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OBJECTIVE: To compare the time to return to sport (RTS) between patients who did and did not suffer a second anterior cruciate ligament (ACL) injury after ACL reconstruction. DESIGN: Etiology systematic review with meta-analysis. LITERATURE SEARCH: Cochrane Library, Embase, Medline, AMED, and PEDro databases were searched in August 2021 and again in November 2022. STUDY SELECTION CRITERIA: Clinical studies reporting time to RTS after ACL reconstruction and second ACL injury were eligible. DATA SYNTHESIS: We pooled continuous data (time [months] and proportions [%]), with random-effects meta-analyses. Pooled estimates were summarized in forest plots. A qualitative data synthesis was also performed. RESULTS: Twenty-one studies were included in the meta-analysis and 33 in the qualitative synthesis. Pooled incidence of second ACL injury was 16.9% (95% confidence interval [CI]: 12.8, 21.6). Patients who suffered a second ACL injury returned to sport significantly earlier (25 days; 95% CI: 9.5, 40.4) than those who did not suffer another injury. There was no difference in time to RTS for professional athletes who suffered a second ACL injury and those who did not. The certainty of evidence was very low. CONCLUSION: There was very low-certainty evidence that patients who suffered a second ACL injury had returned to sport 25 days earlier than patients who did not have another injury. For professional athletes, there was no difference in time to RTS between athletes who suffered a second ACL injury and athletes who did not. J Orthop Sports Phys Ther 2024;54(3):1-15. Epub 30 November 2023. doi:10.2519/jospt.2023.11977 .

Purpose: Anterior cruciate ligament tears and anterior cruciate ligament reconstruction (ACLR) are common in young athletes. The modifiable and non-modifiable factors contributing to ACLR failure and reoperation are incompletely understood. The purpose of this study was to determine ACLR failure rates in a physically high-demand population and identify the patient-specific risk factors, including prolonged time between diagnosis and surgical correction, that portend failure., Methods: A consecutive series of military service members with ACLR with and without concomitant procedures (meniscus [M] and/or cartilage [C]) done at military facilities between 2008 and 2011 was completed via the Military Health System Data Repository. This was a consecutive series of patients without a history of knee surgery for two years prior to the primary ACLR. Kaplan-Meier survival curves were estimated and evaluated with Wilcoxon test. Cox proportional hazard models calculated hazard ratios (HR) with 95% confidence intervals (95% CI) to identify demographic and surgical factors that influenced ACLR failure., Results: Of the 2735 primary ACLRs included in the study, 484/2,735 (18%) experienced ACLR failure within four years, including (261/2,735) (10%) undergoing revision ACLR and (224/2,735) (8%) due to medical separation. The factors that increased failure include Army Service (HR 2.19, 95% CI 1.67, 2.87), > 180 days from injury to ACLR (HR 1.550, 95% CI 1.157, 2.076), tobacco use (HR 1.429 95% CI 1.174, 1.738), and younger patient age (HR 1.024, 95% CI 1.004, 1.044)., Conclusion: The overall clinical failure rate of service members with ACLR is 17.7% with minimum four-year follow-up, where more patients are likely to fail due to revision surgery than medical separation. The cumulative probability of survival at 4 years was 78.5%. Smoking cessation and treating ACLR patients promptly are modifiable risk factors impacting either graft failure or medical separation., Level of Evidence: Level III., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Purpose: This study aimed to systematically evaluate the clinical, functional, and radiological outcomes, complications, and rate of return to sports among patients with RAMP lesion of the medial meniscus encountered during anterior cruciate ligament (ACL) reconstruction., Methods: A systematic review was conducted based on the PRISMA guidelines. Two independent reviewers searched the PubMed, Scopus, Embase, and Cochrane Library databases using the terms "ACL" or "anterior cruciate ligament," and "RAMP lesion." The outcome measures extracted from the studies were the Short Form-12 (SF-12) in its mental and physical component (MCS and PCS), Lysholm score, Subjective IKDC, Marx Score, WOMAC Score, Tegner, Radiological changes, complications, failures and/or revision surgery, and rate of return to sports., Results: The cohort of patients consisted of 1,243 participants with a mean age of 28.6 ± 2.6. The mean postoperative follow-up was 40.9 ± 6.3 months. A total of 1145 (92.1%) RAMP lesions were repaired with concomitant ACL reconstruction, while only 98 (7.9%) lesions were left untreated (or treated with abrasion only). The Lysholm score was used in 6 studies (in one only at final follow-up), with a significant improvement in all the studies (Lysholm pre 60.03 ± 6.12; Lysholm post 89.9 ± 5.0). Eight studies out of nine reported Subjective IKDC score, and a significant improvement was noted in all cases (IKDC pre 56.2 ± 5.8. IKDC post 84.9 ± 3.7). Of 18 (1.4%) complications reported, 15 (1.2%) were related to RAMP/ACL surgery, and of the remaining three (0.2%) two (0.2%) were hematomas and one (0.1%) a contralateral ACL lesion. Of the 106 (8.5%) revision surgeries required, 5 (0.4%) were in non-treated lesions [two (0.2%) ACL re-ruptures and three (0.2%) medial meniscus re-injury]. In treated patients, the revision occurred for the following reasons: 75 (6.0%) meniscectomy, 14 (1.1%) meniscal suture revisions, 11 (0.9%) ACL failures and one (0.1%) arthrolysis., Conclusions: It is not yet clear if, in all cases of ACL reconstruction in which a medial meniscal RAMP lesion is encountered, the lesion needs to undergo surgical repair. Accordingly, it is recommended that in the repair of all unstable medial meniscal RAMP lesions during an ACL reconstruction in cases associated with a stable RAMP lesion, the surgeon may decide on repair based on the patient profile., Level of Evidence: Level IV., (© 2022. The Author(s).)

Introduction: Many factors can affect the return to pivoting sports, after an Anterior Cruciate Ligament Reconstruction. Prehabilitation, rehabilitation, surgical and psychological aspects play an essential role in the decision to return to sports. The purpose of this study is to reach an international consensus about the best conditions for returning to sports in soccer-one of the most demanding level I pivoting sports after anterior cruciate ligament (ACL) reconstruction., Methods: 34 International experts in the management of ACL injuries, representing all the Continents were convened and participated in a process based on the Delphi method to achieve a consensus. 37 statements related to ACL reconstruction were reviewed by the experts in three rounds of surveys in complete anonymity. The statements were prepared by the working group based on previous literature or systematic reviews. Rating agreement through a Likert Scale: strongly agree, agree, neither agree or disagree, disagree and strongly disagree was used. To define consensus, it was established that the assertions should achieve a 75% of agreement or disagreement., Results: Of the 37 statements, 10 achieved unanimous consensus, 18 non-unanimous consensus and 9 did not achieve consensus. In the preoperative, the correction of the range of motion deficit, the previous high level of participation in sports and a better knowledge of the injury by the patient and compliance to participate in Rehabilitation were the statements that reached unanimous consensus. During the surgery, the treatment of associated injuries, as well as the use of autografts, and the addition of a lateral extra-articular tenodesis in some particular cases (active young athletes, <25 years old, hyperlaxity, high rotatory laxity and revision cases) obtained also 100% consensus. In the postoperative period, psychological readiness and its validation with scales, adequate physical preparation, as well as not basing the RTSS purely on the time of evolution after surgery, were the factors that reached unanimous Consensus., Conclusions: The consensus statements derived from this international ISAKOS leaders, may assist clinicians in deciding when to return to sports soccer in patients after an ACL reconstruction. Those statements that reached 100% consensus have to be strongly considered in the final decision to RTS soccer., Competing Interests: Declaration of competing interest None of the authors have a Conflict of interest related to this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to evaluate whether generalized joint hypermobility (GJH) influences postoperative results, including return to sport, patientreported outcomes, functional performance (hop tests), muscular strength, and the occurrence of ACL re-injury, in patients 1 year after anterior cruciate ligament (ACL) reconstruction., Methods: Data was extracted from a regional rehabilitation-specific registry containing information on patients with ACL injury. Patients between the ages of 16-50 years previously undergoing ACL reconstruction with available 1 year follow-up data were eligible for inclusion. Generalized joint hypermobility was assessed using the Beighton score (BS). Patients were examined one year postoperatively in terms of return to sport, patient-reported outcome, hop tests, muscular strength and the occurrence of reinjury. For purpose of analysis, patients were allocated into two groups, depending on the existence of GJH. The KOOS subscale of sports and recreation was considered the primary outcome. Analyses were performed both dichotomously and by using adjusted logistic regression, to consider potential confounders., Results: A total of 356 patients (41% males) were included, of which 76 (24% male) were categorized as having GJH. Patients with GJH had an inferior limb symmetry index preoperatively in terms of knee extension (mean 81.6 [SD 16.4] vs. 91.4 [SD 15.9], p = 0.02) and flexion strength (mean 91.9 vs. 99.1, p = 0.047) compared to patients without GJH. There was no difference between the groups in terms of the primary outcome, nor in any of the other postoperative outcomes. Nine patients (11.8%) in the group with GJH suffered ACL re-injury, compared with 13 patients (4.6%) in the control group (n.s.)., Conclusion: One year after ACL reconstruction the existence of GJH did not affect postoperative patient satisfaction, strength or functional outcome. No conclusive statements can be made regarding the influence of GJH on the risk of ACL re-injury in this particular study., Level of Evidence: Level II., (© 2022. The Author(s).)

Purpose: The aim of this study was to evaluate the clinical outcome at 5-year follow-up of a one-step procedure combining anterior cruciate ligament (ACL) reconstruction and partial meniscus replacement using a polyurethane scaffold for the treatment of symptomatic patients with previously failed ACL reconstruction and partial medial meniscectomy. Moreover, the implanted scaffolds have been evaluated by MRI protocol in terms of morphology, volume, and signal intensity., Methods: Twenty patients with symptomatic knee laxity after failed ACL reconstruction and partial medial meniscectomy underwent ACL revision combined with polyurethane-based meniscal scaffold implant. Clinical assessment at 2- and 5-year follow-ups included VAS, Tegner Activity Score, International Knee Documentation Committee (IKDC), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Lysholm Score. MRI evaluation of the scaffold was performed according to the Genovese scale with quantification of the scaffold's volume at 1- and 5-year follow-ups., Results: All scores revealed clinical improvement as compared with the preoperative values at the 2- and 5-year follow-ups. However, a slight, but significant reduction of scores was observed between 2 and 5 years. Concerning the MRI assessment, a significant reduction of the scaffold's volume was observed between 1 and 5 years. Genovese Morphology classification at 5 years included two complete resorptions (Type 3) and all the remaining patients had irregular morphology (Type 2). With regard to the Genovese Signal at the 5-year follow-up, three were classified as markedly hyperintense (Type 1), 15 as slightly hyperintense (Type 2), and two as isointense (Type 1)., Conclusion: Simultaneous ACL reconstruction and partial meniscus replacement using a polyurethane scaffold provides favourable clinical outcomes in the treatment of symptomatic patients with previously failed ACL reconstruction and partial medial meniscectomy at 5 years. However, MRI evaluation suggests that integration of the scaffold is not consistent., Level of Evidence: Level IV., (© 2022. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)

Background: The number of studies with a large cohort of patients that primarily focus on patient-reported outcomes after ACL reconstruction in children and adolescents is limited. The purpose of the present study was to determine whether patient age affects the proportion of patients that achieve a patient-acceptable symptom state (PASS) on the Knee injury and Osteoarthritis Outcome Score (KOOS) subscales one, two, five and 10 years after an ACL reconstruction., Methods: The patient data in the present study were extracted from the Swedish National Knee Ligament Register (SNKLR). Patients aged between five and 35 years that underwent a primary ACL reconstruction between 1 January 2005 and 31 December 2017 and had completed the KOOS questionnaire at the one-, two-, five- or 10-year follow-up were included. A total of 2,848 patients met the inclusion criteria and were included in the study; 47 paediatric patients (females 5-13, males 5-15 years), 522 adolescents (females 14-19, males 16-19 years) and 2,279 young adults (females 20-35, males 20-35 years). The results from the KOOS were presented as the mean and 95% confidence interval (CI) for the mean. For comparisons between groups, the chi-square test was used for non-ordered categorical variables. For pairwise comparisons between groups, Fisher's exact test (2-sided) was used for dichotomous variables. All the statistical analyses was set at 5%., Results: Adolescents reported a significantly lower score than young adults on the KOOS4 at the two- (68.4 vs. 72.1; P < 0.05), five- (69.8 vs. 76.0; P < 0.05) and 10-year follow-ups (69.8 vs. 78.2; P < 0.05). Moreover, a significantly smaller proportion of adolescents achieved a PASS on each of the KOOS subscales when compared with young adults at the five-year follow-up (Symptoms: 83.3% vs. 91.6%; Pain: 42.9% vs. 55.3%; Function in daily living: 31.4% vs. 41.1%; Function in sports and recreational activities: 42.3% vs. 55.7%; Knee-related quality of life: 50.0% vs. 65.0%; P < 0.05)., Conclusions: A significantly smaller proportion of adolescents achieved a PASS on each of the KOOS subscales when compared with young adults five years after ACL reconstruction. The results of the present study provide important information for physicians and physiotherapists treating young patients after an ACL injury and they can aid in providing realistic expectations in terms of the mid- and long-term outcomes., Level of Evidence: Prospective Observational Register/Cohort Study, Level II., (© 2022. The Author(s).)

Purpose: Correct placement of the femoral and tibial tunnels in the anatomic footprint during anterior cruciate ligament reconstruction (ACLR) is paramount for restoring rotatory knee stability. Recent studies have looked at surgeon volume and its outcomes on procedures such as total knee arthroplasty and infection rates, but only few studies have specifically examined tunnel placement after ACLR based on surgeon volume. The purpose of this study was to compare the placement of femoral and tibial tunnels during ACLR between high-volume and low-volume surgeons. It was hypothesized that high-volume surgeons would have more anatomic tunnel placement compared with low-volume surgeons., Methods: A retrospective review of all ACLR performed between 2015 and 2019 at an integrated health care system consisting of both academic and community hospitals with 68 orthopaedic surgeons was conducted. Surgeon volume was categorized as less than 35 ACLR per year (low volume) and 35 or more ACLR per year (high volume). Femoral tunnel placement for each patient was determined using an exact strict lateral radiograph (less than 6 mm of offset between the posterior halves of the medial and lateral condyles) taken after the primary ACLR using the quadrant method. The centre of the femoral tunnel was measured in relation to the posterior-anterior (PA) and proximal-distal (PD) dimensions (normal centre of anatomic footprint: PA 25% and PD 29%). Tibial tunnel placement for each patient was determined on the same lateral radiographs by measuring the mid-sagittal tibial diameter and the centre of the tibial attachment area of the ACL from the anterior tibial margin (normal centre of anatomic footprint: 43%). Each lateral radiograph was reviewed by one of two blinded reviewers., Results: A total of 4500 patients were reviewed, of which 645 patients met all the inclusion/exclusion criteria and were included in the final analysis. There were 228 patients in the low-volume group and 417 patients in the high-volume group. Low-volume surgeons performed a mean of 5 ACLRs per year, whereas surgeons in the high-volume group performed a mean of 40 ACLRs per year. In the PA dimension, the low-volume group had significantly more anterior femoral tunnel placement compared with the high-volume group (32 ± 10% vs 28 ± 9%, p < 0.01). In the PD dimension, the low-volume group had statistically significant more proximal femoral tunnel placement compared to the high-volume group (32 ± 9% vs 35 ± 9%, p < 0.01). For the tibial tunnel, the low-volume group had significantly more posterior tibial tunnel placement compared with the high-volume group (41 ± 10% vs 38 ± 7%, p < 0.01)., Conclusion: Low-volume surgeons placed their femoral tunnels significantly more anterior and proximal (high) during ACLR, and placed their tibial tunnels significantly more posterior, compared with high-volume surgeons. Prior research has indicated that anatomic placement of the femoral and tibial tunnels during ACLR leads to improved rotatory knee stability. The findings of this study demonstrate the importance of surgical volume and experience during ACLR., Level of Evidence: III., (© 2022. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)

Purpose: Anterior cruciate ligament (ACL) graft failure is a complication that may require revision ACL reconstruction (ACL-R). Non-anatomic placement of the femoral tunnel is thought to be a frequent cause of graft failure; however, there is a lack of evidence to support this belief. The purpose of this study was to determine if non-anatomic femoral tunnel placement is associated with increased risk of revision ACL-R., Methods: After screening all 315 consecutive patients who underwent primary single-bundle ACL-R by a single senior orthopedic surgeon between January 2012 and January 2017, 58 patients were found to have both strict lateral radiographs and a minimum of 24 months follow-up without revision. From a group of 456 consecutive revision ACL-R, patients were screened for strictly lateral radiographs and 59 patients were included in the revision group. Femoral tunnel placement for each patient was determined using a strict lateral radiograph taken after the primary ACL-R using the quadrant method. The center of the femoral tunnel was measured in both the posterior-anterior (PA) and proximal-distal (PD) dimensions and represented as a percentage of the total distance (normal center of anatomic footprint: PA 25% and PD 29%)., Results: In the PA dimension, the revision group had significantly more anterior femoral tunnel placement compared with the primary group (38% ± 11% vs. 28% ± 6%, p < 0.01). Among patients who underwent revision; those with non-traumatic chronic failure had statistically significant more anterior femoral tunnel placement than those who experienced traumatic failure (41% ± 13% vs. 35% ± 8%, p < 0.03). In the PD dimension, the revision group had significantly more proximal femoral tunnel placement compared with the primary group (30% ± 9% vs 38% ± 9%, p < 0.01)., Conclusion: In this retrospective study of 58 patients with successful primary ACL-R compared with 59 patients with failed ACL-R, anterior and proximal (high) femoral tunnels for ACL-R were shown to be independent risk factors for ACL revision surgery. As revision ACL-R is associated with patient- and economic burden, particular attention should be given to achieving an individualized, anatomic primary ACL-R. Surgeons may reduce the risk of revision ACL-R by placing the center of the femoral tunnel within the anatomic ACL footprint., Level of Evidence: Level III., (© 2021. European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)

Background: Although comparable clinical and functional outcomes have been reported after nonsurgical and surgical anterior cruciate ligament (ACL) treatment, few studies have investigated the effects of early versus late ACL reconstruction with initial rehabilitation., Purpose: To determine patient-reported knee function in patients who initially undergo nonreconstructive treatment after an ACL injury but who later choose to undergo ACL reconstruction as compared with (1) patients undergoing ACL reconstruction close to the index injury and (2) patients treated nonreconstructively at 1 to 10 years of follow-up., Study Design: Cohort study; Level of evidence, 2., Methods: Results from the Knee injury and Osteoarthritis Outcome Score (KOOS) were extracted from the Swedish National Knee Ligament Registry for patients treated with nonreconstruction, early ACL reconstruction, and initial nonreconstruction but subsequent ACL reconstruction (crossover group). The KOOS 4 (a mean of 4 KOOS subscales) was analyzed cross-sectionally at baseline and at the 1-, 2-, 5-, and 10-year follow-ups. Additionally, the Patient Acceptable Symptom State (PASS) was applied to all KOOS subscales from baseline to the 10-year follow-up., Results: A total of 1,074 crossover, 484 nonreconstruction, and 20,352 early ACL reconstruction cases were included. The crossover group reported lower KOOS 4 values than the group undergoing early ACL reconstruction at baseline and at all follow-ups (mean difference [95% CI]): baseline, -6.5 (-8.0 to -5.0); 1 year, -9.3 (-10.9 to -7.7); 2 years, -4.8 (-6.3 to -3.2); 5 years, -6.1 (-8.8 to -3.4); and 10 years, -10.9 (-16.3 to -5.2). Additionally, a smaller proportion of the crossover cohort achieved a PASS on KOOS subscales at baseline and through the 1-, 2-, 5-, and 10-year follow-ups as compared with the early ACL reconstruction cohort. No differences were observed between crossover and nonreconstruction cases on either the KOOS 4 or the PASS at any follow-up., Conclusion: A greater proportion of patients treated with early ACL reconstruction reported acceptable knee function and superior overall knee function as compared with patients who decided to cross over from nonreconstructive treatment to ACL reconstruction.

Clinical evaluation and management of anterior cruciate ligament (ACL) injury is one of the most widely researched topics in orthopedic sports medicine, giving providers ample data on which to base their practices. The ACL is also the most commonly treated knee ligament. This study reports on current topics and research in clinical management of ACL injury, starting with evaluation, operative versus nonoperative management, and considerations in unique populations. Discussion of graft selection and associated procedures follows. Areas of uncertainty, rehabilitation, and prevention are the final topics before a reflection on the current state of ACL research and clinical management of ACL injury. Level of evidence V., (© 2021. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)

A trend within the orthopedic community is rejection of the belief that "one size fits all." Freddie Fu, among others, strived to individualize the treatment of anterior cruciate ligament (ACL) injuries based on the patient's anatomy. Further, during the last two decades, greater emphasis has been placed on improving the outcomes of ACL reconstruction (ACL-R). Accordingly, anatomic tunnel placement is paramount in preventing graft impingement and restoring knee kinematics. Additionally, identification and management of concomitant knee injuries help to re-establish knee kinematics and prevent lower outcomes and registry studies continue to determine which graft yields the best outcomes. The utilization of registry studies has provided several large-scale epidemiologic studies that have bolstered outcomes data, such as avoiding allografts in pediatric populations and incorporating extra-articular stabilizing procedures in younger athletes to prevent re-rupture. In describing the anatomic and biomechanical understanding of the ACL and the resulting improvements in terms of surgical reconstruction, the purpose of this article is to illustrate how basic science advancements have directly led to improvements in clinical outcomes for ACL-injured patients.Level of evidenceV., (© 2021. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)

Treatment strategies for anterior cruciate ligament (ACL) injuries continue to evolve. Evidence supporting best practice guidelines for the management of ACL injury is to a large extent based on studies with low-level evidence. An international consensus group of experts was convened to collaboratively advance towards consensus opinions regarding the best available evidence on operative versus non-operative treatment for ACL injury.The purpose of this study was to report the consensus statements on operative versus non-operative treatment of ACL injuries developed at the ACL Consensus Meeting Panther Symposium 2019. Sixty-six international experts on the management of ACL injuries, representing 18 countries, convened and participated in a process based on the Delphi method of achieving consensus. Proposed consensus statements were drafted by the Scientific Organising Committee and Session Chairs for the three working groups. Panel participants reviewed preliminary statements prior to the meeting and provided initial agreement and comments on the statement via online survey. During the meeting, discussion and debate occurred for each statement, after which a final vote was then held. Eighty per cent agreement was defined a priori as consensus. A total of 11 of 13 statements on operative veresus non-operative treatment of ACL injury reached consensus during the symposium. Nine statements achieved unanimous support; two reached strong consensus; one did not achieve consensus; and one was removed due to redundancy in the information provided.In highly active patients engaged in jumping, cutting and pivoting sports, early anatomical anterior cruciate ligament reconstruction (ACLR) is recommended due to the high risk of secondary meniscus and cartilage injuries with delayed surgery, although a period of progressive rehabilitation to resolve impairments and improve neuromuscular function is recommended. For patients who seek to return to straight plane activities, non-operative treatment with structured, progressive rehabilitation is an acceptable treatment option. However, with persistent functional instability or when episodes of giving way occur, anatomical ACLR is indicated. The consensus statements derived from international leaders in the field will assist clinicians in deciding between operative and non-operative treatment with patients after an ACL injury.Level of evidence: V., Competing Interests: Competing interests: TD, BBR, ADL,ES, EHS, TR, SJM, MVP and JK: none declared. LE: Smith and Nephew: fellowship grant. ORA: Conmed: Speakers Bureau. DJO: honoraria; JWX: Arthrex: consulting fees, non-consulting fees, royalties; Trice Medical: consulting fees; FHF: Smith & Nephew: educational support, hospitality payments. VM: Smith & Nephew: educational support, consulting fees, speaking fee; Arthrex: educational support., (© International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine 2021. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)

Objective: To investigate the association between sustaining a second anterior cruciate ligament (ACL) injury and (1) time to return to sport, (2) symmetrical muscle function, and (3) symmetrical quadriceps strength at the time of return to sport in young athletes after primary ACL reconstruction., Design: Prospective cohort study., Methods: Patient demographics and results from 5 tests of muscle function (2 strength tests and 3 hop tests) were extracted from a rehabilitation registry. A questionnaire was sent to athletes (15-30 years old) who were involved in knee-strenuous sport before the injury and had undergone primary ACL reconstruction to determine time of return to knee-strenuous sport (preinjury Tegner Activity Scale score of 6 or greater). We used the Cox proportional hazard regression model to analyze time to event., Results: One hundred fifty-nine (32% of the initial sample) athletes (mean ± SD age, 21.5 ± 4.4 years; 64% female) were included. Athletes with a higher preinjury Tegner Activity Scale score had a higher rate of second ACL injury (hazard ratio = 2.1; 95% confidence interval: 1.2, 3.6; P <.01). Athletes who returned to knee-strenuous sport before 9 months after reconstruction had a higher rate of second ACL injury (hazard ratio = 6.7; 95% confidence interval: 2.6, 16.7; P <.001). There was no association between symmetrical muscle function or quadriceps strength and second ACL injury., Conclusion: Returning to knee-strenuous sport before 9 months after ACL reconstruction was associated with an approximately 7-fold increased rate of sustaining a second ACL injury. Achieving symmetrical muscle function or quadriceps strength was not associated with new ACL injury in young athletes. J Orthop Sports Phys Ther 2020;50(2):83-90. doi:10.2519/jospt.2020.9071 .

Purpose: This study aimed to determine the influence of femoral tunnel orientation on long-term clinical outcome and osteoarthritis in patients undergoing ACL reconstruction and to test the reliability of the implemented radiographic measurement methods. It was hypothesized that a more horizontal femoral tunnel would correlate with superior clinical outcome., Methods: A cohort of 193 patients who underwent non-anatomic ACL reconstruction was examined. In this specific study, non-anatomic is defined by the surgeons' pursuit of optimal isometry, not to emulate the native ACL anatomy. At follow-up, the Lachman test, the KT-1000, the pivot-shift test, the one-leg-hop test and the IKDC-2000 were evaluated. Osteoarthritis was evaluated radiographically. Posteroanterior and lateral radiographs were used to determine the position of the femoral tunnel in the coronal and sagittal planes and the angle of the tunnel in the coronal plane. A method for determining femoral rotation on the lateral radiographs was developed and its reliability was evaluated. The femoral tunnel orientation was analyzed to examine its influence on clinical outcome and osteoarthritis., Results: A total of 101 patients were analyzed at a mean of 16.4 (± 1.3) years postoperatively. The reliability of the measurement methods was regarded as good to excellent (ICC 0.57-0.97). The mean coronal femoral tunnel angle was 9.6° (± 9.4°). The coronal femoral tunnel was positioned at a mean of 43% (± 3.5%) of the distance measured from lateral to medial. The mean sagittal femoral tunnel position, measured using the quadrant method, was 40% (± 6.4%) from posterior to anterior. No significant associations were found between tunnel orientation and the clinical outcome variables., Conclusions: The orientation of the femoral tunnel did not predict the long-term subjective outcome, functional outcome or the development of osteoarthritis in patients undergoing non-anatomic ACL reconstruction. The method for determining femoral rotation on lateral radiographs was found to be reliable., Level of Evidence: Retrospective cohort study, level of evidence IV.

Background: It is important to investigate and compare graft diameters as well as graft types to identify risk factors for revision after an anterior cruciate ligament (ACL) reconstruction. We performed the current study in order to analyze the early ACL revision rate among patients treated with hamstring tendon (HT) autografts or patellar tendon (PT) autografts of different diameters. Our hypothesis was that an increase in both HT and PT autograft diameters would reduce the risk of early ACL revision., Methods: This retrospective study was based on prospectively collected data from the national knee ligament registries of Norway and Sweden and included patients who underwent primary ACL reconstruction during the period of 2004 through 2014. The primary end point was the 2-year incidence of ACL revision. The impact of graft type and diameter on the incidence of revision surgery was reported as relative risks (RRs) with 95% confidence intervals (CIs), estimated by using generalized linear models with a binomial distribution and log-link function., Results: Of 58,692 patients identified, a total of 18,425 patients were included in this study. The 2-year rate of ACL revision was 2.10% (PT autografts, 2.63%; HT autografts, 2.08%; RR = 0.93 [95% CI = 0.60 to 1.45]). There was an increased risk of ACL revision among patients treated with HT autografts with a diameter of <8 mm compared with larger HT autografts (RR = 1.25 [95% CI = 1.01 to 1.57]). Patients treated with HT autografts with a diameter of ≥9.0 mm or ≥10.0 mm had a reduced risk of early ACL revision compared with patients treated with PT autografts., Conclusions: Patients treated with larger-diameter HT autografts had a lower risk of early ACL revision compared with those treated with HT autografts of <8 mm. Patients treated with HT autografts of ≥9 or ≥10 mm had a reduced risk of early ACL revision compared with patients treated with PT autografts., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Objective: To present an overview of the Scandinavian knee ligament registers with regard to factors associated with additional ACL reconstruction, and studies comparing the Scandinavian registers with other knee ligament registers., Design: Systematic review., Data Sources: Four electronic databases: PubMed, EMBASE, the Cochrane Library and AMED were searched, and 157 studies were identified. Two reviewers independently screened titles, abstracts and full-text studies for eligibility. A modified version of the Downs and Black checklist was applied for quality appraisal., Eligibility Criteria for Selecting Studies: Eligible studies were those published since the establishment of the Scandinavian registers in 2004, which reported factors associated with additional ACL reconstruction and compared data from other registers., Results: Thirty-one studies met the inclusion criteria and generally displayed good reporting quality. Adolescent age (<20 years) was the most common factor associated with additional ACL reconstruction. The choice of hamstring tendon graft compared with patella tendon, transportal femoral tunnel drilling, smaller graft diameter and utilisation of suspensory fixation devices were associated with additional ACL reconstruction. Concomitant cartilage injury decreased the likelihood of additional ACL reconstruction. Patient sex alone did not influence the likelihood. The demographics of patients undergoing ACL reconstruction in the Scandinavian registers are comparable to registers in other geographical settings. However, there are differences in surgical factors including the presence of intra-articular pathology and graft choice., Summary: The studies published from the Scandinavian registers in general have a high reporting quality when regarded as cohort studies. Several factors are associated with undergoing additional ACL reconstruction. The results from the registers may help facilitate treatment decisions., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To perform a systematic review of findings from the Scandinavian knee ligament registers with regard to factors that affect patient reported outcome after anterior cruciate ligament (ACL) reconstruction., Design: Systematic review., Data Sources: Four electronic databases: PubMed, EMBASE, the Cochrane Library and AMED were searched, and 157 studies were identified. Two reviewers independently screened the titles, abstracts and full text articles for eligibility. A modified version of the Downs and Black checklist was applied for quality appraisal., Eligibility Criteria for Selecting Studies: Studies published from the Scandinavian registers from their establishment in 2004 and onwards that documented patient reported outcome and provided information on concomitant injuries were eligible., Results: A total of 35 studies were included. Younger age at ACL reconstruction, male sex, not smoking and receiving a hamstring tendon autograft positively influenced patient reported outcome. Patients with concomitant cartilage and meniscal injuries reported inferior subjective knee function compared with patients with an isolated ACL tear. One study reported that patients treated non-reconstructively reported inferior knee function compared with patients who had ACL reconstruction., Conclusion: Younger age, male sex, not smoking, receiving a hamstring tendon autograft and the absence of concomitant injuries were associated with superior patient reported outcomes after ACL reconstruction., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To determine preoperative predictors of long-term acceptable knee function and the development of osteoarthritis (OA) in long-term follow-up after anterior cruciate ligament (ACL) reconstruction., Methods: This study is a long-term follow-up of 2 previous randomized controlled trials that included 193 patients who underwent unilateral ACL reconstruction with ipsilateral hamstring tendon or patellar tendon autografts. Patients who suffered multiligament injuries, major meniscal injuries, chondral lesions requiring surgical treatment, or had a previous ACL reconstruction were excluded. Patient demographics, preoperative clinical assessments, and intraoperative findings were used to create stepwise multivariable regression models to determine the patient-acceptable symptom state (PASS) in the International Knee Documentation Committee and the development of OA defined as a Kellgren-Lawrence grade ≥2. Knee laxity measurements, hop performance, patient-reported outcome, and concomitant injuries were determined as variables., Results: A total of 147 patients (63.7% men) were eligible for inclusion, with a mean follow-up of 16.4 ± 1.3 years. The patients were an average age of 27.9 ± 8.3 years at the time of ACL reconstruction. One-half of the cohort reported an International Knee Documentation Committee evaluation system score above the PASS cutoff. The presence of a concomitant injury at operation (odds ratio [OR], 2.61; 95% confidence interval [CI], 1.10-6.21; P = .030) and greater preoperative anteroposterior laxity (OR, 1.87; 95% CI, 1.05-3.35; P = .034) increased the likelihood of achieving a PASS. A longer period between ACL injury and reconstruction (OR, 2.25; 95% CI, 1.02-5.00; P = .046) and older age at reconstruction (OR, 2.28; 95% CI, 1.34-3.86; P = .0023) increased the odds of developing OA at follow-up., Conclusions: Patients who were older at the time of ACL reconstruction and had waited >1 year between the injury and reconstruction ran an increased risk of having OA 16 years after reconstruction. One in 2 patients reported acceptable long-term knee function, but no risk factor for poorer subjective knee function was identified. Patients who had a minor concomitant injury and increased preoperative anteroposterior knee laxity had increased odds of reporting an acceptable long-term knee function., Level of Evidence: Level II; prospective comparative study., (Copyright © 2019 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

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 KOOS 4 (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 KOOS 4 . In addition, a higher preoperative body mass index was a significant risk factor for lower scores on 3 KOOS subscales and the KOOS 4 . 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.

Background: Increased postoperative rotatory knee laxity after anterior cruciate ligament (ACL) reconstruction may be associated with an increased risk of osteoarthritis and inferior subjective outcome, although long-term studies are lacking. In terms of anteroposterior knee laxity, this association has not yet been established. Purpose/Hypothesis: The purpose was to investigate whether postoperative knee laxity is associated with inferior long-term outcome in patients who have undergone ACL reconstruction. The hypothesis was that increased laxity would cause an inferior long-term clinical and radiographic outcome., Study Design: Cohort study; Level of evidence, 3., Methods: A total of 193 patients underwent ACL reconstruction and were examined at both 2 and 16 years postoperatively. At the 2-year follow-up, knee laxity was tested by use of the Lachman test, the anterior drawer test, the pivot-shift test, and the KT-1000 arthrometer. Outcome variables examined at the 16-year follow-up involved a radiographic assessment of osteoarthritis, patient-reported outcome measurements, and the single-legged hop test., Results: At the long-term follow-up, 147 (76%) patients were examined. The mean follow-up period for the included patients was 16.4 ± 1.2 years. A negative Lachman test at 2 years resulted in a superior International Knee Documentation Committee (IKDC) score (76.3 ± 19.4 vs 67.8 ± 19.3, P < .05) and Lysholm score (85.2 ± 11.9 vs 76.9 ± 17.8, P < .05) at the 16-year follow-up. Correspondingly, a negative anterior drawer test at 2 years was associated with a superior IKDC score (75.3 ± 18.7 vs 62.9 ± 20.2, P < .05) and Lysholm score (84.1 ± 12.1 vs 72.6 ± 20.2, P < .05) at 16 years. A negative pivot-shift test resulted in a superior IKDC score (74.5 ± 18.8 vs 46.9 ± 17.8, P < .05), a superior Lysholm score (83.3 ± 13.4 vs 58.9 ± 23.0, P < .05), and an increased level of activity (Tegner activity scale, median [range]: 4 [1-10] vs 3 [0-5], P < .05). Osteoarthritis was overrepresented in patients with positive manual knee laxity tests, but the difference was not statistically significant. The KT-1000 arthrometer result was not correlated with any outcome variables assessed in this study., Conclusion: Increased manual anteroposterior and rotatory knee laxity 2 years after ACL reconstruction is associated with an inferior long-term subjective outcome.

Background: There is insufficient knowledge about the way that concomitant injuries affect the short-term likelihood of a return to a knee-strenuous sport after anterior cruciate ligament (ACL) reconstruction. Hypotheses/Purpose: The purpose was to study whether patient characteristics, concomitant injuries, and graft choice at primary ACL reconstruction can predict return to sport (RTS) 1 year after surgery. The hypotheses were that younger age at the time of ACL reconstruction would positively affect RTS, while the presence of concomitant injuries would negatively affect RTS 1 year after surgery., Study Design: Case-control study; Level of evidence, 3., Methods: Data were extracted from a rehabilitation-specific register and the Swedish National Knee Ligament Register. Twelve months after surgery, all patients were evaluated for RTS via the Tegner Activity Scale. The primary outcome was a return to knee-strenuous sport, defined as a Tegner Activity Scale ≥6. Univariable and multivariable logistic regression analyses were performed with patient characteristics, concomitant knee injuries, and graft choice as independent variables., Results: A total of 272 patients (51% female) with a mean ± SD age of 25.0 ± 9.2 years were included. In the multivariable analysis, a favorable odds ratio (OR) for returning to sport was found for patients of male sex (OR, 2.58; 95% CI, 1.43-4.65; P = .0016), younger age at the time of ACL reconstruction (OR, 2.32; 95% CI, 1.59-3.33; P < .0001), a higher preinjury score on the Tegner Activity Scale (OR, 1.45; 95% CI, 1.13-1.87; P = .0038), and an absence of injury to the meniscus (OR, 1.92; 95% CI, 1.10-3.36; P = .023) and medial collateral ligament (OR, 7.61; 95% CI, 1.42-40.87; P = .018). In addition, the absence of cartilage injury was favorable in terms of RTS in the univariable analysis (OR, 2.48; 95% CI, 1.40-4.39; P = .0018)., Conclusion: Positive predictors of a return to knee-strenuous sport 1 year after ACL reconstruction were male sex, younger age, a high preinjury level of physical activity, and the absence of concomitant injuries to the medial collateral ligament and meniscus.

Objective: Findings from individual anterior cruciate ligament reconstruction (ACLR) registry studies are impactful, but how various registries from different countries compare with different patient populations and surgical techniques has not been described. We sought to describe six ACLR registry cohorts to understand variation across countries., Methods: Five European registries and one US registry participated. For each registry, all primary ACLR registered between registry establishment through 31December 2014 were identified. Descriptive statistics included frequencies, proportions, medians and IQRs. Revision incidence rates following primary ACLR were computed., Results: 101 125 ACLR were included: 21 820 in Denmark, 300 in Luxembourg, 17 556 in Norway, 30 422 in Sweden, 2972 in the UK and 28 055 in the US. In all six cohorts, males (range: 56.8%-72.4%) and soccer injuries (range: 14.1%-42.3%) were most common. European countries mostly used autografts (range: 93.7%-99.7%); allograft was most common in the US (39.9%). Interference screw was the most frequent femoral fixation in Luxembourg and the US (84.8% and 42.9%), and suspensory fixation was more frequent in the other countries (range: 43.9%-75.5%). Interference was the most frequent tibial fixation type in all six cohorts (range: 64.8%-98.2%). Three-year cumulative revision probabilities ranged from 2.8% to 3.7%., Conclusions: Similarities in patient demographics and injury activity were observed between all cohorts of ACLR. However, graft and fixation choices differed. Revision rates were low. This work, including >100 000 ACLR, is the most comprehensive international description of contemporary practice to date., Competing Interests: Competing interests: FSH’s department receives research support and royalties from Smith & Nephew, Stryker, MatOrtho and Corin. None of these are directly linked to the current project. LE receives research grants from Smith & Nephew, Arthrex and Biomet/Zimmer. None of these grants are directly linked to the current project. JK is editor-in-chief of Knee Surgery, Sports Traumatology, Arthroscopy., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: The purpose of this systematic review was to comprehensively assess the quality of reporting of randomized controlled trials (RCTs) relating to anterior cruciate ligament (ACL) reconstruction. Specifically, this review explored factors related to the quality of the RCTs and trends in the quality of reporting over time., Methods: The online databases PubMed, Ovid (MEDLINE), and Embase were used to search for all RCTs on the topic of ACL reconstruction from database inception until April 14, 2016. The quality of reporting was evaluated using the Detsky quality index and the Consolidated Standards of Reporting Trials (CONSORT) checklist for reporting trials of nonpharmacologic treatments. A multivariate regression analysis was used to assess predictors of quality reporting., Results: The online search yielded 2,933 articles, 412 of which met the inclusion criteria and were assessed for quality of reporting. There was a significant (p < 0.0001) increase in the number of RCTs published over time. The mean Detsky score (and standard deviation) across all included RCTs was 68.9% ± 13.2%. The strongest predictors of quality reporting were the inclusion of a CONSORT flow diagram (β-coefficient, 10.0; 95% confidence interval [CI]: 8.45 to 11.61; p < 0.0001) and being published in the year 2009 or later (β-coefficient, 5.2; 95% CI: 3.87 to 6.45; p < 0.0001). The factors demonstrating the greatest improvement over time were the inclusion of a full description of the randomization procedure (p = 0.001) and prospective calculation of the sample size (p = 0.002)., Conclusions: There has been a significant increase in both the quantity and quality of RCTs relating to ACL reconstruction over time. Specifically, the reporting of a methodologically sound randomization process and prospective calculation of sample size have significantly improved in recent years. However, since the year 2009, the number of trials and reporting in these trials has remained relatively consistent. The use of a CONSORT flow diagram is a strong predictor of high-quality reporting.

Purpose: To characterise patients who returned to knee-strenuous sports after an anterior cruciate ligament (ACL) reconstruction., Methods: Data from isotonic tests of muscle function and patient-reported outcome measures, Tegner activity scale (Tegner and Lysholm in Clin Orthop Relat Res 198:43-49, 1985), physical activity scale, knee injury and osteoarthritis scale and knee self-efficacy scale were extracted from a registry. The 157 included patients, 15-30 years of age, had undergone primary ACL reconstruction and were all involved in knee-strenuous sports, i.e. pre-injury Tegner of 6 or higher. Return to sport was studied in two different ways: return to pre-injury Tegner and return to knee-strenuous sport (Tegner 6)., Results: Fifty-two patients (33 %), who returned to pre-injury Tegner, 10 months after surgery, were characterised by better subjective knee function measured with the knee injury and osteoarthritis outcome score (p < 0.05), compared with patients who did not. These patients also had higher perceived self-efficacy of knee function (p < 0.01), measured with knee self-efficacy scale. Eighty-four patients (54 %) who returned to knee-strenuous sports, i.e. Tegner 6 or higher, were characterised by higher goals for physical activity (p < 0.01) and higher self-efficacy of future knee function (p < 0.05). Strength measurements showed that women who returned to sports were stronger in leg extension than women who did not. No differences were found in Limb Symmetry Index for knee strength or jumping ability., Conclusion: Patients who returned to sports after ACL reconstruction had better subjective knee function and higher self-efficacy of knee function. Results highlight that further emphasis should be placed at psychological factors during rehabilitation of patients after ACLR., Level of Evidence: II.

Purpose: The purpose was to compare revision rates and patient-reported outcomes between single- and double-bundle anterior cruciate ligament (ACL) reconstructions., Methods: All patients from the Swedish National Knee Ligament Register from 2005 through 2011 who underwent primary ACL reconstruction with hamstring autografts were included. Patients with concomitant injuries, except meniscal and chondral injuries, were excluded. By December 31, 2011, 16,791 primary isolated ACL reconstructions had been registered, of which 16,281 were single-bundle and 510 were double-bundle. Cumulative revision rates were estimated using Kaplan-Meier analysis. The Knee injury and Osteoarthritis Outcome Score (KOOS) and EQ-5D were calculated at 1- and 2-year follow-ups., Results: The revision rate showed no statistically significant differences between the groups (P = .30). Over the 7-year observation period, 347 single-bundle (2.1%) and 8 double-bundle (1.6%) ACL reconstructions were revised. No significant differences in the KOOS or EQ-5D were found between the groups postoperatively. In addition, there were no differences in postoperative improvements in the KOOS or EQ-5D at 1- and 2-year follow-ups., Conclusions: Revision rates after single- and double-bundle ACL reconstructions were low. No differences were found in revision rates, KOOS, and EQ-5D between the 2 techniques., Level of Evidence: Level III, retrospective comparative study., (Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Background: Identifying predictors of contralateral anterior cruciate ligament (ACL) reconstruction is important to focus preventive strategies and related research on high-risk groups., Purpose: To investigate predictors of contralateral ACL reconstruction in patients who have already undergone a primary ipsilateral reconstruction., Study Design: Cohort study; Level of evidence, 2., Methods: This study was based on data from the Swedish National Knee Ligament Register from January 1, 2005, to December 31, 2013. Patients aged 13 to 59 years who underwent primary ipsilateral (index) ACL reconstruction with hamstring tendon or bone-patellar tendon-bone autografts were included. Follow-up started on date of index ACL reconstruction and ended either with primary contralateral ACL reconstruction, after 5 years of follow-up, or on December 31, 2013, whichever occurred first. The investigated variables were patient sex, age at index reconstruction, activity at the time of index injury, timing of surgery, graft selection, graft harvest site, and meniscal and chondral injury. The study end point was primary contralateral ACL reconstruction. Relative risks (RRs) and 95% CIs were calculated and adjusted for confounding factors using multivariate statistics., Results: A total of 9061 participants were included (n = 5196 males [57.3%] and 3865 females [42.7%]), of which 270 participants (3.0%) underwent primary contralateral ACL reconstruction during the 5-year follow-up. There was no difference in contralateral reconstruction rates between males and females (3.0% vs 2.9%, P = .695). Age <20 years significantly increased the risk of contralateral reconstruction (males: RR = 2.4 [95% CI, 1.7-3.4] and females: RR = 2.9 [95% CI, 1.9-4.5]; P < .001). Among female patients undergoing reconstruction using autograft hamstring, harvest of a contralateral hamstring tendon significantly increased this risk (RR = 3.4 [95% CI, 1.4-7.9]; P = .006)., Conclusion: In both male and female participants, age <20 years predicted an almost 3 times higher 5-year risk of contralateral ACL reconstruction. Among female participants undergoing reconstruction with autograft hamstring, a contralateral harvest predicted a more than 3 times higher 5-year risk of contralateral ACL reconstruction. Patient sex, activity at the time of index injury, graft selection, meniscal injury, and chondral injury were not predictors of contralateral ACL reconstruction., (© 2014 The Author(s).)

Background: Revision surgery is one of the most important endpoints during follow-up after anterior cruciate ligament (ACL) reconstruction., Purpose: To investigate if commonly known patient factors can predict revision surgery after ACL reconstruction., Study Design: Cohort study; Level of evidence, 2., Methods: This prospective cohort study was based on data from the Swedish National Knee Ligament Register during the period of January 1, 2005, through December 31, 2013. Patients who underwent primary ACL reconstruction with hamstring tendon or bone-patellar tendon-bone autografts were included. Follow-up started on the date of primary ACL reconstruction, and follow-up ended with ACL revision surgery, after 24 months of follow-up, or on December 31, 2013, whichever occurred first. The analyzed patient variables were activity at the time of injury, sex, age, height, weight, body mass index, smoking, and the use of smokeless tobacco. The primary study endpoint was revision surgery, defined as replacement of a primary ACL reconstruction. Relative risk (RR) and 95% CIs were calculated and adjusted for confounding factors using multivariate statistics., Results: A total of 16,930 patients were included (males, n=9767 [57.7%]; females, n=7163 [42.3%]). The 2-year revision rate was 1.82% (95% CI, 1.62%-2.02%). There was no significant difference between male and female revision rates (1.74% [95% CI, 1.48%-2.00%] vs 1.93% [95% CI, 1.61%-2.25%], P=.383). In both males and females there was a significantly increased risk of revision surgery associated with soccer playing and adolescence (age 13-19 years) (males: RR=1.58 [95% CI, 1.12-2.23], P=.009 and RR=2.67 [95% CI, 1.91-3.73], P<.001, respectively; females: RR=1.43 [1.01-2.04], P=.045 and RR=2.25 [95% CI, 1.57-3.24], P<.001, respectively). A combination of these predictors were associated with a further increased risk of revision surgery (males: RR=2.87 [95% CI, 1.79-4.60], P<.001; females: RR=2.59 [95% CI, 1.69-3.96], P<.001)., Conclusion: Soccer players and adolescents had an increased risk of revision surgery after ACL reconstruction, with a respective factor of 1.5 and 2.5. Individuals with a combination of these 2 predictors carried an almost 3-fold higher risk of revision surgery. There were no significant associations for sex, height, weight, body mass index, or tobacco use., (© 2014 The Author(s).)

Unlabelled: The pivot shift test is the only physical examination test capable of predicting knee function and osteoarthritis development after an ACL injury. However, because interpretation and performance of the pivot shift are subjective in nature, the validity of the pivot shift is criticized for not providing objective information for a complete surgical planning for the treatment of rotatory knee laxity. The aim of ACL reconstruction was eliminating the pivot shift sign. Many structures and anatomical characteristics can influence the grading of the pivot shift test and are involved in the genesis and magnitude of rotatory instability after an ACL injury. The objective quantification of the pivot shift may be able to categorize knee laxity and provide adequate information on which structures are affected besides the ACL. A new algorithm for rotational instability treatment is presented, accounting for patients' unique anatomical characteristics and objective measurement of the pivot shift sign allowing for an individualized surgical treatment., Level of Evidence: V.

Purpose: The purpose of the study was to analyze the baseline variables and clinical outcomes for almost 24,000 patients entered into the Swedish National ACL Register between January 2005 and December 2012., Methods: The register consists of 2 parts: 1 section in which surgeons report baseline and surgical data and 1 section in which patients report the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the EQ-5D score before and 1, 2, and 5 years after surgery., Results: By December 2012, 23,744 patients had been entered into the surgeons' part of the register. The female-male ratio in the register is 42:58. The mean age at primary anterior cruciate ligament (ACL) reconstruction was 26 years (SD, 11 years) and 28 years (SD, 9 years) for the female and male patients, respectively. The ACL injury occurred during soccer in 36% of the female patients and 49% of the male patients. In 2012, 95% of the primary ACL reconstructions were performed using hamstring tendon autografts. For patients who had a minimum of 5 years' follow-up, the revision rate was 3.3% and the contralateral reconstruction rate was 3.8%. On all follow-up occasions up to 5 years, patients who had undergone revision had a significantly (P < .001) poorer outcome than those who had undergone primary unilateral ACL reconstructions in all KOOS and EQ-5D dimensions. On all follow-up occasions, smokers obtained significantly poorer scores than nonsmokers in terms of both the KOOS (P < .008) and the EQ-5D (P < .024)., Conclusions: Soccer is the most common cause of injury in both female and male patients, and patients undergoing revisions fare less well than those undergoing primary unilateral ACL reconstructions, as well as bilateral reconstructions. Furthermore, smokers fare less well than nonsmokers. The cumulative risk of an ACL revision or contralateral ACL reconstruction during a 5-year period is approximately 7%. For patients aged younger than 19 years, the cumulative risk is significantly higher., Level of Evidence: Level II, retrospective prognostic study., (Copyright © 2014 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: In August 2011, orthopaedic surgeons from more than 20 countries attended a summit on anatomic anterior cruciate ligament (ACL) reconstruction. The summit offered a unique opportunity to discuss current concepts, approaches, and techniques in the field of ACL reconstruction among leading surgeons in the field., Methods: Five panels (with 36 panellists) were conducted on key issues in ACL surgery: anatomic ACL reconstruction, rehabilitation and return to activity following anatomic ACL reconstruction, failure after ACL reconstruction, revision anatomic ACL reconstruction, and partial ACL injuries and ACL augmentation. Panellists' responses were secondarily collected using an online survey., Results: Thirty-six panellists (35 surgeons and 1 physical therapist) sat on at least one panel. Of the 35 surgeons surveyed, 22 reported performing "anatomic" ACL reconstructions. The preferred graft choice was hamstring tendon autograft (53.1 %) followed by bone-patellar tendon-bone autograft (22.8 %), allograft (13.5 %), and quadriceps tendon autograft (10.6 %). Patients generally returned to play after an average of 6 months, with return to full competition after an average of 8 months. ACL reconstruction "failure" was defined by 12 surgeons as instability and pathological laxity on examination, a need for revision, and/or evidence of tear on magnetic resonance imaging. The average percentage of patients meeting the criteria for "failure" was 8.2 %., Conclusions: These data summarize the results of five panels on anatomic ACL reconstruction. The most popular graft choice among surgeons for primary ACL reconstructions is hamstring tendon autograft, with allograft being used most frequently employed in revision cases. Nearly half of the surgeons surveyed performed both single- and double-bundle ACL reconstructions depending on certain criteria. Regardless of the technique regularly employed, there was unanimous support among surgeons for the use of "anatomic" reconstructions using bony and soft tissue remnant landmarks.

Background: An important objective of anterior cruciate ligament (ACL) registries is to detect and report early graft failure and revision surgery after ACL reconstruction., Purpose: To investigate surgical variables and identify predictors of revision surgery after ACL reconstruction., Study Design: Prospective cohort study; Level of evidence, 2., Methods: This prospective cohort study was based on data from the Swedish National Knee Ligament Register during the years 2005 through 2011. Eight surgical variables were investigated: graft selection, graft width, single-bundle or double-bundle techniques, femoral graft fixation, tibial graft fixation, injury-to-surgery interval, injuries to menisci, and injuries to cartilage. The primary endpoint was the 2-year incidence of revision surgery. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated and adjusted for confounders by use of multivariate statistics., Results: A total of 13,102 patients were included (5541 women [42%] and 7561 men [58%]; P < .001). Hamstring tendon autografts accounted for 90% (11,764 patients) of all reconstructions, of which 96% were performed with a single-bundle technique (11,339 patients). Patellar tendon autografts accounted for the remaining 10% (1338 patients). At index reconstruction, observed injuries to menisci and cartilage were common (40% and 28%, respectively). The overall 2-year incidence of revision surgery was 1.60% (women, 1.57%; men, 1.63%; P = .854). Patients with metal interference screw fixation of a semitendinosus tendon autograft on the tibia had a significantly reduced risk of early revision surgery (RR = 0.32; 95% CI, 0.12-0.90; P = .031)., Conclusion: Metal interference screw fixation of a semitendinosus tendon autograft on the tibia was an independent predictor of significantly lower 2-year incidence of revision surgery. Graft selection, graft width, a single-bundle or a double-bundle technique, femoral graft fixation, the injury-to-surgery interval, and meniscus injury were not predictors of early revision surgery., (© 2014 The Author(s).)

Purpose: To investigate and analyse outcomes of patients over the age of 40 who had undergone anterior cruciate ligament (ACL) reconstruction and to compare them to their younger counterparts. We analysed patient-reported outcomes measured using the knee injury and osteoarthritis outcome score (KOOS) as well as aetiology of injury, concomitant intra-articular injuries and time from injury to surgery., Methods: Data were extracted from the Swedish National Knee Ligament Register during the period of 2005 through 2012. The following data were extracted and analysed: patient age, gender, activity at the time of injury, time between injury and reconstruction, concomitant intra-articular injuries, graft size used for reconstruction and KOOS measured pre-operatively as well as 1, 2 and 5 years post-operatively. The cohort was stratified into age groups of 0-19, 20-29, 30-39 and ≥ 40 years of age., Results: Pivoting sports were dominating as the cause of ACL injury in the younger age groups (up to 39 years). Alpine skiing and other non-specified activities were the most common causes in the older age group (≥ 40 years). Pre-operative KOOS was significantly lower in older age groups (p < 0.01). Post-operative KOOS regarding all subscales was significantly better in the older age group. The improvement in KOOS was significant with increasing age (p < 0.01). Older patients exhibited the greatest improvement in KOOS for all subscales at 1, 2 and 5 years post-operative follow-ups compared with pre-operative values (p < 0.01). Older patients had more cartilage injuries pre-operatively compared with younger patients. The same trend was observed in the older group for meniscus injury with and without cartilage injuries. The diameter of the graft used for ACL reconstruction was significantly larger in the older age groups and largest in the age group ≥ 40 years (p < 0.01). Older patients waited significantly longer for surgery after the ACL injury (p < 0.01)., Conclusion: In the older age groups, patients reported lower pre-operative KOOS compared with their younger counterparts. At follow-up, KOOS was similar in all age groups. From these results, we can therefore conclude that our hypothesis confirmed that optimal surgical results can in fact be achieved even in older patients.

Background: The aim of the study was to compare the results after arthroscopic anterior cruciate ligament (ACL) reconstruction using either the double-bundle or single-bundle technique with hamstring tendon autografts in an unselected group of patients., Hypothesis: Double-bundle ACL reconstruction will render a better outcome on the pivot-shift test., Study Design: Randomized controlled trial; Level of evidence, 1., Methods: A randomized series of 103 patients (33 women, 70 men; median age, 27 years; range, 18-52 years) with a unilateral ACL rupture underwent anatomic ACL reconstruction. The double-bundle technique was used in 53 patients, and the single-bundle technique was used in 50 patients. The ACL footprint was visualized, and the femoral tunnel was drilled through the anteromedial portal; interference screw fixation was used at both ends. The patients were examined preoperatively and at a median of 26 months (range, 22-42 months) after the reconstruction by a blinded observer. The primary variable was the pivot-shift test., Results: At 2-year follow-up, 98 patients (93%) were examined. Clinical assessments at follow-up revealed no significant differences between the double-bundle and single-bundle groups in terms of the pivot-shift test, KT-1000 arthrometer laxity measurements, manual Lachman test, range of motion, Lysholm knee scoring scale, Tegner activity scale, Knee Injury and Osteoarthritis and Outcome Score (KOOS), 1-legged hop test, and square hop test. A significant improvement was seen in both groups compared with the preoperative values in terms of most clinical assessments., Conclusion: In this prospective randomized study, the primary variable, the pivot-shift test, and other subjective and objective outcome variables revealed no significant differences between the double-bundle and single-bundle techniques at 2 years after ACL reconstruction in an unselected group of patients.

Purpose: We aimed to perform a systematic review of the literature concerned with timing of surgery after anterior cruciate ligament injury., Methods: A systematic electronic search in Medline through PubMed, Embase, and the Cochrane Library was carried out in October 2011. All English-language randomized controlled clinical trials, prospective comparative cohort studies, and prognostic and diagnostic studies published from January 1995 to August 2011 were eligible for inclusion. All articles addressing timing of surgery were eligible for inclusion regardless of injury-to-surgery interval, graft type, surgical technique, or rehabilitation. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist guided the reporting and data abstraction. Methodologic quality of all included articles was carefully assessed., Results: We included 22 articles (3,583 patients) in the systematic review. Study design, research methodology, surgical technique, and outcome measurements differed greatly among included articles. The injury-to-surgery interval, classified as early and delayed, ranged from within 2 days to 7 months and 3 weeks to 24 years, respectively. Eight articles promoted early reconstruction, whereas the majority of articles found no difference in outcome between early and delayed surgery. Two articles were inconclusive., Conclusions: There were few or no differences in subjective and objective outcomes related to timing of anterior cruciate ligament reconstruction., Level of Evidence: Level II, systematic review of Level I and II studies., (Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Published papers on anatomic anterior cruciate ligament (ACL) reconstruction often lack details in the description of the surgical procedure, and there are large variations in anatomic ACL reconstruction techniques. We aimed to develop a validated checklist to be used for anatomic ACL reconstruction. First, a list of all potential items that could be used in the checklist was generated. Thirty-four ACL experts were selected to participate in an anonymous online survey to rate the importance of these items on a scale of 1 to 4 (with a score of 4 having the most importance). The results were verified by surveying a large sample of 959 orthopaedic specialists who are peer reviewers for four major orthopaedic journals. Items were included in the final checklist if they received an importance score of 3 or 4 from at least 75% of the survey takers. The survey response rate was 79% (twenty-seven of thirty-four) of the ACL experts and 40% (379 of 959) of the peer reviewers. The final Anatomic ACL Reconstruction Checklist includes seventeen items with a maximum score of 19 points. The final checklist underwent preliminary testing for internal consistency, intertester reliability, and validity. Cronbach's alpha for internal consistency was 0.82, and the intraclass correlation coefficient (ICC) for intertester reliability was 0.65. This large survey-based study on anatomic ACL reconstruction resulted in the development of the Anatomic ACL Reconstruction Checklist; preliminary evidence for interpretation of the scores is provided.

Background: There have been numerous studies on anterior cruciate ligament (ACL) reconstruction. Considering the vast number of studies, a quick assessment reveals rather few with a high level of evidence., Purpose: The primary aim was to categorize the study type and level of evidence of studies on primary ACL reconstruction by applying the level of evidence rating system proposed by the Oxford Centre for Evidence-Based Medicine. The secondary aims were to correlate the level of evidence with the impact factor of the journal, to evaluate the level of evidence over time, and to evaluate the geographic distribution of the included studies., Study Design: Systematic review., Methods: An electronic search was performed using the databases PubMed, EMBASE, and Cochrane Library. Studies published from January 1995 to August 2011 were included. Therapeutic studies written in English that report on isolated primary ACL reconstruction with clinical outcome measurements related to the reconstruction were included. Categorization and implementation of the level of evidence were performed. Correlation between the level of evidence and the impact factor of the journal was analyzed together with linear regression models to reveal any significant trends over time., Results: A total of 7154 studies were analyzed, of which 1510 were included. Analysis of the study types revealed that case series (n = 494; 32.7%) was the most frequent study type. Randomized controlled trials represented 9.2% (n = 139) of the sample, whereas meta-analyses were rare. Single-bundle studies were the most common studies (n = 1333; 88.3%), followed by double-bundle (n = 98; 6.5%) and single- versus double-bundle (n = 79; 5.2%). The journals Arthroscopy, Knee Surgery Sports Traumatology Arthroscopy (KSSTA), and American Journal of Sports Medicine (AJSM) represented 43.5% (n = 657) of the included studies. Arthroscopy had the highest number of publications in general and in level 4 and 5 studies, whereas AJSM had the lowest number of the 3. AJSM had the highest number of level 1 and 2 studies in general. The mean level of evidence calculated without level 5 studies was 3.15 for Arthroscopy, 3.20 for KSSTA, and 2.9 for AJSM. There was a significant correlation (P < .05) between the impact factor of the journal and mean level of evidence of the journal and the proportion high level of evidence studies (levels 1 and 2). There was a significant (P < .05) trend toward higher mean level of evidence over time., Conclusion: Most therapeutic studies on primary ACL reconstruction were of low level of evidence, and there was a positive correlation between the journal's impact factor and the mean level of evidence and the proportion of high level of evidence studies. There was significant trend toward higher mean level of evidence over time.

Evaluation of injured-knee laxity is essential for treatment selection, clinical follow-up, and research. Interest in rotatory knee laxity increased with implementation of anatomic anterior cruciate ligament reconstruction. The pivot shift test represents a link between static testing with 1° of freedom and dynamic testing during functional activity. Difficulties lie in standardizing the performance of the pivot shift test and extracting measurable and relevant kinematic data. Noninvasive methodologies based on electromagnetic or acceleration sensors can evaluate the pivot shift in a quantitative and reliable manner. Further validation and reliability testing of devices for examination of rotatory laxity is warranted., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Many surgeons intend to replicate the native anterior cruciate ligament (ACL) as much as possible, aiming at anatomic ACL reconstruction. An outline of new surgical preferences is starting to form; orthopedic surgeons have shifted their preferences in arthroscopic technique, graft type, and fixation during the past decade. The days of simple silk suturing of the native ACL stump to the femoral periosteum are over. Today, knee surgeons performing ACL reconstruction have a wide array of technical considerations, graft choices, and fixation techniques at hand that enable them to specifically tailor each reconstruction to each patient's anatomy and specific needs., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: The Swedish National Anterior Cruciate Ligament Register provides an opportunity for quality surveillance and research., Purpose: The primary objective was to recognize factors associated with a poorer outcome at an early stage., Study Design: Case series; Level of evidence, 4., Methods: Registrations are made using a web-based protocol with 2 parts: a patient-based section with self-reported outcome scores and a surgeon-based section, where factors such as cause of injury, previous surgery, time between injury and reconstruction, graft selection, fixation technique, and concomitant injuries are reported. The self-reported outcome scores are registered preoperatively and at 1, 2, and 5 years., Results: Approximately 90% of all anterior cruciate ligament (ACL) reconstructions performed annually in Sweden are reported in the register. Registrations during the period 2005-2010 were included (n = 17,794). After excluding multiligament reconstructions and reoperations, the male:female ratio was 57.5:42.5 for both primary (n = 15,387) and revision (n = 964) surgery. The cause of injury was soccer in approximately half the male patients and in one third of the female patients. All subscales of the Knee injury and Osteoarthritis Outcome Score (KOOS) were significantly improved 1, 2, and 5 years postoperatively in patients undergoing primary reconstructions. In terms of the KOOS, revisions did significantly less well than primary reconstructions on all follow-up occasions, and smokers fared significantly less well than nonsmokers both preoperatively and at 2 years. Patients who had concomitant meniscal or chondral injuries at reconstruction did significantly less well preoperatively and at 1 year in terms of most KOOS subscales compared with patients with no such injuries. At 5 years, a significant difference was only found in terms of the sport/recreation subscale. Double-bundle reconstructions revealed no significant differences in terms of all the KOOS subscales at 2 years compared with single-bundle reconstructions (114 double-bundle vs 5109 single-bundle). During a 5-year period, 9.1% (contralateral, 5.0%; revision, 4.1%) of the patients underwent a contralateral ACL reconstruction or revision reconstruction of the index knee. The corresponding figure for 15- to 18-year-old female soccer players was 22.0%., Conclusion: Primary ACL reconstruction significantly improves all the subscales of the KOOS. Young female soccer players run a major risk of reinjuring their ACL or injuring the contralateral ACL; revision ACL reconstructions do less well than primary reconstructions, and smokers do less well than nonsmokers.

The aim of this retrospective study was to compare the results after arthroscopic anterior cruciate ligament (ACL) reconstruction using the four-strand semitendinosus-gracilis (ST/G) autograft in male (n=141) vs female (n=103) patients. The patients were operated on between 1996 and 2005, using interference screw fixation and drilling the femoral tunnel through the anteromedial portal. The pre-operative assessments and demographics, apart from age (males 29 years, females 26 years; P=0.02), were comparable at the time of surgery. At 25 (23-36) months post-operatively, no significant differences were found between the study groups in terms of anterior side-to-side knee laxity, manual Lachman test, Tegner activity level, Lysholm knee score, range of motion or donor-site morbidity. Both study groups improved significantly in most clinical assessments and functional scores compared with their pre-operative values. Two years after ACL reconstruction using ST/G autografts, there were no significant differences between male and female patients in terms of clinical outcome or functional scores., (© 2011 John Wiley & Sons A/S.)

Purpose: The purpose of this prospective study was to describe the variability in leg muscle power and hop performance up to 2 years among patients following ACL reconstruction and specifically to illustrate the effects of various criteria for an acceptable level of muscle function., Methods: Eighty-two patients (56 men and 26 women)with a mean age of 28 years, who underwent ACL reconstruction using either hamstring tendons (n = 46) or a patellar tendon (n = 36), were assessed pre-operatively and 3, 6, 12 and 24 months post-surgery with a battery of three lower extremity muscle power tests and a battery of three hop tests., Results: Leg symmetry index (LSI) values at group level ranged between 73 and 100% at all follow-ups. When the tests were evaluated individually, patients reached an average LSI of ≥ 90% at 24 months. The success rate at 24 months for the muscle power test battery, that is,patients with an LSI of ≥ 90% in all three tests, was 48 and 44% for the hop test battery. The success rate at 24 months for both test batteries on all six muscle function tests was 22%. The criterion of an LSI of ≥ 80% resulted in 53% of the patients having an acceptable level on all six tests,while with a criterion of an LSI of ≥ 100%, none of the patients reached an acceptable level., Conclusion: At group level and in single muscle function tests, the muscle function outcome 1 and 2 years after ACL reconstruction is satisfactory in the present study and on a par with the results presented in the literature. However,when using more demanding criteria for a successful muscle function outcome, using batteries of tests or increasing the acceptable LSI level from ≥ 90% to ≥ 95%or ≥ 100%, the results are considered to be poor. It is suggested that this should be taken into consideration when presenting results after ACL rehabilitation, deciding on the criteria for a safe return to sports, or designing rehabilitation programmes after ACL reconstruction., Level of Evidence: Prognostic prospective cohort study, Level I.

Purpose: Studies have reported that knee kinematics and rotational laxity are not restored to native levels following traditional anterior cruciate ligament (ACL) reconstruction. This has led to the development of anatomic ACL reconstruction, which aims to restore native knee kinematics and long-term knee health by replicating normal anatomy as much as possible. The purpose of this review is to give an overview of current dynamic knee laxity measurement devices with the purpose of investigating the significance of dynamic laxity measurement of the knee. Gait analysis is not included., Methods: The subject was discussed with experts in the field in order to perform a level V review. MEDLINE was searched according to the discussions for relevant articles using multiple different search terms. All found abstracts were read and scanned for relevance to the subject. The reference lists of the relevant articles were searched for additional articles related to the subject., Results: There are a variety of techniques reported to measure dynamic laxity of the knee. Technical development of methods is one important part toward better understanding of knee kinematics. Validation of devices has shown to be difficult due to the lack of gold standard. Different studies use various methods to examine different components of dynamic laxity, which makes comparisons between studies challenging., Conclusion: Several devices can be used to evaluate dynamic laxity of the knee. At the present time, the devices are continuously under development. Future implementation should include primary basic research, including validation and reliability testing, as well as part of individualized surgery and clinical follow-up., Level of Evidence: Diagnostic study, Level V.

Unlabelled: The goal of anterior cruciate ligament (ACL) reconstruction surgery is to eliminate the pivot shift phenomenon. Different injury mechanisms and injury patterns may lead to specific knee laxity patterns. Computer navigation is helpful for the surgeon during examination under anesthesia. Surgical treatment may have to be altered if high-grade laxity is detected preoperatively for example by utilizing a computer navigation that is a helpful adjunct for surgeons during examination under anesthesia. A typical case for revision ACL reconstruction is presented. This article describes several techniques of laxity assessments. Based on the type and degree of pathologic laxity, a treatment algorithm has been developed., Level of Evidence: V.

Purpose: One of the templates in the development of "anatomic" anterior cruciate ligament (ACL) reconstruction has been basic science studies focusing on comparing various aspects of ACL reconstruction in order to optimize surgical technique. However, often such papers lack necessary data in the methods section to ascertain the proposed surgical technique as anatomic. The goal of this systematic review was to evaluate basic science studies on anatomic ACL reconstruction., Methods: A systematic electronic search was performed using the MEDLINE and EMBASE databases. Studies that were published from January 1995 to April 2009 were included. Only basic science studies on human cadavers that reported "anatomic" ACL reconstruction and written in English were included. Variation in surgical technique and reporting of surgical description were assessed., Results: Eighteen studies were included in this systematic review. Only the fixation method, graft type and tension pattern were reported in the majority studies. Notchplasty and radiographic documentation were grossly underreported. Other surgical data were reported at best in two-thirds of the studies. There was a large variation in the reported surgical techniques among the included studies. Due to the aforementioned, it was not deemed possible to pool data of the included studies., Conclusion: For most variables in the surgical technique description, there was sizeable underreporting resulting in an inability to pool the outcomes. To provide literature that holds up to the current high level of medical research, authors are encouraged to report their surgical technique in a thorough manner, similar to high-level clinical trials.