Lateral Meniscus Repair Research Articles

Is the popliteal tendon sufficient for all-inside suture in lateral meniscus repair? A 22-case cadaver study

IntroductionArthroscopic lateral meniscus repair is performed in the “figure-of-4 position” (supine, with the affected knee flexed and the lower leg crossed over the extended contralateral leg), and anchorage is often on the popliteal tendon. Extending the limb at the end of the procedure alters the relations between the popliteal tendon and the repaired meniscus. The present study aimed to assess lateral meniscal suture fixation on the popliteal tendon after a cycle of flexion-extension. HypothesisExtending the knee can induce suture release. Type of studyCadaver study. Materials and methodsTwenty-two fresh adult human cadaver knee specimens were used. Under arthroscopy with all-inside implants, a vertical suture onto the popliteal tendon was performed through the lateral meniscus. Suture status was assessed under arthroscopy after a cycle of flexion-extension, and deemed defective if the suture was sufficiently loose for the arthroscope to be able to be passed through the popliteal hiatus, if the stitch had passed through the meniscus, or if the suture was broken. ResultsThirteen sutures (59.1%) remained well fixed, and 9 (40.1%) were defective: 4 (18.2%) were loose, in 4 (18.2%) the stitch had passed through the meniscus, and in 1 (4.5%) the suture had broken. ConclusionIn a population of elderly cadaver knee specimens, arthroscopic suture of the lateral meniscus to the popliteal tendon was defective after flexion-extension in 40% of cases. Stress seems to be exerted on the suture when extension is resumed. Thus, a single stitch seems insufficient for stable lateral meniscus repair. Clinical implicationsSuture of the lateral meniscus to the popliteal tendon undergoes stress when extension is resumed, potentially causing failure of lateral meniscus repair. Level of evidenceIV.

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

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. 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. 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 ± 10months, 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%). 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 2years. IV.

Analysis of Health-Related Quality of Life and Clinical Evaluations in Patients with the Triad of Combined Knee Injuries.

Combined knee injuries of the anterior cruciate ligament (ACL), medial collateral ligament (MCL), and medial meniscus were called "the unhappy triad" in the past. With recent advances in diagnostic technology, combined ACL, MCL, and lateral meniscus injuries are now known to be the predominant triad. We examined and verified the treatment outcomes of the triad of combined knee injuries from both patient-based subjective evaluation and objective assessments. We studied 49 knees (49 patients) with combined injuries of the ACL, MCL, and lateral meniscus. These cases were divided into those who underwent simultaneous ACL and MCL reconstruction (group A, 18 cases) and those who underwent ACL reconstruction only because MCL injury could be treated conservatively (group B, 31 cases). Clinical evaluation was conducted preoperative and 24 months or longer after surgery. The methods included patient-reported outcomes using Short Form-36, and conventional assessments using Lysholm's score, visual analogue scale (VAS), and quantitative measurement of knee instability using Telos SE. Compared with presurgical scores, the postsurgical Short Form-36 scores showed improvements in all eight subscales, all reaching the national standard values. Significant improvements were observed in the five subscales in group A and seven subscales in group B. Furthermore, significant improvements in Lysholm's score, VAS pain score, and quantitative knee instability were achieved in both groups. This study demonstrated successful clinical outcomes in patients with a triad of knee injuries who were treated with lateral meniscus repair or partial meniscectomy and either combined MCL/ACL reconstruction or ACL reconstruction alone.

Poster 239: Limb Malalignment Fails to Influence Clinical Outcomes of Meniscal Repair

Objectives:Lower limb malalignment causes differences in tibiofemoral contact pressures and may influence outcomes following meniscal repair. Our objective was to evaluate clinical outcomes of meniscal repair in malaligned knees to determine if limb malalignment portends an inferior outcome. We hypothesized that medial meniscus repairs performed in varus knees and lateral meniscus repairs performed in valgus knees would result in poorer patient-reported outcomes when compared to a neutrally aligned knee.Methods:Patients who underwent meniscal repair at a single institution between 2006 and 2018 were identified by retrospective chart review. Patients between the ages of 18 and 65 with full-length weight bearing lower limb radiographs were included. Patients with varus alignment (> 3 degrees) and a medial meniscus repair, or valgus alignment (>3 degrees) and a lateral meniscus repair were considered “at-risk”. Outcomes were assessed through identification of additional surgery on the index meniscus and patient-reported outcome measures (PROMs): Knee Injury and Osteoarthritis Outcome Score (KOOS), Marx activity score, and International Knee Documentation Committee subjective score (IKDC). Failure rates and PROMs were compared between the at-risk and not at risk groups.Results:A total of 58 patients were included with a mean follow-up of 1.6 years. A total of 12 patients were classified as “at-risk”. Repeat surgery on the index meniscus was performed in 1 of 12 “at risk” patients (8.3%) and 7 of 46 (15.2%) in the “not at risk” group (p = 1.00). There were no significant differences between the two groups in KOOS subscales: pain (82.8 vs 85.6, p = 0.55), symptoms (78.2 vs 80.8, p = 0.64), ADLs (88.4 vs 92.9, p = 0.27), Sport/Rec Function (63.8 vs 69.2, p = 0.57), or QOL (58.9 vs 62.3, p = 0.69). There was also no difference in IKDC score (66.9 vs 72.5, p = 0.41) or Marx score (4.2 vs 5.0, p = 0.63) between the two groups.Conclusions:Pre-operative knee malalignment does not appear to negatively influence clinical outcomes of meniscal repair when compared to normal knee alignment.Table 1.Patient-Reported Outcome Scores

Is Nonoperative Treatment Appropriate for All Patients With Type 1 Tibial Spine Fractures? A Multicenter Study of the Tibial Spine Research Interest Group.

Background:Type 1 tibial spine fractures are nondisplaced or ≤2 mm–displaced fractures of the tibial eminence and anterior cruciate ligament (ACL) insertion that are traditionally managed nonoperatively with immobilization.Hypothesis:Type 1 fractures do not carry a significant risk of associated injuries and therefore do not require advanced imaging or additional interventions aside from immobilization.Study Design:Case series; Level of evidence, 4.Methods:We reviewed 52 patients who were classified by their treating institution with type 1 tibial spine fractures. Patients aged ≤18 years with pretreatment plain radiographs and ≤ 1 year of follow-up were included. Pretreatment imaging was reviewed by 4 authors to assess classification agreement among the treating institutions. Patients were categorized into 2 groups to ensure that outcomes represented classic type 1 fracture patterns. Any patient with universal agreement among the 4 authors that the fracture did not appear consistent with a type 1 classification were assigned to the type 1+ (T1+) group; all other patients were assigned to the true type 1 (TT1) group. We evaluated the rates of pretreatment imaging, concomitant injuries, and need for operative interventions as well as treatment outcomes overall and for each group independently.Results:A total of 48 patients met inclusion criteria; 40 were in the TT1 group, while 8 were in the T1+ group, indicating less than universal agreement in the classification of these fractures. Overall, 12 (25%) underwent surgical treatment, and 12 (25%) had concomitant injuries. Also, 8 patients required additional surgical management including ACL reconstruction (n = 4), lateral meniscal repair (n = 2), lateral meniscectomy (n = 1), freeing an incarcerated medial meniscus (n = 1), and medial meniscectomy (n = 1).Conclusion:The classification of type 1 fractures can be challenging. Contrary to prior thought, a substantial number of patients with these fractures (>20%) were found to have concomitant injuries. Overall, surgical management was performed in 25% of patients in our cohort.

Performance and Return to Sport After Meniscal Repair in Professional Baseball Players.

Background:Meniscal repair is an effective treatment option for certain meniscal injuries to preserve meniscal function and limit the progression of knee osteoarthritis. Outcomes after meniscal repair in professional baseball players are not well documented.Purposes/Hypothesis:The purposes of this study were to determine performance and return to sport (RTS) in professional baseball players after meniscal repair and compare the results of medial versus lateral meniscal repair. It was hypothesized that there would be a high RTS rate, with no difference in the rate or timing of RTS between players who underwent medial versus lateral meniscal repair.Study Design:Cohort study; Level of evidence, 3.Methods:All professional baseball players who underwent meniscal repair between 2010 and 2017 were identified using the Major League Baseball Health and Injury Tracking System database. Descriptive information and performance data (before and after injury) for each player were recorded. The rate and timing of RTS were then compared between players who underwent medial versus lateral meniscal repair.Results:Included were 31 patients (mean age, 24 ± 3 years). There were 6 players (19%) who had failed repair, underwent subsequent meniscectomy within 2 years of meniscal repair, and were thus excluded from the performance analysis. Of the remaining 31 players, 68% returned to the same or a higher level of play, and 6% of players returned to a lower level of play. Most repair procedures (60%) were performed using the all-inside technique, and 72% of players underwent lateral meniscal repair. The mean time missed was 187 ± 67 days, and the mean time to RTS at full competitive play was 209 ± 84 days. There were no significant differences in the rate or timing of RTS between players who underwent medial versus lateral meniscal repair (P ≥ .999 and P = .574, respectively). Pitchers saw a decrease in usage but no change in performance after meniscal repair. For batters, most metrics were unchanged, but there was a significant decrease in base stealing and on-base percentage after surgery.Conclusion:The RTS rate after meniscal repair in Major League Baseball players was 74% at a mean of 209 days; 19% of players had failed repair and underwent subsequent meniscectomy within 2 years of repair. No difference in the rate or timing of RTS was observed between players who underwent medial versus lateral meniscal repair.

The Risk of Iatrogenic Peroneal Nerve Injury in Lateral Meniscal Repair and Safe Zone to Minimize the Risk Based on Actual Arthroscopic Position: An MRI Study

Background: Lateral meniscal repair using an all–inside meniscal repair device involves a risk of iatrogenic peroneal nerve injury. To our knowledge, there have been no previous studies evaluating the risk of injury with the knee in the standard operational figure-of-4 position with joint dilatation in arthroscopic lateral meniscal repair. Purpose: To evaluate and compare the risk of peroneal nerve injury and establish the safe and danger zones in repairing the lateral meniscus through the anteromedial, anterolateral, or transpatellar portal in relation to the medial and lateral borders of the popliteal tendon (PT). Study Design: Descriptive laboratory study. Methods: Using axial magnetic resonance imaging (MRI) studies of knees in the figure-of-4 position with joint fluid dilatation at the level of the lateral meniscus, we drew direct lines to simulate a straight all–inside meniscal repair device deployed from the anteromedial, anterolateral, and transpatellar portals to the medial and lateral borders of the PT. If the line passed through or touched the peroneal nerve, a risk of iatrogenic peroneal nerve injury was noted, and measurements were made to determine the safe and danger zones for peroneal nerve injury in relation to the medial or lateral border of the PT. Results: Axial MRI images of 29 adult patients were reviewed. Repairing the lateral meniscus through the anteromedial portal in relation to the lateral border of the PT and through the anterolateral portal in relation to the medial border of the PT had a 0% risk of peroneal nerve injury. The “safe zone” in relation to the medial border of the PT through the anterolateral portal was between the medial border of the PT and 9.62 ± 4.60 mm medially from the same border. Conclusion: It is safe to repair the body of the lateral meniscus through the anteromedial portal in the area lateral to the lateral border of the PT or through the anterolateral portal in the area medial to the medial border of the PT. Clinical Relevance: There is a risk of iatrogenic peroneal nerve injury during lateral meniscal repair. Thus, we recommend repairing the lateral meniscal tissue through the anteromedial portal in the area lateral to the lateral border of the PT and using the anterolateral portal in the area medial to the medial border of the PT, as neither of these approaches resulted in peroneal nerve injury. Additionally, the surgeon can decrease this risk by repairing the meniscal tissue using the all–inside meniscal device in the safe zone area.

Meniscus Tear Types and Early Failures in Pediaric Patients: Descriptive EPIDemiologic Analysis from the Score Multi-Center Quality Imrovment Project.

Background:Meniscal tears have been reported at higher rates in the pediatric patient in recent years. Meniscus repair to restore meniscus function may be invaluable to the long-term health of the knee.Hypothesis/Purpose:To describe demographic characteristics, tear types, and surgical techniques for meniscus repair in pediatric patients, including risk factors for early repair failure.Methods:A multi-center quality improvement registry (16 institutions, 26 surgeons) monitoring the safety of meniscus repairs was reviewed. Audit processes using CPT codes were designed to ensure that all consecutive cases were prospectively entered on patients <19 years old into a HIPAA-compliant electronic platform. Each meniscus repair case with a complication form was secondarily reviewed to ensure consistency of identification and grading. Demographics, tear type, repair technique, and implant type, when applicable, were included, and a common cause analysis was performed to evaluate risk factors for early repair failures.Results:1230 meniscus repair cases (mean age 15.2, 5-19; Female 43.8%) were identified, consisting of 49.0% lateral meniscus repair (LMR), 36.0% medial meniscus repair (MMR), and 15.0% LMR+MMR. The majority (69.7%) were performed in conjunction with either ACL reconstruction (ACLr) or tibial spine repair (TSr). In both LMR and MMR, the most common tear type, technique, and implant were longitudinal/vertical tear (50.3%, 80.0%, respectively), all-inside repair (69.3%, 68.9%, respectively), and Smith & Nephew Fast-Fix 360 (37.8%, 36.8%, respectively). An inside-out repair was performed twice as often in both LMR and MMR when performed in isolation without an ACLr or TSr. For both LMR and MMR, surgeons used an average of 2 sutures/devices (38.0%) with 6.5% involving 10+ sutures/implants. Variation in meniscus repair techniques was seen between tear types, displacement, and location (Tables 1, 2). Radial tears were uncommon in the MM (2.7%), but were commonly treated in the LM (12.32%) using all-inside (42.1%), inside-out (30.2%), and outside-in (19.7%) techniques. Meniscus tears with displacement were seen in 35.2% of MM tears and 25.3% of LM tears, with anterior displacement being the most common direction. For both LMR and MMR, the most common technique for tears with displacement was all-inside (58.4%). There were 15 early (<8 months) repair failures (1.2%), most common type and technique of which were MMR (73.3%) and all-inside (73.3%).Conclusion:The techniques utilized for pediatric meniscus tears depend upon tear type, displacement, and whether performed in conjunction with an ACLr or TSr. MMR performed with all-inside technique may be at risk for early failure.Table 1: Pediatric Lateral Meniscus tear and repair types from SCORE (a multi-center quality improvement registry)Table 2:Pediatric Medial Meniscus tear and repair types from SCORE (a multi-center quality improvement registry)

Paper 17: Optimal Tibial Tunnel Placement for Medial and Lateral Meniscal Root Repair in the Setting of Multiligament Reconstructions of the Knee

Objectives:Although the risk of tibial tunnel convergence in the setting of multiligament reconstruction has been reported in the literature, the risk of tunnel convergence in the setting of posterior cruciate ligament (PCL), anterior cruciate ligament (ACL), and medial and lateral meniscal root repair has not been defined. The purpose of this study was to examine the risk of tunnel convergence and to determine optimal tunnel placement for ACL and PCL reconstruction performed in conjunction with posterior medial and lateral meniscal root repairs in the proximal tibia.Methods:Three-dimensional tibial models were created using computed tomography scans of twenty cadaveric specimens. After determining optimal tunnel entry and exit points for ACL and PCL reconstructions, and medial and lateral meniscal root repair on the models, Mimics software was used to create root tunnels. The meniscal root repair tunnels were then re-oriented to be parallel to the ACL tunnel. The initial and re-oriented configurations are illustrated in Figure 1. Tunnel convergence risk was analyzed with single and double tunnel techniques in both case scenarios.Results:There were no cases of convergence between the ACL and medial meniscal root tunnels in any of the configurations. The greatest distance between the tunnels was achieved with the single tunnel technique in parallel orientation (12.09 ± 2.78 mm). All specimens demonstrated convergence between the ACL and lateral meniscal root tunnels when the sagittal plane entry was not taken into consideration and only the anatomic root attachment was accounted for, for single and double tunnel techniques, but no convergence was seen between these tunnels with the parallel orientation in the sagittal plane. Figure 2 illustrates the reduction in the convergence risk when the meniscal root tunnels are reoriented as parallel to the ACL tunnel. There were no cases of convergence between the PCL and medial meniscal root tunnels in the original orientation, but 2/20 specimens demonstrated convergence in the parallel orientation with the double tunnel technique and no cases of convergence in the single tunnel technique. The PCL and lateral meniscal root tunnels did not demonstrate convergence in any configuration. Table 1 demonstrates the mean, minimum and maximum distances of each tunnel configuration as well as the number of cases where the distance between tunnels was <2mm. A summary of the preferred tunnel configurations for each setting, ranked by greatest tunnel distance conferred and cases of convergence, is reported in Table 2.Conclusions:There is a high risk of convergence between ACL and posterior meniscus root tunnels. Re-orienting meniscal root tunnels parallel to ACL tunnels may help reduce this risk. When PCL reconstruction is performed with ACL reconstruction and medial and lateral meniscal root repair, the single tunnel root repair technique may pose less risk over the double tunnel technique to prevent tunnel convergence between the meniscal root repair and PCL tunnels in the tibia.Figure 1. Illustration of the reconstruction of the tunnels. (A) Initial orientation where the meniscal root tunnels’ entry points on the anteromedial aspect of the tibia were created above the ACL tunnel. (B) The meniscal root tunnels re-orientated and were placed parallel to that of the ACL and aimed to exit at the anatomic attachment of the posterior roots of the meniscus. (Gold guide for the creation of the ACL tunnel and silver guide for the creation of the meniscal root tunnel)

Paper 18: Treatment of Lateral Meniscus Tears Influences OA Rate following ACL Reconstruction at 9-year Follow-Up

Objectives:Recent studies have described an increased risk of osteoarthritis (OA) following ACL reconstruction (ACLR). Systematic reviews have suggested that meniscal pathology, which occurs in up to 60% of patients with ACL injury, increases this risk. The purpose of this study was to determine the influence of lateral meniscus tears and repair versus partial lateral meniscectomy on the risk of OA in patients following ACLR.Methods:All patients who underwent primary autograft or allograft bone-patellar tendon-bone (BPTB) transtibial ACLR by a single surgeon between 1999-2019, were identified. Revision ACLR, multi-ligamentous reconstructions, and patients with less than 2-year imaging follow-up were excluded. Patients with lateral meniscus pathology at the time of ACLR were identified and treatment (e.g. lateral meniscectomy or lateral meniscus tear) was extracted. OA was defined at follow-up as Kellgren-Lawrence (KL) grade III-IV on plain radiographs. Chi-square tests assessed differences in incidence rates (p<0.05).Results:A consecutive series of 113 patients (57 males, 56 females; age 35.7±11.9 years) with BPTB ACLR were included. The mean follow-up was 9±5 years. The prevalence of lateral meniscus tears was 60.2% (68/113) and the prevalence of lateral compartment OA at follow-up was 14% (16/113) Patients with a lateral meniscus tear were 4.7 times more likely to develop OA compared to patients with no lateral meniscus tear. 20.6% of patients (14/68) with lateral meniscus tear developed lateral OA compared to 4.4% of patients (2/45) without lateral meniscus tear (p=0.0158). Patients who underwent lateral meniscal repair (n=16) had significantly lower prevalence of OA (0/16) compared to patients who underwent lateral meniscectomy (14/52) (p=0.0196).Conclusions:At nine-year follow-up, patients with a lateral meniscus tear at time of ACLR were more likely to develop OA compared to patients with no lateral meniscus tear and patients treated with partial meniscectomy had higher prevalence of OA compared to those treated with meniscus repair. In patients who require ACLR, care should be taken in evaluating and treating the lateral meniscus to decrease the likelihood of the development of OA. We believe lateral meniscal repair is essential for lateral meniscus tears at the time ACL reconstruction to help avoid development of OA.Figure 1.

Accelerated Vs Conservative Rehabilitation Following Meniscus Repair In Pediatric Pateints With Or Without Acl Reconstruction

Background:There are variations in postoperative restrictions following pediatric meniscus repairs, whether they are performed in isolation or at the time of an anterior cruciate ligament reconstruction (ACLR).Hypothesis:We hypothesized that there would be no difference in failure rates when comparing accelerated versus conservative post-operative management following both isolated meniscus repairs and meniscus repairs performed at the time of an ACLR.Methods:A retrospective chart review was performed to investigate pediatric patients who underwent an isolated medial or lateral meniscus repair with or without a combined primary ACLR from January 2010 to January 2019 within a large children’s health system among eight different surgeons who all utilized different rehabilitation protocols. Patient outcomes of a need to return to the operating room secondary to failure of meniscus repair were analyzed with regard to accelerated versus conservative rehabilitation. Accelerated management included early unrestricted weightbearing within 3 weeks, unrestricted range of motion in a brace within 6 weeks, less than 6 weeks of brace use, initiation of outpatient physical therapy within 6 weeks, and returning to play sports earlier than 16 weeks for the isolated meniscus group or earlier than 30 weeks for the combined group.Results:138 patients aged 14.1 + 2.9 years had an isolated meniscus repair with 24.6 + 16.8 weeks of follow-up and a 17% failure rate, and 190 patients aged 15.5 + 1.6 years had a meniscus repair at the time of an ACLR with follow-up of 42.9 + 27.4 weeks and a 13% failure rate. A binomial logistic regression showed no differences in failure rates for accelerated versus conservative weightbearing restrictions, brace immobilization, physical therapy timing, or return to play timing (Table 1).Conclusion:These findings demonstrate that pediatric meniscus repair failure rates remain similar despite wide variations in postoperative management, whether performed in isolation or at the time of an ACLR. Further investigation should be directed towards determining optimal post-operative management protocols that attempt to strike a balance between protecting the surgical repair and avoiding measures that may be overly burdensome to the patient or add unnecessary treatment costs.Table 1.Results of binomial logistic regressions used to predict failure rates

Biomechanics of the lateral meniscus: evidences from narrative review.

Lateral meniscus plays a crucial role in the knee stability and function. Although complex settings are required for lateral meniscus biomechanical assessment, such characteristics have been investigated over time to optimize the daily clinical practice surgical procedure. The aim of the present study was to provide an overview of literature knowledge regarding the biomechanics of lateral meniscus and give further insights about novel experimental analyses. Studies regarding lateral meniscus mobility, effect on knee laxity, and contact mechanics were included in the review. The effect of meniscal lesion, meniscal repair, partial meniscectomy, and meniscus allograft transplantation were retrieved for either in vivo, cadaveric, or in-silico computational settings. Knee laxity was evaluated both in presence of isolated meniscal tears and in anterior cruciate ligament (ACL) deficient knees. Surgical navigation systems and robots were mainly used for the investigations in vivo and in cadaveric studies, while accelerometers emerged as an alternative for ambulatory assessments. Contact mechanics was only assessed in cadaveric and computational studies. Great effort has been put into exploring lateral meniscus biomechanics from multiple perspectives. Strong evidence emerged regarding the importance of lateral meniscus repair: increased knee stability at high degrees of knee flexion and reduction of peak contact pressures on tibial cartilage were the most reported benefits. The meniscus allograft transplantation also emerged as a concrete solution for irreparable tears and further studies are needed to investigate its long-term influence on knee stability.

Prospective Consecutive Clinical Outcomes After Transtibial Root Repair for Posterior Meniscal Root Tears: A Multicenter Study.

Background:Prospective evaluation of clinical outcomes after posterior meniscal root repair utilizing a transtibial pullout technique is limited, and factors that may contribute to outcomes are unclear.Hypothesis:It was hypothesized that there would be an overall significant improvement in outcomes after root repair and that differences in clinical outcomes would correlate with age, body mass index (BMI), sex, and meniscal extrusion.Study Design:Case-control study; Level of evidence, 3.Methods:Consecutive patients undergoing transtibial medial or lateral meniscal root repair were enrolled prospectively at 2 orthopaedic centers between March 2017 and January 2019. Pre- and postoperative magnetic resonance imaging (MRI) were obtained to assess for meniscal healing, quantification of extrusion, articular cartilage grade, and subchondral bone changes. Patient-reported outcomes including International Knee Documentation Committee (IKDC) scores, Tegner activity scale, and visual analog scale (VAS) for pain were collected preoperatively and 2 years postoperatively. Patients were then subdivided by clinical and demographic characteristics to determine factors associated with clinical outcomes.Results:Included were 45 patients (29 female, 16 male; mean age, 42.3 ± 12.9 years; mean BMI, 31.6 kg/m2) who underwent 47 meniscal root repairs (29 medial and 16 lateral; 2 had both). Significant improvements at 2-year follow-up were seen in IKDC score (41.1 vs 78.4; P < .001), Tegner activity level (3 vs 4; P < .001), and VAS pain (2.8 vs 0.7; P < .001). BMI, preoperative malalignment, cartilage status, and progressive meniscus extrusion (Δ = 0.7 mm) did not have a negative impact on IKDC and Tegner scores 2 years postoperatively. Age greater than or equal to 50 years and extrusion pre- and postoperatively were associated with decreased Tegner scores. Progressive meniscal extrusion was associated with a decreased overall improvement in Tegner scores.Conclusion:Transtibial root repair for medial and lateral posterior meniscal root tears demonstrated significantly improved clinical outcomes at 2 years postoperatively. Increased age, increased BMI, cartilage status, and meniscal extrusion did not have a negative impact on short-term functional outcomes (IKDC), but age greater than or equal to 50 years and extrusion negatively influenced patient activity level (Tegner).Registration:NCT03037242 (ClinicalTrials.gov identifier).

1664 A rare case of Stenotrophomas maltophilia affecting an ACL Endobutton: A Case Report and Review of the literature

Abstract Background Stenotrophomas maltophilia (SM) is a ubiquitous opportunistic gram-negative bacillus known to cause hospital acquired infections, commonly in immunosuppressed individuals. However, occurrence of this microorganism is rarely reported in the musculoskeletal system. We report a case of a young healthy man with recurrent knee swelling caused by SM. This organism has been reported to form biofilms over orthopaedic implants, with increased resistance to antibiotic therapy, making it difficult to eradicate once established. Case Report A 34-year-old man with psoriasis and asthma presented with right knee swelling and pain, and no history of preceding trauma or fever. He has a past surgical history of anterior cruciate ligament tear and underwent reconstruction with an endobutton two years prior, and a lateral meniscal repair treated in the previous year. At presentation, he was apyrexial and was noted to have a moderate right knee effusion. Initial radiographic imaging identified a large joint effusion with no obvious evidence of bone destruction, laboratory studies also showed a raised white cell count of 11.4 *10^9/L, C-reactive protein of 54mg/L and aspiration cultures were negative. He subsequently underwent numerous washouts, and removal of endobutton with open synovial biopsy which showed SM. The organism was sensitive to cotrimoxazole. The patient had appropriate antibiotics with resolution of symptoms, however he still presented with recurrence. Conclusions The persistence of SM despite intervention makes it difficult to treat. Although a rare organism, surgeons should consider it as a differential in recurring knee effusion with orthopaedic implants, and institute early and appropriate management for best outcomes.

Deep flexion helps to avoid popliteal artery injury during all-inside lateral meniscal repair: A cadaveric study

BackgroundArthroscopic meniscus repair rarely leads to major complications such as popliteal artery injury. The distance between the suturing device and the popliteal artery, and the risk of popliteal artery injury at different knee flexion angles during all-inside lateral meniscal repair remain unclear. MethodsAll-inside devices were inserted into 10 human cadaveric knees at the posterior horn of the lateral meniscus through the anterolateral portal at 60°, 90°, and 120° knee flexion; posterior segment of the lateral meniscus through the anterolateral portal at 60°, 90°, and 120°; and anteromedial portal at 90°. Distance and positional relationship between the device and popliteal artery were measured radiographically. ResultsIn posterior horn repair through the anterolateral portal, the median distance increased from 5.7 mm at 60° to 9.1 mm at 90° (P = 0.63) and 18.0 mm at 120° (P = 0.02). The device pushed the wire at 60° in three cases, 90° in one case, and 120° in 0 cases. In posterior segment repair through the anterolateral portal, the median distance was 12.6 mm at 60°, 10.4 mm at 90°, and 18.3 mm at 120° (P = 0.08). The median distance at 90° was 18.1 mm through the anteromedial portal, the same as that at 120° through the anterolateral portal (P = 0.43), but greater than that at 90° through the anterolateral portal (P = 0.04). The wire was not pushed in any case. ConclusionAlthough all-inside repair of the posterior part of the lateral meniscus through the anterolateral portal is risky, deeper knee flexion reduces the risk of popliteal artery injury.

The Danger Zone for Iatrogenic Neurovascular Injury in All-Inside Lateral Meniscal Repair in Relation to the Popliteal Tendon: An MRI Study.

Background:Lateral meniscal repair can endanger the nearby neurovascular structure (peroneal nerve or popliteal artery). To our knowledge, there have been no studies to evaluate the danger zone of all-inside meniscal repair through the anteromedial (AM) and anterolateral (AL) portals in relation to the medial and lateral edges of the popliteal tendon (PT).Purpose:To establish the risk of neurovascular injury and the danger zone in repairing the lateral meniscus in relation to the medial and lateral edges of the PT.Study Design:Descriptive laboratory study.Methods:Using axial magnetic resonance imaging (MRI) studies at the level of the lateral meniscus, lines were drawn to simulate a straight, all-inside meniscal repair device, drawn from the AM and AL portals to both the medial and lateral edges of the PT. In cases in which the line passed through the neurovascular structure, a risk of iatrogenic neurovascular injury was deemed, and measurements were made to determine the danger zones of neurovascular injury in relation to the medial or lateral edges of the PT.Results:Axial MRI images of 240 adult patients were reviewed retrospectively. Repairing the body of the lateral meniscus through the AM portal had a greater risk of neurovascular injury than repairs made through the AL portal in relation to the medial edge of the PT (P = .006). The danger zone in repairing the lateral meniscus through the AM portal extended 1.82 ± 1.68 mm laterally from the lateral edge of the PT and 3.13 ± 2.45 mm medially from the medial edge of the PT. Through the AL portal, the danger zone extended 2.81 ± 1.94 mm laterally from the lateral edge of the PT and 1.39 ± 1.53 mm medially from the medial edge of the PT.Conclusion:Repairing the lateral meniscus through either the AM or the AL portals in relation to the PT can endanger the peroneal nerve or popliteal artery.Clinical Relevance:The surgeon can minimize the risk of iatrogenic neurovascular injury in lateral meniscal repair by avoiding using the all-inside meniscal device in the danger zone area as described in this study.

Lateral Meniscal Tears in Young Patients: A Comparison of Meniscectomy and Surgical Repair.

Background:Meniscal tears are common in active patients, but treatment trends and surgical outcomes in young patients with lateral meniscal tears are lacking.Purpose:To evaluate treatment trends, outcomes, and failure rates in young patients with lateral meniscal tears.Study Design:Cohort study; Level of evidence, 3.Methods:Patients aged ≤25 years treated surgically for isolated lateral meniscal tears from 2001 to 2017 were identified. Treatment trends were compared over time. International Knee Documentation Committee (IKDC) scores and failure rates were compared by treatment modality (meniscectomy vs meniscal repair). Failure was defined as reoperation, symptomatic osteoarthritis, or a severely abnormal IKDC score. Univariate regression analyses were performed to predict failure and IKDC scores based on treatment, type and location of tear, or extent of meniscectomy.Results:Included were 217 patients (226 knees) with a mean age of 17.4 years (range, 7-25 years); of these patients, 144 knees (64%) were treated with meniscectomy and 82 knees (36%) with meniscal repair. Treatment with repair increased over time compared with meniscectomy (P < .001). At a minimum 2-year follow-up (mean, 6.1 ± 3.9 years), 107 patients (110 knees) had IKDC scores, and analysis indicated that although scores in both groups improved from pre- to postoperatively (repair: from 69.5 ± 13.3 to 97.4 ± 4.3; meniscectomy: from 75.7 ± 9.0 to 97.3 ± 3.9; P < .001 for both), improvement in IKDC score was greater after repair (27.9 ± 13.9) versus meniscectomy (21.6 ± 9.4) (P = .005). Included in the failure analysis were 184 patients (192 knees) at a mean follow-up of 8.4 ± 4.4 years. The rates of reoperation, symptomatic osteoarthritis, and failure were not significantly different between the meniscectomy and repair groups.Conclusion:An increase was seen in the rate of isolated lateral meniscal tear repair in young patients. IKDC score improvement was greater after repair than meniscectomy, although postoperative IKDC scores were similar. Symptomatic arthritis, reoperation, and failure rates were similar between groups; however, there was a trend for increased arthritis symptoms in patients treated with meniscectomy, especially total meniscectomy. Treatment modality, type and location of tear, and amount of meniscus removed were not predictive of final IKDC scores or failure.

A Surgical Algorithm According to Pivot-Shift Grade in Patients With ACL Injury: A Prospective Clinical and Radiological Evaluation

Background:Some patients have a positive pivot-shift finding and rotational instability after anterior cruciate ligament (ACL) reconstruction (ACLR). Three major pathologies known to affect the pivot-shift examination include ACL tear, anterolateral ligament injury, and loss of posterior lateral meniscus root function.Purpose:To describe a surgical algorithm determining indications for lateral extra-articular tenodesis (LET) based on intraoperative pivot-shift examination to prevent postoperative pivot shift and rotational instability and to evaluate the 2-year clinical and functional outcomes.Study Design:Case series; Level of evidence, 4.Methods:The study included 47 consecutive patients (39 men and 8 women) who underwent operative treatment for ACL injury between 2016 and 2017. Pivot-shift examination was performed under anesthesia, and the pivot shift was graded as grade 1 (glide), grade 2 (clunk), or grade 3 (gross). According to the surgical algorithm, single-bundle ACLR was performed in patients with grade 1 pivot shift. In patients with grade 2 with loss of posterior lateral meniscus root function, concurrent lateral meniscal repair was performed, and in patients with grade 2 with an intact lateral meniscus posterior root, concurrent extra-articular iliotibial band tenodesis was performed. Patients with grade 3 underwent ACLR, lateral meniscal repair, and LET. Clinical and radiographic evaluations were performed.Results:The mean age was 27.2 years (range, 16-56 years). In total, 26 (55.3%) patients were evaluated as having pivot-shift grade 1; 16 (34%) patients, grade 2; and 5 (10.6%) patients, grade 3. A total of 7 (14.9%) patients underwent LET in addition to ACLR. Two of these patients had pivot-shift grade 2, and LET was performed since the lateral meniscus posterior root was intact. In 14 of 16 patients with grade 2, lateral meniscus root disruption was detected, and lateral meniscal repair was performed. One patient was excluded from the further follow-up because of graft failure. At a mean postoperative follow-up of 29 months in 46 patients, the pivot-shift examination was negative in all patients. The mean Lysholm and International Knee Documentation Committee subjective scores were 95.35 ± 4.40 and 82.87 ± 9.36, respectively. Radiographic evidence of osteoarthritis was not detected.Conclusion:Only 14.9% of patients needed LET. With proper ACL, lateral meniscal, and anterolateral ligament surgery, it was possible to prevent positive pivot-shift findings postoperatively.

Narrative review of lateral meniscus repair: techniques and outcomes

Narrative review of lateral meniscus repair: techniques and outcomes

Age, time from injury to surgery and quadriceps strength affect the risk of revision surgery after primary ACL reconstruction

PurposeTo identify preoperative, intraoperative and postoperative factors associated with revision anterior cruciate ligament reconstruction (ACLR) within 2 years of primary ACLR.MethodsPatients who underwent primary ACLR at our institution, from January 2005 to March 2017, were identified. The primary outcome was the occurrence of revision ACLR within 2 years of primary ACLR. Univariate and multivariate logistic regression analyses were used to evaluate preoperative [age, gender, body mass index (BMI), time from injury to surgery, pre-injury Tegner activity level], intraoperative [graft type, graft diameter, medial meniscus (MM) and lateral meniscus (LM) resection or repair, cartilage injury] and postoperative [side-to-side (STS) anterior laxity, limb symmetry index (LSI) for quadriceps and hamstring strength and single-leg-hop test performance at 6 months] risk factors for revision ACLR.ResultsA total of 6,510 primary ACLRs were included. The overall incidence of revision ACLR within 2 years was 2.5%. Univariate analysis showed that age < 25 years, BMI < 25 kg/m2, time from injury to surgery < 12 months, pre-injury Tegner activity level ≥ 6, LM repair, STS laxity > 5 mm, quadriceps strength and single-leg-hop test LSI of ≥ 90% increased the odds; whereas, MM resection and the presence of a cartilage injury reduced the odds of revision ACLR. Multivariate analysis revealed that revision ACLR was significantly related only to age < 25 years (OR 6.25; 95% CI 3.57–11.11; P < 0.001), time from injury to surgery < 12 months (OR 2.27; 95% CI 1.25–4.17; P = 0.007) and quadriceps strength LSI of ≥ 90% (OR 1.70; 95% CI 1.16–2.49; P = 0.006).ConclusionAge < 25 years, time from injury to surgery < 12 months and 6-month quadriceps strength LSI of ≥ 90% increased the odds of revision ACLR within 2 years of primary ACLR. Understanding the risk factors for revision ACLR has important implications when it comes to the appropriate counseling for primary ACLR. In this study, a large spectrum of potential risk factors for revision ACLR was analyzed in a large cohort. Advising patients regarding the results of an ACLR should also include potential risk factors for revision surgery.Level of evidence III.