Time Of Anterior Cruciate Ligament Reconstruction Research Articles

Femoral nerve block at time of ACL reconstruction causes lasting quadriceps strength deficits and may increase short-term risk of re-injury.

To determine whether femoral nerve blockade (FNB) at the time of primary ACL reconstruction is associated with meeting isokinetic extension strength return to sport criteria near completion of physical therapy and whether FNB affects 1-year or 2-year risk of ipsilateral ACL graft rupture or contralateral native ACL injury. Three-hundred and sixty patients (n = 244 with FNB, n = 116 no FNB) underwent primary ACL reconstruction. All patients completed rehabilitation and underwent functional strength testing towards the end of knee rehabilitation (mean 5.6months post-surgery). Association between FNB and isokinetic extension strength limb symmetry index (LSI) (goal LSI ≥ 90% for return to sport) as well as risk of recurrent ACL injury within first or second year after surgery was evaluated. Ipsilateral or contralateral ACL injury within 2years occurred in 11.2% of patients with FNB and 5.7% without FNB (p = 0.01). Patients with FNB had higher incidence of ipsilateral graft rupture within the first year after surgery but no difference in graft rupture during the second. Two-year risk of contralateral ACL injury was similar in both groups. At the time of initial testing, patients who received FNB had lower fast isokinetic extension LSI versus patients without FNB and were less likely achieve a goal ≥ 90% LSI; slow extension LSI was unaffected. Use of FNB at the time of primary ACL reconstruction can negatively affect achievement of isokinetic extension strength return to sport criteria. FNB increases risk of graft rupture within the first year after surgery but does not affect re-injury risk during the second. FNB may not be appropriate for use in patients already at high risk of ACL re-injury. III.

Lateral extra-articular tenodesis with ACL reconstruction demonstrates better patient-reported outcomes compared to ACL reconstruction alone at 2 years minimum follow-up

The role for extra-articular procedures in addition to ACL reconstruction to restore rotational stability is debated. We use lateral extra-articular tenodesis (LEAT) for patients that meet criteria. Our null hypothesis was that there would be no difference between two groups of patients that were treated with ACL reconstruction alone or ACL reconstruction with LEAT according to criteria. A prospectively collected database of patients that were treated primarily according to the presence of a high-grade pivot shift with LEAT at the time of ACL reconstruction was propensity-matched with a group of patients that underwent ACL reconstruction alone. Minimum follow-up was 2years. Stratified variable analysis of the groups was also performed. There were 218 and 55 patients in the ACL reconstruction group and ACL reconstruction with LEAT group, respectively. There were 125 patients and 46 patients after propensity matching with a median follow-up of 52months and 27months, respectively. Post-operative Lysholm score (P = 0.005), Tegner activity index (P = 0.003) and time to return to sport (P < 0.001) favoured ACL reconstruction with LEAT compared to ACL reconstruction alone. Sports with frequent change of direction maneuvers and higher rates of ACL injury (rugby, soccer, skiing) favoured ACL reconstruction with LEAT versus ACL reconstruction alone (P = 0.001). No significant difference in re-operation rate or type of surgery was found between the two surgical groups after propensity matching but 13 patients in the ACL reconstruction-only group re-injured their ACL, 8 of whom required supplementary LEAT at the time of revision surgery. Patient-reported outcomes and return to multi-directional sports after ACL reconstruction favour LEAT at the time of ACL reconstruction when narrow inclusion criteria are applied.

Hamstring Strength Recovery is Worse in Women than Men following ACL Reconstruction with Hamstring Autografts

Objectives: Graft choice in ACL reconstruction (ACLR) and post-operative rehabilitation may influence strength recovery and return to sports differently in men versus women. Persistent muscle weakness, impaired function, and poor patient reported outcomes are a concern for patients early after reconstruction and impact a timely and successful return to unrestricted physical activity without re-injury. However, little is known about the effect of graft choice and sex on short term ACLR recovery and return-to-play assessment. The purpose of this study was to compare knee extensor and flexor strength between male and female patients in isolated ACLR across both patellar tendon and hamstring autografts. Methods: A total of 166 patients with primary, unilateral and uncomplicated ACL reconstructions (22.6±9.9 years, 87 females, 5.94±.46 months post ACLR) were recruited for participation. There were 100 patients with bone patellar tendon bone (BPTB) autografts and 66 hamstring (HS) autografts. All patients completed the Tegner activity Scale and underwent bilateral isokinetic (90°/sec) tests of the knee extensor and flexor groups. Outcomes were recorded in a single session as part of a return-to-sport test battery. Strength was expressed as torque normalized to mass (Nm/kg) and limb-symmetry was expressed as a percentage of (involved/uninvolved)*100. Surgical Notes were obtained to determine the patient’s sex and type of autograft used at the time of ACLR. Strength measures were compared using 2x2 ANCOVAs (Sex by Graft Type) with the patient’s current activity level as a covariate. Post-hoc Cohen’s D effect sizes and 95% CI were calculated and statistical significance was defined as p-values of .05 or less. Results: There was a significant sex*graft type interaction for normalized knee flexor torque (P=.017) (Figure 1). Females with a HS graft (.592±.49 Nm/kg) had significantly less knee flexor torque compared to females with a BPTB graft (.910±.24 Nm/kg, Cohen’s d= .90[.45, 1.36]) and all males (HS: .937±.35, Cohen’s d=.87 [.45, 1.30]). There were significant main effects for graft type for knee flexor (P=.001) and extensor (P=.008) symmetry. Patients with a BPTB graft demonstrated less knee extensor symmetry (65.7±17%) and greater knee flexor symmetry (98.7±18%) compared to patients with a HS graft (Extension: 77.1±32%, Cohen’s d=.47[.16, .79]) (Flexion: 82.9±33%, Cohen’s d=.63[.31,.95]). We also observed a significant main effect for sex (P=.028) and graft type (P=.048) for normalized knee extensor strength. On average, males (1.67±.60 Nm/kg) demonstrated significantly greater normalized extensor torque than females (1.44±.75 Nm/kg, Cohen’s d= .34 [.03, .64]), and patients with a HS graft (1.66±.34 Nm/kg) demonstrated greater normalized extensor strength than those with a BPTB graft (1.45±.42 Nm/kg, Cohen’s d= .54 [.22, .85]). Conclusion: At approximately 6 months following ACLR, female patients reconstructed with hamstring autografts demonstrated weaker hamstring strength compared to females with a BPTB autograft. There were no differences in hamstring strength between graft types in males. Females appear to be recovering hamstring strength differently than males when using a hamstring autograft. These findings may have implications in surgical planning, post-operative rehabilitation and return to sports decision making. [Figure: see text]

Tibial insertion of the anterior cruciate ligament and anterior horn of the lateral meniscus share the lateral slope of the medial intercondylar ridge: A computed tomography study in a young, healthy population

BackgroundThe central intercondylar ridge (CIR) is an anatomical bony landmark that bisects the slope of the medial intercondylar ridge (MIR) between the tibial insertion of the anterior cruciate ligament (ACL) and anterior horn of lateral meniscus (AHLM) and was recently revealed by computed tomography (CT) evaluation corresponding to histologic slices of cadaveric knees. The purpose of this study was to clarify the shape and size of ACL and AHLM tibial insertion in young, healthy knees using the new bony landmark (CIR) and previously reported landmarks. MethodsThe contralateral healthy knees in 34 ACL-reconstructed patients (18 male patients, 16 female patients, mean age: 24.0 years) were scanned by CT. In the reconstructed coronal/sagittal images, bony landmarks of ACL (anterior: anterior ridge, posterior: blood vessel in tubercle fossa, medial: MIR, lateral: CIR) and AHLM (medial: CIR, lateral: bottom of the slope) were plotted for evaluation. The length of sagittal slices and the width in five coronal slices of the insertion were measured. ResultsThe ACL insertion consistently showed a boot-like-shape adjacent to the square shape of AHLM on three-dimensional imaging. The mean ACL sagittal length was 14.5 ± 1.9 mm, while the mean ACL widths (in mm) from anterior to posterior were 12.7 ± 2.7, 8.1 ± 1.9, 7.9 ± 2.0, 7.5 ± 1.5, and 7.2 ± 1.6, which was highly correlated with the tibial plateau size. ConclusionsThe boot-like-shape of the ACL tibial footprint insertion shared the slope of MIR with the rectangular shape of AHLM in young, healthy knees. This study may provide useful information for safe tibial tunnel creation at the time of ACL reconstruction.

Correlation Between Magnetic Resonance Imaging and Surgical Exploration of the Anterolateral Structures of the Acute Anterior Cruciate Ligament–Injured Knee

Background: Combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction is associated with improved clinical outcomes as compared with isolated intra-articular reconstruction, but the indications are not precisely defined. It may be the case that patients with proven anterolateral injury on preoperative imaging are most likely to benefit, but the accuracy of magnetic resonance imaging (MRI) is not known. Purpose/Hypothesis: To evaluate the correlation between MRI and surgical exploration in acute ACL-injured knees. The hypothesis was that a positive correlation would be identified between imaging and surgical findings for ALL/capsule and iliotibial band (ITB) injuries and that MRI would be highly sensitive, specific, and accurate. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Between January and May 2016, patients presenting with acute ACL injuries were considered for study eligibility. Included patients underwent 1.5-T MRI, which was evaluated by 3 investigators who attributed a Ferretti grade of injury to the anterolateral structures. At the time of ACL reconstruction, a lateral exploration was undertaken, and macroscopic injuries were identified. An evaluation of correlation between MRI and surgical exploration findings was performed. Results: Twenty-six patients participated in the study, and 96% had an ALL/capsule injury. The sensitivity, specificity, and accuracy of MRI and the correlation (K) with surgical exploration findings were as follows, respectively: any ALL/capsule abnormality—88%, 100%, 88.5%, and 0.47; differentiating partial or complete ALL/capsule tears—78.6%, 41.7%, 61.5%, and 0.23; ITB injuries—62.5%, 40%, 50%, and 0.27. The percentage agreement between MRI and surgical findings was 88% for ALL/capsule injury, 65% for ITB injury, and 53% for Ferretti grading. Conclusion: Surgical exploration demonstrates that injuries occur to the anterolateral structures in almost all acute ACL-injured knees. MRI is highly sensitive, specific, and accurate for detection of abnormalities of the ALL/capsule and shows a high percentage of agreement with surgical findings. MRI has low sensitivity, specificity, and accuracy for the diagnosis of ITB injury. The Ferretti grade could not be reliably established from MRI, and there was only fair agreement between MRI and surgical findings with respect to ITB abnormalities and determination of whether ALL/capsular tears were partial or complete.

Outcomes of Grade III Medial Collateral Ligament Injuries Treated Concurrently With Anterior Cruciate Ligament Reconstruction: A Multicenter Study

To evaluate differences in repair and nonoperatively managed grade III medial collateral ligament (MCL) injuries during anterior cruciate ligament (ACL) reconstruction. Patients enrolled in a multicenter prospective longitudinal group who underwent unilateral primary ACL reconstruction between 2002 and 2008 were evaluated. Patients with concomitant grade III MCL injuries treated either operatively or nonoperatively were identified. Concurrent injuries, subsequent surgeries, surgical chronicity, and MCL tear location were analyzed. Patient-reported outcomes were measured at time of ACL reconstruction and 2-year follow-up. Initially, 3,028 patients were identified to have undergone primary ACL reconstruction during the time frame; 2,586 patients completed 2-year follow-up (85%). Grade III MCL tears were documented in 1.1% (27 of 2,586): 16 operatively managed patients and 11 nonoperatively treated MCLs during ACL reconstruction. The baseline Knee Injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee scores were lower in patients who underwent operative MCL treatment. Reoperation rates for arthrofibrosis were 19% after repair and 9% after conservative management (P= .48). At 2years, both groups significantly improved; however, the nonoperative MCL group maintained superior patient-reported outcomes in terms of minimal clinically important differences, but these differences did not reach statistical significance (KOOS sports/recreation [88.2 vs 74.4, P= .10], KOOS knee-related quality of life [81.3 vs 68.4, P= .13], and International Knee Documentation Committee [87.6 vs 76.0, P= .14]). Tibial-sided MCL injuries were associated with clinically inferior baseline scores compared with femoral-sided MCL (KOOS knee-related quality of life, 34.4 vs 18.5, P= .09), but these differences resolved by 2years. Surgical chronicity did not influence 2-year outcome. Both operative and nonoperative management of MCL tears in our patient group demonstrated clinical improvements between study enrollment and 2-year follow-up. MCL surgery during ACL reconstruction was assigned to patients with worse symptoms at enrollment and was associated with worse outcomes at 2years. A subset of patients with severe combined ACL and medial knee injuries may benefit from operative management; however, that population has yet to be defined. Level III, retrospective cohort.

THE RATE OF MENISCUS TEARS IN ASSOCIATION WITH ANTERIOR CRUCIATE LIGAMENT INJURIES INCREASES WITH AGE

Background: Anterior cruciate ligament (ACL) tears are frequently associated with meniscal injury. Numerous authors have described associations between the presence of a meniscal tear at the time of ACL reconstruction and time to surgery and number of instability episodes1-3. The purpose of this study was to evaluate the relationship between age and the presence of a meniscal tear at the time of ACL reconstruction in children and adolescents. Methods: A single-institution retrospective review was performed of consecutive pediatric and adolescent patients who underwent ACL reconstruction over a 3.5-year period at a single institution. Inclusion criteria were age less than 20 years and an ACL injury treated with knee arthroscopy and ACL reconstruction. Patients with multiligament knee injuries were excluded. A chart review was performed to obtain demographic information and intra-operative findings. Meniscus tears were defined as tears documented during diagnostic arthroscopy. Results: Four hundred sixty-one patients met inclusion criteria, including 226 males (49%) and 235 females (51%) with a mean age of 15 years (range 7 – 20 years). The right and left knees were affected equally. Two hundred seventy patients (80%) had intra-operative evidence of a meniscal tear, including 215 lateral meniscus tears (56%) and 119 medial meniscus tears (44%). Sixty-four patients (14%) had both medial and lateral meniscus tears. Age at surgery was found to be a statistically significant independent predictor of the presence of a meniscus tear, odds ratio=1.14, 95% CI (1.05 – 1.25), p=0.003. For every 1-year increase in age, there is a 14% increase in the odds of having a meniscus tear and this is depicted in the figure below. Among patients 13 years of age and younger (n = 89), 47% had a meniscus tear. In contrast, 62% of patients 14 – 19 years of age (n = 301) had a meniscus tear, which was significantly greater (p = 0.01). Age was also a statistically significant independent predictor following subgroup analysis of medial and lateral meniscus tears. For every one year increase in age at surgery, there was a 21% increase in the odds of having a medial meniscus tear (odds ratio = 1.21, 95% CI: (1.08 – 1.35), p&lt;0.001) and a 13% increase in the odds of having a lateral meniscus tear (odds ratio = 1.13, 95% CI: (1.04 – 1.24), p=0.01. Conclusions: Among children and adolescents with anterior cruciate ligament tears, for every 1-year increase in age, there is a 14% increase in the odds of having a meniscus tear. Adolescents over the age of 13 years had a significantly greater rate of meniscus tears than did those 13 years of age and younger. A complete arthroscopic examination with close attention to the menisci is required to diagnose and treat meniscal tears. Surgeons should be comfortable with all meniscus repair techniques, including inside-out, outside-in, all-inside, radial, and transosseous root repairs as the majority of children and adolescent patients with ACL tears also have an associated meniscus tear. Anderson AF, Anderson CN. Correlation of meniscal and articular cartilage injuries in children and adolescents with timing of anterior cruciate ligament reconstruction. Am J Sports Med 2015;43(2):275-281. Millett PJ, Willis AA, Warren RF. Associated injuries in pediatric and adolescent anterior cruciate ligament tears: does a delay in treatment increase the risk of meniscal tear? Arthroscopy 2002;18(9):955-959. Shieh A, Bastrom T, Roocroft J, et al. Meniscus tear patterns in relation to skeletal immaturity: children versus adolescents. Am J Sports Med 2013;41(12):2779-2783.

OUTCOMES FOLLOWING ACL RECONSTRUCTION USING PATELLAR TENDON VERSUS HAMSTRING TENDON AUTOGRAFT IN ADOLESCENT ATHLETES: AN AGE-MATCH, SEX-MATCHED, AND BODY MASS INDEX-MATCHED COHORT STUDY

Background: Anterior cruciate ligament reconstruction (ACLR) remains one of the most commonly performed orthopaedic surgeries in adolescents and young adults. However, selection of the optimal graft for the individual patient remains controversial, considering multiple graft options, subtle technique differences, and wide-ranging bodies of evidence for each graft option in largely adult populations. However, multiple epidemiologic studies clearly demonstrate adolescents as the most greatly affected age-based sub-population, with the highest rates of re-tear and global morbidity, due to psychological and physical effects of long absences from athletic activity. Nevertheless, methodologically rigorous comparative studies specific to the adolescent athlete are largely absent from the literature. The purpose of the current study is to therefore investigate the outcomes of ACLR in adolescents receiving either patellar tendon/bone-tendon-bone (BTB) autograft (ACLR-BTB) or hamstring tendon autograft (ACLR-HS), using retrospective propensity score matching techniques to generate comparable cohorts. Methods: The study was designed as a retrospective chart review, with collection of cross-sectional data from a single pediatric tertiary care center over a thirteen year period (2003-2015). An initial cohort of patients, aged 13-19 years at time of primary ACLR-BTB or primary ACLR-HS by one of 5 surgeons, was identified through a comprehensive electronic medical record database query. Propensity score matching of ACLR-BTB and ACLR-HS subjects through a logistic regression model, with caliper restriction of 0.1 standard deviations, was then applied, based upon specific baseline characteristics that are frequently used by some surgeons to guide graft selection: age, sex, and body mass index (BMI). The resultant cohort of patients obtained a 1:2 (ACLR-BTB: ACLR-HS, 83 patients:186 patients) match. A chart review was performed to identify patient demographics, surgical data, and post-operative outcomes including graft rupture/re-tear and length of clinical follow-up. Patients were additionally contacted to obtain longer term sport participation and re-injury data that may have been investigated or addressed at outside institutions, as well as to obtain functional outcomes using region-specific questionnaires (Pedi-IKDC and HSS-Pedi FABS), which are validated for both this younger population and adult populations. Due to previous literature-based reports on greater anterior knee pain following ACLR-BTB, compared to ACL-HS, scores from the questions specific to knee pain or kneeling pain were extracted from the Pedi-IKDC results and analyzed to assess the potential influence of anterior knee pain on overall scores within this adolescent population. Results: At time of ACLR, the mean age and BMI of the matched ACLR-BTB patients were 17.1 years (sd: +/-1.14 years) and 25.8 (sd: +/-5.04), compared to 16.9 years (sd: +/- 1.38, p: 0.18) and 24.9 (sd: +/- 5.01, p: 0.18) for matched ACLR-HS patients, with similar male preponderance (ACLR-BTB: 77%, ACLR-HS: 72%, p: 0.47) and mean length of follow-up (ACLR-BTB: 42.9 months; ACLR-HS: 43.3 months). While mean Pedi-IKDC scores were slightly higher in the ACLR-BTB group (88.8; sd: +/-10.2, range: 56.5-100) than the ACLR-HS group (85.2; sd: +/- 16.1, range: 23.9-100), this difference was not statistically different (p: 0.50). When scores on questions regarding knee pain and kneeling difficulty were analyzed, no differences were seen between graft cohorts (ACLR-BTB: median knee pain score: 4, ACLR-HS: 4 p: 0.73; ACLR-BTB median kneeling difficulty score: 4, ACLR-HS: 4, p: 0.21). Activity level, based on the HSS-Pedi FABS score, was also similar (ACLR-BTB: 16, range: 3-29 vs. ACLR-HS: 17, range: 0-30; p: 0.96). Rates of ACL graft re-tear were not significantly different between groups, both when calculated based all possible follow-up methods (ACLR-BTB: 11%, ACLR-HS: 11%, p: 0.91), or when those patients responding to long-term follow up questionnaires were isolated (ACLR-BTB: 15%, ACLR-HS: 16%, p: 0.85). Conclusion/Significance: Despite previous studies, including large, multi-country registry-based analyses, demonstrating lower re-tear rates following ACLR-BTB than ACLR-HS, the current study, focused exclusively on adolescent cohorts matched for age, sex, and BMI, showed no difference in graft re-tear rates between the two cohorts at medium-term follow-up. Moreover, activity scores and functional knee outcome scores appear to be equivalent between these younger graft-based populations. In contrast to previous studies associating BTB autograft with greater long term anterior knee pain, adolescents appear to have equal degrees of knee pain or kneeling pain, regardless of graft choice, which may stem from greater healing and biologic remodeling capacity at graft harvest sites than adults or more modern techniques of patellar bone grafting and paratenon closure. Given the consistently high adolescent ACL re-tear rates in this and other studies, continued focus on ACL prevention programs and optimizing the timing and safety of return to play remains critical.

Consideration of lateral augmentation in anatomic anterior cruciate ligament reconstruction

Anatomic intra-articular anterior cruciate ligament reconstruction (ACLR) techniques have been shown to reliably correct anteroposterior (translational) stability; however, they have failed to restore normal tibial rotational kinematics. Re-establishing rotational stability correlates with return to sport, functional scores, overall knee function and patient satisfaction. Several structures in addition to the ACL have been identified as important contributors to rotational knee stability. Recent interest in the anatomical and biomechanical properties of the anterolateral soft tissue structures has led to a resurgence in surgical techniques, specifically anterolateral ligament (ALL) reconstruction and lateral extra-articular tenodesis (LET), to address rotational stability at the time of ACL reconstruction. In the accompanying review we outline the relevant anatomy, biomechanics and clinical results for lateral augmentation procedures; discuss the indications and describe our preferred LET technique for lateral augmentation.

Technique for partial transphyseal anterior cruciate ligament reconstruction in skeletally immature athletes: preliminary results

Background: A number of safe and successful surgical techniques to avoid physeal injury about the knee have been described, but their reported outcomes have not equaled success rates of procedures in skeletally mature patients. The purpose of this study was to determine the outcomes of an arthroscopic-assisted ACL reconstruction using a quadruple-looped hamstring graft with a synthetic graft extender and a physeal-sparing technique for partial transphyseal ACL reconstruction in skeletally immature patients. Methods: Medical record review identified skeletally immature patients who had this procedure and a minimum 6-month follow-up. A quadrupled-looped hamstring autograft and a synthetic graft extender allowed the optimal portion of the graft to be placed intra-articular and maintain sufficient length for proximal and distal fixation. Repeat physical examination included KT-1000 measurement, scanogram, and completion of a Lysholm knee scale and International Knee Documentation Committee (IKDC) evaluation. Results: Seventeen male patients 7.7 to 14.9 yr who fit the inclusion criteria were identified. All had open tibial and femoral physes at the time of ACL reconstruction. Average follow-up was 2 yr. At latest follow-up, all patients had stable Lachman tests and were able to return to sporting activities at their previous levels. Average limb-length discrepancy was 2.2 mm, with an average angular difference of 1.7 degrees, neither of which was statistically or clinically significant. Average Lysholm score was 91.5, and the average IKDC score was 92.7. Conclusions: This technique can restore motion and stability after ACL injury in skeletally immature patients while minimizing the risk of growth disturbance that might result in length or angular deformities. Level of Evidence: IV.

Relationship Between Time to ACL Reconstruction and Presence of Adverse Changes in the Knee at the Time of Reconstruction.

Background:Treatment of patients with anterior cruciate ligament (ACL) injuries is often complicated by secondary damage to the meniscus and cartilage.Purpose:To assess the association between time from ACL tear to ACL reconstruction (ACLR) and the presence of intra-articular injuries at the time of ACLR, including meniscal tears, irreparable meniscal tears, chondral damage, and knee compartment degenerative changes.Study Design:Cross-sectional study; Level of evidence, 3.Methods:Consecutive patients undergoing primary ACLR performed by a single surgeon in a Canadian health system over a 5.5-year period were included. Age at ACLR, activity level prior to injury, time from injury to ACLR (TFI), presence and degree of radiographic osteoarthritic features (International Knee Documentation Committee [IKDC] score by tibiofemoral and/or patellofemoral compartment), and surgeon-recorded meniscal lesions (presence and treatment [repair or excision]) and chondral lesions (International Cartilage Repair Society [ICRS] scale grade >2) at time of ACLR were extracted from medical records. The association between TFI (in quartiles: first quartile [0-36 wk] through fourth quartile [110-1000 wk]) and each outcome was assessed with multivariable logistic regression adjusted for age at ACLR and activity level.Results:A total of 860 individual patient records were included. The median patient age was 27.0 years (range, 12-63 years), 47.5% were female (403/849), and 47.2% were classified as playing competitive or professional sports versus recreational sport (337/714). After adjustment for age and activity level, TFI was associated with presence of medial meniscal tear (odds ratio [OR] of fourth-quartile vs first-quartile patients, 3.86; 95% CI, 2.38-6.24; P < .001), medial meniscal tear requiring greater than two-thirds meniscectomy (OR, 5.64; 95% CI, 2.99-10.67; P < .001), medial femoral condyle chondral damage (OR, 3.42; 95% CI, 1.96-5.95; P < .001), and medial tibiofemoral radiographic osteoarthritic features (OR, 22.03; 95% CI, 5.17-93.86; P < .001). TFI was not associated with adverse outcomes in the lateral tibiofemoral or patellofemoral compartments.Conclusion:Increases in TFI are associated with medial meniscal tears, including irreparable medial meniscal tears, medial femoral condyle chondral damage, and early medial tibiofemoral compartment degenerative changes at time of ACLR. These findings highlight the importance of establishing a timely diagnosis and implementing an appropriate treatment plan for patients with ACL injuries. This approach may prevent further instability episodes that place patients at risk of sustaining additional intra-articular injuries in the affected knee. Further research is required to understand the implications of TFI and to determine whether decreasing the TFI alters the natural history after an ACL injury.

Association of the Graft Size and Arthrofibrosis in Young Patients After Primary Anterior Cruciate Ligament Reconstruction.

This study investigated the association of graft-related surgical factors and patient characteristics with the odds of arthrofibrosis after primary anterior cruciate ligament reconstruction (ACL-R). A retrospective case-control study assessed consecutive patients who underwent primary ACL-R in one tertiary pediatric hospital. Each arthrofibrosis case was matched to three controls for sex, calendar year, and age at the time of ACL-R, as well as the primary surgeon. Conditional multivariable logistic regression assessed the independent association of graft diameter, time from injury to ACL-R, concomitant knee pathologies, and body mass index. Twenty arthrofibrosis cases of 1,121 ACL-R patients (incidence 1.8%) were matched to 60 controls resulting in the mean age of 14.5 years. An increase of 1 mm graft diameter was associated with 3.2-times increased odds of arthrofibrosis. Other variables were not independently associated with arthrofibrosis. For young patients, the decision on the graft size must consider the possibility of arthrofibrosis with a larger graft versus reinjury with a smaller graft.

The role of meniscal tears and meniscectomy in the mechanical stability of the anterior cruciate ligament deficient knee

BackgroundThe role of an intact meniscus in providing mechanical stability to the knee of anterior cruciate ligament (ACL) deficient and ACL reconstructed patients has not been well studied. MethodsThis was a prospective cohort study. A total of 205 patients undergoing ACL reconstruction were enrolled, of which 61 had normal menisci, 49 had a tear in the posterior horn of the medial meniscus (PHMM) (tear <40% of width = 19; >40% of width = 30), 35 had a tear in the lateral meniscus (<40% of width = 15; >40% = 20), 13 had a tear in the body and/or anterior horn of the medial meniscus (<40% of width = 6; >40% = 7) and 47 patients had a tear in both menisci. Patients with a tear in both menisci were excluded. The anterior translation of the tibia (ATT) was calculated preoperatively and postoperatively at three months and six months using KT-1000. Partial meniscectomy was performed in all unstable meniscal tears. ResultsThe mean age at the time of surgery was 25.2 ± 5.1 years. Patients with a normal meniscus showed side to side difference in KT-1000 of 4.8 ± 2.5 mm whereas those with a <40% tear and >40% tear in PHMM had a difference of 5.36 ± 3.07 mm (P = 0.46) and 7.08 ± 2.78 mm (P = 0.0002), respectively. Patients with a lateral meniscus <40% and >40% tear had a mean difference of 5.68 ± 2.96 mm (P = 0.22) and 5.95 ± 2.39 mm (P = 0.09), respectively. Patients with body and/or anterior horn of medial meniscus <40% and >40% had a difference of 5.41 ± 1.11 mm (P = 0.59) and 5.78 ± 2.38 mm (P = 0.35), respectively. At three months and six months KT-1000 differences of 2.3 ± 1.2 mm and 2.1 ± 1.2 mm were seen in patients with normal meniscus; 2.26 ± 1.51 mm and 2.16 ± 0.9 mm with partial meniscectomy of the PHMM <40%; 2.65 ± 1.53 mm and 2.4 ± 1.35 mm with partial meniscectomy of the PHMM >40%; 2.27 ± 1.19 mm and 2.07 ± 1.52 mm with partial meniscectomy of the lateral meniscus <40%; and 2.27 ± 1.44 mm and 2.07 ± 1.14 mm with partial meniscectomy of the lateral meniscus >40%; 2.55 ± 1.56 mm and 1.91 ± 1.09 mm with partial meniscectomy in body and/or anterior horn of medial meniscus <40% and 2.07 ± 1.81 and 2.14 ± 1.10 mm with partial meniscectomy in body and/or anterior horn of medial meniscus >40% (P > 0.05). ConclusionPHMM acts as a secondary stabilizer of the knee joint in the absence of functional ACL. There is no effect of partial meniscectomy on mechanical stability of the knee in ACL reconstructed patients. Medial or lateral partial meniscectomy performed at the time of ACL reconstruction does not affect the stability of ACL reconstructed knee. However, the presence of a concomitant tear in PHMM is associated with increased instability in ACL deficient knee.

There Are No Kinematic Differences Between Inframeniscal and Suprameniscal Anterolateral Ligament Injury in the Anterior Cruciate Ligament–Deficient Knee

Background: Previous research demonstrated that the attachment of the anterolateral ligament (ALL) to the lateral meniscus is stiffer and stronger in its tibial attachment than its femoral attachment. How this relates to anterolateral knee stability and lateral meniscal function is unknown. Hypothesis/Purpose: The hypothesis was that the ALL acts as a peripheral anchor to the lateral meniscus, aiding in anterolateral rotatory stability, and that the inframeniscal fibers of the ALL will provide greater anterolateral rotatory stability because of their greater tensile properties. The purpose was therefore to compare the difference in kinematics of the anterior cruciate ligament (ACL)–deficient knee between the infra- and suprameniscal ALL-sectioned states. Study Design: Controlled laboratory study. Methods: Eight paired fresh-frozen cadaveric knees were tested in a 5–degree of freedom loading jig under the following loading conditions: 5-N·m internal rotation at 15° incremental angles of flexion and combined 5-N·m internal rotation moment, 10-N·m valgus moment, and 88-N anterior translation force representing a pivot shift test at 0°, 15°, and 30° of flexion. The knees were tested under intact, ACL-deficient, and ACL-/ALL-deficient conditions, with the pairs of knees being randomized to either supra- or inframeniscal ALL sectioning. Resultant joint kinematics and tibiofemoral translations were measured and compared with a 2-way mixed repeated measures analysis of variance. Results: Internal rotation increased by 3° after sectioning of the ACL at 0° of knee flexion (P = .035). At 45° of knee flexion, internal rotation increased significantly by 2° between the ACL-deficient and the ACL-/ALL-deficient conditions (P = .049). Secondary kinematics of valgus and anterior translation were observed in response to the 5-N·m load after ACL and ALL sectioning. Analysis of the pivot shift showed increases in tibiofemoral translation after sectioning of the ACL, with further translations after sectioning of the ALL. No differences were observed between supra- and inframeniscal ALL sectioning under any of the loading conditions. Conclusion: An injury to the ALL, coexisting with ACL deficiency, results in only minor increases in knee joint patholaxity. No differences in pivot-shift kinematics or tibiofemoral rotations were observed between the supra- and inframeniscal sectioning of the ALL in the ACL-deficient knee Clinical Relevance: Tears of the midbody and/or posterior root attachment of the lateral meniscus are often observed at the time of ACL reconstruction. Increased anterolateral rotatory laxity has been observed in both lateral meniscus– and ALL-deficient states in combination with an ACL injury. While no significant functional relationship was found between the ALL and lateral meniscus, ALL sectioning did result in increased knee joint patholaxity, as demonstrated by composite tibiofemoral rotations.

Higher BMI predicts additional surgery at the time of ACL reconstruction.

Despite public recognition, obesity is a growing epidemic affecting an estimated 34% of adults and 20% of children in the U.S. As such, the number of ACL reconstructions performed in this population is likely to increase. The goal of this study is to evaluate the risk that increasing BMI poses for additional surgery at the time of ACL reconstruction. A retrospective analysis of the American College of Surgeons' National Surgical Quality Improvement Program's (ACS-NSQIP) database for the years 2005-2015 was conducted. Logistic regressions were used to assess the relationship between BMI and additional CPT codes for internal derangement at the time of ACL reconstruction. Internal derangement was defined as any CPT code for treatment of a meniscus tear, chondral lesion, or loose body removal. Surgeries for multi-ligamentous knee injuries were excluded. A total of 11,403 patients undergoing ACL reconstruction were identified. 41.9% of patients had an associated CPT code for internal derangement. As BMI increased, there was a corresponding increase in the odds of additional surgery. Specifically, for every 1.0 increase in BMI, the risk of additional surgery increased by 1.6% (p < 0.001). Compared to patients with a BMI of 18.5-24.9, those with a BMI 25-29.9 had an odds ratio (OR) of 1.112, BMI 30-34.9 had an OR of 1.137, BMI 35-39.9 had an OR of 1.249, and those ≥ 40 had an OR of 1.442 for additional surgery (p < 0.001). This nationally-representative, population-based study demonstrates that patients with elevated BMI are much more likely to require additional surgery in the setting of primary ACL reconstruction. This risk correlates with increasing BMI. Surgeons should keep these risks in mind when evaluating and counseling patients for surgery in the setting of ACL reconstruction. Case-control study, Level III.

Epidemiological Evaluation of Meniscal Ramp Lesions in 3214 Anterior Cruciate Ligament–Injured Knees From the SANTI Study Group Database: A Risk Factor Analysis and Study of Secondary Meniscectomy Rates Following 769 Ramp Repairs

Background: Ramp lesions are characterized by disruption of the peripheral meniscocapsular attachments of the posterior horn of the medial meniscus. Ramp repair performed at the time of anterior cruciate ligament reconstruction (ACLR) has been shown to improve knee biomechanics. Purpose: The primary objectives of this study were to evaluate the incidence of and risk factors for ramp lesions among a large series of patients undergoing ACLR. Secondary objectives were to determine the reoperation rate for failure of ramp repair, defined by subsequent reoperations for partial medial meniscectomy. Study Design: Case-control study; Level of evidence, 3. Case series; Level of evidence, 4. Methods: All patients underwent transnotch posteromedial compartment evaluation of the knee during ACLR. Ramp repair was performed if a lesion was detected. Potentially important risk factors were analyzed for their association with ramp lesions. A secondary analysis of all patients who underwent ramp repair and had a minimum follow-up of 2 years was undertaken to determine the secondary partial meniscectomy rate for failed ramp repair. Results: The overall incidence of ramp lesions in the study population was 23.9% (769 ramp lesions among 3214 patients). Multivariate analysis demonstrated that the presence of ramp lesions was significantly associated with the following risk factors: male sex, patients aged <30 years, revision ACLR, chronic injuries, preoperative side-to-side laxity >6 mm, and concomitant lateral meniscal tears. The secondary meniscectomy rate was 10.8% at a mean follow-up of 45.6 months (range, 24.2-66.2 months). Patients who underwent ACLR + anterolateral ligament reconstruction had a >2-fold reduction in the risk of reoperation for failure of ramp repair as compared with patients who underwent isolated ACLR (hazard ratio, 0.457; 95% CI, 0.226-0.864; P = .021). Conclusion: There is a high incidence of ramp lesions among patients undergoing ACLR. The identification of important risk factors for ramp lesions should help raise an appropriate index of suspicion and prompt posteromedial compartment evaluation. The overall secondary partial meniscectomy rate after ramp repair is 10.8%. Anterolateral ligament reconstruction appears to confer a protective effect on the ramp repair performed at the time of ACLR and results in a significant reduction in secondary meniscectomy rates.

Mesenchymal Stem Cells Isolated from the Anterior Cruciate Ligament: Characterization and Comparison of Cells from Young and Old Donors.

PurposeMesenchymal stem cells (MSCs) isolated from the anterior cruciate ligament (ACL) share multiple characteristics of bone marrow-derived mesenchymal stem cells (BMSCs), allowing their use for regenerative therapies. Injuries to the ACL can affect people of all ages. This study assesses whether the regenerative potential of ACL-derived MSCs (ACL-MSCs) from old donors is as high as the potential of ACL-MSCs from young donors.Materials and MethodsACL-MSCs were isolated from ACL tissues obtained from young and old donors at the time of ACL reconstruction or arthroplasty. Proliferative capacity, multilineage differentiation potential (chondrogenic, osteogenic, and adipogenic lineages), and transcriptome-wide gene expression were assessed and compared between young and old donors. BMSCs of middle-aged donors served as an additional comparator.ResultsNo substantial differences between ACL-MSCs from young and old donors were observed in their proliferative capacity and multilineage differentiation potential. The latter did not substantially differ between both ACL-MSC groups and BMSCs. Differential expression of genes related to the cytoskeleton and to protein dephosphorylation amongst other pathways was detected between ACL-MSCs from young and old donors.ConclusionsRegenerative potential of ACL-MSCs from old donors was not substantially lower than that from young donors, suggesting that regenerative therapies of ACL tears are feasible in both age groups. In vivo studies of the effect of age on the efficacy of such therapies are needed.

The Cost-Effectiveness of Meniscal Repair Versus Partial Meniscectomy in the Setting of Anterior Cruciate Ligament Reconstruction

To compare the cost-effectiveness of anterior cruciate ligament (ACL) reconstruction with meniscal repair to ACL reconstruction with partial meniscectomy. A decision-analytic Markov disease progression model with a 40-year horizon was created simulating outcomes after both meniscal repair and partial meniscectomy at the time of ACL reconstruction. Event probabilities, costs, and utilities were used for the index procedures. The development of osteoarthritis and subsequent knee replacement were either calculated or selected from published literature. Difference in cost, difference in quality-adjusted life-years (QALYs), and incremental cost-effective ratio were calculated to determine which index procedure is most cost-effective. There is total direct cost from ACL reconstruction with meniscus repair of $17,898 compared with that with partial meniscectomy of $24,768 (cost savings of $6,870). There was an estimated gainof 18.00 QALYs after ACL reconstruction with meniscus repair compared with 17.16 QALYs with partial meniscectomy (increase of 0.84 QALYs). In this scenario, meniscus repair is the dominant index procedure at the time of ACL reconstruction. Meniscal repair at the time of ACL reconstruction is more cost-effective than partial meniscectomy. Level IV, economic and decision analysis.

Ten-Year Risk Factors for Inferior Knee Injury and Osteoarthritis Outcome Score After Anterior Cruciate Ligament Reconstruction: A Study of 874 Patients From the Swedish National Knee Ligament Register

Background: Factors relating to the patient and anterior cruciate ligament (ACL) reconstruction may help to identify prognostic factors of long-term outcome after reconstruction. Purpose: To determine 10-year risk factors for inferior knee function after ACL reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: Prospectively collected data from the Swedish National Knee Ligament Register were extracted for patients who underwent ACL reconstruction between January 2005 and December 2006. Patients who had no data at the 10-year follow-up for the Knee injury and Osteoarthritis Outcome Score (KOOS) were excluded. Multivariable proportional odds regression modeling was used to assess 10-year patient- and surgery-related risk factors across all the KOOS subscales and the KOOS4 (mean score of 4 subscales: pain, knee-related symptoms, function in sport and recreation, and knee-related quality of life). Results: A total of 874 (41%) patients were included (male, 51.5%; median age at the time of ACL reconstruction, 27.5 years [range, 11.2-61.5 years]). An increase in the severity of concomitant articular cartilage injuries resulted in a reduced KOOS on 4 subscales (odds ratio, 0.64-0.80; P < .05). A higher preoperative KOOS pain score increased the odds of a higher score on the pain, symptoms, and sport subscales and the KOOS4. In addition, a higher preoperative body mass index was a significant risk factor for lower scores on 3 KOOS subscales and the KOOS4. No patient- or surgery-related predictor was significant across all KOOS subscales. Conclusion: This 10-year risk factor analysis identified several factors that can affect long-term knee function after ACL reconstruction. Most risk factors were related to preoperative patient-reported outcome and potentially modifiable. On the other hand, most of the surgery-related risk factors were nonmodifiable. Nevertheless, this information may be helpful to physicians and physical therapists counseling patients on their expectations of outcome after ACL reconstruction.

The anterolateral complex of the knee: results from the International ALC Consensus Group Meeting

The structure and function of the anterolateral complex (ALC) of the knee has created much controversy since the 're-discovery' of the anterolateral ligament (ALL) and its proposed role in aiding control of anterolateral rotatory laxity in the anterior cruciate ligament (ACL) injured knee. A group of surgeons and researchers prominent in the field gathered to produce consensus as to the anatomy and biomechanical properties of the ALC. The evidence for and against utilisation of ALC reconstruction was also discussed, generating a number of consensus statements by following a modified Delphi process. Key points include that the ALC consists of the superficial and deep aspects of the iliotibial tract with its Kaplan fibre attachments on the distal femur, along with the ALL, a capsular structure within the anterolateral capsule. A number of structures attach to the area of the Segond fracture including the capsule-osseous layer of the iliotibial band, the ALL and the anterior arm of the short head of biceps, and hence it is not clear which is responsible for this lesion. The ALC functions to provide anterolateral rotatory stability as a secondary stabiliser to the ACL. Whilst biomechanical studies have shown that these structures play an important role in controlling stability at the time of ACL reconstruction, the optimal surgical procedure has not yet been defined clinically. Concern remains that these procedures may cause constraint of motion, yet no clinical studies have demonstrated an increased risk of osteoarthritis development. Furthermore, clinical evidence is currently lacking to support clear indications for lateral extra-articular procedures as an augmentation to ACL reconstruction. The resulting statements and scientific rationale aim to inform readers on the most current thinking and identify areas of needed basic science and clinical research to help improve patient outcomes following ACL injury and subsequent reconstruction.Level of evidence V.