Posterior Horn Lateral Meniscal Oblique Radial Tear in Acute Anterior Cruciate Ligament Reconstruction Incidence and Outcomes After All-Inside Repair: Clinical and Second-Look Arthroscopic Evaluation

Management of Meniscus Pathology with Concomitant Anterior Cruciate Ligament Injury

PURPOSE OF REVIEW

The purpose of this review is to summarize current clinical knowledge on the prevalence and types of meniscus pathology seen with concomitant anterior cruciate ligament (ACL) injury, as well as surgical techniques, clinical outcomes, and rehabilitation following operative management of these pathologies.

RECENT FINDINGS

Meniscus pathology with concomitant ACL injury is relatively common, with reports of meniscus pathology identified in 21-64% of operative ACL injuries. These concomitant injuries have been associated with increased age and body mass index. Lateral meniscus pathology is more common in acute ACL injury, while medial meniscus pathology is more typical in chronic ACL deficiency. Meniscus tear patterns associated with concomitant ACL injury include meniscus root tears, lateral meniscus oblique radial tears of the posterior horn (14%), and ramp lesions of the medial meniscus (8-24%). These meniscal pathologies with concomitant ACL injury are associated with increased rotational laxity and meniscal extrusion. There is a paucity of comparative studies to determine the optimal meniscus repair technique, as well as rehabilitation protocol, depending on specific tear pattern, location, and ACL reconstruction technique. There has been a substantial increase in recent publications demonstrating the importance of meniscus repair at the time of ACL repair or reconstruction to restore knee biomechanics and reduce the risk of progressive osteoarthritic degeneration. Through these studies, there has been a growing understanding of the meniscus tear patterns commonly identified or nearly missed during ACL reconstruction. Surgical management of meniscal pathology with concomitant ACL injury implements the same principles as utilized in the setting of isolated meniscus repair alone: anatomic reduction, biologic preparation and augmentation, and circumferential compression. Advances in repair techniques have demonstrated promising clinical outcomes, and the ability to restore and preserve the meniscus in pathologies previously deemed irreparable. Further research to determine the optimal surgical technique for specific tear patterns, as well as rehabilitation protocols for meniscus pathology with concomitant ACL injury, is warranted.

Meniscal Radial Tears Repaired with All-Inside and Inside-Out Techniques Result in Improved Clinical Outcome Scores; However, More Complications are Reported After Inside-Out Repair: A Systematic Review

PURPOSE

To compare patient-reported outcomes (PROs), failure, and healing rates following all-inside (AI) repair versus inside-out (IO) repair for the treatment of meniscal radial tears.

METHODS

A literature search was performed according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using the Scopus, PubMed, and Embase computerized databases. Level of evidence I through IV human clinical studies evaluating PROs and/or the incidence of failure and healing following AI versus IO repairs for meniscal radial tears were included. Clinical failure was defined by the presence of joint-line tenderness, a positive McMurray test, and mechanical symptoms such as locking, catching, or giving way. Study quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) criteria and Modified Coleman Methodology Score (MCMS).

RESULTS

Ten studies published from 2008 to 2023 comprising 205 patients were identified including 142 patients who underwent AI repair and 63 patients who underwent IO repair for radial meniscus tears. Postoperative Lysholm and Tegner scores ranged from 90.8 to 95.6 and 5.7 to 8.2, respectively, in the AI repair group, compared to 86.9 to 94.2 and 6 to 7.5, respectively, in the IO repair group, and all patients exceeded published values for MCID for the Lysholm score. Clinical failure ranged from 0% to 40% in the AI group and 0% to 62.5% in the IO group. Healing assessments on second-look arthroscopy revealed failure rates ranging from 0% to 13.3% in the AI group and 0% to 39% in the IO group. Complete and partial healing ranged from 28.6% to 92.3% in the AI group and from 25% to 70% in the IO group. Chondral damage on second-look arthroscopy ranged from 0% to 95% in the IO group and 0% to 57.7% in the AI group. Postoperative complications ranged from 0%-2% within the AI group, while no complications were reported in the IO group. No implant-related complications were reported in any study group.

CONCLUSION

Both all-inside and inside-out repairs for meniscal radial tears demonstrated improved PROs; however, current literature suggests that the IO technique may have higher failure rates both clinically and on second-look arthroscopy.

Outcomes of Lateral Meniscal Oblique Radial Tear Repair Compared With Intact Meniscus After ACL Reconstruction: A Cohort Study

Background

Recently, the posterior horn lateral meniscal oblique radial tear (LMORT) was identified in 12% of acute anterior cruciate ligament (ACL) injuries. However, patient-reported outcomes for repair of this relatively common tear have not been reported.

Purpose

To determine the minimum 2-year functional outcomes after LMORT repair at the time of ACL reconstruction (ACLR) compared to a matched cohort of patients who underwent isolated ACLR (iACLR).

Study Design

Cohort study; Level of evidence, 3.

Methods

Included were 100 patients (mean age at surgery, 21 years; range, 13-45 years) who underwent primary ACLR between 2010 and 2018. The mean follow-up period was 4.1 ± 2.0 years (range, 2.0-9.2 years). A total of 50 patients with surgically repaired LMORT type 3 or type 4 lesions, defined as partial or complete tears >10 mm from the root (LMORT group) were matched 1:1 based on age, date of surgery, and graft choice with 50 patients who underwent iACLR (iACLR group). The postoperative outcomes were compared between groups using the International Knee Documentation Committee subjective score (sIKDC) and the Tegner activity scale. An updated medical history was obtained via the electronic medical record to determine any subsequent complications and reoperations.

Results

There was 1 ACL graft failure in each group as well as 5 (10%) reoperations per group. None of the patients in the LMORT group necessitated a lateral meniscal revision repair or partial meniscectomy. The LMORT and iACLR groups reported comparable sIKDC scores (92.5 ± 6.8 vs 91.9 ± 8.2, respectively; P = .712) as well as Tegner scores (6.7 ± 1.8 vs 6.6 ± 1.8, respectively; P = .910) at final follow-up. No failures of the LMORT repairs were reported.

Conclusion

The study findings demonstrated that reoperations, graft failure rates, patient-reported outcomes, and patient activity levels at ≥2 years after type 3 and 4 LMORT repairs at the time of ACLR compared favorably with those of a matched cohort of patients who underwent iACLR with intact meniscus.