Citations

AbstractBone marrow edema (BME) can be a late finding in osteoarthritis or a sign of subchondral insufficiency. The purpose of this study was to describe the magnetic resonance imaging (MRI) finding we refer to as “osteomeniscal impact edema” (OMIE), or reactive BME adjacent to a displaced meniscus flap tear. In addition, this edema pattern is compared with a control group of medial meniscus posterior root tears (MMPRT) with subchondral insufficiency edema. MRI records from 2000 to 2017 were retrospectively reviewed for studies that showed the presence of a medial meniscus displaced flap tear and an adjacent area of BME. The selected MRIs were matched to an equal number of MMPRT MRI studies. All MRI studies were assessed for cartilage surface grade using the modified Outerbridge classification system and for the extent of accompanying structural abnormalities using the whole-organ magnetic resonance imaging score. Descriptive statistics and hypothesis testing were utilized to compare the MRI findings between groups. Twenty-two flap tear (OMIE group) patients with a mean age of 57 (SD: 15) and 22 root tear (MMPRT) group patients with a mean age of 61 (SD: 10) were included. MRIs in the OMIE group showed a distinctive pattern of focal, peripheral edema adjacent to the meniscus flap tear, compared with more diffuse, central edema in the MMPRT group. Quantitatively, MRIs of the MMPRT group showed significantly worse mean femoral Outerbridge scores (3.72 vs. 2.68, p < 0.0001), more severe central (1.63 vs. 0.5, p = 0.0007) and posterior (0.31 vs. 0.0, p = 0.04) subchondral edema grades, and a higher incidence of tibial subchondral fractures (3 vs. 0, p = 0.036). Meniscus flap tears may present with a distinct MRI pattern of focal, adjacent, peripheral edema, which we refer to as OMIE. Patients with meniscus flap tears showed significantly less arthritic change, lower subchondral edema grades, and a lower incidence of insufficiency fractures and subchondral collapse compared with the diffuse overload edema pattern found with root tears. The Level of Evidence for this study is III.

Unfortunately, the middle name of Olufemi R. Ayeni was accidentally omitted in the original publication and the author name is corrected here. The original article has been corrected.

Background: Meniscal repair is desirable over resection to prevent postmeniscectomy arthritis, especially among young and active patients. However, long-term data are currently lacking following isolated meniscal repair, particularly in the pediatric population. Purpose/Hypothesis: To report long-term follow-up of isolated meniscal tears treated by meniscal repair in a pediatric and adolescent population and to compare those results with previous midterm follow-up data reported. The authors hypothesized that these patients would have satisfactory function and reoperation rates at long-term follow-up. Study Design: Case series; Level of evidence, 4. Methods: Forty-four patients aged ≤18 years undergoing repair of an isolated meniscal tear (without concomitant anterior cruciate ligament injury) between 1990 and 2005 were included. At the time of final follow-up, recurrent tear, reoperations, and International Knee Documentation Committee (IKDC) and Tegner scores were determined. With logistic regression, the overall failure among tear types was calculated. Wilcoxon rank sum analysis were performed to calculate the differences in clinical outcome for different time points, and Spearman coefficients were calculated for Tegner and IKDC with different variables. Results: At a mean follow-up of 17.6 years (range, 13.1-25.9 years), 32 patients with 33 isolated meniscal repairs (29 male, 3 female) with a mean age of 16.1 years (range, 9.9-18.7 years) at surgery were included in this study. At early follow-up, the overall failure rate was 14 of 33 (42%); complex tears (80%) and bucket-handle tears (47%) had higher overall failure rates when compared with simple tears (18.2%), although only complex tears had a significantly higher failure rate. However, no further failures occurred since midterm follow-up with any tear type. At final follow-up, the mean IKDC score was 92.3, which was significantly increased when compared with preoperative (65.3, P < .0001) and midterm (90.2, P = .01) scores. The mean Tegner score (6.5) was significantly lower than both preoperative (8.3, P < .0001) and midterm (8.4, P < .0001) scores. There was no difference in Tegner or IKDC score for patients with successful versus failed repair. Conclusion: In conclusion, while there was a high early failure rate, this study demonstrated overall good to excellent long-term clinical outcomes after isolated meniscal repair in an adolescent population, even for those requiring reoperation. Early failure and reoperation rates were variable, depending on tear type, with complex multiplanar tears having more failures at short-term follow-up. However, at long-term follow-up, IKDC and Tegner scores were not significantly different for those with complex tears as compared with other tear types.

AbstractPurposeThe aim of this review was to compare the clinical outcomes of anterior cruciate ligament reconstruction (ACLR) with either meniscal repair or meniscectomy for concomitant meniscal injury. The primary hypothesis was that short‐term clinical outcomes (≤ 2‐year follow‐up) for ACLR concomitant with either meniscal repair or resection would be similar. The secondary hypothesis was that ACLR with meniscal repair would result in better longer term outcomes compared with meniscal resection.MethodsThe authors searched two online databases (EMBASE and MEDLINE) from inception until March 2018 for the literature on ACLR and concurrent meniscal surgery. Two reviewers systematically screened studies in duplicate, independently, and based on a priori criteria. Quality assessment was also performed in duplicate. The Knee injury and Osteoarthritis Outcome Score (KOOS) sub‐scale scores at 2 years post‐operatively were combined in a meta‐analysis of proportions using a random‐effects model.ResultsOf 2566 initial studies, 25 studies satisfied full‐text inclusion criteria. Mean follow‐up was 2.09 years, with a total sample of 37,087 subjects including controls. The meta‐analysis demonstrated equivocal results at 2 years, except for KOOS symptom scores which favoured meniscal resection over repair. Mean KT‐1000 side‐to‐side difference (SSD) scores were 1.51 ± 0.60 mm for meniscal repair, 1.96 ± 0.36 mm for meniscal resection, and 1.58 ± 0.20 for control patients (isolated ACLR). Medial meniscal repair showed decreased anterior knee joint laxity compared to medial meniscal resection (P < 0.001). Patients with meniscal repair had higher rates of re‐operation (13.3% vs 0.8% for meniscal resection, P < 0.001).ConclusionPatients with ACLR combined with meniscal resection demonstrate better symptoms at 2‐year follow‐up compared to patients with ACLR combined with meniscal repair. ACLR combined with meniscal repair results in decreased anterior knee joint laxity with evidence of improved patient‐reported outcomes in the long term, but also higher re‐operation rates.Level of evidenceIII.

Background: Surgical reconstruction of the anterior cruciate ligament (ACL) is one of the most common orthopaedic procedures, with an estimated 100,000 to 175,000 procedures performed annually. Recently, the all-inside reconstruction technique has come into favor and is theorized to be superior to the complete tibial tunnel technique. Purpose: To compare clinical and patient-reported outcomes (PROs) for hamstring autograft ACL reconstruction (ACLR) performed with an all-inside versus a complete tibial tunnel technique. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent hamstring autograft ACLR via either an all-inside approach (femoral and tibial sockets) or a complete tibial tunnel approach (femoral socket and full-length, transtibial tunnel) at a single institution between July 2011 and July 2015 were reviewed. Demographic information, preoperative comorbidities, surgical details, physical examination findings, and follow-up outcomes were extracted from the medical record. Physical examination data included pivot-shift, Lachman, and range of motion examinations, whereas PROs included the Tegner activity scale, Lysholm score, and International Knee Documentation Committee (IKDC) score at a minimum of 2 years after surgery. Return to sport and risk factors for failure were analyzed. Results: A total of 82 patients (mean ± SD age, 25.8 ± 10.2 years) who underwent all-inside reconstruction (median PRO follow-up, 30.1 months; range, 24.7-72.9 months) and 54 patients (mean ± SD age, 21.1 ± 7.3 years) who underwent complete tibial tunnel reconstruction (median PRO follow-up, 25.8 months; range, 23.9-74.5 months) met the inclusion criteria. PRO scores at latest follow-up were comparable between the all-inside versus the complete tibial tunnel groups (Lysholm score, 93.8 vs 94.4, P = .621; IKDC score, 93.5 vs 93.3, P = .497; Tegner activity score, 6.4 vs 6.8, P = .048). Complications (including graft failure) were experienced by 20% of patients in the all-inside group compared with 24% in the complete tibial tunnel group ( P = .530). Graft failure before the final follow-up was experienced by 10% of patients in the all-inside group compared with 19% in the complete tibial tunnel group ( P = .200). Mean return to sport was 12.5 months in the all-inside group versus 9.9 months in the complete tibial tunnel group ( P = .028). Conclusion: All-inside and complete tibial tunnel hamstring autograft ACLR resulted in excellent physical examination findings and PROs at minimum 2-year follow-up. Both techniques successfully restored knee stability and patient function.

Purpose To describe the clinical history of a series of primary, lateral patellar dislocations and determine long‐term predictors of recurrent instability while accounting for patients undergoing early operative management. Methods A large geographic database of more than 500,000 patients was used to identify patients who sustained a first‐time lateral patellar dislocation between 1990 and 2010. Charts were individually reviewed to document demographics, radiographic measures including tibial tubercle to trochlear groove distance (TT‐TG) and patellar length (PL), recurrent episodes of instability, and patellar stabilization surgery. A risk score that accounted for early surgical management was calculated using Fine and Gray competing risk regression, and its ability to stratify patients was examined using cumulative incidence curves. Results Eighty‐one patients (mean age 19.9 ± 9.4 years, 38 male, 43 female) were identified and followed for a mean of 10.1 years (range 4.1‐20.2). Thirty‐eight patients (46.9%) experienced an episode of recurrent instability and 30 (37.0%) underwent patellar stabilization surgery, including 7 who did so before recurrent dislocation. A multivariate, statistically derived scoring system, the Recurrent Instability of the Patella Score (RIP Score), that employed age, skeletal maturity, trochlear dysplasia, and TT‐TG/PL ratio to predict recurrent instability while accounting for patients managed surgically, was generated. The resulting RIP score stratified patients into low‐, intermediate‐, and high‐risk categories, with 0.0%, 30.6%, and 79.2% 10‐year recurrent instability rates, respectively ( P = .000004), and an area under the curve of 0.875 ( P = .00002). Conclusions Patients who sustain a first‐time, lateral patellar dislocation can be readily classified into low‐, intermediate‐, and high‐risk categories employing the RIP score based on age, skeletal maturity, trochlear dysplasia, and TT‐TG/PL ratio. This long‐term risk stratification holds significant potential clinical utility for determination of patients who are at high risk for recurrent instability after primary patellar dislocation. Level of Evidence Level III, retrospective comparative study.

Background: Avulsion fractures involving the tibial eminence are considered equivalent in terms of the cause to anterior cruciate ligament (ACL) tears; however, there are limited data comparing the outcomes of adolescent patients undergoing surgical fixation of a tibial eminence fracture (TEF) with those undergoing ACL reconstruction. Purpose: To compare the clinical outcomes, subsequent ACL injury rates, and activity levels between adolescent patients who underwent TEF fixation with patients with midsubstance ACL tears who required acute reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: This study included a group of patients with TEFs treated with surgical fixation matched to a group of similar patients with ACL tears treated with reconstruction between the years 2001 and 2015. Data regarding the initial injury, surgical intervention, ACL/ACL graft injury rates, and physical examination findings were recorded. Clinical and functional outcomes were obtained using a physical examination, the International Knee Documentation Committee (IKDC) subjective score, the Lysholm score, and the Tegner activity score. Results: Sixty patients with a mean follow-up of 57.7 months (range, 24-206 months) were included; 20 patients (11 male, 9 female; mean age, 11.9 years [range, 7-15 years]) who underwent surgical fixation for a TEF were matched to a group of 40 patients (23 male, 17 female; mean age, 12.5 years [range, 8-5 years]) who underwent reconstruction for ACL tears. The TEF group demonstrated significantly lower postoperative IKDC scores (TEF group, 94.0; ACL group, 97.2; P = .04) and Lysholm scores (TEF group, 92.4; ACL group, 96.9; P = .02). The TEF group returned to sport 119 days sooner ( P < .01), but there was no difference in postoperative Tegner scores (TEF group, 7.3; ACL group, 7.6; P = .16). The TEF group demonstrated increased postoperative anterior laxity ( P = .02) and a higher rate of postoperative arthrofibrosis ( P = .04). There was no difference in subsequent ACL injuries ( P = .41). Conclusion: Both groups demonstrated quality outcomes at a minimum 2-year follow-up. Patients with TEFs demonstrated lower mean clinical outcome scores compared with patients with ACL tears, but the differences were less than reported minimal clinically important difference values. Additionally, the TEF group experienced more postoperative anterior laxity and had a higher rate of postoperative arthrofibrosis. There was no difference in the rate of subsequent ACL injuries. The TEF group returned to sport sooner than the ACL group, but the postoperative activity levels were similar.

Background: Studies have shown good and excellent clinical and radiographic results after meniscal repair. Limited published information exists on the long-term outcomes, however, especially in a pediatric and adolescent population. Purpose: To determine long-term results of meniscal repair and concomitant anterior cruciate ligament (ACL) reconstruction in a pediatric and adolescent population. Specifically, the aims were to determine the clinical success rate of meniscal repair with concomitant ACL reconstruction, compare results with midterm outcomes, and analyze risk factors for failure. Study Design: Case series; Level of evidence, 4. Methods: Cases of meniscal repair with concomitant ACL reconstruction between 1990 and 2005 were reviewed among patients aged ≤18 years. Patient demographics, injury history, and surgical details were recorded, and risk factors for failure were analyzed. Physical examination findings and clinical outcomes at latest available follow-up were collected. Subjective knee outcomes were compared with midterm results. Descriptive statistics and univariate analysis were used to evaluate the available data. Results: Forty-seven patients (30 females, 17 males) with a mean age of 16 years (SD, 1.37) and a mean follow-up of 16.6 years (SD, 3.57) were included in this study. Overall, 13 patients (28%) failed meniscal repair and required repeat surgery at the time of final follow-up. Of the 13 failures, 9 underwent a subsequent meniscectomy; 2, meniscectomy and revision ACL reconstruction; 1, meniscal repair and revision ACL reconstruction; and 1, meniscal repair and subsequent meniscectomy. Mean International Knee Documentation Committee scores improved from 47.9 preoperatively to 87.7 postoperatively ( P < .01), and the mean score at long-term follow-up (87.7) did not significantly differ from that at the midterm follow-up (88.5) at a mean 7.4 years ( P = .97). Mean Tegner Activity Scale scores improved from 1.9 preoperatively to 6.3 postoperatively ( P < .01) and decreased from 8.3 at preinjury to 6.3 at final long-term follow-up ( P < .01). Conclusion: In conclusion, the long-term overall clinical success rate (failure-free survival) was 72% for repair of pediatric and adolescent meniscal tears in the setting of concomitant ACL reconstruction. Patients reported excellent knee subjective outcome scores that remained favorable when compared with midterm follow-up.

Purpose: To test the technical aspects and feasibility of seeding a combination of meniscus cells isolated from a rapid digestion protocol and mesenchymal stromal cells (MSCs) (20:80 ratio) into a meniscus scaffold for the development of a one-stage arthroscopic procedure for meniscus regeneration. Methods: A cadaveric study was performed using nine fresh frozen human cadaveric knee joints. Two different arthroscopic cell-seeding methods were applied to the Collagen Meniscus Implant (CMI ® ) as carrier scaffold: either (1) seeding before arthroscopic surgical implantation of the scaffold or (2) after implantation of the scaffold. The cells were injected inside the scaffold, using fast green-stained fibrin glue as carrier, to macroscopically visualize the amount of fibrin glue. Macroscopic pictures and confocal microscopy analyses were used to determine cell distribution and viability. In addition, the DNA content in the cell-seeded scaffold was determined. In addition, different concentrations of Liberase were examined to find the optimal concentration for rapid digestion of meniscus tissue. Results: Macroscopically, seeding before implantation showed a better distribution of fast green-stained fibrin glue carrier than seeding the scaffold before surgical implantation. In addition, it resulted in significantly more cells and a better cell distribution compared with seeding the scaffold after arthroscopic implantation. Both seeding methods did not affect cell viability. After rapid digestion, 0.0125% Liberase resulted in the highest cell isolation efficiency. Conclusions: This study demonstrates that living human meniscus cells can be isolated efficiently, combined with MSCs in 20:80 ratio, and uniformly delivered into a currently available meniscus scaffold. This scaffold can then be arthroscopically implanted, creating a one-stage solution for partial meniscal deficiency. Impact Statement Meniscus injury remains the most common indication for orthopedic surgery, but loss of functioning meniscus tissue is strongly correlated with development of early osteoarthritis. However, current clinical options for tissue engineering of the meniscus are limited. This study demonstrates the feasibility of combining human meniscus cells with mesenchymal stromal cells to enhance a meniscus scaffold for meniscus regeneration in a one-stage solution for partial meniscal deficiency.