Abstract
Background:
Meniscal tears occur at the time of anterior cruciate ligament (ACL) injury in 55% to 65% of patients. These tears exhibit different healing patterns and behavior compared with meniscal tears in a stable knee. The optimal management of different medial, lateral and bicompartmental tears during primary ACL reconstruction (ACLR) has yet to be defined.
Purpose:
To evaluate the reoperation rates associated with different meniscal treatment strategies and analyze the effect of medial, lateral, and bicompartmental meniscal tears on ACLR outcomes.
Study Design:
Cohort study; Level of evidence, 2.
Methods:
This investigation included 1137 patients undergoing primary ACLR with a concomitant meniscal injury. Patients with chondral defects and multiligament knee injuries were excluded. Meniscal treatments were divided into 3 categories: left in situ (LIS), partial meniscectomy (PM), and repair. Reoperation was defined as the primary endpoint, and multivariable analysis was conducted to identify patient and tear characteristics associated with reoperation. The influence of different treatment strategies on return to play (RTP), ACL reinjury rate, and patient-reported outcome measures (PROMs) was reported at 2 years. The PROMs recorded were the International Knee Documentation Committee (IKDC) score, the Marx Activity Rating Scale, and the Anterior Cruciate Ligament–Return to Sport after Injury score.
Results:
The mean age was 24.0 ± 6.9 years, and 76% of patients were male. Most injuries were noncontact (64.9%), commonly resulting from pivoting/sidestepping (50.1%). No significant differences in injury mechanism, playing surface, or footwear type were found between medial, lateral, or bicompartmental tears. Reoperation rates for patients were low for lateral (1.3%), medial (2.6%), and bicompartmental tears (3.2%) LIS at the time of ACLR. The rate of reoperation/subsequent meniscectomy for medial meniscal repairs (14.8%) was significantly higher than for other medial treatments (hazard ratio 12.8; P < .001). Patients who underwent meniscal repair with a concomitant tear in the opposite compartment (repair + PM/LIS) had the highest reoperation rates (16.7%) and lowest RTP rates (60%). IKDC scores were significantly lower for patients who underwent lateral meniscal repair (81.1 ± 15.3) compared with other types of lateral meniscal management (P < .027). ACL reinjury rate was not influenced by meniscal treatment. A higher preoperative Marx score increased the risk of reoperation in all groups.
Conclusion:
Stable meniscal tears LIS during ACLR had low reoperation rates and good patient-reported outcomes, including patients with bicompartmental tears. Medial meniscal repairs had the highest risk of reoperation, particularly when another tear was present in the lateral compartment. Lateral meniscal repairs were associated with lower IKDC scores compared with other lateral meniscal treatment strategies.
Keywords
The anterior cruciate ligament (ACL) and the menisci are essential structures for maintaining knee stability, particularly for athletes participating in high-demand, pivoting sports. 2 Meniscal injuries frequently accompany ACL injuries, with reported prevalence rates ranging from 55% to 65%.14,23,33 When these injuries occur together, knee joint mechanics are significantly altered, and several studies have suggested that this accelerates the development of osteoarthritis.18,24,34 Accordingly, ACL reconstruction (ACLR) is generally recommended for patients with ACL injury in order to restore joint stability and function.35,36 The current approach to managing meniscal injuries is to preserve as much meniscus tissue as possible.16,30
Several management options are available for acute meniscal tears identified during ACLR, including meniscal repair, partial meniscectomy (PM), and leaving tears in situ. The decision regarding which treatment to use depends on the tear location, length, chronicity, and pattern.8,32,38 A systematic review of meniscal tears left in situ (LIS) reported reoperation rates of 4% to 22% for lateral meniscal tears and 10% to 66% for medial meniscal tears, underscoring the importance of patient selection. 28 Recent evidence suggests that the most appropriate tears to leave in situ are peripheral, longitudinal lateral meniscal tears.7,32 In contrast, the less predictable nature of medial meniscal tears LIS has been highlighted.7,32 PM has been shown to exhibit favorable patient-reported outcomes for patients undergoing ACLR, although concerns exist regarding the association of this modality with osteoarthritis in the longer term.9,27 Regarding meniscal repair, the biological environment created during ACL tunnel drilling and hematoma formation is hypothesized to promote meniscal healing. 12 However, the failure rate of meniscal repair during ACLR is still high, approximately 14% to 21% at 5 years, and likely depends considerably on factors such as activity level, patient age, drilling method during ACLR, and meniscal repair technique.5,22,40 Notably, most existing evidence comes from multicenter or registry data, which has contributed to variability in reported outcomes. Furthermore, the influence of bicompartmental meniscal injuries on outcomes remains underexplored, despite recent studies indicating that these injuries occur in 26% of patients with ACL injuries and have the potential to alter knee biomechanics.7,11,26
Therefore, the primary aim of this study was to determine the reoperation rates for medial, lateral, and bicompartmental meniscal tears managed by repair, PM, or LIS during ACLR. Secondary objectives included evaluating return-to-play (RTP) rates, ACL reinjury rates, and patient-reported outcomes in patients with combined ACL-meniscal injuries. Finally, we aimed to identify patient and tear-related characteristics associated with reoperation.
Methods
Patient Cohort
This study analyzed a consecutive cohort of patients undergoing primary ACLR with concomitant meniscal tears between January 2014 and December 2018. Data were collected prospectively by 2 orthopaedic knee surgeons (R.M., M.J.) at our institution and analyzed retrospectively. Patients were included if they were aged between 13 and 49 years and underwent primary ACLR, regardless of their level of sports participation. Exclusion criteria included previous meniscectomy, degenerative meniscal pathology, chondral injury, revision ACLR, multiligament knee surgery, and being outside the age range. Meniscal lesions were excluded if they consisted solely of meniscocapsular separation, with no extension into the meniscal substance. These were regarded as peripheral detachments at the meniscocapsular junction rather than intrinsic meniscal tears, in line with the European Society of Sports Traumatology, Knee Surgery & Arthroscopy (ESSKA) 2019 meniscus consensus. 16 Preoperative data collection included a standardized questionnaire documenting demographic details, injury characteristics, sports participation, and the Marx Activity Rating Score. 19 All participants provided informed consent before their involvement in this research, and our institution granted ethical approval to undertake this study.
Surgical Technique: ACL and Meniscus
The surgical procedures were performed at our hospital by 2 knee surgeons using consistent arthroscopic techniques with either bone–patellar tendon–bone (BPTB), quadriceps tendon (QT), or hamstring tendon (HT) autografts. Graft selection was tailored to each patient based on their consultation with each surgeon. BPTB autografts were generally preferred, particularly for patients involved in high-demand sports. HT and QT autografts were chosen for patients with open physes or a history of patellofemoral issues, such as tendinopathy, Osgood-Schlatter disease, patella baja, or bipartite patella or for those concerned about potential kneeling discomfort. BPTB grafts were secured using metal interference screws (Softsilk; Smith & Nephew), whereas HT grafts were fixed with an EndoButton (CL Ultra; Smith & Nephew) for femoral fixation and a nonbioabsorbable screw (Biosure PK; Smith & Nephew) for tibial fixation. Tunnel positions were placed at the anatomic footprints of the original ACL, and femoral drilling was performed through an anteromedial portal. Meniscal tears were evaluated and classified arthroscopically. Tears were divided by compartment (medial, lateral, bicompartmental) and further subdivided by how they were managed (LIS, PM, or repair). Patients with bicompartmental tears who underwent repair + LIS (n = 18) or repair + PM (n = 12) were combined into a single group to enable meaningful analysis, as the sample size was limited. The patterns of tears included in this study were longitudinal-vertical, bucket-handle, radial, undersurface, vertical flap, horizontal, meniscus root, and complex tears. Meniscal tears were managed based on tear stability, location, chronicity, and pattern. Meniscal stability was assessed using a probe and considered stable if the torn segment could not be displaced into the joint to cause catching or locking symptoms. Unstable longitudinal-vertical, bucket-handle, and radial tears were typically managed with repair. Stable longitudinal-vertical tears and undersurface tears were LIS. Vertical flap, root tears, and complex tears, as well as nonreducible bucket-handle tears, generally required PM. For tears managed with PM, the damaged area was trimmed to a stable edge while preserving as much meniscus tissue as possible. Meniscal repairs were conducted using an all-inside suture device (Fast-Fix; Smith & Nephew).
Rehabilitation
Postoperatively, patients were permitted to bear weight as tolerated without a brace, except in cases of unstable radial tear repair, where a nonweightbearing protocol was applied. Crutches were generally used for the first 2 weeks. Follow-up evaluations with the surgeons were scheduled at 2 weeks, 3 months, 6 months, and 9 months after surgery. Given the geographical distribution of participants, most completed their rehabilitation with local clinicians. Throughout rehabilitation, patients underwent several physical tests to monitor progress, following testing protocols described in previous studies. 15 During these follow-up assessments, the orthopaedic surgeon set minimum criteria for participants to focus on before returning to sport. These included the absence of joint effusion, restoration of quadriceps strength with effective control during single-leg squats, and normal patterns in running and limb symmetry index of at least 90%. These criteria were not evaluated as part of a formal RTP protocol.
Patient Outcomes
Reoperation for meniscal pathology was defined as any subsequent meniscal repair or meniscectomy within the same compartment as the meniscal tear managed at the time of the index ACLR. For patients with bicompartmental tears, reoperation was defined as a repeat meniscal procedure in either compartment. ACL reinjury was recorded for both the ipsilateral and contralateral knee. These patients were identified during the follow-up period or if they returned to the clinic before the scheduled follow-up time with a confirmed diagnosis of a second ACL injury on magnetic resonance imaging or arthroscopy. This study defined “return to play” as the unrestricted resumption of a patient's preinjury sport consistent with the 2016 consensus statement on return to sport. 3 Patients recorded this on a questionnaire, including the date they returned. Patient-reported outcome measures (PROMs) were collected at 2-year follow-up via email or phone correspondence. The PROMs recorded were the International Knee Documentation Committee (IKDC) score, 13 Marx Activity Rating Scale, 19 and the Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) score. 39 Those who experienced ACL reinjury or underwent meniscal reoperation were excluded from the analysis of PROMs at the final follow-up.
Statistical Analysis
Continuous variables are displayed as mean ± standard deviation or median (interquartile range), whereas categorical variables are displayed as numbers and percentages. We compared the proportions of binary outcome measures (reoperation rate, RTP, ACL reinjury) using the χ2 test and compared the distribution of ≥3 continuous variables (PROMs) using the Kruskal-Wallis test. Cox proportional hazard models were used to evaluate differences in reoperation rate based on patient and tear-related factors. For each patient, the study commenced on the date of surgery. For patients who experienced repair failure, their event time was defined by the date of subsequent surgery, whereas patients without failure were censored at 2-year follow-up. The model adjusted for clinically relevant confounders, including age, sex, graft type, preoperative Marx score, and time from injury to surgery. The threshold for statistical significance was set at P < .05. Data analysis and graphical presentation were performed using STATA Version 18.0 (StataCorp LP).
Results
A total of 1955 patients had a combined ACL and meniscal injury between 2014 and 2018. Of these, 1137 patients underwent primary ACLR and were managed for an isolated, nondegenerative meniscal tear (Figure 1). No follow-up data were available for 110 patients, giving an overall follow-up rate of 90.3% at 2 years. The mean age was 24.0 ± 6.9 years (males, 76%; females, 24%) (Table 1). Preoperatively, 95% of participants anticipated returning to a similar or higher level of sport after surgery. The primary mechanisms of injury were predominantly noncontact (64.9%), with pivoting/sidestepping (50.1%) and jumping/landing (19.6%) being the most common actions leading to injury. Most participants were involved in pivoting field sports: Gaelic football (43.6%; n = 496), hurling (18.4%; n = 209), soccer (16.0%; n = 182), and rugby (8.7%; n = 100). No significant difference was found in the mechanism of injury for those who had lateral, medial, or bicompartmental meniscal tears (P = .283). Patients predominantly sustained their knee injuries on grass (P = .299) and wore molded studs at the time of injury (Table 1). No difference was found in the type of footwear used when medial, lateral, or bicompartmental meniscal injuries were sustained (P = .231). The median time from injury to ACLR was 2.8 ± 2.0 months, comparable between all treatment groups (Table 1; Figure 2).
Flowchart of patient inclusion in the analysis. ACLR, anterior cruciate ligament reconstruction; LIS, left in situ; PM, partial meniscectomy.
Baseline Patient Demographic Characteristics and Preoperative Data for Patients With Combined Anterior Cruciate Ligament–Meniscal Injuries a
Values are expressed as n (%) or mean ± SD.
Boxplot of the time from knee injury to anterior cruciate ligament reconstruction. The median time from injury to surgery was 2.8 ± 2.0 months. LIS, left in situ; PM, partial meniscectomy.
The most common graft types used were BPTB grafts (85.8%), followed by HT grafts (13.5%) (Tables 2 and Table 3). The most common types of medial meniscal tears were partial, undersurface tears (n = 158; 49.2%) and longitudinal tears (n = 105; 32.7%). Tears were most common in the posterior horn of the medial meniscus (89.1%). Concerning the treatment of unilateral medial meniscal tears, 210 (65.4%) were LIS, 53 (16.5%) were managed with PM, and 58 (18.1%) were repaired.
Unicompartmental Tears at the Time of Anterior Cruciate Ligament Reconstruction: Location, Pattern, and Treatment Characteristics a
Values are expressed as n (%).
Bicompartmental Meniscal Tears at the Time of Anterior Cruciate Ligament Reconstruction: Location, Pattern, and Treatment Characteristics a
Values are expressed as n (%).
Lateral meniscal tears were most common in the posterior horn (62.5%) and the midbody (30.3%). The most common tear patterns were longitudinal (n = 201; 35%), radial (n = 109; 19%), and vertical flap (n = 90; 15.7%) (Table 2).
There were 242 patients with bicompartmental meniscal tears. The most common combinations of tears were; bicompartmental longitudinal tears (n = 48; 19.8%), an undersurface medial meniscal tear with a longitudinal tear of the lateral meniscus (n = 26; 10.7%), and a longitudinal tear of the medial meniscus and radial tear of the lateral meniscus (n = 21; 8.7%) (Table 3). PM was performed more frequently for lateral tears (36.4%) compared with medial (13.2%), whereas repair was undertaken in 15.7% of medial and 4.1% of lateral tears (Table 3).
Medial Meniscus
No difference was found in the overall reoperation rate between medial, lateral, and bicompartmental meniscal tears (4.1%, 1.8%, and 4.1%, respectively; P = .085). Patients who underwent medial meniscal repair had a significantly higher rate of meniscal reoperation (14.8%) compared with those who had a meniscal tear LIS (2.6%) or underwent PM (0%) (P < .001) (Table 4). All patients with medial meniscal tears undergoing ACLR demonstrated high RTP rates: 86.5% for tears LIS, 81.3% after PM, and 87% after repair. The mean time to RTP was 10.7 ± 3.9 months for the LIS group, which was comparable across all groups (P = .859). Ipsilateral and contralateral ACL reinjury rates did not differ significantly between the treatment groups at 2 years of follow-up. No statistically significant difference was found in PROMs between different medial meniscal treatment groups (Table 4; Figure 3).
Outcomes for Isolated Medial Meniscal Tears Managed During ACLR at 2 Years of Follow-up a
Values are expressed as n (%) or mean ± SD. Boldface indicates statistical significance. ACL, anterior cruciate ligament; ACLR, anterior cruciate ligament reconstruction; ACL-RSI, ACL–Return to Sport After Injury; IKDC, International Knee Documentation Committee; LIS, left in situ; PM, partial meniscectomy; RTP, return to play.
Mean International Knee Documentation Committee (IKDC) score over time by treatment type for isolated lateral vs meniscal tears. LIS, left in situ; PM, partial meniscectomy.
Among the repaired medial meniscal tears, 44 were longitudinal tears, 6 were bucket-handle tears, and 4 were complex tears. Notably, all 8 of the 54 repair failures occurred in longitudinal tears in the posterior horn. Multivariable analysis revealed that reoperation for a medial meniscal tear was associated with meniscal repair (hazard ratio [HR], 12.8; 95% CI, 5.0-32.5; P < .001) and a higher preoperative Marx score (HR, 1.13; 95% CI, 1.01-1.27; P < .024).
Lateral Meniscus
Patients with lateral meniscal injuries at the time of ACLR reported good outcomes. Reoperation rates were higher in the Repair group (7.4%) compared with the PM and LIS groups, although this was not statistically significant (P = .069). RTP rates were significantly lower in the LIS group (79.9%) compared with the PM group (89.3%) and the Repair group (88.9%) (P = .018). The time from surgery to RTP was similar across groups (P = .650). The treatment of lateral meniscal tears did not influence the rates of ipsilateral or contralateral ACL reinjury (Table 5). The IKDC scores were significantly lower in the lateral meniscal Repair group (81.1 ± 15.3) compared with the PM and LIS groups (P = .027). Among the 27 repairs of the lateral meniscus, failure (2/27) occurred in a complex tear and a longitudinal tear of the posterior horn. Multivariable analysis revealed that lateral meniscal reoperation was associated with higher preoperative Marx scores (HR, 1.1; 95% CI, 1.01-1.23; P < .049).
Outcomes for Isolated Lateral Meniscal Tears Managed During ACLR at 2 Years of Follow-up a
Values are expressed as n (%) or mean ± SD. Boldface indicates statistical significance. ACL, anterior cruciate ligament; ACLR, anterior cruciate ligament reconstruction; ACL-RSI, ACL–Return to Sport After Injury; IKDC, International Knee Documentation Committee; LIS, left in situ; PM, partial meniscectomy; RTP, return to play.
Bicompartmental Meniscal Tears
In patients with bicompartmental meniscal tears undergoing ACLR, the highest reoperation rates were seen in the Repair + PM/LIS group (16.7%). In this group, nearly all patients (29/30) underwent a medial meniscal repair with an associated lateral meniscal tear. All 5 patients who underwent reoperation in this group did so for failure of a repaired longitudinal tear of the posterior horn of the medial meniscus with an all-inside, vertical mattress repair. The RTP rate was lowest in the Repair + PM/LIS group (60%) and highest in the LIS + LIS group (87.1%) (Table 6). The mean time from surgery to RTP ranged from 11.0 to 13.1 months, which was not statistically significantly different between treatment groups (P = .553). The rate of ipsilateral ACL reinjury was 20% (1/5 patients) in the Repair + Repair group and as low as 0% in the LIS + PM and the PM + PM groups (P < .039). The rate of contralateral ACL reinjury was not significantly different between treatment groups (P = .783). The IKDC scores were significantly higher in the Repair + Repair group (90.6 ± 7.1) compared with other groups, with the lowest IKDC scores in the Repair + PM/LIS group (81.3 ± 11.1; P = .014). No significant differences between treatment groups were observed in the Marx Activity Scale scores (P = .082) or ACL-RSI scores (P = .324) (Table 6; Figure 4).
Outcomes for Bicompartmental Meniscal Tears Managed During ACLR at 2 Years of Follow-up a
Values are expressed as n (%) or mean ± SD. Boldface indicates statistical significance. ACL, anterior cruciate ligament; ACLR, anterior cruciate ligament reconstruction; ACL-RSI, ACL–Return to Sport After Injury; IKDC, International Knee Documentation Committee; LIS, left in situ; PM, partial meniscectomy; RTP, return to play.
Mean International Knee Documentation Committee (IKDC) score over time by treatment type for bicompartmental meniscal tears. Only 5 observations were made in the Repair + Repair group, so they were not included in this graph. LIS, left in situ; PM, partial meniscectomy.
The reoperation rate was significantly higher for bicompartmental tears when HT autograft was used compared with BPTB graft (12.5% vs 3.1%, respectively; P < .030). Multivariable analysis revealed that graft type (HR, 8.5; 95% CI, 2.3-31.2; P < .001) and a higher preoperative Marx score (HR, 1.39; 95% CI, 1.02-1.9; P < .001) were associated with reoperation for bicompartmental meniscal tears.
Discussion
The main finding of this study was that reoperation rates were low for patients with lateral (1.3%), medial (2.6%), and bicompartmental tears (3.2%) that were LIS at the time of ACLR, suggesting this is an effective management option for select tears. We also determined that longitudinal tears of the medial meniscus treated with all-inside repair had a high failure rate (14.8%). Lateral meniscal repairs were associated with lower IKDC scores (81.1 ± 15.3 points) compared with other treatments for lateral meniscal tears. This finding highlights the potential morbidity associated with meniscal repair. Ipsilateral or contralateral ACL reinjury rates were not associated with medial or lateral meniscal treatment. Bicompartmental meniscal injuries influenced outcomes, with the Repair + PM/LIS group demonstrating inferior outcomes, emphasizing the significance of these injuries.
Our study found that both lateral and medial meniscal tears LIS during ACLR had a low reoperation rate and good patient-reported outcomes. Similarly, Shelbourne et al 32 demonstrated a reoperation rate of 2.4% in 332 patients with lateral meniscal tears LIS, with 96% of patients achieving normal or nearly normal knee function scores at 5 years of follow-up. Another study by Fitzgibbons and Shelbourne 8 evaluated 189 lateral meniscal tears LIS at a mean of 2.6 years postoperatively. The main tear patterns assessed were “posterior horn avulsions” (n = 52), “complete/partial longitudinal tears posterior to the popliteus tendon” (n = 99), and “stable longitudinal tears beginning in the posterior horn and extending anterior to the popliteus tendon” (n = 27). All patients in this study returned to sport with asymptomatic meniscal tears. 8 Our findings also align with the outcomes reported by the MOON Group at 6 years, which found that only 2.2% (3/137) of lateral meniscal tears and 5.6% (4/71) of medial meniscal tears LIS required reoperation. 7 Interestingly, several studies have reported higher rates of meniscal failure for medial tears LIS, although this was not the case in our study. Talley et al 37 found that 21% of stable longitudinal medial meniscal tears propagated into bucket-handle tears requiring reoperation. Shelbourne et al 31 evaluated 419 peripheral longitudinal medial meniscal tears managed with trephination alone and found a failure rate of 16.3%. However, the authors concluded that nonoperative management was appropriate given that these failure rates are equivalent to the rates associated with meniscal repair but this strategy avoided the risks of adjunctive surgical procedures. 25 These previous studies provided much of the foundation for the 2019 ESSKA consensus on acute traumatic meniscal tears, which recommended that stable lateral meniscal tears may be safely LIS whereas medial tears are generally advised to be repaired (grade D evidence = expert opinion level). However, based on our results, we believe that leaving lateral and medial meniscal tears in situ is associated with a low reoperation rate and allows return to sport with good patient-reported outcomes. Our study is also the first to report on a large cohort of bicompartmental meniscal tears LIS and supports leaving these tears in situ at the time of ACLR.
Our results demonstrated that reoperation rates were highest for patients who underwent medial meniscal repair. Furthermore, all 5 meniscal failures in the bicompartmental tear group (Repair + PM/LIS) involved a medial meniscal repair. The high reoperation rate associated with medial meniscal repair identified in our study has been observed in other studies.5,22,29 In a systematic review, Nepple et al 22 reported reoperation rates of 21.2% for meniscal repairs associated with ACLR at a minimum of 5 years follow-up. They also noted that the rate of medial meniscal repair failure was higher (23.9%) compared with lateral repair failure (12.6%) and that there was no difference in repair failure rates between those who underwent concomitant ACLR and those with an intact ACL. Similarly, Borque et al 5 found higher failure rates for medial meniscal repairs than lateral meniscal repairs, especially when an all-inside technique was used. In contrast, the MOON cohort reported similar failure rates for medial (13.6%) and lateral (13.9%) meniscal repairs at the time of ACLR at 6 years follow-up. 40 The medial meniscus is more securely attached to its surrounding structures and is less mobile, increasing its susceptibility to injury, especially if residual laxity is present. 25 It also bears greater weightbearing loads and experiences higher meniscofemoral peak pressures than the lateral meniscus. 1 These findings suggest that medial meniscal repairs performed during ACLR may carry inherently higher reoperation risks, emphasizing the need for careful patient selection and individually tailored surgical techniques.
We found that the risk of reoperation was higher for patients with higher preoperative activity levels, measured by the Marx score. The 2019 ESSKA consensus noted that the evidence is inconsistent regarding the influence of activity level on meniscal reoperation because many repairable tears may undergo meniscectomy due to the benefits of quicker recovery and lower reoperation rates. 16 It is also challenging to quantify sporting exposure across different sports and varying measurement methods. Another factor associated with reoperation for patients with bicompartmental meniscal tears in our study was HT autograft use. This is particularly noteworthy as a recent New Zealand ACL registry study found that HT autografts, along with medial chondral damage and younger age, were associated with medial meniscal repair failure. 29 Although not investigated in our study, the association between HT grafts and meniscal repair failure may be due to the higher residual joint laxity observed with HT autografts compared with BPTB grafts.4,21,29 Future studies should investigate in more detail whether laxity or graft type is related to meniscal failure, given the role of the menisci as secondary stabilizers to anterior translation and rotation.10,17
Our study demonstrated lower IKDC scores (81.1 points) in the lateral repair group compared with other lateral meniscal treatments and a reoperation rate of 7.4%. Westermann et al 40 reported a median IKDC score of 85.7 points at 2 years, which improved to 88.4 points at 6 years in 62 patients who underwent successful lateral meniscal repair. Other results from the MOON cohort have suggested that medial meniscal repair is associated with reduced IKDC scores and that lateral PM and lateral LIS both improve IKDC scores at 6 years' follow-up. 6 Regarding activity levels measured by the Marx score, the MOON cohort demonstrated findings similar to ours by showing no reduction in activity levels associated with different meniscal treatments. Likely, the number of complex tears and bucket-handle tears in our lateral meniscal repair group contributed to lower IKDC scores compared with other studies. 6
The results of our study show that ipsilateral and contralateral ACL reinjury rates were not strongly influenced by the treatment of isolated medial or lateral meniscal tears. This was true for the bicompartmental meniscal tear group despite the potential biomechanical alterations associated with these injuries. Most large cohort studies on concomitant ACLR and meniscal repair only report meniscus-related outcomes, making comparison of ACL reinjury rates between cohorts difficult.23,38,40 It is likely the rate of ACL revision was low in our cohort because most patients underwent BPTB reconstruction, a robust graft associated with high RTP rates. 20
Strengths and Limitations
This study's strengths include a large sample size and a comprehensive follow-up. Strict exclusion criteria were applied (chondral injuries and degenerative meniscal pathology) to ensure homogeneous comparisons across treatment types. Consistent surgical techniques and a standardized classification of meniscal tears permitted a detailed subgroup analysis of management strategies. This is also the most comprehensive analysis of bicompartmental meniscal tears and the first to thoroughly evaluate the influence of combined meniscal-ACL injuries on both ipsilateral and contralateral ACL reinjury. One of the limitations of this study was the need to combine the Repair + PM and Repair + LIS groups due to low patient numbers in these groups. It is also important to recognize that multiple definitions of ramp lesions exist in the literature. In the present study, ramp lesions were defined as isolated meniscocapsular detachments and excluded from assessment. Furthermore, the exact length of meniscal tears was not documented. In the future, studies with randomized treatment protocols could help refine management recommendations further.
Conclusion
This study assessed the outcomes for various management strategies for meniscal tears identified during ACLR, focusing on reoperation rates, RTP, ACL reinjury rates, and patient-reported outcomes. Our findings indicate that meniscal tears LIS during ACLR had low reoperation rates and good patient-reported outcomes, including bicompartmental tears. This supports a selective nonoperative approach for stable longitudinal and undersurface meniscal tears. Medial meniscal tears had the highest risk of reoperation, particularly when another tear was present in the lateral compartment. Patients who underwent lateral meniscal repair had lower IKDC scores than those who underwent PM or had a tear LIS. Patients with bicompartmental meniscal injuries who underwent Repair + PM/LIS had inferior outcomes, emphasizing the complexity of managing severe bicompartmental meniscal injuries in the setting of ACLR.
Footnotes
Submitted April 24, 2025; accepted November 6, 2025.
The authors have declared that there are no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
