Treatment after anterior cruciate ligament injury: Panther Symposium ACL Treatment Consensus Group

Sex-differences in psychological readiness for return-to-sport following anterior cruciate ligament reconstruction

Females are at greatest risk for reinjury after return to sport (RTS) following anterior cruciate ligament (ACL) reconstruction (ACLR). The reasons for these sex differences, however, remain unclear. Psychological factors such as kinesiophobia have been identified as a potential predictor for reinjury following RTS. Studies investigating kinesiophobia have identified sex differences, yet whether this holds in the ACLR population remains unknown. The purpose of this study was to examine whether there are sex differences in kinesiophobia and other psychological factors, such as readiness to RTS and self-reported pain in the ACLR population. A total of 20 participants, eleven males (23.0 ± 8.4 years, 178.9 ± 7.6 cm, 76.8 ± 10.4 kg) and 9 females (19.6 ± 5.3 years, 165.1 ± 4.0 cm, 73.2 ± 25.0 kg) voluntarily participated in this study. The Tampa Scale for Kinesiophobia (TSK-11), Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) scale, and self-reported pain using a visual analog scale (VAS) were administered after clearance for RTS (10.5 ± 2.3 months post-ACLR). Statistical significance was set a priori at p<0.05. A significant difference between sexes was observed for the ACL-RSI with males reporting a significantly higher score (92.82±16.16) compared to females (77.0±15.54; p = 0.040). There were no significant differences between sexes for VAS for pain (males = 4.55 ± 6.50; females = 1.22 ± 3.31; p = 0.228) and TSK-11 (males = 18.73 ± 3.17; females = 19.67 ± 4.61; p = 0.596). The results of this study demonstrated males had significantly higher ACL-RSI scores than females, suggesting males may have higher psychological readiness following clearance for RTS. This study did not demonstrate significant differences between sexes for kinesiophobia or pain level. Caution in interpretation of results is warranted due to the small sample size, highlighting the need for further research in this area.

Mesenchymal stem cell-derived extracellular vesicles in joint diseases: Therapeutic effects and underlying mechanisms

Joint diseases greatly impact the daily lives and occupational functioning of patients globally. However, conventional treatments for joint diseases have several limitations, such as unsatisfatory efficacy and side effects, necessitating the exploration of more efficacious therapeutic strategies. Mesenchymal stem cell (MSC)-derived EVs (MSC-EVs) have demonstrated high therapeutic efficacyin tissue repair and regeneration, with low immunogenicity and tumorigenicity. Recent studies have reported that EVs-based therapy has considerable therapeutic effects against joint diseases, including osteoarthritis, tendon and ligament injuries, femoral head osteonecrosis, and rheumatoid arthritis. Herein, we review the therapeutic potential of various types of MSC-EVs in the aforementioned joint diseases, summarise the mechanisms underlying specific biological effects of MSC-EVs, and discuss future prospects for basic research on MSC-EV-based therapeutic modalities and their clinical translation. In general, this review provides an in-depth understanding of the therapeutic effects of MSC-EVs in joint diseases, as well as the underlying mechanisms, which may be beneficial to the clinical translation of MSC-EV-based treatment. The translational potential of this article: MSC-EV-based cell-free therapy can effectively promote regeneration and tissue repair. When used to treat joint diseases, MSC-EVs have demonstrated desirable therapeutic effects in preclinical research. This review may supplement further research on MSC-EV-based treatment of joint diseases and its clinical translation.

Knowledge and awareness of anterior cruciate ligament injury among Turkish professional athletes: an online survey

The purpose of this study was to assess the awareness and knowledge of professional team sport athletes about ACL injuries, injury prevention programs, and the return to sports after ACL injuries. A total of 419 athletes representing soccer, basketball, volleyball and handball sports were included in the study. We utilized a 15-item self-report survey to assess the awareness of athletes about ACL injury, ACL injury prevention program, and return to sport after ACL injuries. Male and soccer players participated in prevention programs more than female athletes (p = 0.001). Participation in prevention programs was significantly higher in the ≥ 18 years old group than in the < 18 years old group (p = 0.040). Participants who were informed about ACL injuries were 8.4 times more likely to participate in the ACL injuries prevention program than others (OR: 8.38, 95% CI: 3.823-18.376, p < 0.001). The majority of participants believed that return to sport after ACL injury takes 6 months and 81.4% of them thought that it is not possible to do sport without an ACL. This study revealed that the awareness and performance of ACL prevention training programs among professional team sport athletes were insufficient. The athletes' knowledge regarding return to sports after ACL injuries was also inadequate. Improving athletes' knowledge of ACL injuries may lead to increased participation in ACL injury prevention programs. Thus, the provision of tailored educational interventions to athletes could potentially enhance their awareness and understanding of ACL injuries, consequently contributing towards the prevention of such injuries.

Decreasing Incidence of Anterior Cruciate Ligament Tears, Increasing Utilization of Anterior Cruciate Ligament Reconstruction in the United States from 2010-2020

PURPOSE

The present study aimed to characterize the incidence of anterior cruciate ligament (ACL) tears, ACL reconstruction (ACLR), and ACL non-operative management from 2010-2020, stratifying by age, biological sex, and Charlson Comorbidity Index (CCI) score.

METHODS

A retrospective cohort analysis was performed using the PearlDiver national insurance claims database. Cohorts of patients with ACL tears, ACLR, and non-operative management were identified using ICD-9/10, and CPT codes between 2010-2020. All patients with ACL tears were included. Patients were stratified by age, sex, and CCI. Compound Annual Growth Rate (CAGR) analysis, T tests, and Cohen's d tests were performed to analyze trends and demographic variables.

RESULTS

Of 931,186 ACL tears during the study period, 196,589 were managed with ACLR and 734,597 were managed non-operatively. The cumulative incidence of ACL tears was 75.19 tears per 100,000 person-years. There was a modest decrease in the incidence of ACL tears, ACLR, and non-operative management from 2010-2020, with CAGRs of -3.43%, -3.55%, and -5.35%, respectively. The relative utilization of ACLR compared to non-operative management increased from 2010-2020 (CAGR 2.15%). Patients aged 10-19 accounted for the majority of ACL tears (22.31%) and ACLRs (30.97%). A slight majority of ACL tears (51.2%, p<0.001), ACLR (50.7%, p<0.001), and ACL tears with non-operative management (51.6%, p<0.001) occurred in female patients. The mean CCI of patients who underwent ACLR (mean=0.32; SD=0.77) was significantly lower than that of the general ACL tear cohort (mean=0.54; SD=1.19; p=0.005), and the non-operative management cohort (mean=0.64; SD 1.32; p=0.0004).

CONCLUSION

The overall decrease in ACL tears, ACLR, and non-operative management found in this study is a reversal from trends reported in the literature from previous decades.

LEVEL OF EVIDENCE

4 (Retrospective Case Series).

Demographic and Injury Characteristics as Potential Risk Factors for Anterior Cruciate Ligament Injuries: A Multicentric Cross-Sectional Study

Background: Anterior cruciate ligament (ACL) injuries are prevalent and can have debilitating consequences, with various factors potentially influencing their occurrence. This multicentric study aimed to comprehensively analyze the epidemiological characteristics of ACL injuries. We hypothesized that specific patient characteristics, such as age, sex, body mass index (BMI), and sports involvement, would be associated with distinct injury patterns and risk profiles. Methods: This cross-sectional study analyzed the medical records of 712 patients aged 15-60 diagnosed with ACL rupture. Data on demographics, injury mechanisms, associated injuries, graft type, and sports involvement were collected. Results: The majority of patients were male (93.1%), aged 15-30 years (80.2%), and overweight (66.7%). Autografts were the predominant graft choice (96.07%). Associated injuries were present in 79.5% of cases, with medial meniscus ruptures being the most common (37.36%). Sports-related (49.3%) and non-sports-related (50.7%) injuries were nearly equal, with non-contact injuries more prevalent (71.1%). In the sports-related subgroup, associated injuries emerged as a significant risk factor for ACL rupture (p = 0.014, OR = 1.596, 95% CI: 1.101-2.314), whereas non-contact mechanisms showed borderline significance (OR = 0.75, p = 0.09). Moreover, younger athletes were more susceptible to sports-related injuries (p = 0.024), with football being the primary sport involved. Conclusions: This study identified a high prevalence of concomitant injuries with ACL injury, which increased the risk of ACL injury, particularly in sports-related cases. Age-related differences in injury patterns highlight the need for age-appropriate preventive measures, especially for younger athletes participating in high-risk sports. This underscores the need for comprehensive injury assessment, targeted prevention strategies, and optimized clinical management approaches tailored to different populations' specific characteristics and risks.

All-Inside Anterior Cruciate Ligament Reconstruction Had Clinical Outcome Similar to the Transtibial Technique Except for Improved Side-to-Side Difference and Tegner Activity Scale: A Systematic Review and Meta-analysis

PURPOSE

To compare clinical outcomes of the all-inside technique with the transtibial technique in anterior cruciate ligament reconstruction based on available literature on this topic.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist, we conducted a systematic search for randomized controlled trials and cohort studies. Our comprehensive search encompassed PubMed, Embase, Cochrane Library, and Web of Science. We included randomized controlled trials (RCTs) and cohort studies that compared the 2 techniques with a minimal 1-year follow-up. Two independent authors assessed RCTs using the risk of bias tool developed by the Cochrane Collaboration and evaluated the quality of cohort studies using the Newcastle-Ottawa Scale for Assessing the Quality of Nonrandomized Comparative Trials. The subjective and objective outcomes, complications, and graft failure were obtained. R software was used to perform the analysis.

RESULTS

The present analysis enrolled 9 RCTs (n = 687) and 11 cohort studies (n = 910). After a minimal 1-year follow-up in RCTs, functional outcomes such as International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity scale, Knee Society Score, and hop test were found to be similar between 2 techniques. The laxity outcomes, including the IKDC objective grade and pivot-shift test, were suggested to be comparable. There was a significant difference favoring the transtibial technique in terms of side-to-side difference (P = .04; 95% confidence interval [CI], 0.08-0.90). The pooled data from cohort studies indicated equivalent results in terms of IKDC subjective score, Lysholm score, side-to-side difference, IKDC objective grade, complications, and graft failure, with the exception of statistical difference in the Tegner activity scale (P = .03; 95% CI, -0.50 to -0.04).

CONCLUSIONS

Our findings suggest that there is no difference in most outcome scores between the all-inside and transtibial techniques for anterior cruciate ligament reconstruction. There are statistically significant differences in side-to-side difference and Tegner activity scale favoring the all-inside technique.

LEVEL OF EVIDENCE

Level IV, meta-analysis of Level I to IV studies.

Relationship Between Revision Rate, Osteoarthritis, and Obesity for ACL Reconstruction: A Nationwide Retrospective Cohort Study

Background

The long-term goal of anterior cruciate ligament (ACL) reconstruction is to prevent secondary osteoarthritis due to instability. Obesity itself is also a risk factor for osteoarthritis and shows an increase in its incidence, but little is known about the relationship between obesity and the outcome of ACL reconstruction.

Purpose/Hypothesis

This study aimed to determine the relationship between the outcome of ACL reconstruction and obesity. It was hypothesized that obesity would be associated with the revision rate of ACL reconstruction and additional surgical treatment for osteoarthritis in patients who undergo ACL reconstruction.

Study design

Cohort study; Level of evidence, 3.

Methods

Claims and health screening data of the National Health Insurance Service were used to analyze patients who underwent ACL reconstruction between January 1, 2003, and December 31, 2021. The association between obesity and risk of revision ACL reconstruction and additional surgical treatment for osteoarthritis or meniscal lesion was analyzed. Body mass index (BMI) was used to classify patients as underweight (BMI, <18.5), normal weight (BMI, 18.5-24.9), overweight (BMI, 25.0-29.9), obese (BMI, 30.0-39.9), or morbidly obese (BMI, ≥40.0). Multivariable Cox proportional hazards model analysis was conducted.

Results

A total of 56,734 patients were included. Of them, 311 (0.5%) patients were underweight, 26,613 (46.9%) were normal weight, 24,372 (43.0%) were overweight, 5324 (9.4%) were obese, and 114 (0.2%) patients were morbidly obese. The underweight group showed a significantly lower risk of revision ACL reconstruction than the normal weight group (hazard ratio [HR], 0.54; 95% CI, 0.31-0.93; P = .0273). However, the overweight, obese, and morbidly obese groups had no significant difference from the normal weight group. The risk of high tibial osteotomy (HTO) or total knee arthroplasty (TKA) was significantly high for the overweight (HR, 1.93; 95% CI, 1.70-2.19; P < .0001) and obese (HR, 2.71; 95% CI, 2.23-3.30; P < .0001) groups. Subgroup analysis performed in patients ≥40 years of age for the risk of HTO showed a significant increased risk in the overweight group (HR, 1.889; 95% CI, 1.56-2.29; P < .0001) and obese group (HR, 2.78; 95% CI, 2.10-3.69; P < .0001). Subgroup analysis performed in patients ≥50 years of age for the risk of TKA also showed a significant increased risk in the overweight group (HR, 2.03; 95% CI, 1.67-2.47; P < .0001) and obese group (HR, 2.53; 95% CI, 1.83-3.50; P < .0001). After adjusting for meniscal injury at index surgery by multivariate regression analysis, 1.87- and 2.75-fold increased risks of HTO were identified for the overweight and obese groups, respectively, for patients aged >40 years. For patients aged >50 years, 2.02-fold and 2.52-fold increased risks of TKA were observed for the overweight and obese groups, respectively. The risk of additional surgery due to the meniscal lesion was high for the overweight (HR, 1.09; 95% CI, 1.03-1.15; P = .002) and obese (HR, 1.10; 95% CI, 1.01-1.21; P = .0351) groups, while no significant difference was found for the underweight and morbidly obese groups.

Conclusion

This study highlights that obesity does not increase the revision rate of ACL reconstruction. However, the risk of additional surgical treatment for osteoarthritis and meniscal lesions increased as BMI increased. Further investigation is needed to determine the efficacy of ACL reconstruction for preventing osteoarthritis in obese patients.

Nonoperative Anterior Cruciate Ligament Injury Treatment

This article outlines the key points in the nonoperative treatment of an anterior cruciate ligament (ACL) injury. Initial evaluation and treatment of an acute knee injury, often performed by a physician with limited experience in the treatment of an ACL injury, follow the basic diagnostic workup that lead to the diagnosis. The principles of rehabilitation after ACL injury have changed from time based to criteria based, and the different phases based on physical criteria are described.

Does Combined Reconstruction of the Medial Collateral and Anterior Cruciate Ligaments Provide Better Knee Function? A Systematic Review and Meta-Analysis

Objective: This study aimed to determine if medial collateral ligament reconstruction (MCLR) alongside anterior cruciate ligament reconstruction (ACLR) preserves knee functionality better than isolated ACLR in combined ACL and MCL tears. Methods: MEDLINE, EMBASE, Scopus, CENTRAL, and Web of Science were searched systematically on 31 March 2023. Studies reporting post-operative function after ACLR and ACLR + MCLR in combined injuries were included. Outcomes included International Knee Documentation Committee (IKDC) score, side-to-side difference (SSD), Lysholm, and Tegner scale values. Results: Out of 2362 papers, 8 studies met the criteria. The analysis found no significant difference in outcomes (MD = 3.63, 95% CI: [-5.05, 12.3] for IKDC; MD = -0.64, 95% CI: [-3.24, 1.96] for SSD at 0° extension; MD = -1.79, 95% CI: [-4.61, 1.04] for SSD at 30° extension; MD = -1.48, 95% CI: [-16.35, 13.39] for Lysholm scale; MD = -0.21, 95% CI: [-4.29, 3.87] for Tegner scale) between treatments. Conclusions: This meta-analysis found no significant difference in outcomes between ACLR and ACLR + MCLR, suggesting that adding MCLR does not provide additional benefits. Due to the heterogeneity and quality of the included studies, further high-quality randomized controlled trials are needed to determine the optimal treatment for combined severe MCL-ACL injuries.

Rehabilitation and Return to Sport After Anterior Cruciate Ligament Reconstruction

Rehabilitation after an anterior cruciate ligament (ACL) reconstruction requires patience, devotion, and discipline. Rehabilitation should be individualized to each patient's specific need and sport. Return to sport is a continuum throughout the rehabilitation, and patients should not return to performance before passing a battery of muscle function tests and patient-reported outcomes, as well as change of direction-specific tests. Return to full participation should be an agreement between the patient, physical therapist, surgeon, and coach. For minimal risk for second ACL injury, patients should continue with maintenance and prevention training even after returning to sport.

Lateral femoral tunnel preparation and graft fixation for anterior cruciate ligament reconstruction-A discussion

This article provides a discussion and commentary around the recent advances in arthroscopic anterior cruciate ligament reconstruction (ACLR), with a focus on the aspects of lateral femoral tunnel preparation and graft fixation techniques. The paper explores and comments on a recently published review by Dai et al, titled "Research progress on preparation of lateral femoral tunnel and graft fixation in ACLR", while providing insight into its relevance within the field of ACLR, and recommendations for future research.

Good clinical outcomes of anterior cruciate ligament reconstruction in patients over 60 years of age

PURPOSE

To evaluate the clinical outcomes following arthroscopic anterior cruciate ligament (ACL) reconstruction (ACLR) in patients over 60 years and to investigate the potential impact of preoperative osteoarthritis (OA) on these outcomes.

METHODS

A retrospective study included ACL-injured patients over 60 years who underwent primary arthroscopic ACLR between 2010 and 2020. The Lysholm score and the International Knee Documentation Committee (IKDC) score were assessed preoperatively and at the final follow-up. The Tegner activity scale was performed to evaluate patients' activity levels. Data on return to sports, patient satisfaction, subsequent injuries and complications were collected. Preoperative radiographs were used to grade OA according to the Kellgrene-Lawrence classification. Correlation analysis between OA and clinical outcomes was performed. The rates of achieving the minimal clinically significant difference and patient-acceptable symptoms state were documented.

RESULTS

A total of 37 patients were included in this study. The mean age at surgery was 62.3 ± 2.3 years, with a mean follow-up of 6.3 ± 3.2 years (range: 2.1-12.4). Patients showed statistically significant (all p < 0.001) improvements in the mean IKDC (38.9 ± 9.4-66.8 ± 12.5), Lysholm (48.8 ± 15.4-83.0 ± 12.8) and Tegner (1-3) scores. Fourteen patients (37.8%) returned to sports. No correlation was observed between the degree of preoperative OA and clinical outcomes (n.s.).

CONCLUSION

Patients over 60 years with symptomatic ACL-deficient knees could benefit from ACLR, even when mild to moderate OA is present preoperatively.

LEVEL OF EVIDENCE

Level IV.

Shared decision-making with athletes: a survey study of healthcare professionals' perspectives

Objectives

Shared decision-making (SDM) is a trending topic in athlete health care; however, little is known about its use in a sports context. This study aimed to measure knowledge and self-perceived practice of SDM among healthcare professionals working with athletes. This study evaluates SDM attitudes and preferences and explores how healthcare professionals perceive the factors influencing SDM.

Methods

A web-based cross-sectional survey with open-ended and closed-ended questions.

Results

Our survey was completed by 131 healthcare professionals. The majority (63.6%) reported to prefer SDM and to be confident in their SDM skills (81.1%). Despite this inclination and confidence, only one in four clinicians reported consistent practice of SDM when feasible. Additionally, most clinicians lacked SDM knowledge. The barriers perceived by healthcare professionals included time constraints (17.6%), limited patient knowledge (17.6%), limited patient motivation (13.5%) and language barriers (16.2%). Importantly, two-thirds of the participants believed that SDM in athlete health care differs from SDM in non-athletes due to the high-pressure environment, the tension between performance and health, and the involvement of multiple stakeholders with potentially conflicting interests.

Conclusions

Although healthcare professionals preferred SDM, they did not fully understand nor routinely practice it. Most healthcare professionals perceive SDM in athlete health care to differ from SDM in the general population. Therefore, to inform the implementation of SDM in athlete health care, future research is crucial to understand better what makes practising SDM unique in this setting.

Comparison of knee flexor strength recovery between semitendinosus alone versus semitendinosus with gracilis autograft for ACL reconstruction: a systematic review and meta-analysis

BACKGROUND

Whether there is a difference in harvesting the semitendinosus tendon alone (S) or in combination with the gracilis tendon (SG) for the recovery of knee flexor strength after anterior cruciate ligament (ACL) reconstruction remains inconclusive. Therefore, this study aimed to assess the recovery of knee flexor strength based on the autograft composition, S or SG autograft at 6, 12, and ≥ 24 months after ACL reconstruction.

METHODS

A systematic review and meta-analysis was conducted following the PRISMA guidelines. A comprehensive search was performed encompassing the Cochrane Library, Embase, Medline, PEDRo and AMED databases from inception to January 2023. Inclusion criteria were human clinical trials published in English, comprised of randomized controlled trials (RCTs), longitudinal cohort-, cross-sectional and case-control studies that compared knee flexor strength recovery between S and SG autografts in patients undergoing primary ACL reconstruction. Isokinetic peak torques were summarized for angular velocities of 60°/s, 180°/s, and across all angular velocities, assessed at 6, 12, and ≥ 24 months after ACL reconstruction. A random-effects model was used with standardized mean differences and 95% confidence intervals. Risk of bias was assessed with the RoBANS for non-randomized studies and the Cochrane RoB 2 tool for RCTs. Certainty of evidence was appraised using the GRADE working group methodology.

RESULTS

Among the 1,227 patients from the 15 included studies, 604 patients received treatment with S autograft (49%), and 623 received SG autograft (51%). Patients treated with S autograft displayed lesser strength deficits at 6 months across all angular velocities d = -0.25, (95% CI -0.40; -0.10, p = 0.001). Beyond 6 months after ACL reconstruction, no significant difference was observed between autograft compositions.

CONCLUSION

The harvest of S autograft for ACL reconstruction yields superior knee flexor strength recovery compared to SG autograft 6 months after ACL reconstruction, irrespective of angular velocity at isokinetic testing. However, the clinical significance of the observed difference in knee flexor strength between autograft compositions at 6 months is questionable, given the very low certainty of evidence and small effect size. There was no significant difference in knee flexor strength recovery between autograft compositions beyond 6 months after ACL reconstruction.

TRIAL REGISTRATION

CRD42022286773.

Management after acute injury of the anterior cruciate ligament (ACL). Part 3: Recommendation on surgical treatment

PURPOSE

The aim of this consensus project was to give recommendations regarding surgical treatment of the anterior cruciate ligament (ACL) injured patient.

METHODS

For this consensus process, an expert, steering and rating group was formed. In an initial online meeting, the steering group, together with the expert group, formed various key topic complexes for which multiple questions were formulated. For each key topic, a structured literature search was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Sufficient consensus was defined as 80% agreement.

RESULTS

During this consensus process, 30 topics regarding the surgical management and technique of ACL reconstruction were identified. The literature search for each key question resulted in 30 final statements. Of these 30 final statements, all achieved consensus.

CONCLUSIONS

This consensus process has shown that surgical treatment of ACL injury is a complex process. Various surgical factors influence patient outcomes. The proposed treatment algorithm can be used as a decision aid for the surgeon.

LEVEL OF EVIDENCE

Level V.

Restoring Knee Flexor Strength Symmetry Requires 2 Years After ACL Reconstruction, But Does It Matter for Second ACL Injuries? A Systematic Review and Meta-analysis

BACKGROUND

It is unknown whether knee flexor strength recovers after anterior cruciate ligament (ACL) reconstruction with a hamstring tendon (HT) autograft and whether persistent knee flexor strength asymmetry is associated to a second ACL injury.

OBJECTIVE

We aimed to systematically review (1) whether knee flexor strength recovers after ACL reconstruction with HT autografts, and (2) whether it influences the association with a second ACL injury. A third aim was to summarize the methodology used to assess knee flexor strength.

DESIGN

Systematic review and meta-analysis reported according to PRISMA.

METHODS

A systematic search was performed using the Cochrane Library, Embase, Medline, PEDRo, and AMED databases from inception to December 2021 and until completion in January 2023. Human clinical trials written in English and conducted as randomized controlled trials, longitudinal cohort, cross-sectional, and case-control studies on patients with index ACL reconstructions with HT autografts harvested from the ipsilateral side were considered. Knee flexor strength was measured isokinetically in both the reconstructed and uninjured limb to enable the calculation of the limb symmetry index (LSI). The Risk of Bias Assessment Tool for Non-Randomized Studies was used to assess risk of bias for non-randomized studies and the revised Cochrane Risk of Bias tool was used for randomized controlled trials. For the meta-analysis, the LSI (mean ± standard error) for concentric knee flexor strength at angular velocities of 60°/second (s) and 180°/s preoperatively and at 3 months, 6 months, 12 months, and 24 months were pooled as weighted means with standard errors.

RESULTS

The search yielded 64 studies with a total of 8378 patients, which were included for the assessment of recovery of knee flexor strength LSI, and a total of 610 patients from four studies that investigated the association between knee flexor strength and second ACL injuries. At 1 year after ACL reconstruction, the knee flexor strength LSI had recovered to 89.0% (95% CI 87.3; 90.7%) and 88.3% (95% CI 85.5; 91.1%) for the velocities of 60°/s and 180°/s, respectively. At 2 years, the LSI was 91.7% (95% CI 90.8; 92.6%) and 91.2% (95% CI 88.1; 94.2%), for velocities of 60°/s and 180°/s, respectively. For the association between knee flexor strength and second ACL injuries, there was insufficient and contradictory data.

CONCLUSIONS

There was low to very low certainty of evidence indicating that the recovery of knee flexor strength LSI, defined as ≥ 90% of the uninjured side, takes up to 2 years after ACL reconstruction with HT autografts. Whether knee flexor strength deficits influence the association of second ACL injuries is still uncertain. There was considerable heterogeneity in the methodology used for knee flexor strength assessment, which together with the low to very low certainty of evidence, warrants further caution in the interpretation of our results.

REGISTRATION NUMBER

CRD42022286773.

Comparison of Clinical Outcomes Between Modern Augmented ACL Repair and Autograft ACL Reconstruction: A Systematic Review and Meta-analysis of Studies With Minimum 2-Year Follow-up

Background

Anterior cruciate ligament (ACL) reconstruction has been the gold standard for primary ACL rupture since the 1990s. In the past decade, ACL repair has received renewed attention and increased research.

Purpose

To compare the clinical outcomes of modern augmented ACL repair versus autograft reconstruction for ACL ruptures.

Study Design

Systematic review; Level of evidence, 3.

Methods

A search of the PubMed, EMBASE, Scopus, Web of Science, and the Cochrane Library databases was conducted for prospective or retrospective comparative studies published between January 1, 2010, and January 3, 2023, with a minimum 2-year follow-up. Two independent reviewers performed data extraction and methodological quality assessment. Sensitivity analysis was performed to maintain the stability of results.

Results

Nine studies were included (minimum follow-up period, 24-60 months). The total sample size was 833 patients (augmented repair group: 358 patients; autograft ACL reconstruction group: 475 patients). There were 4 randomized controlled trials (level 1), 1 prospective comparative study (level 2), 2 retrospective comparative studies (level 3), and 2 case-control studies (level 3). The augmented ACL repair group attained significantly higher Lysholm score (weighted mean difference [WMD] = 1.57; 95% confidence interval [CI], 0.14-3.01; P = .03) and hamstring strength (WMD = 36.69; 95% CI, 29.07-44.31; P < .01) but had higher rates of hardware removal (odds ratio [OR] = 6.30; 95% CI, 2.44-16.23; P = .0001), reoperation (OR = 1.87; 95% CI, 1.33-2.62; P = .0003), and failure (OR = 1.58; 95% CI, 1.03-2.43; P = .0003) compared with the autograft ACL reconstruction group. No significant differences were observed between the repair and reconstruction groups regarding postoperative International Knee Documentation Committee scores, Tegner scores, knee laxity, satisfaction, ACL revisions, complications, and reoperation rather than revision.

Conclusion

Augmented ACL repair was associated with higher rates of reoperation, hardware removal, and failure compared with autograft ACL reconstruction in studies with minimum 2-year follow-up data. However, augmented ACL repair had higher Lysholm scores and hamstring strength versus autograft ACL reconstruction.

Correlation between hip muscle strength and the lower quarter Y-balance test in athletes following anterior cruciate ligament reconstruction

INTRODUCTION

The lower quarter Y-balance test (YBT-LQ), which measures dynamic postural control, has been reported to be predictive of lower limb injuries in athletes. It requires subjects to control their body while maintaining a single-leg stance, which necessitates sufficient strength of the hip muscles to maintain stability. The purpose of the study was to investigate the correlation between the performance of the YBT-LQ and the hip abductor or extensor muscle strength in athletes following anterior cruciate ligament reconstruction surgery (ACLR).

METHODS

Fifteen athletes with post-ACLR participated in this cross-sectional study. The participants completed the YBT-LQ, followed by isokinetic measurement of the hip abductor and extensor muscles of both the legs. The peak and average torque of the hip abductor and extensor muscles were tallied with the composite score of the YBT-LQ for each limb.

RESULTS

No correlation was found between the strength of the hip muscles and the YBT-LQ composite score in both injured and non-injured limbs at all velocities except for the eccentric hip abductor and concentric hip extensor torques. The eccentric hip abductor average torque is strongly associated with the YBT-LQ (r = 0.663, p = 0.010) at a speed of 180°/s. The concentric hip extensor peak torque was weakly correlated with balance (r = 0.540, p = 0.046) at a speed of 180°/s.

CONCLUSION

Our study demonstrated a positive correlation between the YBT-LQ and eccentric hip abduction and concentric hip extension at higher velocities. This shows the importance of implementing velocity-oriented rehabilitation in an athletic population following ACLR.

There is no difference in the efficacy of anterior cruciate ligament reconstruction using autograft combined with or without ligament augmentation: a systematic review and meta-analysis

PURPOSE

This study aims to determine the efficacy of anterior cruciate ligament reconstruction (ACLR) using autograft combined with or without ligament augmentation.

METHODS

A computerized search of the databases was conducted, including PubMed, Web of Science, Embase, Scopus and the Cochrane Library. Only prospective or retrospective comparative studies with a minimum 2-year follow-up were considered for inclusion. Two independent reviewers performed data extraction and methodological quality assessment. A Mantel-Haenszel analysis was used for the pooling of results. Sensitivity analysis was performed to maintain the stability of results. The egger test was applied to assess the publication bias.

RESULTS

Fourteen studies were included. The total cohort was 1353 patients (non-augmented group: 763 patients; augmented group: 590 patients). There were three Randomized Controlled Trials (RCTs, Level I), six retrospective comparative studies (Level III) and five case-control studies (Level III). The follow-up rate was ≥ 88% and the follow-up periods were ≥ 24 months in all included studies. The augmented graft used to compare with autograft included the Ligament Augmentation Device (LAD), the Ligament Advanced Reinforcement System (LARS) artificial ligament, FiberTape, hamstring tendon allograft, degradable poly (urethane urea). No significant differences were observed between the augmented and non-augmented groups regarding postoperative patient-reported outcomes (PROs), including the International Knee Documentation Committee score, Lysholm score and Tegner score, knee laxity, including KT-1000, side-to-side difference, Lachman test and pivot shift and rate of graft failure.

CONCLUSIONS

ACLR using autografts combined with ligament augmentation shows no advantages in PROs, knee laxity and graft failure rate compared with using autografts only.

LEVEL OF EVIDENCE

Level III.

TRIAL REGISTRATION

The research protocol was registered at the PROSPERO database (CRD42022324784).

How to predict the dimensions of anterior cruciate ligament in children based on MRI?

There are many studies examining the dimensions of the anterior cruciate ligament (ACL) in children. The correlations between the ACL size in children and other parameters are not well understood. To detect the correlations between the ACL size in children and other parameters including age, gender, bone and soft tissue parameters through measurements on MRI images, and to establish prediction models for the ACL size. A total of 99 patients who underwent MRI scan were included (39 girls, 60 boys; mean age, 13.01 ± 3.94; range of age, 4 to 18). The following measurements were taken on MRI images by 2 observers: ACL length, ACL width, posterior cruciate ligament (PCL) length, the distance from the most anterior aspect of the tibial epiphysis to the anterior aspect of the ACL tibial insertion (AATI), the distance from the most anterior aspect of the tibial epiphysis to the posterior aspect of the ACL tibial insertion (APTI), and the tibial anteroposterior diameter (AP). Correlations between these measurements and the patients' gender and age were investigated, and univariate and multiple linear regression models were established accordingly. Before 13 years old, the ACL length was significantly correlated with the tibial anteroposterior diameter and age (R2 = 0.872, P < .001), and there were no statistically significant gender differences. After 13 years old, the ACL length was significantly correlated with the PCL length and APTI in males (R2 = 0.443, P < .001), and with the PCL length in females (R2 = 0.443, P < .001). In children under 13 years old, there was no significant gender difference in ACL length, and the tibial anteroposterior diameter and age were found to be important indicators in assessing the ACL size. After 13 years old, a significant gender difference in ACL length was observed, and the ACL length was found to be weakly correlated with age and bone parameters. In order to accurately evaluate the ACL size in children aged 13 years and above, it is necessary to refer to the dimensions of the ACL on the collateral side.

Management of anterior cruciate ligament tears in Tanner stage 1 and 2 children: a narrative review and treatment algorithm guided by ACL tear location

The incidence of anterior cruciate ligament (ACL) tears in skeletally immature patients has acutely increased over the last 20 years, yet there is no consensus on a single "best treatment." Selection of an optimal treatment is critical and based on individual circumstances; consequently, we propose a treatment-selection algorithm based on skeletal development, ACL tear location, type, and quality, as well as parental perspective in order to facilitate the decision-making process. We combined our surgical group's extensive case histories of ACL tear management in Tanner Stage 1 and 2 patients with those in the literature to form a consolidated data base. For each case the diagnostic phase, communication with patient and parents, treatment choice(s), selected surgical techniques and rehabilitation schedule were critically analyzed and compared for patient outcomes. MRI-imaging and intraoperative tissue quality assessment were preeminent in importance for selection of the optimal treatment strategy. Considerations for selecting an optimal treatment included: associated lesions, the child/patient and parent(s)' well-informed and counseled consent, biological potential, and the potential for successful ACL preservative surgery. Complete ACL tears were evaluated according to tear-location. In type I and II ACL tears with remaining good tissue quality, we propose primary ACL repair. In type III and IV ACL tears we propose physeal-sparing reconstruction with an iliotibial band graft. Finally, in the case of a type V ACL tear, we propose that the best treatment be based on the Meyers-McKeever classification. We present a facile decision-making algorithm for ACL management in pediatric patients based on specific elements of tissue damage and status.

Management of anterior cruciate ligament revision in adults: the 2022 ESSKA consensus part III-indications for different clinical scenarios using the RAND/UCLA appropriateness method

PURPOSE

The aim of the ESSKA 2022 consensus Part III was to develop patient-focused, contemporary, evidence-based, guidelines on the indications for revision anterior cruciate ligament surgery (ACLRev).

METHODS

The RAND/UCLA Appropriateness Method (RAM) was used to provide recommendations on the appropriateness of surgical treatment versus conservative treatment in different clinical scenarios based on current scientific evidence in conjunction with expert opinion. A core panel defined the clinical scenarios with a moderator and then guided a panel of 17 voting experts through the RAM tasks. Through a two-step voting process, the panel established a consensus as to the appropriateness of ACLRev for each scenario based on a nine-point Likert scale (in which a score in the range 1-3 was considered 'inappropriate', 4-6 'uncertain', and 7-9 'appropriate').

RESULTS

The criteria used to define the scenarios were: age (18-35 years vs 36-50 years vs 51-60 years), sports activity and expectation (Tegner 0-3 vs 4-6 vs 7-10), instability symptoms (yes vs no), meniscus status (functional vs repairable vs non-functional meniscus), and osteoarthritis (OA) (Kellgren-Lawrence [KL] grade 0-I-II vs grade III). Based on these variables, a set of 108 clinical scenarios was developed. ACLRev was considered appropriate in 58%, inappropriate in 12% (meaning conservative treatment is indicated), and uncertain in 30%. Experts considered ACLRev appropriate for patients with instability symptoms, aged ≤ 50 years, regardless of sports activity level, meniscus status, and OA grade. Results were much more controversial in patients without instability symptoms, while higher inappropriateness was related to scenarios with older age (51-60 years), low sporting expectation, non-functional meniscus, and knee OA (KL III).

CONCLUSION

This expert consensus establishes guidelines as to the appropriateness of ACLRev based on defined criteria and provides a useful reference for clinical practice in determining treatment indications.

LEVEL OF EVIDENCE

II.

Prevalence of post-traumatic osteoarthritis after anterior cruciate ligament injury remains high despite advances in surgical techniques

Aims

The aim of this study was to report the pooled prevalence of post-traumatic osteoarthritis (PTOA) and examine whether the risk of developing PTOA after anterior cruciate ligament (ACL) injury has decreased in recent decades.

Methods

The PubMed and Web of Science databases were searched from 1 January 1980 to 11 May 2022. Patient series, observational studies, and clinical trials having reported the prevalence of radiologically confirmed PTOA after ACL injury, with at least a ten-year follow-up, were included. All studies were analyzed simultaneously, and separate analyses of the operative and nonoperative knees were performed. The prevalence of PTOA was calculated separately for each study, and pooled prevalence was reported with 95% confidence intervals (CIs) using either a fixed or random effects model. To examine the effect of the year of injury on the prevalence, a logit transformed meta-regression analysis was used with a maximum-likelihood estimator. Results from meta-regression analyses were reported with the unstandardized coefficient (β).

Results

The pooled prevalence of PTOA was 37.9% (95% CI 32.1 to 44) for operatively treated ACL injuries with a median follow-up of 14.6 years (interquartile range (IQR) 10.6 to 16.7). For nonoperatively treated ACL injuries, the prevalence was 40.5% (95% CI 28.9 to 53.3), with a median of follow-up of 15 years (IQR 11.7 to 20.0). The association between the year of operation and the prevalence of PTOA was weak and imprecise and not related to the choice of treatment (operative β -0.038 (95% CI -0.076 to 0.000) and nonoperative β -0.011 (95% CI -0.101 to 0.079)).

Conclusion

The initial injury, irrespective of management, has, by the balance of probability, resulted in PTOA within 20 years. In addition, the prevalence of PTOA has only slightly decreased during past decades. Therefore, further research is warranted to develop strategies to prevent the development of PTOA after ACL injuries.

Correlation Between the Location and Distance of Kissing Contusions and Knee Laxity in Acute Noncontact ACL Injury

BACKGROUND

Bone bruise (BB) and kissing contusion are common features of acute anterior cruciate ligament (ACL) injury on magnetic resonance imaging (MRI). The correlation between the location and distance of kissing contusions and knee laxity remains unclear.

PURPOSE

To determine the significance of different patterns of BB in acute noncontact ACL injury and assess the correlation between the location and distance of kissing contusions and the severity of knee laxity.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 205 patients with acute noncontact ACL injury undergoing arthroscopic treatment between January 2021 and May 2022 were included in this retrospective analysis. Patients were grouped according to the different patterns of BB. The type of ACL injury and concomitant injuries were analyzed on MRI and confirmed by arthroscopy. Anterior knee laxity was assessed by the Ligs digital arthrometer and stress radiography, and rotational knee laxity was assessed by the intraoperative pivot-shift test. The MRI parameters of the location and distance of kissing contusions were measured to assess their correlations with the severity of knee laxity.

RESULTS

Of the 205 patients with acute noncontact ACL injury, 38 were in the non-BB group and 167 were in the BB group, the latter including 32 with the isolated BB on the lateral tibial plateau and 135 with kissing contusions. There was no significant difference in the mean time from initial injury to MRI scan between the non-BB group and the BB group (14.34 ± 2.92 vs 15.17 ± 2.86 days; P = .109) or between the isolated BB subgroup and the kissing contusion subgroup (14.94 ± 2.92 vs 15.23 ± 2.85 days; P = .605). The side-to-side difference (SSD) in anterior knee laxity and the incidences of complete ACL injury, concomitant injuries, and high-grade pivot-shift test were significantly higher in the BB group than in the non-BB group, and in the kissing contusion subgroup compared with the isolated BB subgroup. The kissing contusion index of the lateral femoral condyle (LFC) and the sagittal distance of kissing contusions were significantly correlated with the SSD in anterior knee laxity and the grade of pivot-shift test (P < .001).

CONCLUSION

The presence of BB, in particular the appearance of kissing contusions, was related to greater knee laxity and higher incidences of complete ACL injury and concomitant injuries in acute noncontact ACL injury. For patients with kissing contusions, as the location of BB on the LFC moved forward and the distance between kissing contusions increased, anterior and rotational knee laxity became more serious.

It is time to target psychological readiness (or lack of readiness) in return to sports after Anterior Cruciate Ligament tears

Functional recovery has for long been the focus of rehabilitation after an Anterior Cruciate Ligament (ACL) injury. It is now increasingly recognized that more attention should be given to patients` mental recovery, their psychological readiness for returning to sport, after such an injury. Within this relatively new field of science, clinicians need clarity on when and how psychological factors should be monitored and how inexpedient psychological responses may be addressed during rehabilitation. In this Expert Opinion suggestions on how targeting psychological readiness may improve rehabilitation and return-to-sport evaluations are made based on current evidence-and issues in need of further clarification are addressed.

Consistent Indications and Good Outcomes Despite High Variability in Techniques for Two-Stage Revision Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To systematically review the current literature regarding the indications, techniques, and outcomes after 2-stage revision anterior cruciate ligament reconstruction (ACLR).

METHODS

A literature search was performed using SCOPUS, PubMed, Medline, and the Cochrane Central Register for Controlled Trials according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta Analyses statement. Inclusion criteria was limited to Level I-IV human studies reporting on indications, surgical techniques, imaging, and/or clinical outcomes of 2-stage revision ACLR.

RESULTS

Thirteen studies with 355 patients treated with 2-stage revision ACLR were identified. The most commonly reported indications were tunnel malposition and tunnel widening, with knee instability being the most common symptomatic indication. Tunnel diameter threshold for 2-stage reconstruction ranged from 10 to 14 mm. The most common grafts used for primary ACLR were bone-patellar tendon-bone (BPTB) autograft, hamstring graft, and LARS (polyethylene terephthalate) synthetic graft. The time elapsed from primary ACLR to the first stage surgery ranged from 1.7 years to 9.7 years, whereas the time elapsed between the first and second stage ranged from 21 weeks to 13.6 months. Six different bone grafting options were reported, with the most common being iliac crest autograft, allograft bone dowels, and allograft bone chips. During definitive reconstruction, hamstring autograft and BPTB autograft were the most commonly used grafts. Studies reporting patient-reported outcome measures showed improvement from preoperative to postoperative levels in Lysholm, Tegner, and objective International Knee and Documentation Committee scores.

CONCLUSIONS

Tunnel malpositioning and widening remain the most common indications for 2-stage revision ACLR. Bone grafting is commonly reported using iliac crest autograft and allograft bone chips and dowels, whereas hamstring autograft and BPTB autograft were the most used grafts during the second-stage definitive reconstruction. Studies showed improvements from preoperative to postoperative levels in commonly used patient reported outcomes measures.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I, III, and IV studies.

Management after acute rupture of the anterior cruciate ligament (ACL). Part 1: ACL reconstruction has a protective effect on secondary meniscus and cartilage lesions

PURPOSE

The aim of this consensus project was to validate which endogenous and exogenous factors contribute to the development of post-traumatic osteoarthritis and to what extent ACL (anterior cruciate ligament) reconstruction can prevent secondary damage to the knee joint. Based on these findings, an algorithm for the management after ACL rupture should be established.

METHODS

The consensus project was initiated by the Ligament Injuries Committee of the German Knee Society (Deutsche Kniegesellschaft, DKG). A modified Delphi process was used to answer scientific questions. This process was based on key topic complexes previously formed during an initial face-to-face meeting of the steering group with the expert group. For each key topic, a comprehensive review of available literature was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Consensus was defined a-priori as eighty percent agreement.

RESULTS

Of the 17 final statements, 15 achieved consensus, and 2 have not reached consensus. Results of the consensus were summarized in an algorithm for the management after ACL rupture (infographic/Fig. 2).

CONCLUSION

This consensus process has shown that the development of post-traumatic osteoarthritis is a complex multifactorial process. Exogenous (primary and secondary meniscus lesions) and endogenous factors (varus deformity) play a decisive role. Due to the complex interplay of these factors, an ACL reconstruction cannot always halt post-traumatic osteoarthritis of the knee. However, there is evidence that ACL reconstruction can prevent secondary joint damage such as meniscus lesions and that the success of meniscus repair is higher with simultaneous ACL reconstruction. Therefore, we recommend ACL reconstruction in case of a combined injury of the ACL and a meniscus lesion which is suitable for repair.

LEVEL OF EVIDENCE

Level V.

Neuromuscular activity of the lower-extremities during running, landing and changing-of-direction movements in individuals with anterior cruciate ligament reconstruction: a review of electromyographic studies

PURPOSE

Running, jumping/landing and cutting/change of direction (CoD) are critical components of return to sport (RTS) following anterior cruciate ligament reconstruction (ACLR), however the electromyographic (EMG) activity patterns of the operated leg during the execution of these tasks are not clear.

METHODS

A systematic review was conducted to retrieve EMG studies during running, jumping/landing and cutting/(CoD) in ACLR patients. MEDLINE, PubMed, SPORTDiscus and Web of Science databases were searched from 2000 to May, 2022 using a combination of keywords and their variations: "anterior cruciate ligament reconstruction" OR "ACLR", "electromyography" OR "EMG", "running", "jumping" OR "landing", "cutting" OR "change-of-direction" OR "CoD". The search identified studies comparing EMG data during running, landing and cutting/(CoD) between the involved limb and contralateral or control limbs. Risk of bias was assessed and quantitative analyses using effect sizes were performed.

RESULTS

Thirty two studies met the inclusion criteria. Seventy five percent (24/32) of the studies reported altered EMG activity pattern of the ACLR leg during running, jumping/landing and cutting/(CoD) when compared with either the healthy control leg or the contra-lateral leg. Twelve studies showed decreased, delayed or earlier onset and delayed peak in quadriceps EMG activity with small to large effect sizes and 9 studies showed increased, delayed or earlier onset and delayed peak in hamstrings EMG activity with small to large effect sizes. Four studies showed a "hamstrings-dominant" strategy i.e. decreased quadriceps coupled with increased hamstrings EMG activity in both running and jumping/landing irrespective of graft type. One study reported that on the grounds of decreased quadriceps activity, lower hamstrings EMG activity was predictive of ipsilateral re-injury in ACLR patients.

CONCLUSION

This systematic review of Level III evidence showed that the ACLR leg displays decreased quadriceps or increased hamstrings EMG activity or both despite RTS. Simultaneous decreased quadriceps and increased hamstrings EMG activity was shown for both running and jumping/landing. From a clinical perspective this "hamstrings dominant" strategy can serve as a protective mechanism against graft re-injury.

LEVEL OF EVIDENCE

III.

The posterior cruciate ligament index as a reliable indirect sign of anterior cruciate ligament rupture is associated with the course of knee joint injury

PURPOSE

The objective of this study was to clarify the clinical value of the posterior cruciate ligament index (PCLI) in anterior cruciate ligament (ACL) rupture, to explore the relationship between the PCLI and course of disease, and to identify the influencing factors of the PCLI.

METHODS

The PCLI was defined a quotient of the X (the tibial and femoral PCL attachments) and the Y (the maximum perpendicular distance from X to the PCL). A total of 858 patients were enrolled in this case-control study, including 433 patients with ACL ruptures who were assigned to the experimental group and 425 patients with meniscal tears (MTs) who were allocated to the control group. Some patients in the experimental group have collateral ligament rupture (CLR). Information, such as the patient's age, sex, and course of disease, was recorded. All patients underwent magnetic resonance imaging (MRI) preoperatively, and the diagnosis was confirmed with the aid of arthroscopy. The PCLI and the depth of the lateral femoral notch sign (LFNS) were calculated based on the MRI findings, and the characteristics of the PCLI were explored.

RESULTS

The PCLI in the experimental group (5.1 ± 1.6) was significantly smaller than that in the control group (5.8 ± 1.6) (P < 0.05). The PCLI gradually decreased with time and was only 4.8 ± 1.4 in patients in the chronic phase (P < 0.05). This change was not due to the decrease in X but rather the increase in Y. The results also showed that the PCLI was not related to the depth of the LFNS or injuries of other structures in the knee joint. Furthermore, when the optimal cut-off point of the PCLI was 5.2 (area under the curve = 71%), the specificity and the sensitivity were 84% and 67%, respectively, but the Youden index was just 0.3 (P < 0.05).

CONCLUSION

The PCLI decreases due to the increase in Y instead of the decrease in X with time, especially in the chronic phase. The change in X in this process may be offset during imaging. In addition, there are fewer influencing factors that lead to changes in the PCLI. Therefore, it can be used as a reliable indirect sign of ACL rupture. However, it is difficult to quantify the diagnostic criteria of the PCLI in clinical practice. Thus, the PCLI as a reliable indirect sign of ACL rupture is associated with the course of knee joint injury, and it can be used to describe the instability of the knee joint.

LEVELS OF EVIDENCE

III.

Anatomical double-bundle anterior cruciate ligament reconstruction moderately improved tegner scores over the long-term: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

To assess the effects of anatomical double-bundle (DB) versus single-bundle (SB) for anterior cruciate ligament (ACL) reconstruction in skeletally mature patients with ACL injuries.

METHODS

MEDLINE, EMBASE, and CENTRAL were searched from inception to February 7, 2022 were screened for randomized controlled trials. The Anatomic Anterior Cruciate Ligament Reconstruction Checklist was used to categorize studies as anatomic. A random-effects meta-analysis was conducted, with pooled results being summarized using mean difference (MD). Risk of Bias (RoB) was assessed using the RoB 2.0 tool. Certainty of evidence was rated using GRADE.

RESULTS

A search of 1371 unique articles yielded eight eligible trials, representing 735 patients (360 DB, 375 SB) with mean (SD) age of 28.5 (2.86) years and follow-up of 52.1 (36.2) months. Most trials had moderate to low RoB. Overall, DB was not significantly better than SB on Lysholm scores (MD = 0.52, 95% CI, - 1.80-2.85, p = 0.66; moderate certainty) or subjective International Knee Documentation Committee (IKDC) scores (MD = - 0.40, 95% CI, - 4.35-3.55, p = 0.84; moderate certainty). Tegner scores were significantly higher in SB than DB in the intermediate term (MD = - 0.72, 95% CI, - 1.10 to - 0.34, p = 0.0002; high certainty), while significantly higher in DB relative to SB in the long-term (MD = 0.52, 95% CI, 0.02-1.03, p = 0.04; high certainty).

CONCLUSION

DB ACL reconstruction significantly improves Tegner scores relative to SB ACL reconstruction over the long-term (t ≥ 5 years). Intermediate term Tegner scores favour SB reconstruction. In both durations, there was no clinically significant difference based on the pre-specified minimal clinically important difference of 1.0 point. There were also no significant differences in IKDC or Lysholm scores. Surgeons should consider anatomical DB ACL reconstruction as a result of long-term improvement in patient-reported outcomes.

LEVEL OF EVIDENCE

I.

Anatomical hamstring tendons ACL reconstruction with the "linking rings" technique

Hamstring tendons (HTs) are one of the most commonly used autografts for anterior cruciate ligament (ACL) reconstruction (ACLR). However, the tendon-to-bone healing of the HTs grafts within the bone tunnels has always been a concern. Periosteum contains pluripotent stem cells with osteogenic and chondrogenic potential which can allow a direct, stronger and faster healing of the HTs graft within the bone tunnels. In this technical note, we present a modification of anatomical ACLR with the semitendinosus tendon (ST) graft and periosteum augmentation using the "linking rings" technique. The ST is harvested together with periosteum from its distal insertion. An additional free periosteal flap is harvested from the proximal tibia, below the ST insertion. The two free ends of the ST are then linked with a strong non-resorbable suture forming a ring and then folded again creating a quadruple construct with two loops at each end. The periosteum is then wrapped and sutured around the quadruple ST graft on both sides of the linking rings near the femoral and tibial tunnel opening. A technical pearl is to use one artery clamp inside the double rings at the graft ends, pull apart simultaneously and equal the tension between the strands. Another technical pearl is to not pull the periosteum to obtain the flaps, but to use instead a periosteal elevator to preserve the cambium layer which contains the pluripotent stem cells.

Is absolute or relative knee flexor strength related to patient-reported outcomes in patients treated with ACL reconstruction with a hamstring tendon autograft? An analysis of eccentric Nordic hamstring strength and seated concentric isokinetic strength

BACKGROUND

There is a need for better understanding of how knee flexor strength influence patient-reported outcomes (PROs) after anterior cruciate ligament (ACL) reconstruction. Our aim was to investigate the relationship between the eccentric NordBord test and the seated concentric Biodex test with PROs, during the first year of rehabilitation after ACL reconstruction with hamstring tendon (HT) autograft.

METHODS

Patients with an index ACL reconstruction with an HT autograft participating in a rehabilitation registry were screened for inclusion. Outcomes of interest were the correlation between absolute (N/kg or Nm/kg) and relative (limb symmetry index) knee flexor strength measured in the NordBord and Biodex with the results of PROs. The significance level was set at p < 0.05 and Pearson's correlation coefficient was used.

RESULTS

137 patients were included (47% women) with a mean age of 24.8 ± 8.4 years. There were non-significant and weak correlations between relative strength for all PROs. Significant and weak correlations between absolute strength in the Biodex with the Knee Self-Efficacy Scale₁₈ (K-SES₁₈) present at 4 and 8 months, and for the ACL-Return to Sport after Injury scale (ACL-RSI) at 12 months was observed, accounting for 8.4-15.7% of the variance. Significant and weak correlations between absolute strength in the Nordbord with the Knee injury and Osteoarthritis Outcome Scale subscale Sports and Recreation at 4 months, the K-SES₁₈ present and the ACL-RSI at 8 months were observed, accounting for 9.4-14.4% of the variance.

CONCLUSION

Absolute knee flexor strength relative to bodyweight for both the Biodex and NordBord test appeared to have a stronger relationship with perceived knee function than relative knee flexor strength, although the observed correlations were weak.

Reduced performance after return to competition in ACL injuries: an analysis on return to competition in the 'ACL registry in German Football'

PURPOSE

ACL injuries are one of the most severe injuries in football, but medical consequences and performance outcomes after return to competition are only rarely investigated. Aim of this study was to analyse the time of return to competition (RTC) in German professional, semi-professional and amateur football. Also, this investigation highlights the rate of career ending and performance outcome after RTC in different playing levels by the measurement of playing level, performed matches and played minutes.

METHODS

Database of this investigation is the 'ACL registry in German Football' with prospectively collected injury data. Between 2014 and 2018, four seasons in professional (1st-3rd league), semi-professional (4th-6th league) and amateur leagues (7th league) were analysed regarding the return to competition period and performance parameters. Data were collected for three subsequent seasons after injury and compared with the pre-injury and injury season. Data collection was performed using standardized methods.

RESULTS

A total of 607 ACL injuries were registered during the 4-year period with a mean RTC time of 337.1 day (SD: 183). After primary ACL ruptures, the fastest RTC was found in professional football (247.3 days), while in semi-professional (333.5 d; p < 0.0001) and amateur football (376.2 d; p < 0.0001) a prolonged absence was detected. Re-ruptures occurred in 17.8% (n = 108) and showed similar trend with fastest RTC in professionals (289.9 days; p = 0.002). Within the first three seasons after injury, 92 players (36.7%) in semi-professional and 24 (20%) in professionals had to end their career. Keeping the level of play was only possible for 48 (47.5%) of professionals, while only 47 (29.6%) of semi-professionals and 43 (28.1%) of amateurs were able to. Only in professional football, no significant difference could be seen in the played minutes and games after 2 years compared to the pre-injury season.

CONCLUSION

Lower playing levels and re-ruptures are the main factors for a prolonged return to competition after ACL rupture in German football. Significant reduction in playing level and a high rate of career endings were found for all levels of play. However, only professional players were able to regain their playing minutes and games 2 years after injury, while lower classed athletes did not reach the same amount within 3 years.

LEVEL OF EVIDENCE

Level III.

Anteromedial Portal Technique, but Not Outside-in Technique, Is Superior to Standard Transtibial Technique in Knee Stability and Functional Recovery After Anterior Cruciate Ligament Reconstruction: A Network Meta-analysis

PURPOSE

To compare the postoperative outcomes of 4 different femoral drilling techniques in anterior cruciate ligament reconstruction.

METHODS

Three databases were searched for randomized controlled trials comparing any 2 or more of the following femoral drilling techniques in anterior cruciate ligament reconstruction: standard transtibial (sTT), anteromedial portal (AMP), outside-in (OI), or modified transtibial (mTT) technique. A Bayesian network meta-analysis was performed to assess postoperative stability and functional recovery in terms of the side-to-side difference (measured by arthrometry), Lachman test, pivot-shift test, International Knee Documentation Committee subjective and objective scores, Lysholm score, and Tegner score. The Fisher exact probability test and χ² test were used to compare the incidences of infection and graft rupture, respectively.

RESULTS

We included 20 randomized controlled trials involving 1,515 patients. The AMP technique showed a lower side-to-side difference (standardized mean difference, -0.33; 95% credible interval [CrI], -0.53 to -0.12), higher negative rate on the pivot-shift test (odds ratio, 2.19; 95% CrI, 1.38 to 3.44), and higher International Knee Documentation Committee objective score (odds ratio, 3.13; 95% CrI, 1.42 to 7.82) than the sTT technique. However, knee stability and functional outcomes did not differ significantly between the OI and sTT techniques. Safety outcomes of the mTT technique were unavailable. The incidence of graft rupture was 5.20% for the OI technique, 2.27% for the AMP technique, and 1.51% for the sTT technique. The OI technique had a significantly higher incidence of graft rupture than the sTT technique (χ² = 4.421, P = .035). No significant difference in the incidence of infection was found between the sTT, AMP, and OI techniques (P = .281).

CONCLUSIONS

The AMP technique, but not the OI technique, was superior to the sTT technique in knee stability and functional recovery. The OI technique had a higher incidence of graft rupture than the sTT technique. There was no significant difference between the AMP and OI techniques or between the mTT technique and any other femoral drilling technique.

LEVEL OF EVIDENCE

Level II, meta-analysis of Level I and II studies.

Management after acute injury of the anterior cruciate ligament (ACL), part 2: management of the ACL-injured patient

PURPOSE

The aim of this consensus project was to create a treatment algorithm for the management of the ACL-injured patient which can serve as an aid in a shared decision-making process.

METHODS

For this consensus process, a steering and a rating group were formed. In an initial face-to-face meeting, the steering group, together with the expert group, formed various key topic complexes for which various questions were formulated. For each key topic, a structured literature search was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Sufficient consensus was defined as 80% agreement.

RESULTS

During this consensus process, 15 key questions were identified. The literature search for each key question resulted in 24 final statements. Of these 24 final statements, all achieved consensus.

CONCLUSIONS

This consensus process has shown that ACL rupture is a complex injury, and the outcome depends to a large extent on the frequently concomitant injuries (meniscus and/or cartilage damage). These additional injuries as well as various patient-specific factors should play a role in the treatment decision. The present treatment algorithm represents a decision aid within the framework of a shared decision-making process for the ACL-injured patient.

LEVEL OF EVIDENCE

Level V.

Predictors of Quadriceps Strength Asymmetry after Anterior Cruciate Ligament Reconstruction: A Chi-Squared Automatic Interaction Detection Decision Tree Analysis

INTRODUCTION

The influence of graft type on the restoration of quadriceps strength symmetry after ACL reconstruction (ACLR) has been widely studied. However, an important consideration when evaluating quadriceps symmetry is the fact that this measure can be influenced by numerous factors beyond graft type. This study sought to determine if graft type is predictive of quadriceps strength asymmetry during the first 12 months post-ACLR taking into consideration potentially influential factors (i.e., age, sex, body mass index, time post-ACLR).

METHODS

We retrospectively reviewed quadriceps strength data from 434 patients (303 female patients and 131 male patients) who had previously undergone ACLR with an autograft (hamstring tendon, quadriceps tendon [QT], patellar tendon [PT]) or allograft. Chi-Squared Automatic Interaction Detection decision tree analysis was used to evaluate if graft type is predictive of quadriceps strength asymmetry during the first 12 months post-ACLR taking into consideration age, sex, body mass index, and time post-ACLR.

RESULTS

The best predictor of quadriceps strength asymmetry was graft type. Specifically, three graft categories were identified: 1) allograft and hamstring tendon autograft, 2) PT autograft, and 3) QT autograft. The average quadriceps strength asymmetry for each of the three identified categories was 0.91, 0.87, and 0.81, respectively, and differed statistically from each other ( P < 0.001). The second-best predictor of quadriceps strength asymmetry was sex, albeit only in the PT and QT groups (with female patients having increased asymmetry). Female patients post-ACLR with a QT autograft were at highest risk for quadriceps strength asymmetry.

CONCLUSIONS

Graft type and sex are important predictors of quadriceps strength asymmetry after ACLR. Clinicians should take these factors into consideration when designing rehabilitation protocols to restore quadriceps strength symmetry during the postoperative period.

Efficacy of Repair for ACL Injury: A Meta‑analysis of Randomized Controlled Trials

We aim to compare the curative effect of primary repair for anterior cruciate ligament (ACL) injury with reconstruction and provide the reliable evidence for its clinical application. The literatures were searched in PubMed, EMBASE, Springer, and other medical literature databases published between January 1970 and June 2021. Basic characteristics, surgery technique, clinical outcome scores and physical examination results were recorded and evaluated. Seven randomized controlled trials (RCT) were eligible for inclusion. The results showed that there were no statistically significant differences between arthroscopic ACL repair and ACL reconstruction for Tegner, Lysholm, Lachman, KT-1000, range of motion (ROM), functional outcomes and reoperation rate (P>0.05), even the result of IKDC scores showed that arthroscopic repair was better than reconstruction (P=0.04). However, through the subgroup analysis, it was found that the short-term follow-up results of arthroscopic ACL repair were indeed better than those of open ACL repair. Therefore, we can assume that the arthroscopic ACL repair technique is an optional and promising surgical method to treat ACL injury.

Primary surgery versus primary rehabilitation for treating anterior cruciate ligament injuries: a living systematic review and meta-analysis

OBJECTIVE

Compare the effectiveness of primarily surgical versus primarily rehabilitative management for anterior cruciate ligament (ACL) rupture.

DESIGN

Living systematic review and meta-analysis.

DATA SOURCES

Six databases, six trial registries and prior systematic reviews. Forward and backward citation tracking was employed.

ELIGIBILITY CRITERIA

Randomised controlled trials that compared primary reconstructive surgery and primary rehabilitative treatment with or without optional reconstructive surgery.

DATA SYNTHESIS

Bayesian random effects meta-analysis with empirical priors for the OR and standardised mean difference and 95% credible intervals (CrI), Cochrane RoB2, and the Grading of Recommendations Assessment, Development and Evaluation approach to judge the certainty of evidence.

RESULTS

Of 9514 records, 9 reports of three studies (320 participants in total) were included. No clinically important differences were observed at any follow-up for self-reported knee function (low to very low certainty of evidence). For radiological knee osteoarthritis, we found no effect at very low certainty of evidence in the long term (OR (95% CrI): 1.45 (0.30 to 5.17), two studies). Meniscal damage showed no effect at low certainty of evidence (OR: 0.85 (95% CI 0.45 to 1.62); one study) in the long term. No differences were observed between treatments for any other secondary outcome. Three ongoing randomised controlled trials were identified.

CONCLUSIONS

There is low to very low certainty of evidence that primary rehabilitation with optional surgical reconstruction results in similar outcome measures as early surgical reconstruction for ACL rupture. The findings challenge a historical paradigm that anatomic instability should be addressed with primary surgical stabilisation to provide optimal outcomes.

PROSPERO REGISTRATION NUMBER

CRD42021256537.

Bilateral changes in knee joint laxity during the first year after non-surgically treated anterior cruciate ligament injury

OBJECTIVES

Analyse changes in knee laxity between 3, 6, 12 and 24 months after non-surgically treated ACL injury and to analyse associations between knee laxity and knee function, self-reported knee stability, ACL-Return to Sport after Injury (ACL-RSI), fear and confidence at different timepoints during recovery.

DESIGN

Prospective cohort study.

PARTICIPANTS

125 patients (67 males, mean age 25.0 ± 7.0 years) with acute ACL injury.

MAIN OUTCOME

Laxity was measured using KT-1000 arthrometer. Self-reported knee function was assessed using the International Knee Documentation Committee Subjective Knee Form (IKDC-SKF). Confidence and fear were assessed with questions from the ACL-RSI scale. Subjectively knee stability was assessed using SANE.

RESULTS

Knee laxity increased bilaterally from 3 to 12 months, and in the non-involved knee from 3 to 24 months (p˂0.05), although mean change was below 1 mm. Side-to-side difference in knee laxity was correlated with IKDC-SKF (r = -0.283) and knee stability in rehabilitation/sport activities (r = -0.315) at 6 months, but not with confidence/fear.

CONCLUSION

Knee laxity increased bilaterally during the first year after non-surgically treated ACL injury, though, the mean change in knee laxity was below 1 mm and the clinical significance is unknown. Knee laxity was weakly associated with knee function and perceived knee stability.

LEVEL OF EVIDENCE

Level II TRIAL REGISTRATION: NCT02931084.

No correlation between performance tests, clinical measurements and data from patient-reported outcome measures (PROM) in children reconstructed for anterior cruciate ligament injury

PURPOSE

To investigate if patient-reported outcome measures (PROMs), functional tests and clinical measures correlate well in children after reconstruction of the anterior cruciate ligament (ACL). It was hypothesized that these outcomes correlate, so it is sufficient to report only one of them.

METHODS

A consecutive group of children (< 16 years old) who had an ACL reconstruction, were prospectively followed and assessed after 1-year with Pedi-IKDC and KOOS-Child, instrumented laxity measurement, range of motion, extension strength and four performance tests. Relations between the different outcomes were calculated by partial correlation coefficient analysis, controlling for gender, age, height, and weight.

RESULTS

Outcomes were available for 141 of 163 children. There were only few positive and weak correlations between performance tests and PROM scores and between clinical measurements and PROM scores. There were weak to strong correlations between the scores from Pedi-IKDC and the scores from each of the five domains of KOOS-Child and a weak to moderate correlation between the different domains of KOOS-Child. Similar correlations were found between the different performance tests.

CONCLUSION

For children who had their ACL reconstructed there was no clinically important correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. This is an argument for always to include and report all three types of outcomes.

LEVEL OF EVIDENCE

Level II.

Timing of treatment in osteosarcoma: challenges and perspectives - a scoping review

BACKGROUND

The timing of events in the management of osteosarcoma may be critical for patient survivorship; however, the prognostic value of factors such as onset of symptoms or initiation of therapy in these patients has not been studied. This study sought to review the literature reporting treatment of osteosarcoma to determine the utility of event timing as a prognostic indicator. Due to significant heterogeneity in the literature, this study was conducted as a scoping review to assess the current state of the literature, identify strengths and weaknesses in current reporting practices, and to propose avenues for future improvement.

MAIN BODY

This review screened 312 peer-reviewed studies of osteosarcoma in any anatomic location published in an English journal for reporting of an event timing metric of any kind in a population of 6 or more. Thirty-seven studies met inclusion/exclusion criteria and were assessed for level of evidence, quality, and event timing metric. Reviewers also collated: publication year, population size, population age, tumor site, tumor type, surgical treatment, and adjuvant medical treatment. Extracted event timing data were further characterized using nine standardized categories to enable systematic analysis. The reporting of event timing in the treatment of osteosarcoma was incomplete and heterogenous. Only 37 of 312 (11.9%) screened studies reported event timing in any capacity. The period between patient-reported symptom initiation and definitive diagnosis was the most reported (17/37, 45.9%). Symptom duration was the second most reported period (10/37, 27.0%). Event timing was typically reported incidentally and was never rigorously incorporated into data analysis or discussion. No studies considered the impact of event timing on a primary outcome. The six largest studies were assessed in detail to identify pearls for future researchers. Notable shortcomings included the inadequate reporting of the definition of an event timing period and the pooling of patients into poorly defined timing groups.

CONCLUSIONS

Inconsistent reporting of event timing in osteosarcoma treatment prevents the development of clinically useful conclusions despite evidence to suggest event timing is a useful prognostic indicator. Consensus guidelines are necessary to improve uniformity and utility in the reporting of event timing.

Trends in Primary Anatomical Single-Bundle Anterior Cruciate Ligament Reconstruction Practice in Adult Patients Prevalent Among Arthroscopy Surgeons of Six Southern States of India

BACKGROUND

Although guidelines from multiple scientific studies decide the general trend in ACLR practice, there is often a variation between scientific guidelines and actual practice.

METHODS

A 17-member committee comprised of sports surgeons with experience of a minimum of 10 years of arthroscopy surgery finalized a survey questionnaire consisting of concepts in ACL tear management and perioperative trends, intraoperative and post-operative practices regarding single-bundle anatomic ACLR. The survey questionnaire was mailed to 584 registered sports surgeons in six states of south India. A single, non-modifiable response was collected from each member and analyzed.

RESULTS

324 responses were received out of 584 members. A strong consensus was present regarding Hamstring tendons preference for ACLR, graft diameter ≥ 7.5 mm, viewing femoral footprint through the anterolateral portal, drilling femoral tunnel from anteromedial portal guided by ridges and remnants of femoral footprint using a freehand technique, suspensory devices to fix the graft in femur and interference screw in the tibia and post-operative bracing. A broad consensus was achieved in using a brace to minimize symptoms of instability of an ACL tear and antibiotic soaking of graft. There was no consensus regarding the timing of ACLR, preferred graft in athletes, pre-tensioning, extra-articular procedure, and return to sports. There was disagreement over hybrid tibial fixation and suture tapes to augment graft.

CONCLUSION

Diverse practices continue to prevail in the management of ACL injuries. However, some of the consensuses reached in this survey match global practices. Contrasting or inconclusive practices should be explored for potential future research.

Failure of primary ACL repair with dynamic intraligamentary stabilization may result in a high risk of two-stage ACL reconstruction: a case series of ten patients

PURPOSE

Dynamic Intraligamentary Stabilization (DIS) is a technique for the repair of acute anterior cruciate ligament (ACL) injuries. The purpose of this study was to investigate the potential challenges of ACL reconstruction (ACLR) following failure of DIS.

METHODS

A retrospective analysis of patients with failure of primary ACL repair performed with DIS was undertaken. Failure was defined as abnormal knee laxity (positive Lachman and/or pivot shift) and/or severely restricted range of motion. Medical and surgical records were reviewed and preoperative standard anteroposterior and lateral X-rays were assessed.

RESULTS

Between July 2015 and May 2022, 10 patients (3 males, 7 females, median age 28 years, range 18-52 years) with failure of DIS were referred to and surgically treated at a single centre. In four patients, single-stage ACLR was performed following the removal of the tibial monoblock. In six patients, arthrofibrosis and excessive tibial tunnel enlargement following the removal of the monoblock prevented single-stage ACLR. These patients underwent arthroscopic arthrolysis and tibial tunnel bone grafting as a first-stage revision procedure.

CONCLUSION

In the present case series, single-stage ACLR was performed in only four (40%) of ten patients following failure of ACL repair with DIS. Arthrofibrosis and excessive tibial tunnel enlargement following the removal of the monoblock prevented single-stage ACLR in six (60%) patients. It is important for clinicians to inform patients that, in the event of failure of ACL repair with DIS, they may run a high risk of undergoing two-stage ACLR.

LEVEL OF EVIDENCE

Level IV, Case Series.

Treatment decision-making process after an anterior cruciate ligament injury: patients', orthopaedic surgeons' and physiotherapists' perspectives

Objective

To investigate the treatment decision-making process after an anterior cruciate ligament (ACL) injury from patients’, orthopaedic surgeons’ and physiotherapists’ perspectives.

Methods

The study is a part of the NACOX study, which is designed to describe the natural corollaries after ACL injury. For the present study, a subgroup 101 patients were included. Patients, their orthopaedic surgeons and their physiotherapists, answered a Shared Decision-Making Process (SDMP) questionnaire, when treatment decision for ACL reconstruction surgery (ACLR) or non-reconstruction (non-ACLR) was taken. The SDMP questionnaire covers four topics: “ informed patient”, “ to be heard”, “ involvement” and “ agreement”.

Results

Most (75–98%) patients considered their needs met in terms of being heard and agreement with the treatment decision. However, fewer in the non-ACLR group compared to the ACLR group reported satisfaction with information from the orthopaedic surgeon (67% and 79%), or for their own involvement in the treatment decision process (67% and 97%).

Conclusion and practice implications

Most patients and caregivers considered that patients’ needs to be informed, heard and involved, and to agree with the decision about the treatment process, were fulfilled to a high extent. However, patients where a non-ACLR decision was taken experienced being involved in the treatment decision to a lower extent. This implies that the non-ACLR treatment decision process needs further clarification, especially from the patient involvement perspective.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05745-4.

Impaction Of Rehabilitations And Strengthening Programs before And after Anterior Cruciate Ligament Reconstruction In Return to the Fitness Level

Objectives. Sports injuries are one of the most common orthopedic injuries particularly in young and active populations. Football is the most popular sport among Saudis, and thus, anterior cruciate ligament (ACL) injuries are common in clinics and emergency rooms in Saudi Arabia. The aim of this study was to evaluate the outcomes of patients six months after ACL reconstruction in both hospitals and gym-based rehabilitation services and its impaction on the patients to return to sports and preinjury fitness levels. Methods. This is a retrospective case series of patients who underwent arthroscopically assisted ACL reconstruction using a hamstring autograft at our center. Data were gathered from January 2020 to December 2020. Patients were given a questionnaire about their visits to the orthopedic clinic in the 6th month after surgery. Results. Sixty patients with ACL reconstructions were studied. Noncontact sports were the leading cause of injuries (53.3%). The mean Lysholm score was 84.9 (SD 3.45) out of 100 after six months of follow-up, and the mean Tegner score was 4.77 (SD 1.06) out of 10 points. The Lysholm score was excellent (>90) among 5% (n= 3), good (84–90) among 60% (n= 36), and fair (65–83) among 35% (n= 21). As a result, we observed that the duration of postoperative rehabilitation has a significant relationship with the fitness level (X2= 18.711; $p=0.001$ ).Conclusion. The Lysholm knee scoring scale and the Tegner activity scale showed that arthroscopically assisted ACL reconstruction using hamstring autograft has a successful and functional outcome after which the patient returns to sports or regains the preinjury level of fitness level depends on the rehabilitation.The period and types of preoperative and postoperative rehabilitation have a direct impact on the return to fitness levels and normal daily life activities.

K-Space Data Reconstruction Algorithm-Based MRI Diagnosis and Influencing Factors of Knee Anterior Cruciate Ligament Injury

This study was aimed at investigating the diagnostic value of MRI based on K-space data reconstruction algorithm for anterior cruciate ligament (ACL) injury of knee joint and the influencing factors of ligament injury. 96 patients with ACL injury of knee joint were selected, and they were randomly divided into two groups: group A (arthroscopy) and group B (MRI examination), and another 96 healthy volunteers in the same period were selected as the control group. The test results of each indicator were compared. The results showed that the signal-to-noise ratio (SNR) of SMASH algorithm was higher than that of sum of squares (SOS) algorithm. In group A, there were 66 positive and 30 negative tests, and in group B, there were 56 positive and 40 negative tests (P < 0.05). The intercondylar fossa width, the intercondylar fossa width index, and the ratio of tibial intercondylar eminence width to intercondylar fossa width in group B were lower than those in the control group (P < 0.05). Compared with the traditional SOS algorithm, SMASH algorithm can improve the image quality, reduce the impact of damage data on the final synthesis image, and improve the image SNR. In clinical work, the ratio of the width of tibial intercondylar eminence to the width of femoral intercondylar fossa can be measured by imaging data to evaluate the matching between tibial intercondylar eminence and femoral intercondylar fossa, so as to evaluate the risk of ACL rupture.

Fear of Movement and Reinjury in Sports Medicine: Relevance for Rehabilitation and Return to Sport

Athletes are defined by their ability to move and are often accustomed to pain as it relates to their sports and exercise regime. The forced movement restriction and pain associated with an acute or overuse injury has a profound effect not only on their physical abilities but also on their psychological well-being and social context. With the goal of returning to sport, the rehabilitation focus historically has been on recovery of physical attributes, but more recent research is addressing the psychological factors. This Perspective proposes that-according to the current evidence in sports medicine-the fear that affects choice of treatment, rehabilitation, and return to sports is intertwined with physical capacity and recovery of function. Past injury is also 1 of the main risk factors for a sports injury; therefore, fear of reinjury is not irrational. For an athlete, the fear related to a sports injury encompasses the fear of reinjury along with fear of not being able to return to the sport at their highest performance level-and the fear of having lifelong debilitating pain and symptoms. This Perspective reviews the evidence for the influence of fear of movement and reinjury on choice of treatment, rehabilitation, and return to sport and provides suggestions on how to address this fear during the continuum of treatment and return to sports.

Remnants-preserving ACL reconstruction using direct tendinous graft fixation: a new rat model

BACKGROUND

Anterior cruciate ligament (ACL) repair techniques are new emerging strategies prevailing, in selected cases, over standard reconstruction of the ACL with excision of its remnants. Mid-substance ACL tears represent a challenge for ACL repair techniques, and remnants-preserving ACL reconstruction (rp-ACLR) using an autograft remains the recommended treatment in this situation. However, morbidity associated with the autograft harvesting prompts the need for alternative surgical strategies based on the use of synthetic scaffolds. Relevant small animal models of mid-substance tears with ACL remnants preservation and reconstruction are necessary to establish the preliminary proof of concept of these new strategies.

METHODS

A rat model of rp-ACLR using a tendinous autograft after complete mid-substance ACL transection was established. Twelve weeks following surgery, clinical outcomes and knee joints were assessed through visual gait analysis, Lachman tests, thigh perimeter measurements, magnetic resonance imaging, micro-computed tomography, and histology, to evaluate the morbidity of the procedure, accuracy of bone tunnel positioning, ACL remnants fate, osteoarthritis, and autograft bony integration. Results were compared with those obtained with isolated ACL transection without reconstruction and to right non-operated knees.

RESULTS AND DISCUSSION

Most operated animals were weight-bearing the day following surgery, and no adverse inflammatory reaction has been observed for the whole duration of the study. Autograft fixation with cortical screws provided effective graft anchorage until sacrifice. Healing of the transected ACL was not observed in the animals in which no graft reconstruction was performed. rp-ACLR was associated with a reduced degeneration of the ACL remnants (p = 0.004) and cartilages (p = 0.0437). Joint effusion and synovitis were significantly lower in the reconstructed group compared to the transected ACL group (p = 0.004). Most of the bone tunnel apertures were anatomically positioned in the coronal and/or sagittal plane. The most deviated bone tunnel apertures were the tibial ones, located in median less than 1 mm posteriorly to anatomical ACL footprint center.

CONCLUSION

This study presents a cost-effective, new relevant and objective rat model associated with low morbidity for the preliminary study of bio-implantable materials designed for remnants-preserving ACL surgery after mid-substance ACL tear.