Contralateral Anterior Cruciate Ligament Research Articles

Association between passing return-to-sport testing and re-injury risk in patients after anterior cruciate ligament reconstruction surgery: a systematic review and meta-analysis.

Inconsistent results have been obtained regarding the association between return-to-sport (RTS) testing and the risk of subsequent re-injury following anterior cruciate ligament reconstruction (ACLR). We therefore conducted a systematic review and meta-analysis to assess the potential association between passing of RTS and the risk of re-injury for patients after ACLR. This meta-analysis was registered in INPLASY with the registration number INPLASY202360027. The electronic databases MedLine, EmBase, and the Cochrane library were systematically searched to identify eligible studies from their inception up to September 2023. The investigated outcomes included knee injury, secondary ACL, contralateral ACL injury, and graft rupture. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the random-effects model. A total number of nine studies involving 1410 individuals were selected for the final quantitative analysis. We noted that passing RTS test was not associated with the risk of subsequent knee injury (OR: 0.95; 95% CI: 0.28-3.21; P = 0.929), secondary ACL injury (OR: 0.98; 95% CI: 0.55-1.75; P = 0.945), and contralateral ACL injury (OR: 1.53; 95% CI: 0.63-3.71; P = 0.347). However, the risk of graft rupture was significantly reduced (OR: 0.49; 95% CI: 0.33-0.75; P = 0.001). This study found that passing RTS test was not associated with the risk of subsequent knee injury, secondary ACL injury, and contralateral ACL injury, while it was associated with a lower risk of graft rupture. Thus, it is recommended that patients after ACLR pass an RTS test in clinical settings.

Return to Sport, Re-injury and Performance After the Anterior Cruciate Ligament Reconstruction: Evaluating the Role of International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS) Scoring Systems.

Introduction Anterior cruciate ligament (ACL) tears are common injuries that can considerably impact an individual's quality of life and athletic performance. In these cases, surgical reconstruction of the ligament can be considered to restore stability to the knee. This study aims to investigate the time taken for individuals to return to sport post-ACL reconstruction, assess the rate of re-injuryand evaluate the reliability of the International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS) scoring systems in predicting a return to sport at the pre-injury level. Methods In this retrospective study, a total of 104 patients who underwent ACL reconstruction between January 2016 and December 2022 by one surgical team at Mater Dei Hospital, Malta were evaluated using a self-administered questionnaire. The questionnaire was based on different components including the sport practised at the time of injury, sport engagement classification, return to sport, the ability to return to pre-injury levels of performanceand re-injury. The participants then had to fill in IKDC and KOOS evaluation forms. Results In this study, 73% (n=76) of individuals successfully returned to sport after ACL reconstruction, with no significant difference being found between professional and recreational athletes (Chi-squared=0.00455, p=0.95). After reconstruction, 31.7% (n=33) of participants experienced an ipsilateral or contralateral ACL tear, with those returning to sport within six months showing a fivefold increase in re-injury risk compared to individuals who returned at eight or 12 months, suggesting a significant association between return duration and re-injury. The relationship between scoring systems and return to sport at the pre-injury level of performance was analysed using binary logistic regression, revealing that achieving scores of 85.6 or higher in IKDC or 89 or higher in KOOS meant having a 95% probability of returning to sport at the pre-injury level. Conclusions By considering these scoring systems with other post-operative criteria, clinicians can offer a more customised rehabilitation plan tailored to each patient who undergoes ACL reconstruction.

The Effect of Primary ACL Reconstruction on Career Longevity in English Premier League and Championship Soccer Players Compared With Uninjured Controls: A Matched Cohort Analysis

Background: Because of the multitude of variables that affect the retirement decisions of professional soccer players, it has proven difficult to isolate the effect of undergoing anterior cruciate ligament (ACL) reconstruction (ACLR) on career longevity. Purpose: To compare the career longevity of professional soccer players after a primary ACLR with that of an uninjured matched control cohort. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective review of a consecutive series of primary ACLR was performed between 2008 and 2018 in professional male soccer players from the senior author's practice. Each athlete with ACLR was matched to 3 control athletes who had not undergone ACLR according to age, league, playing position, and preinjury game appearances/minutes played. Player career statistics—including league, game appearances, and game minutes—were compiled for each year until retirement or July 1, 2022. Results: A total of 82 soccer players in the English Premier League or Championship at the time of their primary ACLR were matched to 246 control athletes. The mean career length after ACLR was 6 ± 2.6 years, while that of the matched control athletes was 7.6 ± 2.8 years (P < .001). After primary ACLR, an athlete had a 2 times greater chance of retirement compared with the matched control athlete (hazard ratio, 2.19; P < .001). At 5 years after ACLR, 16% of athletes had retired from professional soccer, while 8.5% of the matched cohort were retired (P = .060). By 10 years, 72% of the ACLR cohort had retired compared with 43% of the matched cohort (P < .001). Forwards were more likely to have shortened careers compared with goalkeepers (P = .021); however, no significant differences were observed between midfielders, defenders, and forwards. Within the ACLR cohort, a contralateral ACL tear during the athlete's career caused a 2.30 times (P = .022) increased chance of retirement compared with athletes with only 1 ACL tear during their career. Mechanism of injury, meniscal pathology, graft rerupture, and chondral lesions did not affect career length. Conclusion: Professional male soccer players who underwent ACLR had decreased career length by approximately 1.6 years compared with a matched player cohort.

A new neural network model that detects graft ruptures and contralateral anterior cruciate ligament injuries.

The purpose of this study was to develop a neural network model for predicting second anterior cruciate ligament (ACL) injury risk following ACL reconstruction using patient features from medical records. Of 486 consecutive patients who underwent primary unilateral ACL reconstruction, 386 patients (198 women, 188 men) with a mean age of 25.1 ± 11.6 years were included in this study. Fifty-eight features, including demographic data, surgical, preoperative and postoperative data, were retrospectively collected from medical records, and features with an incidence of less than 5% were excluded. Finally, 14 features were used for the analysis. The multilayer perceptron was composed of four hidden layers with a rectified linear unit as activation and was trained to maximise the area under the receiver-operating characteristic curve (auROC). Subsequently, validation was carried out through a rigorous threefold cross-validation process. To ascertain the most efficacious combination of features with the highest auROC, a single feature with the least impact on auROC maximisation was systematically eliminated from the comprehensive variable set, ultimately resulting in the retention of a mere two variables. The median follow-up period was 50.5 (24-142) months. Fifty-seven knees had a second ACL injury, with a graft rupture rate of 7.7%and a contralateral injury rate of 6.9%. The maximum auROC for predicting graft rupture was 0.81 with two features: young age and hamstring graft. Meanwhile, the maximum auROC for predicting contralateral ACL injury was 0.74 with seven features, including young age, presence of medial meniscus tear, small body mass index, hamstring graft, female sex and medial meniscus repairor treatment. A neural network model with patient features from medical records detected graft ruptures and contralateral ACL injuries with acceptable accuracy. This model can serve as a new, useful tool in clinical practice to inform decisions about ACL reconstruction and retuning to sports postoperatively. Level IV.

Primary All-Soft Tissue Quadriceps Tendon Autograft Anterior Cruciate Ligament Reconstruction With Suture Tape Augmentation Resulted in Satisfactory Patient Outcomes and a Low Graft Failure Rate in High School and Collegiate Athletes

To evaluate ≥2-year patient outcomes after primary all-soft tissue quadriceps tendon autograft (ASTQ) anterior cruciate ligament reconstruction (ACLR) with suture tape augmentation (STA) in skeletally mature high school and collegiate athletes. All high school and collegiate athletes who underwent primary ASTQ ACLR with STA with a minimum of 2-year follow-up were analyzed retrospectively. Patients were administered validated patient-reported outcome measures (PROMs) pre- and postoperatively. The minimal clinically important difference was calculated for each PROM based on this study population and applied to the individual patient. Return to sport, subsequent surgical intervention including contralateral ACLR, and KT-1000 arthrometer measurements for knee laxity were collected. Complications were assessed by physical examination, radiologic studies, or obtained via telephone. In total, 60 patients were included in the final data analysis, with a mean age of 16.8 years (95% confidence interval 13-23) and mean final follow-up of 37.1 months (95% confidence interval 33.1-41.1). Twelve patients (20%) required subsequent surgery on the ipsilateral knee, which included 7 patients having a subsequent meniscal procedure and 3 patients who underwent arthrolysis. None sustained a graft failure, and 6 patients sustained a contralateral ACL injury necessitating surgery. All PROMs improved at the final follow-up (P < .001). In addition, KT-1000 arthrometer measurements significantly improved postoperatively at 1-year clinical follow-up (P < .001). Most patients obtained the minimal clinically important difference thresholds for each PROM at the final follow-up. There were 48 patients (80%) who participated in pivoting sports. The return-to-sport rate at same level was 54 patients (90%), with 6 patients (10%) not returning to the same level because of graduation. ASTQ ACLR with STA in a young athletic patient population may result in a low graft failure rate while maintaining satisfactory patient outcomes at short-term follow-up, including a return to sport at the same level of 90%. Level IV, retrospective case series.

Global knee function rating more strongly influences adolescent athletes that sustain a sports-related surgical ACL re-injury or contralateral ACL injury.

This study evaluated differences between adolescent athletes who sustained a surgical anterior cruciate ligament (ACL) re-injury, or contralateral ACL injury following return to sports bridge programme participation (Group 1) compared to those that did not (Group 2). At 19.9 ± 7 years of age, 198 athletes participated in this study. Groups were compared for time postsurgery, preprogramme and postprogramme Knee Outcome Survey Sports Activity Scale (KOS-SAS) and global rating of knee function (GRKF) during sports activities, postprogramme lower extremity physical function test performance and perceived sports performance compared to preinjury level. By 6.0 ± 3.2 years postsurgery, 11 (5.6%) sustained another ACL injury. Group 1 was younger (17.3 ± 1.7 years vs. 20.1 ± 6.8 years, p < 0.001). Postprogramme re-evaluation revealed that Group 1 had a greater GRKF compared to their programme initiation GRKF than Group 2 (32.6 ± 38 vs. 20.0 ± 23, p = 0.04). Group 1 also had a greater mean preprogramme to postprogramme GRKF change than Group 2 (51.3 ± 31 vs. 35.5 ± 21, p = 0.02) (effect size = 0.73). More Group 1 subjects also had a GRKF difference that exceeded the overall mean than Group 2 (p = 0.04). Group 1 had moderately strong relationships between preprogramme and postprogramme GRKF score change and the postprogramme GRKF score (r = 0.65, p = 0.04) and between preprogramme and postprogramme KOS-SAS score change and postprogramme GRKF score (r = 0.60, p = 0.04). Global rating scores had a stronger influence among adolescent athletes that sustained either surgical ACL re-injury or contralateral ACL injury. Since group physical function and neuromuscular control factors were similar, clinicians need to increase their awareness and understanding of other factors that may influence surgical ACL re-injury or contralateral ACL injury risk. Level III, retrospective cohort study.

A Prospective Randomized Controlled Trial Investigating Quadriceps Versus Hamstring Tendon Autograft in Anterior Cruciate Ligament Reconstruction

Background: Numerous graft options are available when undertaking anterior cruciate ligament (ACL) reconstruction (ACLR), although a lack of high-quality evidence exists comparing quadriceps (QT) and hamstring (HT) autografts. Purpose: To investigate patient outcomes in patients undergoing HT versus QT ACLR. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: After recruitment and randomization, 112 patients (HT = 55; QT = 57) underwent ACLR. Patients were assessed pre- and postoperatively (6 weeks and 3, 6, 12, and 24 months), with a range of patient-reported outcome measures (PROMs), graft laxity (KT-1000 arthrometer; primary outcome variable), active knee flexion and extension range of motion (ROM), peak isokinetic knee extensor and flexor strength, and a 6-hop performance battery. Limb symmetry indices (LSIs) were calculated for strength and hop measures. Secondary procedures, ACL retears, and contralateral ACL tears were reported. Results: All PROMs and knee ROM measures significantly improved (P < .0001), and no other group differences (P > .05) were observed—apart from the Anterior Cruciate Ligament Return to Sport after Injury (ACL-RSI) score, which was significantly better in the HT group at 3 (P = .008), 6 (P = .010), and 12 (P = .014) months. No significant changes were observed in side-to-side laxity from 6 to 24 months (P = .105), and no group differences were observed (P = .487) at 6 (HT mean, 1.2; QT mean, 1.3), 12 (HT mean, 1.1; QT mean, 1.3), and 24 (HT mean, 1.1; QT mean, 1.2) months. While the HT group demonstrated significantly greater (P < .05) quadriceps strength LSIs at 6 and 12 months, the QT group showed significantly greater (P < .05) hamstring strength LSIs at 6, 12, and 24 months. The HT group showed significantly greater (P < .05) LSIs for the single horizontal (6 months), lateral (6 and 12 months), and medial (6 months) hop tests for distance. Up until 24 months, 1 patient (QT at 22 months) had a retear, with 2 contralateral ACL tears (QT at 19 months; HT at 23 months). Secondary procedures included 5 in the HT group (manipulation under anesthesia, notch debridement, meniscal repair, and knee arthroscopy for scar tissue) and 6 in the QT group (notch debridement, meniscal repair, knee arthroscopy for scar tissue, tibial tubercle transfer, and osteochondral autologous transplantation). Conclusion: Apart from the ACL-RSI, the 2 autograft groups compared well for PROMs, knee ROM, and laxity. However, greater hamstring strength LSIs were observed for the QT cohort, with greater quadriceps strength (and hop test) LSIs in the HT cohort. The longer-term review will continue to evaluate return to sports and later-stage reinjury between the 2 graft constructs. Registration: ACTRN12618001520224p (Australian New Zealand Clinical Trials Registry).

Reduction in re-rupture rates following implementation of return-to-sport testing after anterior cruciate ligament reconstruction in 313 patients with a mean follow-up of 50 months

Objectives:The objective of this study was to assess the mid-term effectiveness of a return to sport (RTS) test in relation to preventing anterior cruciate ligament (ACL) re-rupture and contralateral ACL injury following ACL reconstruction (ACLR). Furthermore, this study aimed to assess the timing of passing a, RTS-test after surgery, and the effect age has on RTS outcomes. Methods:Patients undergoing ACLR between August 2014 and December 2018 took an RTS-test following rehabilitation. The RTS-test consisted of the Anterior Cruciate Ligament Return to Sport After Injury Scale, a single-leg hop, a single-leg triple hop, a single-leg triple cross-over hop, a box-drop vertical jump down, a single-leg 4-rep max-incline leg press, and a modified agility T test. RTS-passing criteria were ≥90% limb symmetry index in addition to defined takeoff and landing parameters. Mid-term review assessed sporting level, ACL re-injury, and contralateral ACL injury. ResultsA total of 352 patients underwent RTS-testing, following ACLR with 313 (89%) contactable at follow-up, a mean of 50 months (standard deviation: 11.41, range: 28–76) after surgery. The re-rupture rate was 6.6% after passing the RTS-test and 10.3% following failure (p ​= ​0.24), representing a 36% reduction. Contralateral ACL injury rate after surgery was 6% and was 19% lower in those passing the RTS test. The mean age of patients passing their first RTS-test was significantly higher than that of those who failed (p ​= ​0.0027). Re-ruptures in those who passed the RTS test first time occurred late (>34 months), compared to those who failed first time, which all occurred early (<33 months) (p ​= ​0.0015). The mean age of re-rupture was significantly less than those who did not sustain a re-rupture (p ​= ​0.025). Conclusion:Passing a RTS-test following ACLR reduces ACL re-rupture by 36.21% and contralateral ACL injury by 19.15% at mid-term follow-up. Younger patients are more likely to fail a RTS-test and are at higher risk of contralateral ACL rupture.Level III Evidence.

An Isolated Midsubstance ACL Tear Repaired With the BEAR System

Background: Anterior cruciate ligament (ACL) repairs, once widely abandoned due to historically high failure rates, have recently regained interest with the development of the bridge-enhanced ACL repair (BEAR) implant, a novel arthroscopic technique that uses a resorbable protein-based implant combined with autologous blood to primarily repair a midsubstance ACL tear. This technical note presents a step-by-step surgical method for performing an isolated midsubstance ACL repair using the BEAR implant. Indications: The BEAR implant is indicated for skeletally mature patients at least 14 years of age with a complete rupture of the ACL, confirmed by magnetic resonance imaging. The complete ACL tear must have an attached stump to the tibia. Technique Description: A diagnostic arthroscopy is used to confirm complete rupture of the ACL and presence of residual tibial stump. A self-retrieving suture passage device is used to whipstitch a total of 6 passes with #2 Vicryl suture from distal to proximal through the residual stump. A notchplasty followed by femoral and tibial tunnels is created in a standard fashion. An Endobutton, soaked in a bacitracin solution, is then loaded with the sutures that were previously passed through the residual ACL stump and then through the femoral tunnel and cinched down to bone. The 4 suture ends that are coming from the Endobutton are then passed through the BEAR implant with the use of a Keith needle and shuttled through the tibial tunnel. The BEAR implant is hydrated with 15 cc of the patient's blood and is shuttled through the anteromedial portal with the knee in full extension. The 4 tibial sutures passed through the graft and tibial tunnel are passed, and tensioned to the proximal tibial with a second Endobutton. Standard closure and dressings are applied. Results: This new surgical implant and technique have shown noninferiority to ACL autograft reconstruction with respect to the International Knee Documentation Committee and anteroposterior laxity, with improved hamstring strength and decreased incidence of contralateral ACL tears at 2 years postoperative. Discussion/Conclusion: While initial data remain promising, future long-term designed studies are needed to determine the clinical efficacy of the BEAR technique, particularly comparing itself with bone-patellar tendon-bone autograft ACL reconstruction. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Risk Factors for Ipsilateral Versus Contralateral Reinjury After ACL Reconstruction in Athletes: A Systematic Review and Meta-analysis.

Anterior cruciate ligament (ACL) reinjury after ACL reconstruction (ACLR) can occur on the ipsilateral or contralateral side. Limited evidence exists regarding the difference between the incidence of reinjury to either knee, which is important in developing interventions to prevent ACL reinjury. To compare the reinjury rate of the ACL on the ipsilateral side versus the contralateral side in athletes after ACLR and investigate the risk factors that may cause different reinjury rates between the sides. Systematic review; Level of evidence, 4. A systematic review was performed based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies that involved ACL reinjury in athletes after ACLR were reviewed. Considering several risk factors, including age and sex, a comparison of ACL reinjury incidence on the ipsilateral and contralateral sides was performed using a meta-analysis. Of the 17 selected studies, 3 were found to be at high risk of bias, and thus, 14 (n = 3424 participants) studies were included in the meta-analysis. In this athletic population, the contralateral ACL had a significantly higher rupture rate than the ipsilateral graft (risk ratio [RR], 1.41; P < .0001). Female athletes were found to have a greater risk of ACL reinjury on the contralateral versus the ipsilateral side (RR, 1.65; P = .0005), but different results were found in male athletes. (RR, 0.81; P = .21). There was no statistical difference in the incidence rate of ACL reinjury to either side in adolescent athletes (RR, 1.15; P = .28). The contralateral ACL was more vulnerable to reinjury than the ipsilateral side in athletes after ACLR. Female athletes were more likely to reinjure their contralateral native ACL, while the same trend was not found in their male counterparts. The reinjury rate was comparable in both knees in adolescent athletes.

Ten-year outcomes of anterior cruciate ligament reconstruction with hamstring tendon autograft and femoral fixation with a cortico-cancellous screw suspension device

PurposeTo evaluate the clinical and radiographic outcomes of anterior cruciate (ACL) reconstruction at minimum 10-year follow-up.MethodsNinety-three patients who underwent primary unilateral ACL reconstruction with hamstring tendon autograft, transtibial technique and femoral cortico-cancellous screw suspension device (Athrax, Leader Medica s.r.l) between 2010 and 2012 were retrospectively reviewed. Mean follow-up was 136 months. Evaluation was performed using the International Knee Documentation Committee score (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm Knee Score and Tegner Activity Level Scale. Incidence of OA was determined by comparing standard anteroposterior and lateral weightbearing radiographs of the ACL-reconstructed and contralateral knee. Osteoarthritis severity was graded according to the Kellgren–Lawrence (KL) score.ResultsMedian Tegner activity level was 6 (5–7). Lysholm and IKDC scores were 100 (95–100) and 90 (86–95), respectively, KOOS was 98 (95–100). Of ACL-reconstructed knees, 41 (50%) had radiographic OA, of which 6 (7.3%) had severe OA (KL III). Of the contralateral healthy knees, 28 (34.1%) had radiographic evidence of OA. Of these 22 (26.8%) and 6 (7.3%) patients had, respectively, KL-I and KL-II. 11 patients (11.8%) underwent subsequent knee surgery: 5 (5.4%) revisions, 3 (3.2%) meniscal surgeries, 2 (2.2%) other surgeries, 1 (1.1%) contralateral ACL reconstruction.ConclusionsThe study demonstrates that ACL reconstruction with HT autograft and cortico-cancellous screw suspension device determines satisfying clinical results after 10 years of follow-up. From our cohort, a low rate of graft failure has been reported, even though almost 50% of patients present a knee OA greater or equal to grade II KL.

No Deficits in Functional Outcomes of the Contralateral Limb Are Seen When the Hamstring Is Harvested for Augmentation of Small Diameter Ipsilateral Hamstring Autograft

To evaluate clinical outcomes of the contralateral, nonoperative limb in patients undergoing contralateral hamstring (HS) autograft harvest compared with patients undergoing ipsilateral HS autograft harvest alone. This study included 96 patients who underwent isolated anterior cruciate ligament reconstruction (ACLR) using 4-stranded HS autograft (n= 85) or 4-stranded HS autograft augmented with contralateral HS (n= 13) due to inclusion of ipsilateral graft diameter <8 mm. Isokinetic flexion and extension strength and dynamic performance of the ipsilateral and contralateral limbs and limb symmetry index (LSI) were evaluated at 6 months' postoperatively. Rates of contralateral native ACL tear at minimum 2 years also were compared. For all comparisons, P < .05 was considered statistically significant. Normalized isokinetic knee flexion and extension strength of the contralateral limb did not differ between cohorts (P= .34; P= .21, respectively). LSI for knee extension peak torque and knee flexion peak torque did not differ between cohorts (P= .44; P= .67, respectively). No difference in LSI was seen for any dynamic performance testing (single leg hop, P= .97; triple leg hop, P= .14; 6-m timed hop, P= .99). No difference was observed in International Knee Documentation Committee (P= .99) or Knee Injury and Osteoarthritis Outcome Score subscale measures (P= .39-.86). No difference in rates of contralateral knee native ACL tears were seen between cohorts (HS autograft+ contralateral HS augmentation, n= 2, 15.4%; HS autograft, n= 7, 8.4%; P= .26). In this study, at the time of return to sport, we found no differences in contralateral limb functional performance or limb symmetry measurements between patients undergoing contralateral HS autograft harvest for augmentation of smaller (<8 mm) diameter HS autografts harvested from the injured extremity. Level III, retrospective cohort study.

Anterior Cruciate Ligament Tears in the Adolescent Population: Injury Demographics and Risk of Reinjury Among High School Athletes.

The incidence of anterior cruciate ligament (ACL) injuries is increasing among the adolescent population with a peak occurring in the high school age range. To characterize recent epidemiologic trends of ACL injuries, ACL reconstruction (ACLR), and retear rates in high school adolescents based on age, participating sport, and mechanism of injury. Retrospective case series. A prospectively maintained institutional database was retrospectively reviewed for all patients 18 or younger who underwent primary ACLR between 2015 and 2020. Odds ratios were calculated for baseline patient characteristics and their association with risk of retear. Multivariate regression analysis was also performed to identify the relationship between retear and specific categorical variables. A total of 482 patients were included, with a mean follow-up time of 13.0 ± 11.8 months. Patients were an average age of 16.1 ± 1.3 years old (range: 13 to 18 y). Initial presentation of ACL injuries in high school athletes often occurred at 16 years old regardless of the sport played. Based on age, high school freshmen and seniors are found to have an increased risk of ACL retear. One hundred three patients (21.6%) completed at least 2 or more years of follow-up after ACLR. Of these patients, 38.8% received a bone-tendon-bone (BTB) autograft, 36.9% hamstring autograft, 14.6% quadriceps tendon autograft, and 3.9% received hamstring allograft or other graft (eg, tibialis anterior and BTB allograft), respectively. There were 25 ipsilateral ACL retears that occurred in the patient cohort (5.2%). Thirteen (52%) of retears were females. Football and soccer were the most common sports played by patients with a retear of the ipsilateral knee (31.8% and 27.3%, respectively). Patients who were 13 to 14 or 18 years old ( P = 0.009 and 0.035, respectively) or who received a tibialis anterior/BTB allograft ( P = 0.002) were found to have increased risk of ACL retear compared with other age groups. When evaluating by sex, female soccer players had a greater risk of retear compared with male soccer players ( P = 0.007). When adjusting for multiple variables, (including age, sex, body mass index, primary reconstruction graft choice, sport, and length of follow-up), the odds of ipsilateral retear in patients who received hamstring autograft ( P = 0.02), sustained a contralateral ACL tear ( P = 0 .04), or a contact injury ( P = 0.01) were increased. Initial presentation of ACL injuries in high school athletes often occurs at 16 years old regardless of the sport played. Based on age, high school freshmen and seniors are found to have an increased risk of ACL retear. However, the overall rate of ACL retear in high school athletes of all ages is low. Patients who underwent ACLR with hamstring tendon autograft had a greater risk of retear compared with other graft types. Female soccer players also had a greater risk of ACL retear. High school athletes must take caution when in the early high school years (underclassman) and more senior years (upperclassman), as susceptibility for ACL retears is elevated. Level IV.

ACL Reconstruction With Quadriceps Soft Tissue Autograft Versus Bone-Patellar Tendon-Bone Autograft in Cutting and Pivoting Athletes: Outcomes at Minimum 2-Year Follow-up.

The optimal graft choice for anterior cruciate ligament (ACL) reconstruction (ACLR) in the high-level cutting and pivoting athlete remains controversial. Studies have shown similar outcomes when directly comparing bone-patellar tendon-bone (BPTB) autograft versus quadriceps soft tissue (QST) autograft in the general population. However, no studies have directly compared these 2 grafts in athletes participating in cutting and pivoting sports. It was hypothesized that, compared with BPTB autograft, the QST autograft would result in similar patient-reported outcomes and rates of retear, return to sport, and complications. Cohort study; Level of evidence, 3. A retrospective review was performed on athletes participating in cutting and pivoting sports (soccer, American football, lacrosse, and basketball) who underwent primary ACLR with either BPTB autograft or QST autograft chosen by the athlete between January 2015 and January 2019. The International Knee Documentation Committee (IKDC) subjective knee evaluation and Lysholm Knee Scoring Scale were used to evaluate patient-reported outcomes. Return-to-sport and complication rates were identified. Descriptive statistics were expressed using Mann-Whitney test or Student t test for continuous variables and the chi-square test for categorical variables. A total of 68 athletes (32 QST, 36 BPTB) were included for analysis. The percentage follow-up was 89% (32/36) for the QST autograft group and 86% (36/42) for the BPTB autograft group. The 2-year IKDC score (QST, 90.5 ± 6.6 vs BPTB, 89.7 ± 7.8) and 2-year Lysholm score (QST, 91.3 ± 7.5 vs BPTB, 90.5 ± 8.6) were similar between groups. The percentage of athletes able to return to sport within the follow-up period was also similar (88% vs 83%; P = .63). There were 2 retears requiring revision in the BPTB group (6%) and no retears in the QST group (P = .18). One contralateral ACL rupture occurred in the QST group (3%) and 4 in the BPTB group (11%) (P = .21). The QST and BPTB autografts demonstrated similar patient-reported outcomes, return-to-sport rates, and complication rates after primary ACLR at 2-year follow-up. Both autografts appear to be reliable and consistent options for ACLR in the cutting and pivoting athlete.

Lateral Extra-Articular Tenodesis in Skeletally Immature Patients: The Modified Ellison Technique

Background: Anterior cruciate ligament (ACL) rupture is an increasingly common injury in the young population. Unfortunately, reinjury rates in this population following ACL reconstruction (ACLR) are also very high. As such, lateral extra-articular procedures have been proposed to augment ACLR and shown to reduce reinjury rates. Most techniques use a strip of iliotibial band (ITB) fixed proximally on the distal femur in close proximity to the lateral femoral epicondyle, which in the skeletally immature patient may be closely associated with the distal femoral physis. In addition, there is also a risk of convergence with the femoral tunnel for the ACLR. The modified Ellison technique avoids both of these risks given it is a distally based tenodesis with its fixation point on the proximal tibial epiphysis. The purpose of this video is to describe a modified Ellison technique in a skeletally immature patient. Indications: Primary ACLR in skeletally immature patients at high risk of ACL graft rerupture due to their young age, a positive family history of ACL rupture in a first-degree relative, previous contra-lateral ACL rupture, generalized joint hypermobility, high-grade pivot-shift test, and participating in pivoting sports. Technique Description: The modified Ellison technique is a distally based lateral extra-articular procedure. A 1-cm strip of ITB is detached from Gerdy’s tubercle, passed beneath the lateral collateral ligament, and reattached back to from where it was removed. The fixation is within the proximal epiphysis of the tibia. Results: In a high-risk adult population, the modified Ellison technique has been shown to have a low ACL graft reinjury rate at 2 years following an ACLR. Biomechanical studies have demonstrated that a modified Ellison technique closely restores native knee kinematics following simulated anterolateral complex injury. Discussion/Conclusion: The modified Ellison technique is a safe and reproducible lateral extra-articular procedure in skeletally immature patients when performed in combination with an ACLR. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Comparison of ACL and Anterolateral Ligament Reconstruction With Isolated ACL Reconstruction Using Hamstring Autograft: Outcomes in Young Female Patients With High-Grade Pivot Shift.

Inferior return to sports (RTS) and functional outcomes have been reported in women after anterior cruciate ligament reconstruction (ACLR). The purpose was to evaluate the results of combined ACLR and anterolateral ligament reconstruction (ALLR) in young women with a high-grade pivot shift (grade ≥2). It was hypothesized that combined ACLR and ALLR would result in better RTS and rotational stability than isolated ACLR. Cohort study; Level of evidence, 3. Two groups were retrospectively evaluated and compared. Group I (n = 39; mean age, 31.1 ± 5.7 years) underwent isolated ACLR using hamstring autografts; group C (n = 39; mean age, 30.4 ± 6.1 years) underwent combined ACLR and ALLR. Subjective outcome measures included the International Knee Documentation Committee subjective form, Lysholm, Tegner, and ACL-Return to Sport after Injury (ACL-RSI). Objective tests included a KT-2000 arthrometer stress test, a pivot-shift test, an isokinetic strength test, a Y-balance test, and a single-leg hop test. A postoperative questionnaire was administered to determine the rates and types of RTS, quality of sports performance, and reinjury and satisfaction rates. Subjective scores and clinical tests were performed at 2 years. Magnetic resonance imaging and second-look arthroscopy were conducted during the 1- and 2-year follow-ups, respectively. The mean follow-up for groups I and C were 30.4 ± 3.9 and 29.3 ± 3.5 months, respectively (P = .194). Patients in group C had better anteroposterior (P = .001) and rotational (P = .005) stability and higher ACL-RSI scores (P = .025) than those in group I. Group C had higher composite and posteromedial reach scores on the Y-balance test than group I (P = .014 and P = .010, respectively). A total of 26 (66.7%) patients in group C and 17 (43.6%) in group I returned to their prior level of sports (P = .040). Rerupture of the ACL graft and contralateral ACL rupture occurred in 2 (5.1%) and 2 (5.1%) patients in group I, respectively, compared with no rerupture or contralateral ACL rupture in group C. Combined ACLR and ALLR in young women with a high-grade pivot shift was associated with better knee stability parameters, dynamic postural stability, and psychological readiness to RTS than isolated ACLR.

What it takes to have a high-grade pivot shift-focus on bony morphology.

Variations in femoral and tibial bony morphology have been associated with higher clinical grading and increased quantitative tibial translation, but not tibial acceleration, during the pivot shift test following anterior cruciate ligament (ACL) injury. The purpose of this study was to determine the impact of femoral and tibial bony morphology, including a measurement influenced by both parameters (the Lateral Tibiofemoral Articular Distance (LTAD)), on the degree of quantitative tibial acceleration during the pivot shift test and rates of future ACL injury. All patients who underwent primary ACL reconstruction from 2014 to 2019 by a senior orthopedic surgeon with available quantitative tibial acceleration data were retrospectively reviewed. All patients underwent a pivot shift examination under anesthesia with a triaxial accelerometer. Measurements of femoral and tibial bony morphology were performed by two fellowship-trained orthopedic surgeons using preoperative magnetic resonance imaging and lateral radiographs. Fifty-one patients were included at a mean follow-up of 4.4years. The mean quantitative tibial acceleration during the pivot shift was 13.8m/s2 (range: 4.9-52.0m/s2). A larger Posterior Condylar Offset Ratio (r = 0.30, p = 0.045), smaller medial-to-lateral width of the medial tibial plateau (r = -0.29, p = 0.041), lateral tibial plateau (r = -0.28, p = 0.042), and lateral femoral condyle (r = -0.29, p = 0.037), and a decreased LTAD (r = -0.53, p < 0.001) significantly correlated with increased tibial acceleration during the pivot shift. Linear regression analysis demonstrated an increase in tibial acceleration of 1.24m/s2 for every 1mm decrease in LTAD. Nine patients (17.6%) sustained ipsilateral graft rupture and 10 patients (19.6%) sustained contralateral ACL rupture. No morphologic measurements were associated with rates of future ACL injury. Increased convexity and smaller bony morphology of the lateral femur and tibia were significantly associated with increased tibial acceleration during the pivot shift. Additionally, a measurement, termed the LTAD, was found to have the strongest association with increased tibial acceleration. Based on the results of this study, surgeons can utilize these measurements to preoperatively identify patients at risk of increased rotatory knee instability. Level IV.

Poster 313: More Severe Adverse Events are Associated with Worse Patient Reported Outcome Measures following Anterior Cruciate Ligament Reconstruction with and without Lateral Extra- articular Tenodesis Augmentation – Results from the Stability Randomized Trial

Objectives: Investigate how the severity of adverse events encountered during the follow up period of the Stability Study were associated with patient reported outcomes at two years post-operative. Methods: Stability is a pragmatic, multicenter, randomized clinical trial comparing single-bundle hamstring tendon ACLR with combined ACLR + LET. Patients aged 14-25 years with an ACL deficient knee were included (n = 618). Participants completed PROMs (KOOS, IKDC, ACL-QOL), and adverse events were documented pre-operatively and at 3, 6, 12 and 24 months postoperatively. Adverse events were categorized into four groups: none (no adverse event), minor medical (resolved spontaneously or with minimum medical management), minor surgical (event such as meniscus tear or stiffness that required surgical intervention but is not a graft rupture), contralateral ACL rupture, and graft rupture. A generalized linear model was used to compare mean PROM scores with the different levels of adverse events. Results: The rate of minor medical adverse events (11.2%), minor surgical adverse events (7.4%), and ipsilateral (7%) or contralateral (3%) ACL tears at 24 months post-operative were low considering the high-risk patient profile. There was no difference in the proportion of minor medical events, minor surgical events, or contralateral ACL ruptures between the ACLR only and ACLR + LET groups (p&gt;0.05). The ACLR only group had a significantly higher rate of graft rupture (11 vs 4%, p&lt;0.01). Increasing severity of adverse events were associated with lower PROM scores at 24 months post-operative. Patients who experienced any adverse event within the two-year follow up had significantly lower outcome scores than those with no events. When only adverse events in the first year post-operative were included, the influence of minor medical and minor surgical events was largely washed out suggesting the effect on outcomes may be due to recency rather than severity. However, graft tears and contralateral ACL tears within the first year led to significantly lower scores at two-years post-operative in all outcomes (p&lt;0.01). Conclusions: Increasing severity of adverse events were associated with lower patient reported outcome measures at 2 years post-operative. Recent minor medical and minor surgical events worsened PROM scores, but this effect was largely eliminated within a year of the event. Patients who experience a graft rupture or contralateral ACL tear appear to have a significantly lower PROMs at 2 years post- operative, regardless of the time at which the tear occurs. Therefore, the benefit of the LET procedure reducing graft rupture outweighs the potential for less severe events such as hardware irritation/removal which will likely be less detrimental to patient-important outcomes.

Paper 39: A Survival Analysis of ACL Graft and Contralateral ACL Ruptures in Patients Under 18 Years

Objectives: Although high rates of graft and contralateral anterior cruciate ligament (ACL) ruptures have been reported in younger patients after ACL reconstruction, recent evidence suggests that previously reported crude event rates underestimate the actual event risk. Therefore, the aim of this study was to report rates of graft and contralateral ACL rupture after ACL reconstruction in a large series of younger patients using survival analysis. Methods: A consecutive series of 400 patients who were under 18 years at the time of primary ACL reconstruction were identified from a single surgeon database over a 12-year period ending January 2018. Patients with a prior contralateral ACL rupture (n=8) or bilateral ACL ruptures (n=2) were excluded as were two patients who died within 6 months of surgery, leaving 388 (203M, 185F) in the final dataset. Bespoke survey data and clinic follow-up data were used to record graft rupture and contralateral ACL rupture events. Rates of graft and contralateral ACL rupture were calculated with Kaplan-Meier survival analysis. Log rank tests were used to compare survival functions between males and females. Results: The cumulative rates of graft rupture via survival analysis were 11% at 2 years, 16% at 4 years and 28% at 8 years. For contralateral ACL injury the cumulative rates were 7% at 2 years, 17% at 4 years and 49% at 8 years. Males had significantly greater rates of graft rupture than females although this was more prominent at 4 years (22% vs 9%) than at 8 years (31% vs 23%) after surgery (figure 1). Contralateral ACL rupture survival functions were not significantly different between male and female patients, although rates were higher in females until 5 years after which males had a notable increase in contralateral ACL ruptures with a cumulate rate of 63% at 8 years compared to 35% for females (figure2). Conclusions: The current study is one of the largest consecutive series of younger patients with one of the longest follow-up periods that reports a high risk for a second ACL injury. Over time, the cumulative risk for contralateral ACL rupture was higher than for graft rupture. This contradicts previous work that had shorter follow-up times. In males, the risk for contralateral ACL rupture substantially increased after 5 years. Understanding the postoperative time course for second ACL injury in young patients is important so that factors which contribute to this increased risk can be better understood and such injuries prevented.

Poster 325: Untreated Ruptures of the Anterior Cruciate Ligament: a 54 Year Follow-Up Study

Poster 325: Untreated Ruptures of the Anterior Cruciate Ligament: a 54 Year Follow-Up Study