomes with patients when encountering LMPR injuries.

LEVEL OF EVIDENCE

IV.

Patients with meniscus posterolateral root tears repair during ACL reconstruction achieve comparable post-operative outcome than patients with isolated ACL reconstruction

PURPOSE

Lateral posterior meniscal root tear (LPMRT) repair, at the time of anterior cruciate ligament (ACL) reconstruction are increasingly being performed. The aim of this study was to compare the clinical and functional outcomes, as well as the complication rates at a minimum of 2 years follow-up, between an isolated ACL reconstruction group with intact menisci and a combined ACL reconstruction and LPMRT repair group.

METHODS

All patients who underwent combined ACL reconstruction and LPMRT repair between 2016 and 2020 were included in the study. They were matched with an isolated ACL reconstruction group with intact menisci based on age, gender and the pre-injury IKDC score. The KOOS, ACLRSI Tegner-Lysholm score and the TELOS-test were collected pre- and postoperatively; complications (re-rupture, recurrence or persistence of a high grade pivot shift, new meniscal injury) were recorded. All LPMRTs were repaired using transtibial pull-out technique.

RESULTS

After matching, 100 patients were included in this study (mean age 29.6 ± 1.0 years and mean follow-up 42.9 ± 7.3 months): 50 patients in the isolated ACL reconstruction group with intact menisci (group A) and 50 in the combined ACL reconstruction and LPMRT repair group (group B). Preoperatively, patients in group B had significant lower KOOS scores (Global 55.9 ± 2.9 vs. 64.6 ± 2.3, p = 0.02), but similar ACLRSI, TEGNER and TELOS scores. At the last follow-up, all functional scores had improved, and no significant difference between the two groups on any score was observed. There was also no difference in terms of complications rates.

CONCLUSION

At a minimum of 2 years follow-up (mean follow-up 42.9 months), LPMRT repair during ACL reconstruction has no significant difference in terms of post-operative functional outcomes compared to the isolated ACL reconstruction group.

LEVEL OF EVIDENCE

Level III.

Concomitant Medial and Lateral Meniscus Posterior Horn Root Repair With ACL Reconstruction Using Trans-Tibial Tunnel Technique

Concomitant medial meniscus posterior horn root tears and lateral meniscus posterior horn root tears are rare in occurrence. There is limited literature on the simultaneous repair of medial and lateral meniscus root tears, with ACL reconstruction. We discuss management of concomitant medial meniscus posterior horn root tear (MMPHRT), lateral meniscus posterior horn root tear (LMPHRT), and anterior cruciate ligament (ACL) tear. We highlight the surgical technique in which we perform a repair of both medial and lateral meniscus posterior horn root repairs with ACL reconstruction. We explain the sequence of such a repair to avoid tunnel coalescence.

Transtibial Pullout Repair of Lateral Meniscus Posterior Root Tear with Tissue Loss: A Case with Anterior Cruciate Ligament Injury and Medial Meniscus Tear

Lateral meniscus (LM) posterior root tear (LMPRT) is mainly caused by trauma, especially trauma associated with anterior cruciate ligament (ACL) injuries. Although a transtibial pullout repair or a side-to-side repair is commonly performed for LMPRT, to the best of our knowledge, there is no clinical report of LMPRT with tissue loss using the pullout technique. Thus, the purpose of this report was to describe a clinical, radiographic, and arthroscopic outcome after pullout repair for a case of LMPRT with a large defect with a chronic ACL tear and complex medial meniscus (MM) tears. A 31-year-old man complained of knee pain and restricted range of motion after twisting his knee when he stepped on an iron pipe. The patient had a football-related injury to his right knee 14 years before presentation, and since then, the patient's knee has given out more than 10 times but was left unassessed. Magnetic resonance imaging showed LMPRT with tissue loss, ACL tears, and complex MM tears. Transtibial pullout repair of the LMPRT with ACL reconstruction and MM repairs were performed. Following the pullout repair of the LMPRT, an approximately 6 mm gap remained between the LM posterior root and root insertion. However, magnetic resonance imaging and second-look arthroscopy at 1 year postoperatively revealed meniscal healing, gap filling with some regeneration tissue, of the LM posterior root. Furthermore, the lateral meniscus extrusion in the coronal plane improved from 3.1 mm (preoperative) to 1.6 mm (1 year postoperatively). Transtibial pullout repair with the remaining gap could be a viable treatment option for LMPRT with tissue loss, combined with ACL reconstruction.