Systematic review: Annual incidence of ACL injury and surgery in various populations

Development of an intervention for patients following an anterior cruciate ligament rupture: an online nominal group technique consensus study

OBJECTIVES

(1) To develop an intervention for to support patients diagnosed with an anterior cruciate ligament (ACL) rupture with decision-making regarding treatment. (2) To define evidence-based recommendations for the treatment of patients following an ACL rupture.

DESIGN

Nominal group technique consensus study.

SETTING

Online meetings with patients and key stakeholders working and receiving treatment in the National Health Service, UK.

PARTICIPANTS

Consensus meetings composed of eight voting participants and five non-voting facilitators. Voting participants included five clinicians, one outpatient therapy manager and two patients with experience in an ACL rupture and reconstructive surgery. Non-voting facilitators supported group discussions and/or observed study procedures. This included a clinical academic expert, two methodology experts and two patient representatives.

METHOD

Two online meetings were held. Pre-elicitation material was distributed ahead of the first meeting. Premeeting voting was conducted ahead of both meetings. A draft of the shared decision-making intervention and recommendations were shared ahead of the second meeting. Components were discussed and ranked for inclusion based on a 70% agreement threshold.

RESULTS

The meetings led to the development of a shared decision-making intervention to support treatment decision-making following an ACL rupture. The intervention includes two components: (1) a patient information leaflet and key questions diagram and (2) option grid. The evidence-based recommendations encompass core components of treatment reaching the 70% threshold agreed by the group. The recommendations cover: (1) advice and education, (2) exercise guidance, (3) intervention delivery, (4) outcome measure use and (5) shared decision-making.

CONCLUSION

This study has successfully developed a shared decision-making intervention to support ACL treatment decision-making, ready for testing in a future feasibility study. Evidence-based recommendations for the treatment of patients following ACL injury, ready for testing in a National Health Service (UK) setting, are also presented.

TRIAL REGISTRATION NUMBER

NCT05529511.

Cost-utility analysis of early reconstruction surgery versus conservative treatment for anterior cruciate ligament injury in a lower-middle income country

BACKGROUND

The ideal approach for treating anterior cruciate ligament (ACL) injury is still disputed. This study aimed to determine the more cost-effective strategy by comparing early ACL reconstruction (ACLR) surgery to conservative treatment (rehabilitation with optional delayed reconstruction) for ACL injury in a lower/middle-income country (LMIC), Indonesia.

METHODS

A decision tree model was constructed for cost-utility analysis of early ACLR versus conservative treatment. The transition probabilities between states were obtained from the literature review. Utilities were measured by the EQ-5D-3 L from a prospective cohort study in a local hospital. The costs were obtained from a previous study that elaborated on the burden and cost of ACLR in Indonesia. Effectiveness was expressed in quality-adjusted life years gained (QALYs). Principal outcome measure was the incremental cost-effectiveness ratios (ICER). Willingness-to-pay was set at US$12,876 - three times the Indonesian GDP per capita in 2021 - the currently accepted standard in Indonesia as suggested by the World Health Organization Choosing Interventions that are Cost-Effective criterion (WHO-CHOICE).

RESULTS

The early ACLR group showed an incremental gain of 0.05 QALYs over the conservative treatment group, with a higher overall cost to society of US$976. The ICER of ACLR surgery was US$19,524 per QALY, above the WTP threshold of US$12,876. The ICER was sensitive to cost of conservative treatment, cost of ACLR, and rate of cross-over to delayed ACLR numbers in the conservative treatment group. Using the WTP threshold of US$12,876, the probability of conservative treatment being preferred over early ACLR was 64%.

CONCLUSIONS

Based on the current model, early ACLR surgery does not seem more cost-effective compared to conservative treatment for ACL injury patients in Indonesia. Because the result was sensitive to the rate of cross-over probabilities from the conservative treatment alone to delayed ACLR, a future study with a long-term perspective is needed to further elucidate its impact.

Ambulatory knee arthroscopic surgery yields cost savings and improved health outcomes

PURPOSE

This study measured the health-related quality of life (HRQoL) and costs and conducted a cost-utility analysis and budget impact analysis of ambulatory knee arthroscopic surgery compared with inpatient knee arthroscopic surgery in Thailand from a societal perspective.

METHODS

Health outcomes were measured in units of quality-adjusted life year (QALY) based on the Thai version of the EQ-5D-5L Health Questionnaire, and costs were obtained from an electronic database at a tertiary care hospital (Ramathibodi Hospital). A cost-utility analysis was performed to evaluate ambulatory and inpatient surgery using the societal perspective and a 2-week time horizon. The incremental cost-effectiveness ratio was applied to examine the costs and QALYs. One-way sensitivity analysis was used to investigate the robustness of the model. Budget impact analysis was performed considering over 5 years.

RESULTS

A total of 161 knee arthroscopic patients were included and divided into two groups: ambulatory surgery (58 patients) and inpatient surgery (103 patients). The total cost of the inpatient surgery was 2235 United States dollars (USD), while the ambulatory surgery cost was 2002 USD. The QALYs of inpatient surgery and ambulatory surgery were 0.79 and 0.81, respectively, resulting in the ambulatory surgery becoming a dominant strategy (cost reduction of 233 USD with an increase of 0.02 QALY) over the inpatient surgery. The ambulatory surgery led to net savings of 4.5 million USD over 5 years. Medical supply costs are one of the most influential factors affecting the change in results.

CONCLUSION

Ambulatory knee arthroscopic surgery emerged as a cost-saving strategy over inpatient surgery, driven by lower treatment costs and enhanced HRQoL. Budget impact analysis indicated net savings over 5 years, supporting the feasibility of adopting ambulatory knee arthroscopic surgery. Our findings were advocated for its application across diverse hospitals and informed policymakers to improve reimbursement systems in low- to middle-income countries and Thailand.

LEVEL OF EVIDENCE

Level IV.

Enhancing tendon-bone integration and healing with advanced multi-layer nanofiber-reinforced 3D scaffolds for acellular tendon complexes

Advancements in tissue engineering are crucial for successfully healing tendon-bone connections, especially in situations like anterior cruciate ligament (ACL) restoration. This study presents a new and innovative three-dimensional scaffold, reinforced with nanofibers, that is specifically intended for acellular tendon complexes. The scaffold consists of a distinct layered arrangement comprising an acellular tendon core, a middle layer of polyurethane/type I collagen (PU/Col I) yarn, and an outside layer of poly (L-lactic acid)/bioactive glass (PLLA/BG) nanofiber membrane. Every layer is designed to fulfill specific yet harmonious purposes. The acellular tendon core is a solid structural base and a favorable environment for tendon cell functions, resulting in considerable tensile strength. The central PU/Col I yarn layer is vital in promoting the tendinogenic differentiation of stem cells derived from tendons and increasing the expression of critical tendinogenic factors. The external PLLA/BG nanofiber membrane fosters the process of bone marrow mesenchymal stem cells differentiating into bone cells and enhances the expression of markers associated with bone formation. Our scaffold's biocompatibility and multi-functional design were confirmed through extensive in vivo evaluations, such as histological staining and biomechanical analyses. These assessments combined showed notable enhancements in ACL repair and healing. This study emphasizes the promise of multi-layered nanofiber scaffolds in orthopedic tissue engineering and also introduces new possibilities for the creation of improved materials for regenerating the tendon-bone interface.

Decreased moment of inertia of the lower limb facilitates a rapid hip internal rotation in a simulated foot impact maneuver. A laboratory-controlled biomechanical study for a precursor mechanism of noncontact anterior cruciate ligament injury

BACKGROUND

Anterior cruciate ligament injury frequently occurs in the deceleration with the knee-extended position. In addition, a rapid hip internal rotation is concomitantly observed. However, how the extended knee position induces the hip internal rotation is unclear.

METHODS

Sixteen healthy participants performed the simulated foot impact task on the experimental chair. To vary the knee flexion angle, the following four-foot placement positions relative to the pelvis segment, i.e.: 1) near; 2) middle; 3) far; and 4) far + heel strike, were tested. The reflective marker positions and the ground reaction force (GRF) data were collected. The moment of inertia of the entire lower limb around its long axis as well as the peak hip internal rotation angular velocity were calculated and compared among four conditions (Wilcoxon Signed-Rank Test with Bonferroni correction, P<0.0083).

RESULTS

As the knee extended from the near to far + heel strike condition, the moment of inertia of the entire lower limb significantly decreased and hip internal rotation angular velocity significantly increased (P<0.001).

CONCLUSIONS

The extended knee position with far foot placement from torso reduces the inertial resistance of the entire lower limb around its long axis and is vulnerable to the hip internal rotation.

No difference was found between double-bundle and single-bundle anterior cruciate ligament reconstructions in terms of osteoarthritis at 15-year follow-up

PURPOSE

The purpose of the study was to determine whether the grade of osteoarthritis (OA) is higher with single-bundle (SB) or double-bundle (DB) anterior cruciate ligament (ACL) reconstruction. The hypothesis was that there will be no difference in the grade of OA between the techniques.

METHODS

This study was a randomised controlled trial (RCT) with a follow-up period of 15 years. Patients were randomly assigned to either the SB group (n = 78) or the DB group (n = 75). Surgical techniques were anatomic, and the rehabilitation protocol was standardised. Evaluation included Kellgren-Lawrence (KL) difference and absolute OA results. OA was defined as a KL grade of at least 2.

RESULTS

At 15-year follow-up, information was available on 101 patients (66%), of whom 56 (37%) were accepted in the final statistical analysis. No difference was found between the SB and DB techniques in terms of KL difference or absolute OA results. Significantly less OA was found in the contralateral knee (21%) than in the reconstructed knee (59%) (p < 0.001). Patients with meniscal tears who underwent partial meniscal resection during ACL reconstruction had a significantly higher rate of OA changes (82%) compared with patients with isolated ACL tears (33%) (p < 0.001). A longer delay between initial injury and surgery did not appear to affect the severity of the KL classification.

CONCLUSION

At 15-year follow-up, no difference was found between the DB and SB techniques in terms of OA.

LEVEL OF EVIDENCE

Level I.

Anterior Cruciate Ligament Reconstruction in French Army: Return to Prior Level of Running on Selected Military Tests

INTRODUCTION

Anterior cruciate ligament (ACL) rupture is frequently encountered in athletes as well as in military personnel. In civilian population, many studies have looked at the return to sport, but return to duty in Army is a topic that requires further research.The purpose of this study was to determine through annual military fitness tests in real conditions, the return to sport in soldiers after ACL reconstruction and factors influencing failure.

MATERIALS AND METHODS

This was a retrospective comparative study. Patients were all soldiers and had followed up in a Military Hospital. The SUCCESS group was military personnel who obtained a result of the specific aptitude test greater than or equal to this same test carried out before reconstruction of the ACL, the FAILURE group comprised the others. Results of the annual specific aerobic fitness tests were collected before and after ACL reconstruction. Preoperative epidemiological data, intraoperative information, and isokinetic test results were collected.

RESULTS

One hundred forty four soldiers were included between January 2011 and December 2017 (94.9% of men with a median age of 27.6 years); 40.3% obtained a result greater than or equal to the preoperative fitness test after ACL reconstruction. Among the soldiers who did not regain their performance, 24.3% were declared unfit or discharged. In the FAILURE group, we found patients with a higher body mass index (25.5 vs. 24.4; P = .04), less patients with isokinetic deficit < 30% on the knee flexors and extensors (26.6% vs. 62.9%; P < .01), more long sick leave (39.5% vs. 13.7%; P < .01), and late resumption of military activities (10.5 vs. 8.9 months; P < .01).

CONCLUSION

Rupture of ACL has a significant impact on the operational capacity of the French army. The proportion of return to the same level in annual specific fitness tests after ACL reconstruction is 40% among soldiers. Several variables are important to consider in the follow-up of these patients to optimize their recovery of sports performance and therefore their operational capacity.

Implementing a shared decision-making intervention to support treatment decisions for patients following an anterior cruciate ligament rupture - a protocol for the POP-ACLR feasibility study

BACKGROUND

Treatment for anterior cruciate ligament (ACL) rupture may follow a surgical or nonsurgical pathway. At present, there is uncertainty around treatment choice. Two shared decision-making tools have been codesigned to support patients to make a decision about treatment following an ACL rupture. The shared decision-making tools include a patient information leaflet and an option grid. We report the protocol for a mixed-methods feasibility study, with nested qualitative interviews, to understand feasibility, acceptability, indicators of effectiveness and implementation factors of these shared decision-making tools (combined to form one shared decision-making intervention).

METHODS

A single-centre non-randomised feasibility study will be conducted with 20 patients. Patients diagnosed with an ACL rupture following magnetic resonance imaging will be identified from an orthopaedic clinic. The shared decision-making intervention will be delivered during a clinical consultation with a physiotherapist. The primary feasibility outcomes include the following: recruitment rate, fidelity, acceptability and follow-up questionnaire completion. The secondary outcome is the satisfaction with decision scale. The nested qualitative interview will explore experience of using the shared decision-making intervention to understand acceptability, implementation factors and areas for further refinement.

DISCUSSION

This study will determine the feasibility of using a newly developed shared decision-making intervention designed to support patients to make a decision about treatment of their ACL rupture. The acceptability and indicators of effectiveness will also be explored. In the long term, the shared decision-making intervention may improve service and patient outcomes and ensure cost-effectiveness for the NHS; ensuring those most likely to benefit from surgical treatment proceed along this pathway.

TRIAL REGISTRATION

Pending registration on ISRCTN.

Associations of patient characteristics, rate of torque development, voluntary activation of quadriceps with quadriceps strength, and knee function before anterior cruciate ligament reconstruction

Good preoperative knee function (KF) and quadriceps strength (QS) relate to good prognoses after anterior cruciate ligament reconstruction (ACLR). This study aimed to investigate the associations between patient characteristics, rate of torque development (RTD), voluntary activation (VA) of the quadriceps against preoperative KF and QS. A cross-sectional study was conducted. Forty patients with a primary, unilateral ACL injury who had finished the preoperative rehabilitation and scheduled for an ACLR were included. KF was evaluated using the International Knee Documentation Committee score. QS was measured by maximal voluntary isometric contractions. RTD was divided into the early (RTD0-50) and the late (RTD100-200) phases. Quadriceps VA was measured using the superimposed burst technique. Our results showed that patients with poor preoperative KF    had more deficits in RTD0-50 (P = 0.025), higher BMI(P = 0.043), and more meniscus injuries (MI) (P = 0.001) than those with good KF. Patients with asymmetrical QS   showed lower BMI (P = 0.020) and shorter time from injury (TFI) (P = 0.027) than those with symmetrical QS. Additionally, a higher pre-injury Tegner score combined with greater RTD100-200 contributed to greater QS on the injured limb (R2 = 0.357, P = 0.001). To conclude, BMI, TFI, concomitant MI, pre-injury physical activity level, and quadriceps RTD are related to QS and KF before ACLR.

Most Anterior Cruciate Ligament Injuries in Professional Athletes Occur Without Contact to the Injured Knee: A Systematic Review of Video Analysis Studies

PURPOSE

To systematically review studies using video analyses to evaluate anterior cruciate ligament (ACL) injury mechanisms in athletes during sport to better understand risk factors and the potential for injury prevention.

METHODS

A literature search was conducted in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines statement using SCOPUS, PubMed, Medline, and the Cochrane Central Register for Controlled Trials from database inception through June 2023. Inclusion criteria included studies reporting on ACL injury mechanisms occurring in athletes based on video analysis. Athlete demographics, injury mechanisms, position of the lower extremity, and activity at the time of injury were recorded.

RESULTS

A total of 13 studies, consisting of 542 athletes, met inclusion criteria. Most athletes competed at the professional level (91%, n = 495/542), with 79% (n = 422/536) of athletes being male. The most common sports were soccer (33%, n = 178/542) and American football (26%, n = 140/542). The most common injury mechanism was noncontact in 42.9% (n = 230/536) of athletes, followed by indirect contact (32.6%, n = 175/536) and direct contact (22.4%, n = 120/536). The most common position of injury was with a planted foot (91.7%, n = 110/120), full or near-full knee extension (84.4%, n = 49/58), and axial loading (81.3%, n = 87/107). Injuries commonly involved a deceleration/shift in momentum (50.4%, n = 123/244) or pivoting maneuver (36.1%, n = 77/213). At the time of injury, the knee commonly fell into valgus (76.8%, n = 225/293) with associated internal (53.5%, n = 46/86) or external tibiofemoral rotation (57.7%, n = 101/175).

CONCLUSIONS

Most ACL injuries, when evaluated by video analysis, involve professional athletes participating in soccer and American football. The most common injury mechanism occurred without contact with the knee in extension during a deceleration or momentum shift, with resultant valgus and rotational force across the knee.

LEVEL OF EVIDENCE

Level IV, systematic review of Level IV studies.

Comparison of Blood Flow Restriction Interventions to Standard Rehabilitation After an Anterior Cruciate Ligament Injury: A Systematic Review

BACKGROUND

Blood flow restriction training (BFR-t) data are heterogeneous. It is unclear whether rehabilitation with BFR-t after an anterior cruciate ligament (ACL) injury is more effective in improving muscle strength and muscle size than standard rehabilitation.

PURPOSE

To review outcomes after an ACL injury and subsequent reconstruction in studies comparing rehabilitation with and without BFR-t.

STUDY DESIGN

Systematic review. Level of evidence, 3.

METHODS

A search of English-language human clinical studies published in the past 20 years (2002-2022) was carried out in 5 health sciences databases, involving participants aged 18-65 undergoing rehabilitation for an ACL injury. Outcomes associated with muscle strength, muscle size, and knee-specific patient-reported outcome measures (PROMs) were extracted from studies meeting inclusion criteria and compared.

RESULTS

The literature search identified 279 studies, of which 5 met the selection criteria. Two studies suggested that BFR-t rehabilitation after an ACL injury improved knee or thigh muscle strength and muscle size compared with rehabilitation consisting of comparable and higher load resistance training, with two studies suggesting the opposite. The single study measuring PROMs showed improvement compared to traditional rehabilitation, with no difference in muscle strength or size.

CONCLUSION

BFR-t after an ACL injury seems to benefit muscle strength, muscle size, and PROM scores compared with standard rehabilitation alone. However, only 1 large study included all these outcomes, which has yet to be replicated in other settings. Further studies utilizing similar methods with a common set of outcome measures are required to confirm the effects of BFR-t on ACL rehabilitation.

Refined Detection and Classification of Knee Ligament Injury Based on ResNet Convolutional Neural Networks

Currently, medical imaging has largely supplanted traditional methods in the realm of diagnosis and treatment planning. This shift is primarily attributable to the non-invasive nature, rapidity, and user-friendliness of medical-imaging techniques. The widespread adoption of medical imaging, however, has shifted the bottleneck to healthcare professionals who must analyze each case post-image acquisition. This process is characterized by its sluggishness and subjectivity, making it susceptible to errors. The anterior cruciate ligament (ACL), a frequently injured knee ligament, predominantly affects a youthful and sports-active demographic. ACL injuries often leave patients with substantial disabilities and alter knee mechanics. Since some of these cases necessitate surgery, it is crucial to accurately classify and detect ACL injury. This paper investigates the utilization of pre-trained convolutional neural networks featuring residual connections (ResNet) along with image-processing methods to identify ACL injury and differentiate between various tear levels. The ResNet employed in this study is not the standard ResNet but rather an adapted version capable of processing 3D volumes constructed from 2D image slices. Achieving a peak accuracy of 97.15% with a custom split, 96.32% through Monte-Carlo cross-validation, and 93.22% via five-fold cross-validation, our approach enhances the performance of three-class classifiers by over 7% in terms of raw accuracy. Moreover, we achieved an improvement of more than 1% across all types of evaluation. It is quite clear that the model's output can effectively serve as an initial diagnostic baseline for radiologists with minimal effort and nearly instantaneous results. This advancement underscores the paper's focus on harnessing deep learning for the nuanced detection and classification of ACL tears, demonstrating a significant leap toward automating and refining diagnostic accuracy in sports medicine and orthopedics.

Anterior Cruciate Ligament Reconstruction Using Allograft in Adults Older Than the Age of 40 Years Shows Similar Patient-Reported Outcomes Between Male and Female Patients

Purpose

To evaluate patient-reported outcomes in patients undergoing anterior cruciate ligament (ACL) reconstruction using allograft in patients 40 years of age or older divided by sex.

Methods

Patients age 40 years of age or older who underwent ACL reconstruction by the same surgeon using allograft via anteromedial portal technique were retrospectively identified. Patient-reported outcomes (International Knee Documentation Committee [IKDC], Knee Injury and Osteoarthritis Outcome Score, Tegner, Lysholm, Marx, and Single Assessment Numeric Evaluation) were evaluated and recorded, and outcomes were analyzed by sex.

Results

In total, 159 patients undergoing primary ACL reconstruction were reviewed. Two-year outcomes were obtained. All patients noted improvement in patient-reported outcome measures. Male patients had overall greater postoperative patient-reported outcomes measures at all time points for IKDC, Tegner, Lysholm, Marx, and Single Assessment Numeric Evaluation scores; however, the only significant time points were IKDC 6 months (P = .016), 1 year (P = .012) and Marx 1 year (P = .007) and 2 year (P = .016). Knee Injury and Osteoarthritis Outcome Score scores similarly showed greater postoperative scores at all time points and statistical significance at 3 months (P = .002), 6 months (P = .033), and 1 year (P = .031).

Conclusions

ACL reconstruction in individuals older than the age of 40 years using allograft results in good outcomes compared with preoperative status. Patient-reported outcomes were similar between male and female patients regarding most patient-reported outcome measures.

Level of Evidence

Level III, retrospective cohort study.

Influence of hamstring stiffness on anterior tibial translation after anterior cruciate ligament rupture

BACKGROUND

There is a correlation between the hamstring stiffness and the decrease of anterior tibial translation in athletic patients with healthy knees. This observation could question the clinical reliability of the Lachman-Trillat test to detect complete ACL ruptures in patients with an important hamstring stiffness. This study aims to determine if anterior tibial translation is correlated with hamstring stiffness in patients with complete ACL rupture.

METHODS

This is a prospective study including patients with unilateral complete ACL rupture confirmed by MRI. The arthrometer GNRB® was used to measure anterior tibial translation on both knees at 134 N and compute the side-to-side difference. The hamstring stiffness was assessed with the eccentric peak torque using the isokinetic dynamometer CON-TREX. Linear regressions were done between these two parameters on two study groups: one included all patients (GR1), and the other included only isolated ACL injuries without associated lesions (GR2).

RESULTS

Fifty-two patients were included (29 men, 23 women) with an average of 34.9 years old. The mean eccentric peak torque of the hamstrings for pathological knees was 94.9Nm for GR1 and 91.7Nm for GR2. The mean side-to-side difference was 2.42 mm for GR1 and 1.99 mm for GR2. No significant correlations were identified for GR1 (p = 0.66) and GR2 (p = 0.105).

CONCLUSION

No significant linear correlation was found between side-to-side difference measured by GNRB® and hamstring stiffness for pathological knees with complete ACL rupture. These results lead to believe that the Lachman-Trillat clinical test is not influenced by hamstring stiffness.

LEVEL OF EVIDENCE

Prospective study, level of evidence IV.

Fragile Statistical Findings in Randomized Controlled Trials Evaluating Autograft Versus Allograft Use in Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To analyze the statistical stability of randomized controlled trials (RCTs) evaluating the surgical management of autografts versus allografts in the anterior cruciate ligament reconstruction (ACLR) literature and calculate the fragility index (FI) and fragility quotient and explore a subgroup analysis by calculating the proportion of outcome events where the FI was less than the number of patients lost to follow-up.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a systematic search in the PubMed and Cochrane databases to identify RCTs published between 2000 and 2022 that investigated the use of autografts versus allografts in ACLR literature and reported dichotomous data. The fragility index of each dichotomous variable was calculated through the reversal of a single outcome event until significance was reversed. The fragility quotient was calculated by dividing each fragility index by the study sample size. The interquartile range also was calculated.

RESULTS

Of the 4407 articles screened, 23 met the search criteria, with 11 RCTs evaluating ALCR using autografts and allografts included for analysis. Two hundred and 18 outcome events with 32 significant (P < .05) outcomes and 186 nonsignificant (P ≥ .05) outcomes were identified. The overall fragility index and fragility quotient for all 218 outcomes were 6 subjects (interquartile range 5-8) and 0.058 (interquartile range 0.039-0.077). Fragility analysis of statistically significant outcomes and nonsignificant outcomes had a fragility index of 3.5 (interquartile range 1-5.5) and 6 (interquartile range 5-8), respectively. All of the studies reported a loss to follow-up where 45.5% (5) reported a loss to follow-up greater or equal to 6.

CONCLUSIONS

The RCTs in the ACLR peer-reviewed literature evaluating autograft versus allograft use are vulnerable to a small number of outcome event reversals and exemplify significant statistical fragility in statistically significant findings.

LEVEL OF EVIDENCE

Level I, systematic review of Level I studies.

Effect of Postoperative Kinesio Taping on Knee Edema, Pain, and Range of Motion After Total Knee Arthroplasty and Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis of Randomized Clinical Trials

BACKGROUND

Kinesio taping (KT) has been shown to be clinically effective in a wide range of musculoskeletal disorders. Despite evidence supporting KT, there still needs to be more certainty regarding its clinical worthiness in managing postoperative conditions. This study aims to assess the effect of postoperative KT on knee edema, pain, and range of motion (ROM) when added to routine physiotherapy after knee surgery.

METHODS

In this systematic review and meta-analysis, MEDLINE, Embase, Scopus, Web of Science, and CENTRAL databases were searched from their inception to July 2023. Randomized controlled trials (RCTs) comparing routine physiotherapy with and without KT were included. Random-effect models were used to calculate the standardized mean difference (SMD), confidence interval, and heterogeneity (I2).

RESULTS

Sixteen RCTs on 842 operated knees were included. KT reduced knee edema in first week (SMD, -0.59, p < 0.001), 14th postoperative day (POD) (SMD, -0.78, p < 0.001), and 28 to 42 days postop (SMD, -0.66, p < 0.001). The KT demonstrated significant pain improvement in second week (SMD, -0.87, p < 0.001) and the fourth week (SMD, -0.53, p < 0.001). The KT groups demonstrated ROM improvement within second week (SMD, 0.69, p = 0.010) and in the 28th POD (SMD, 0.89, p = 0.009). Subgroup analysis demonstrated minimal heterogeneity in anterior cruciate ligament reconstruction (ACLR) cases. However, it did not show significant superiority regarding ankle, calf, or thigh edema and Lysholm scale.

CONCLUSION

This study suggests that adding KT to routine postoperative physiotherapy reduces pain and knee edema after total knee arthroplasty or ACLR. Low to very low certainty of evidence for all outcomes and the limited number of studies emphasize the need for more high-quality primary studies to explore the optimal method of KT application and its effectiveness in specific knee surgeries.

LEVEL OF EVIDENCE

Level I. See Instructions for Authors for a complete description of levels of evidence.

Functional outcomes of accelerated rehabilitation protocol for anterior cruciate ligament reconstruction in amateur athletes: a randomized clinical trial

BACKGROUND

Anterior cruciate ligament (ACL) rupture is the most common knee injury among athletes, and can result in long-term complications and career-ending conditions for sportspeople. There is no consensus in the literature on the effectiveness of rehabilitation after ACL reconstruction, or the best protocol to follow for functional outcome improvement.

OBJECTIVE

To determine the impact of an accelerated rehabilitation protocol on knee functional outcomes in amateur athletes with anterior cruciate ligament reconstruction (ACLR).

DESIGN

Two-arm, parallel-group randomized comparative design.

PATIENTS

A total of 100 amateur male athletes (mean age 22.01 ± 1.79 years) with ACLR were randomly divided into experimental and control groups (n = 50/group).

METHODS

An accelerated rehabilitation protocol and a conventional rehabilitation protocol were used for the experimental group. In contrast, only the conventional rehabilitation protocol was used for the control group. The rehabilitation was delivered in 5 weekly sessions for 22 weeks. The primary outcome measure, knee pain, was measured using a visual analogue scale (VAS). Extensive test batteries, for hop tests, Knee Injury and Osteoarthritis Outcome Score (KOOS), and knee effusion, were measured, aiming to add more objective criteria to determine functional performance.

RESULTS

Both groups (n = 50/group) were well-matched (p = 0.816), with insignificant differences in their demographic characteristics (p > 0.05). A multivariate analysis of variance (MANOVA) test showed no significant difference between the 2 groups (p = 0.781) at baseline. A 2-way MANOVA (2 × 2 MANOVA) of within- and between-group variations indicated overall significant treatment, time, and treatment × time interaction effects (p < 0.001) in favour of the accelerated rehabilitation group.

CONCLUSION

The accelerated rehabilitation protocol was more effective in improving functional outcomes than a conventional rehabilitation protocol in amateur athletes with ACLR.

In Situ Construction of Morphologically Different Hydroxyapatite-Mineralized Structures on a Three-Dimensional Bionic Chitin Scaffold

Slow healing at the tendon-bone interface is a prominent factor in the failure of tendon repair surgeries. The development of functional biomaterials with 3D gradient structures is urgently needed to improve tendon-bone integration. The crystalline form of hydroxyapatite (HAP) has a crucial impact on cell behavior, which directly influences protein adsorption, such as bone morphogenetic protein 2, the adhesion, proliferation, and osteogenic differentiation with cells. This work aimed to generate gradient mineral structures in situ by stabilizing calcium and phosphate ions using a polymer-induced liquid precursor process. To regulate the crystalline growth of HAP at the interface of β-chitin, this work made use of the surface properties of the organic matrix found in cuttlefish bone. These techniques allowed us to prepare an organic-inorganic composite gradient scaffold comprising plate-like HAP mineralized in situ on the surface of the scaffold and fibrous HAP in the scaffold's interior. Organic-inorganic composite gradient materials are anticipated for use in tendon-bone healing produced via the in situ construction of gradient-distributed HAP mineralization layers having varying crystalline morphologies on chitin scaffolds that possess a three-dimensional bionic structure.

Synovium-Derived Mesenchymal Stem Cell-Based Scaffold-Free Fibrocartilage Engineering for Bone-Tendon Interface Healing in an Anterior Cruciate Ligament Reconstruction Model

BACKGROUND

Current tendon and ligament reconstruction surgeries rely on scar tissue healing which differs from native bone-to-tendon interface (BTI) tissue. We aimed to engineer Synovium-derived mesenchymal stem cells (Sy-MSCs) based scaffold-free fibrocartilage constructs and investigate in vivo bone-tendon interface (BTI) healing efficacy in a rat anterior cruciate ligament (ACL) reconstruction model.

METHODS

Sy-MSCs were isolated from knee joint of rats. Scaffold-free sy-MSC constructs were fabricated and cultured in differentiation media including  TGF-β-only, CTGF-only, and TGF-β + CTGF. Collagenase treatment on tendon grafts was optimized to improve cell-to-graft integration. The effects of fibrocartilage differentiation and collagenase treatment on BTI integration was assessed by conducting histological staining, cell adhesion assay, and tensile testing. Finally, histological and biomechanical analyses were used to evaluate in vivo efficacy of fibrocartilage construct in a rat ACL reconstruction model.

RESULTS

Fibrocartilage-like features were observed with in the scaffold-free sy-MSC constructs when applying TGF-β and CTGF concurrently. Fifteen minutes collagenase treatment increased cellular attachment 1.9-fold compared to the Control group without affecting tensile strength. The failure stress was highest in the Col + D + group (22.494 ± 13.74 Kpa) compared to other groups at integration analysis in vitro. The ACL Recon + FC group exhibited a significant 88% increase in estimated stiffness (p = 0.0102) compared to the ACL Recon group at the 4-week postoperative period.

CONCLUSION

Scaffold-free, fibrocartilage engineering together with tendon collagenase treatment enhanced fibrocartilaginous BTI healing in ACL reconstruction.

Inline dynamometry provides reliable measurements of quadriceps strength in healthy and ACL-reconstructed individuals and is a valid substitute for isometric electromechanical dynamometry following ACL reconstruction

BACKGROUND

Quadriceps strength testing is recommended to guide rehabilitation and mitigate the risk of second injury following anterior cruciate ligament (ACL) reconstruction. Hand-held dynamometry is a practical alternative to electromechanical dynamometry but demonstrates insufficient reliability and criterion validity in healthy and ACL-reconstructed participants respectively. The purpose of this study is to investigate the reliability and concurrent validity of inline dynamometry for measuring quadriceps strength. The hypotheses are that intra-class correlation coefficient (ICC) values will be >0.90 for reliability and concurrent validity.

METHODS

This was a cross sectional study using a within-participant, repeated measures design. Isometric quadriceps testing was performed at 60° knee flexion in 50 healthy and 52 ACL-reconstructed participants. Interrater reliability, intrarater reliability, and concurrent validity of inline dynamometry was investigated through calculation of ICCs, Bland-Altman analysis, linear regression, standard error of measurement (SEM) and minimal detectable change (MDC).

RESULTS

The lower bounds of the 95% confidence intervals were >0.90 for all reliability and validity ICCs in healthy and ACL-reconstructed participants, except for intrarater reliability in healthy participants using absolute scores (ICC = 0.936 [95% CI 0.890-0.963]). In ACL-reconstructed participants, Bland-Altman bias was 0.01 Nm/kg for absolute and average scores, limits of agreement were -11.74% to 12.59% for absolute scores, the SEM was 0.13Nm/kg (95% CI 0.10-0.17) and the MDC was 0.36Nm/kg (95% CI 0.28 - 0.47).

CONCLUSION

Inline dynamometry is a reliable and economical alternative to electromechanical dynamometry for the assessment of quadriceps strength following ACL-reconstruction.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT05109871).

Lower Extremity Reaction Time in Individuals With Contact Versus Noncontact Anterior Cruciate Ligament Injuries After Reconstruction

CONTEXT

Deficits in perceptual-motor function, like visuomotor reaction time (VMRT), are risk factors for primary and secondary anterior cruciate ligament (ACL) injury. Noncontact ACL injuries have been associated with slower reaction time, but whether this association exists for patients with contact ACL injuries is unknown. Exploring differences in VMRT among individuals with contact versus noncontact ACL injuries may provide a more comprehensive understanding of modifiable risk factors.

OBJECTIVE

To compare lower extremity VMRT (LEVMRT) in individuals with contact or noncontact ACL injuries after ACL reconstruction (ACLR).

DESIGN

Cross-sectional study.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 36 participants with primary, unilateral ACLR completed an LEVMRT assessment (contact ACL injury = 20 [56%], noncontact ACL injury = 16 [44%]).

MAIN OUTCOME MEASURE(S)

The LEVMRT was assessed bilaterally and collected using a series of wireless light discs deactivated by individuals with their feet. The ACLR-active LEVMRT (ie, ACLR limb is deactivating lights) and ACLR-stable LEVMRT were compared using separate analyses of covariance to determine the association with contact or noncontact injury using time since surgery as a covariate.

RESULTS

After controlling for time since surgery, a difference and large effect size between groups was found for the ACLR-stable LEVMRT (P = .010; η2 = 0.250) but not for the ACLR-active (P = .340; η2 = 0.065) condition. The contact group exhibited slower ACLR-stable LEVMRT (521.7 ± 59.3 milliseconds) than the noncontact group (483.4 ± 83.9 milliseconds).

CONCLUSIONS

Individuals with contact ACL injury demonstrated a slower LEVMRT while their ACLR limb was stabilizing. The group differences during the ACLR-stable LEVMRT task might indicate deficits in perceptual-motor function when the surgical limb maintains postural control during a reaction time task. After ACLR, individuals with contact injuries may need additional motor learning interventions to enhance perceptual-motor functioning.

Internal brace augmentation reconstruction versus standard anterior cruciate ligament reconstruction: a randomised controlled clinical trial study protocol

INTRODUCTION

Anterior cruciate ligament (ACL) rupture is one of the most common knee injuries in sports, and the gold standard for treating ACL rupture is tendon graft reconstruction. Internal brace technology is being used nowadays for ligament repair; however, more relevant in vivo clinical evidence is required for using internal brace technology in ACL reconstruction (ACLR). We conducted a randomised controlled trial to investigate the clinical efficacy of internal brace technology in ACLR.

METHODS AND ANALYSIS

This randomised, parallel-controlled trial included patients with ACL rupture who underwent inpatient surgery at the Department of Orthopaedics, Xiangya Hospital, Central South University. Random number table method was used to assign the participants to either the test or the control group. The test group underwent ACLR using the internal brace technique, whereas the control group underwent standard ACLR. Uniform postoperative rehabilitation protocol was used for both the groups. Patient-reported outcomes included preoperative baseline and postoperative recovery at 1, 3, 6, 12 and 24 months. The primary outcome was International Knee Documentation Committee function from baseline (ACL rupture) to 6 months postoperatively. Secondary outcomes included (1) other patient outcome reporting metrics, Lysholm knee score, Knee Injury and Osteoarthritis Outcome Score and Visual Analog Scale; (2) the use of Kneelax3 knee stabiliser to assess knee stability; (3) occurrence of adverse events, such as graft refraction or symptomatic instability, postoperative infection and contralateral injury and (4) magnetic resonance images at 12 and 24 months after ACLR.

ETHICS AND DISSEMINATION

This trial was approved by the Medical Ethics Committee of the Xiangya Hospital of Central South University on 26 October 2021. Data will be published in peer-reviewed journals and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200057526.

Analyzing the Quality, Reliability, and Educational Value of ACL Rehabilitation Exercises on TikTok: A Cross-Sectional Study

Background

Videos relating to rehabilitation exercises for common injuries relevant to younger populations such as anterior cruciate ligament (ACL) tear receive high view counts on social media platforms such as TikTok.

Purpose/Hypothesis

The purpose of this study was to analyze the quality, reliability, and educational value of TikTok videos among the patient population for ACL injury. It was hypothesized that TikTok videos related to ACL rehabilitation exercises would lack quality, reliability, and educational value.

Study Design

Cross-sectional study.

Methods

TikTok was queried for relevant videos using the hashtags "#ACLrehab" and "#ACLexercises." For each included video, the type of uploader (general user or health care professional) was identified. In addition, the number of views, likes, shares, comments, and favorites for each included video was recorded, and the content of each video was graded using the DISCERN (a well-validated informational analysis tool) and the ACL exercise education score (ACLEES - a custom-designed tool for the evaluation of ACL-related exercises).

Results

A total of 111 videos with 5,520,660 cumulative views were included; the median number of views per video was 9801.0 (interquartile range [IQR], 3583.0-28,000.0). Of these videos, 84 and 27 were created by the general public and health care professionals, respectively. The videos collectively received 335,577 likes, 2969 comments, 22,856 favorites, and 6142 shares, with a median of 439 (IQR, 111-1374), 10 (IQR, 2.5-25.5), 54 (IQR, 18-172.5), and 12 (IQR, 2-36), respectively. The tabulated scores for the DISCERN and ACLEES between general users and health care professionals were all statistically nonsignificant. Health care professionals had a higher percentage of videos with a "very poor" DISCERN score in comparison with the general public (66.67% vs 53.57%, respectively).

Conclusion

The overall educational value of the TikTok videos related to ACL rehabilitation exercises was very poor. Health care professionals should be aware of the broad distribution of ACL rehabilitation exercise videos that are accessible on TikTok and raise awareness of the deficiencies of the platform as a medium for educational medical-related information.

Effects of exercise prehabilitation before anterior cruciate ligament reconstruction on functional outcomes during pre- and postoperative rehabilitation - protocol for a single-blinded randomised controlled trial

BACKGROUND

Although a benefit of preoperative training prior to anterior cruciate ligament (ACL) reconstruction is likely, there is no consensus on the optimal content (criteria-based programme), supervision (one-on-one guidance or self-administered training) and general setting of preoperative training after ACL injuries. The purpose of this trial is to investigate the efficacy of an individually adaptive, guided, structured and criteria-based preoperative rehabilitation programme in comparison to a non-guided and self-administered home training programme.

METHODS

The planned single-blinded randomised controlled trial study was approved by the ethics committee of the German Sport University on June 14, 2022 (ethics application no. 093/2022) and prospectively registered (DRKS-ID: DRKS00030312; date of registration: 26.09.2022). N = 114 participants between 16 and 60 years of age with a unilateral ACL rupture and scheduled ACL reconstruction with a hamstring or quadriceps tendon autograft will be randomly (block-randomisation, 1:1 allocation) and blinded assigned to one of two groups: intervention group (structured, criteria-based, guided prehabilitation training) and comparator group (non-guided, self-administered home training). After surgical reconstruction, patients of both groups participate in the same standard, functional measurement-guided, postoperative rehabilitation programme. Stepwise increasing the functional requirements of the assessments, all participants participate in testing at the day of anamnesis (t1), 1-7 days before surgical reconstruction (t2), day of surgical reconstruction (t3) and 30 (t4), 60 (t5), 90 (t6) and 180 (t7) days post-reconstruction. The primary outcome is the overall self-reported knee condition, assessed by the sum score of all sub-scales of the Knee injury and Osteoarthritis Outcome Score (KOOS). Secondary outcomes include functional outcomes (range of motion, knee flexors and extensors and plantar flexors strength/torque, functional postural control, jumping ability), workability and return to sport (RTS) (psychological readiness, RTS success).

DISCUSSION

The planned study targets to fill a gap in the evidence regarding effective designs of prehabilitation training before surgical ACL reconstruction. Potential difficulties that could affect the conduct of the study are lack of treatment adherence of the patients and high dropout.

TRIAL REGISTRATION

German Register of Clinical Trials DRKS-ID: DRKS00030312 . Registered on 26 September 2022.

Sex, military occupation and rank are associated with risk of anterior cruciate ligament injury in tactical-athletes

INTRODUCTION

Anterior cruciate ligament (ACL) injury is common within the US military and represents a significant loss to readiness. Since recent changes to operational tempo, there has not been an analysis of ACL injury risk. The aim of this retrospective cohort study was to evaluate military occupation, sex, rank and branch of service on ACL injury risk in the US military from 2006 to 2018.

METHODS

The Defense Medical Epidemiology Database was queried for the number of US tactical athletes with International Classification of Diseases diagnosis codes 717.83 (old disruption of ACL), 844.2 (sprain of knee cruciate ligament), M23.61 (other spontaneous disruption of ACL) and S83.51 (sprain of ACL of knee) on their initial encounter. Relative risk and χ2 statistics were calculated to assess sex and military occupation effects on ACL injury. A multivariable negative binomial regression model evaluated changes in ACL injury incidence with respect to sex, branch of service and rank.

RESULTS

The study period displayed a significant decrease in the ACL injury rate at 0.18 cases per 1000 person-years or relative decrease of 4.08% each year (p<0.001) after averaging over the main and interactive effects of sex, rank and branch of service. The interaction effect of time with sex indicated a steeper decline in the incidence in men as compared with women. The risk of ACL injury by sex was modified by rank. The incidence among military personnel varied by occupation.

CONCLUSION

Despite the decline among tactical athletes over time, rates of ACL injury remain much higher than the general US population. Sex, rank, branch of service and military occupation were found to be risk factors for ACL injury. It is critical for policy makers to understand the salient risk factors for ACL injury to guide proactive measures to prevent injury.

Physical inactivity 5-8 years after anterior cruciate ligament reconstruction is associated with knee-related self-efficacy and psychological readiness to return to sport

Objectives

To investigate whether patient demographics and patient-reported outcomes (PROs), respectively, are associated with physical inactivity (PI) 5-8 years after primary anterior cruciate ligament reconstruction (ACLR).

Methods

This case control observational study included individuals who had undergone primary ACLR between the ages of 15 and 65 years and had responded to PROs 18 months postoperatively. These individuals were asked to answer a questionnaire regarding their present level of physical activity (PA) at 5-8 years after ACLR. Patient-demographic data and results from the Knee injury and Osteoarthritis Outcome Score, the Knee Self-Efficacy Scale and the ACL Return to Sport (RTS) after Injury scale from 18 months after ACLR were extracted from a rehabilitation-specific register. Univariable logistic regression analyses were performed with PI (<150 min PA per week/≥150 min PA/week) as the dependent variable.

Results

Of 292 eligible participants, 173 (47% women; mean±SD age = 31±11 years) responded to the PA questionnaire. In all, 14% (n=25; 28% women) were classified as physically inactive. Participants with lower levels of present and future self-efficacy, OR 1.35 (CI 1.05 to 1.72) and OR 1.20 (CI 1.12 to 1.45), and lower levels of psychological readiness to RTS, OR 1.19 (CI 1 to 1.43), at the 18-month follow-up, had higher odds of being physically inactive 5-8 years after ACLR. None of the patient demographic variables was able to predict PI.

Conclusion

Lower levels of knee-related self-efficacy and psychological readiness to RTS, 18 months after ACLR, were associated with PI 5-8 years after surgery.

Clinical Utility of Ultrasound Imaging for Measuring Anterior Thigh Thickness after Anterior Cruciate Ligament Injury in an Individual Patient to Assess Postsurgery Outcome

The present study investigated the clinical utility of ultrasound imaging (USI) for assessing changes in an individual's quadriceps muscle and subcutaneous fat (SF) thickness of the anterior thigh and their relative proportions. A patient was studied prior to and after anterior cruciate ligament reconstruction (ACLR) surgery and during rehabilitation. This case study involved an 18-year-old female recreational athlete with a complete tear of the anterior cruciate ligament (ACL). Tissue thickness (SF and quadriceps muscle) was measured from transverse USI of the anterior thigh before surgery, at weekly intervals during 12 weeks of postsurgery, and then every 2 weeks for the following 12 weeks (total of 21 measurement sets). Statistically significant differences presurgery to postrehabilitation were found for muscle thickness (p = 0.04) and SF tissue thickness (p = 0.04) measurements. There was no difference in muscle to fat ratio (p = 0.08). Changes in measurements greater than the reported minimal detectable change (MDC) demonstrate the sensitivity of the USI technique as an objective tool to assess clinically useful changes in an individual's anterior thigh muscle thickness post-ACLR surgery and during rehabilitation.

Fatigue-induced Landing Alterations in ACL Reconstructed Athletes after Return-to-Sport

At the time of return-to-sport, anterior cruciate ligament reconstructed athletes still show altered neuromechanics in their injured leg during single leg hopping tasks. Part of these alterations can be magnified when these athletes are fatigued. So far, little is known whether fatigue-induced landing alterations persist after return-to-sport. Therefore, the aim of this study was to evaluate whether these alterations persist in the six months following return-to-sport. Sixteen anterior cruciate ligament reconstructed athletes performed five unilateral hop tasks before and after a fatigue protocol. The hop tasks were executed at three different time points (return-to-sport, 3 and 6 months post-return-to-sport). A 2-by-3 repeated measures ANOVA was performed to evaluate whether fatigue-induced landing alterations persisted 3 and 6 months following return-to-sport. At 6 months following return-to-sport, fatigue still induces a reduction in hamstring medialis activation and an increase in the knee abduction moment during a vertical hop with 90-degree inward rotation. Most fatigue-induced landing alterations present at the time of return-to-sport normalize after resumption of sports activities. However, a larger knee abduction moment in the injured leg after resumption of sports activities can still be observed.

Muscle function, Lysholm score and hop performance in individuals with clinical indications for the combined reconstruction of the anterior cruciate and the anterolateral ligaments of the knee: A cross-sectional study

OBJECTIVE

To evaluate hip and knee muscular function, knee patient-reported outcome measures and hop performance in patients with a clinical indication for combined ACL+ALL reconstruction surgery compared to patients with an isolated ACL reconstruction surgery indication (preoperative phase) and to a control group.

DESIGN

Cross-sectional study.

METHODS

The sample was composed of male individuals, aged between 18 and 59 years, divided into three groups (ACL, ACL+ALL and Control). Isokinetic dynamometry was performed for the flexor and extensor knee muscles and for the hip abductors and adductors. SLHT, COHT and the Lysholm score were performed. Pain, swelling, and thigh trophism were also measured.

RESULTS

The study participants were 89 male individuals: 63 in the injury group and 26 in the control group. After applying the criteria for an ALL reconstruction indication, 33 patients were assigned to the ACL Group and 30 patients to the ACL+ALL Group. Regarding knee and hip muscle function, both groups presented worse results when compared to the control group, however, did not show significant differences compared to each other. Regarding the functional variables, the ACL+ALL group showed a significantly shorter distance achieved in the Crossover Hop Test than the other groups, as well as more pain during the tests.

CONCLUSION

Knee and hip muscular functions are impaired after an ACL injury and do not seem to be influenced or worsened in individuals with greater rotational instability with clinical indications for combined reconstruction of the anterior cruciate and the anterolateral ligaments of the knee.

Reduced Incidence of Revision Anterior Cruciate Ligament Reconstruction With Internal Brace Augmentation

Background

Revision rates and outcome measures after anterior cruciate ligament reconstruction (ACLR) with suture tape as an internal brace is not well-documented because of the emerging nature of the technique.

Hypothesis

ACLR with internal bracing (IB) would lead to decreased revision ACLR compared with traditional ACLR while exhibiting comparable patient outcomes.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 200 patients were included in this study. Patients aged between 13 and 39 years at the time of surgery who underwent primary autograft ACLR with IB between 2010 and 2020 and were enrolled in our institution's registry with a minimum of 2-year follow-up were identified and matched 1 to 1 with a non-internal brace (no-IB) group based on concomitant procedures and patient characteristics. Pre- and postoperatively, patients completed the Knee injury and Osteoarthritis Outcome Score, Marx activity rating scale, Veterans RAND 12-Item Health Survey, and visual analog scale for pain. Knee laxity measurements via the KT-1000 arthrometer were included in the pre- and postoperative objective clinical assessments.

Results

A total of 100 IB patients were matched with 100 no-IB patients based primarily on concomitant procedures and secondarily on patient characteristics. The IB group underwent significantly fewer revision ACLRs (1% vs 8%; P = .017). Even though the no-IB group had a significantly longer mean final follow-up time (48.6 months [95% CI, 45.4-51.7] vs 33.4 months [95% CI, 30.3-36.5]; P < .001), the time elapsed from the original ACLR to the revision did not differ significantly between groups, and the mean ages for the IB and no-IB groups were comparable (19 vs 19.9 years). All postoperative patient-reported outcome scores between the 2 groups were comparable and significantly improved postoperatively except for the Marx score, which significantly decreased stepwise for both groups postoperatively. KT-1000 measurements significantly improved in both groups after surgery with the IB and no-IB cohorts yielding comparable results at the manual maximum pull (0.97 vs 0.65 mm).

Conclusion

ACLR with IB resulted in a significantly decreased risk of revision ACLRs while maintaining comparable patient-reported outcomes. Therefore, incorporating an internal brace into ACLR appears to be safe and effective within these study parameters.

Development of Anatomic Risk Factors for ACL Injuries: A Comparison Between ACL-Injured Knees and Matched Controls

BACKGROUND

Several tibiofemoral anatomic features have been repeatedly associated with increased anterior cruciate ligament (ACL) injury risk. Previous studies have highlighted age and sex differences among these anatomic risk factors, but little is known about the normal and pathologic development of these differences during skeletal maturation.

PURPOSE

To investigate differences in anatomic risk factors at various stages of skeletal maturation between ACL-injured knees and matched controls.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

After institutional review board approval, magnetic resonance imaging scans from 213 unique ACL-injured knees (age, 7-18 years, 48% female) and 239 unique asymptomatic ACL-intact knees (age, 7-18 years, 50% female) were used to measure femoral notch width, posterior slope of the lateral and medial tibial plateau, medial and lateral tibial spinal height (MTSH, LTSH), medial tibial depth, and posterior lateral meniscus-bone angle. Linear regression was performed to assess change in quantified anatomic indices with age for male and female patients in the ACL-injured cohort. Two-way analysis of variance with Holm-Sidak post hoc testing was performed to compare anatomic indices between ACL-injured knees and ACL-intact controls in each age group.

RESULTS

In the ACL-injured cohort, notch width, notch width index and medial tibial depth increased with age (R2 > 0.1; P < .001) in both sexes. MTSH and LTSH increased with age only in boys (R2≥ 0.09; P≤ .001), whereas meniscus-bone angle decreased with age only in girls (R2 = 0.13; P < .001). There were no other age differences in quantified anatomic indices. Patients with ACL injury consistently had a significantly higher lateral tibial slope (P < .01) and smaller LTSH (P < .001) as compared with ACL-intact controls across all age groups and sexes. When compared with age- and sex-matched ACL-intact controls, ACL-injured knees had a smaller notch width (boys, 7-18 years; girls, 7-14 years; P < .05), larger medial tibial slope (boys and girls, 15-18 years; P < .01), smaller MTSH (boys, 7-14 years; girls, 11-14 years; P < .05), and larger meniscus-bone angle (girls, 7-10 years; P = .050).

CONCLUSION

The consistent morphologic differences throughout skeletal growth and maturation suggest a developmental role in high-risk knee morphology. The observed high-risk knee morphology at an earlier age preliminarily suggests the potential of knee anatomy measurements in identifying those with a predisposition toward ACL injury.

Insurance cost and injury characteristics of anterior cruciate ligament injuries in sub-elite football: A population analysis involving 3 years of Australian insurance data

OBJECTIVES

To investigate the injury characteristics and insurance cost of anterior cruciate ligament injuries in sub-elite football players in New South Wales, Australia.

DESIGN

Descriptive epidemiological study.

METHODS

Three years of insurance records (2018-2020) was used to describe anterior cruciate ligament injury costs and characteristics. Concomitant injuries and the mechanism of injury were determined by analysing the injury descriptions. Claim characteristics and costs are presented by age group (junior = 7-17 years, senior = 18-34 years, and veteran = 35 + years) and sex. Categorical data (including age-groups and sex) are presented as counts and percentages and analysed using a Chi squared or Fisher's exact test. Cost data are reported as means ± standard deviation with 95 % confidence intervals.

RESULTS

Over the course of three football seasons (2018-2020), 786 anterior cruciate ligament injuries were reported to the injury insurance company. The total insurance cost was AU$3,614,742 with direct injury insurance costs accounting for 36.3 % of the total costs. The mean indirect insurance costs were six-fold higher than direct insurance costs (AU$11,458 vs AU$1914). Isolated injuries had an average cost of $4466 whilst concomitant injuries had an average cost of $4951. Surgical costs are excluded from direct cost calculations. The peak injury count occurred in the first month of all three football seasons, immediately after the pre-season.

CONCLUSIONS

Anterior cruciate ligament injuries represent a substantial economic burden to the insurer and individual. The cost data provided can be used for future economic and modelling studies.

Can patients and clinicians find conservative management protocols of anterior cruciate ligament injuries online? A systematic review

OBJECTIVE

To systematically search the internet for conservative rehabilitation protocols for people with an anterior cruciate ligament (ACL) injury and critically appraise the websites and exercise protocols.

DESIGN

Systematic review of online rehabilitation protocols.

SEARCH

We searched four online search-engines (Google, Yahoo, Bing, DuckDuckGo).

SELECTION CRITERIA

Rehabilitation protocols on active, English language websites aimed at conservative (non-surgical) management of an ACL injury.

DATA SYNTHESIS

We extracted descriptive information and assessed quality of the websites using the Journal of the American Medical Association (JAMA) benchmark criteria, the Health on the Net Code (HONcode) certificate, and the Flesch-Kincaid Reading Ease (FKRE). We assessed completeness of exercise protocol reporting using the Consensus on Exercise Reporting Template (CERT). We performed a descriptive analysis.

RESULTS

We found 14 websites that met our selection criteria. The protocols varied between 10 and 26 weeks duration, nine were from the United States, five targeted patients, and 13 used multiple phases with a variety of different criteria for progression. Three protocols scored good quality with the JAMA, two were HonCode certified, and ten had good readability according to the FKRE. Completeness of exercise protocol reporting in all but one protocol was poor according to the CERT.

CONCLUSION

Few rehabilitation protocols for conservative management of ACL injuries were available online. Most of the websites showed good readability, but poor quality and credibility with inadequate description of exercise protocols.

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 experience and influence of fear after anterior cruciate ligament reconstruction: an interview study with young athletes

BACKGROUND

Despite good physical function, many athletes do not return to sports after an anterior cruciate ligament reconstruction (ACLR). One important reason for this is fear of new injury. The aim of this study was to investigate young athletes' experiences of knee-related fear after an ACLR and how they perceive this fear to affect them in their sporting and everyday life.

METHODS

A qualitative interview study was conducted, using semi-structured interviews. Athletes who were active in contact or pivoting sport before an ACL injury, with the goal of returning to the same sport and who scored highly on fear of new injury at six months post-ACLR, were asked to participate. Ten athletes (six women and four men, aged 17-25 years), were interviewed by an independent researcher, 7-9 months after ACLR. Content analysis employing an abductive approach was used.

RESULTS

The analysis resulted in three categories with associated subcategories: 1. The expressions of fear; (i) reason for fear, (ii) changes in fear over time, and (iii) injury situation. 2. Reactions, consequences, and adaptations; (i) reactions, (ii) behavioural adaptation and influence on rehabilitation and daily life, (iii) present consequences, and (iv) consequences for the future. 3. Fear and adaptations related to returning to sports; (i) fear related to returning to sports and, (ii) adaptations in sports and life due to fear. Fear was described in broad and complex ways, with fear of a new injury being expressed as one of several aspects. Various reasons (e.g., seeing others getting injured in the past, previous experience of injury, failed rehabilitation, perceived knee instability) were given to explain the fear, and athletes reacted both physically and mentally to fear. Both positive and negative adaptations to fear were described, in both daily life and sports.

CONCLUSION

The results contribute to an increased understanding of fear as an essential psychological factor to consider during rehabilitation and leaves the way open for research to investigate how physiotherapists can work to manage fear better among ACLR patients.

Curves and kinematics: Relationship between the force-time curve and landing ability

Anterior cruciate ligament (ACL) injuries have a significant impact on athletic performance and long-term quality of life. Force plates and qualitative screening tools are feasible and effective screening methods to identify abnormal movement quality associated with increased injury risk. Comparing qualitative assessments of landing ability with force-time curves, may detect unique differences between safe and high-risk athletic movement patterns. The aim of this study was to determine low- and high-risk landing ability from qualitive landing assessments and to examine the resulting force-time curves using functional principal component analysis (fPCA). Thirty-one healthy academy athletes (10 males and 21 females) completed double- and single-leg dominant and non-dominant jump-landing-rebound tasks. All movements were filmed in multiple-planes, and vertical ground reaction forces (vGRF) were simultaneously collected. The Landing Error Scoring System (LESS) and Single-Leg Landing Error Scoring System (SL-LESS) were used to score landing footage. From these scores, athletes were categorized into low-risk and high-risk groups for further analysis. fPCA was used to examine differences between landing quality groups force-time curves. Compared to high-risk landers, low-risk landers demonstrated significantly longer contact times across all movements. Scores from fPC1 revealed safe and high-risk landing techniques expose athletes to significantly different loading patterns during double- and single-leg dominant movements. A significant positive relationship was observed between fPC1 and LESS scores, however this relationship was not observed in both single-leg landing scores. Where possible incorporating curve analysis methods like fPCA into multi-faceted screening approaches may help practitioners uncover unique insights into athletic loading strategies.

"Trends and beliefs in ACL reconstruction surgery: Indian perspectives"

Objectives

The survey aimed to assess trends and beliefs in the management of anterior cruciate ligament reconstruction (ACLR) amongst orthopaedic surgeons in India.

Methods

A survey was created and distributed among the various orthopaedic surgeons from India. The questionnaire included brief details of surgeons and their experience, clinical assessment, management strategies and the rehabilitation protocol.

Results

135 surgeons completed the survey. 35% of them were having experience of more than 12 years. A large number of surgeons were from government academic institutes (35.5%). The most common criteria for deciding about surgery was Clinical evaluation (94.8%). The most common graft choice was hamstring tendon (94%), and suspensory fixation on the femur side and interference screw on the tibial side (80%) is the most common fixation method. Almost two-thirds of surgeons in this survey use bracing to protect ACL graft in the initial phase.

Conclusion

We presented the preferences amongst the group of surgeons on the management of ACL injuries. Hamstring tendon graft remains the most preferred graft for ACL reconstruction. Further, the suspensory loop on the femoral side and interference screw on the tibial side are the preferred fixation method. This group of surgeons is conservative in terms of the timing of surgeries and post-operative bracing. Level of evidence Level V, Expert Opinion.

Suture-tape augmentation of anterior cruciate ligament reconstruction: a prospective, randomised controlled trial (STACLR)

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction aims to restore anteroposterior and rotatory stability to the knee following ACL injury. This requires the graft to withstand the forces applied during the process of ligamentisation and the rehabilitative period. We hypothesise that the use of suture tape augmentation of single bundle ACL reconstruction (ACLR) will reduce residual knee laxity and improve patient-reported outcomes at 2-year follow-up. We will conduct a 1:1 parallel arm single-centre randomised controlled trial comparing suture tape augmented ACLR to standard ACLR technique.

METHODS

The study design will be a parallel arm 1:1 allocation ratio randomised controlled trial. Sixty-six patients aged 18 and over waitlisted for primary ACLR will be randomised. Patients requiring osteotomy and extra-articular tenodesis and who have had previous contralateral ACL rupture or repair of meniscal or cartilage pathology that modifies the post-operative rehabilitation will be excluded. The primary outcome measure will be the side-to-side difference in anterior tibial translation (measured on the GNRB arthrometer) at 24 months post-surgery. GNRB arthrometer measures will also be taken preoperatively, at 3 months and 12 months post-surgery. Secondary outcomes will include patient-reported outcome measures (PROMs) collected online, including quality of life, activity and readiness to return to sport, complication rates (return to theatre, graft failure and rates of sterile effusion), examination findings and return to sport outcomes. Participants will be seen preoperatively, at 6 weeks, 3 months, 12 months and 24 months post-surgery. Participants and those taking arthrometer measures will be blinded to allocation.

DISCUSSION

This will be the first randomised trial to investigate the effect of suture-tape augmentation of ACLR on either objective or subjective outcome measures. The use of suture-tape augmentation in ACLR has been associated with promising biomechanical and animal-level studies, exhibiting equivalent complication profiles to the standard technique, with initial non-comparative clinical studies establishing possible areas of advantage for the technique. The successful completion of this trial will allow for an improved understanding of the in situ validity of tape augmentation whilst potentially providing a further platform for surgical stabilisation of the ACL graft.

TRIAL REGISTRATION

Australia New Zealand Clinical Trial Registry ACTRN12621001162808. Universal Trial Number (UTN): U1111-1268-1487. Registered prospectively on 27 August 2021.

Beyond guidelines: A qualitative clinical stakeholder study of optimal management of anterior cruciate ligament rehabilitation

AIMS

This study gathered expert perspectives in the management of anterior cruciate ligament (ACL) rehabilitation to explore current practice, variations in care and optimal management strategies.

MATERIALS AND METHODS

This was a qualitative semi-structured interview study. The participants' experiences were considered in terms of their roles as employees, managers, clinicians and professional gatekeepers. Purposive and snowball sampling were used to recruit physiotherapists and orthopaedic surgeons. Participants were included if they had a proven record in clinical management or research involving ACL patients. Persons were excluded if they could not speak English. Interviews were conducted in person, via skype or over the phone at a time convenient to the participant. Data was analysed using a framework analysis and critical realist approach.

RESULTS

Results included 24 interviews that were conducted with 19 physiotherapists and 5 surgeons. Themes of variation in current care and optimal care were explored including subthemes of patient centred practice, evidence based medicine, resources, self-management, multidisciplinary teamwork, training and expertise were explored. Participant's perceptions of current care were that it was a location 'lottery' that significantly varied for patients across the UK.

CONCLUSIONS

Stakeholders identified that optimal management should be patient centred and incorporate adequate equipment, specific training for physiotherapists and a closely communicating multidisciplinary team. Research is needed to explore cost effective models of optimal rehabilitation that include return to sport strategies.

Biomechanical Gender Differences in the Uninjured Extremity After Anterior Cruciate Ligament Reconstruction in Adolescent Athletes: A Retrospective Motion Analysis Study

Introduction Subsequent anterior cruciate ligament (ACL) injury is more common in the pediatric population and encompasses graft failure and subsequent contralateral tears. Females are at a higher risk. The purpose of the present study was to compare the knee valgus angles at initial contact, knee extension moments, anterior and lateral knee joint forces, hip flexion angles, hip adduction moments, and ankle inversion during the drop vertical test in the uninjured extremity between adolescent males and females who had previously undergone an anterior cruciate ligament reconstruction (ACLR). Methods This IRB-approved retrospective chart review included patients aged 8-18 years who were seen at the five to seven month postoperatively following ACL reconstruction. A total of 168 patients met our inclusion criteria (86 girls and 82 boys.) Using three-dimensional motion capture technology (CORTEX software, Motion Analysis Corp., Rohnert Park, CA), data were collected while the subject performed the drop vertical test over floor-mounted force plates (FP-Stairs, AMTI, Watertown, MA) under the direct supervision of a pediatric physical therapist. The Wilcoxon rank sum was used, and p < 0.05 was considered statistically significant. Results Females demonstrated a larger average knee joint extension moment (0.31 vs 0.28 N*m/kg, p = 0.0408), a larger anterior knee joint force at initial contact (3.51 vs. 2.79, N/kg, p = 0.0458), larger average hip flexion angle (41.50° vs. 35.99°, p = 0.0005), a smaller maximum hip adduction moment (0.92 vs. 1.16, N*m/kg, p = 0.0497), and a smaller average ankle inversion angle (5.08° vs. 6.41°, p = 0.03231). No significant differences were found regarding knee abduction angle or lateral knee joint force. Conclusions The biomechanical profile of the contralateral extremity varies significantly between the genders after ACLR. In the uninjured extremity, females may have larger hip flexion angles, smaller hip adduction moments, larger anterior knee joint forces, larger knee extension moments, and smaller ankle inversion angles as compared to males after ACLR. These findings may explain the higher incidence of subsequent contralateral injury in female adolescent athletes. Further work is required to develop a composite score that determines at-risk athletes.

Canine ACL reconstruction with an injectable hydroxyapatite/collagen paste for accelerated healing of tendon-bone interface

Healing of an anterior cruciate ligament (ACL) autologous graft in a bone tunnel occurs through the formation of fibrovascular scar tissue, which is structurally and compositionally inferior to normal fibrocartilaginous insertion and thus may increase the reconstruction failure and the rate of failure recurrence. In this study, an injectable hydroxyapatite/type I collagen (HAp/Col Ⅰ) paste was developed to construct a suitable local microenvironment to accelerate the healing of bone-tendon interface. Physicochemical characterization demonstrated that the HAp/Col Ⅰ paste was injectable, uniform and stable. The in vitro cell culture illustrated that the paste could promote MC3T3-E1 cells proliferation and osteogenic expression. The results of a canine ACL reconstruction study showed that the reconstructive ACL had similar texture and color as the native ACL. The average width of the tunnel, total bone volume, bone volume/tissue volume and trabecular number acquired from micro-CT analysis suggested that the healing of tendon-bone interface in experimental group was better than that in control group. The biomechanical test showed the maximal loads in experimental group achieved approximately half of native ACL's maximal load at 24 weeks. According to histological examination, Sharpey fibers could be observed as early as 12 weeks postoperatively while a typical four-layer transitional structure of insertion site was regenerated at 48 weeks in the experimental group. The injectable HAp/Col Ⅰ paste provided a biomimetic scaffold and microenvironment for early cell attachment and proliferation, further osteogenic expression and extracellular matrix deposition, and in vivo structural and functional regeneration of the tendon-bone interface.

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A stable and injectable HAp/Col I paste was designed, optimized and characterized.

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The paste was applied in ACL reconstruction with an established standard operation procedure.

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Provided the safety and efficacy evidence for ACL reconstruction, and healing of tendon-bone interface was accelerated.

Nano-calcium silicate mineralized fish scale scaffolds for enhancing tendon-bone healing

Tendon-bone healing is essential for an effective rotator cuff tendon repair surgery, however, this remains a significant challenge due to the lack of biomaterials with high strength and bioactivity. Inspired by the high-performance exoskeleton of natural organisms, we set out to apply natural fish scale (FS) modified by calcium silicate nanoparticles (CS NPs) as a new biomaterial (CS-FS) to overcome the challenge. Benefit from its “Bouligand” microstructure, such FS-based scaffold maintained excellent tensile strength (125.05 MPa) and toughness (14.16 MJ/m³), which are 1.93 and 2.72 times that of natural tendon respectively, allowing it to well meet the requirements for rotator cuff tendon repair. Additionally, CS-FS showed diverse bioactivities by stimulating the differentiation and phenotypic maintenance of multiple types of cells participated into the composition of tendon-bone junction, (e.g. bone marrow mesenchymal stem cells (BMSCs), chondrocyte, and tendon stem/progenitor cells (TSPCs)). In both rat and rabbit rotator cuff tear (RCT) models, CS-FS played a key role in the tendon-bone interface regeneration and biomechanical function, which may be achieved by activating BMP-2/Smad/Runx2 pathway in BMSCs. Therefore, natural fish scale -based biomaterials are the promising candidate for clinical tendon repair due to their outstanding strength and bioactivity.

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Nano-calcium silicate mineralized fish scale scaffold was first developed for tendon defect repair.

•CS-FS exhibited excellent mechanical properties superior to those of natural tendon.

•CS-FS showed diverse bioactivities by stimulating the differentiation of multiple types of cells.

•CS NPs accelerated tendon-bone interface tendon-bone healing enhancement and biomechanical recovery.

Strategies for promoting tendon-bone healing: Current status and prospects

Tendon-bone insertion (TBI) injuries are common, primarily involving the rotator cuff (RC) and anterior cruciate ligament (ACL). At present, repair surgery and reconstructive surgery are the main treatments, and the main factor determining the curative effect of surgery is postoperative tendon-bone healing, which requires the stable combination of the transplanted tendon and the bone tunnel to ensure the stability of the joint. Fibrocartilage and bone formation are the main physiological processes in the bone marrow tract. Therefore, therapeutic measures conducive to these processes are likely to be applied clinically to promote tendon-bone healing. In recent years, biomaterials and compounds, stem cells, cell factors, platelet-rich plasma, exosomes, physical therapy, and other technologies have been widely used in the study of promoting tendon-bone healing. This review provides a comprehensive summary of strategies used to promote tendon-bone healing and analyses relevant preclinical and clinical studies. The potential application value of these strategies in promoting tendon-bone healing was also discussed.

The reliability of lower limb 3D gait analysis variables during a change of direction to 90- and 135-degree manoeuvres in recreational soccer players

BACKGROUND

Several biomechanical outcomes are being used to monitor the risk of injuries; therefore, their reliability and measurement errors need to be known.

OBJECTIVE

To measure the reliability and measurement error in lower limb 3D gait analysis outcomes during a 90∘ and 135∘ change of direction (COD) manoeuvre.

METHODS

A test re-test reliability study for ten healthy recreational players was conducted at seven-day intervals. Kinematics (Hip flexion, adduction, internal rotation angles and knee flexion abduction angles) and kinetics (Knee abduction moment and vertical ground reaction force) data during cutting 90∘ and 135∘ were collected using 3D gait analysis and force platform. Five trials for each task and leg were collected. Standard error of measurement (SEM) and the intraclass correlation coefficient (ICC) were calculated from the randomised leg.

RESULT

The ICC values of the kinematics, kinetics, and vertical ground reaction force (VGRF) outcomes (90∘ and 135∘) ranged from 0.85 to 0.95, showing good to excellent reliability. The SEM for joint angles was less than 1.69∘. The VGRV showed a higher ICC value than the other outcomes.

CONCLUSION

The current study results support the use of kinematics, kinetics, and VGRF outcomes for the assessment of knee ACL risk in clinic or research. However, the hip internal rotation angle should be treated with caution since the standard measurement error exceeded 10% compared to the mean value. The measurement errors provided in the current study are valuable for future studies.

Effects of Gluteus Medius and Biceps Femoris Stimulation on Reduction of Knee Abduction Moment During a Landing Task

Anterior cruciate ligament injury prevention should focus primarily on reduction of the knee abduction moment (KAM) in landing tasks. Gluteus medius and hamstring forces are considered to decrease KAM during landing. The effects of different muscle stimulations on KAM reduction were compared using 2 electrode sizes (standard 38 cm2 and half size 19 cm2) during a landing task. Twelve young healthy female adults (22.3 [3.6] y, 1.62 [0.02] m, 50.2 [4.7] kg) were recruited. KAM was calculated under 3 conditions of muscle stimulation (gluteus medius, biceps femoris, and both gluteus medius, and biceps femoris) using 2 electrode sizes, respectively versus no stimulation during a landing task. A repeated-measures analysis of variance determined that KAM differed significantly among stimulation conditions and post hoc analysis revealed that KAM was significantly decreased in conditions of stimulating either the gluteus medius (P < .001) or the biceps femoris (P < .001) with the standard electrode size, and condition of stimulating both gluteus medius and biceps femoris with half-size electrode (P = .012) when compared with the control condition. Therefore, stimulation on the gluteus medius, the biceps femoris, or both muscles could be implemented for the examination of anterior cruciate ligament injury potential.

Physiotherapeutic approach to the preoperative period for the anterior cruciate ligament reconstruction: A systematic review

INTRODUCTION

The tearing of the anterior cruciate ligament (ACL) is one of the most common type of knee injury. Current evidence show that there are specific predictors for postoperative success in ACL injuries, but there is a limited number of studies on preoperative rehabilitation. Therefore, the goals of this review were to emphasize physiotherapy approaches to the preoperative period and to verify its effectiveness at the time the athlete returns to sport.

METHOD

We conducted a systematic search in these databases: Medline, Scielo, Lilacs, CINAHL, Web of Science, PeDro and Cochrane Library.

RESULTS

Our searches identified 553 occurences; of these, 511 titles and abstracts underwent triage after removal of duplicates. We identified 120 full texts for a stricter screening, amongst them, three studies included in the review for complying with the elegibility criteria.

CONCLUSION

Physiotherapic preoperative treatment exhibits weak evidence for strength gains and pain relief, as well as strong evidence of functional improvement compared to the control group. These results were reported 4 months after the ACLR, in average.

The Mechanism of Anterior Cruciate Ligament Injuries in the National Football League: A Systematic Video Review

Introduction Anterior cruciate ligament (ACL) injuries are common among American football athletes, although few studies have performed video analyses of ACL injuries to better understand the injury mechanism. This work aims to characterize the mechanism of ACL injury during professional football competitions using video analysis. We hypothesize that football-specific injury trends will emerge, including high rates of contact injuries and associations with shallow knee and hip flexion angles (0°-30°). Methods Videos of professional football players suffering ACL injuries from 2007 to 2016 were analyzed. Injured players were identified using the injured reserve (IR) lists of the National Football League (NFL), and videos were discovered via a systematic Google search. Descriptive statistics and frequency analyses were performed on all variables using the Statistical Package for the Social Sciences (SPSS) version 23.0 (IBM SPSS Statistics, Armonk, NY, USA). Results Of the 429 ACL injuries identified, 53 (12%) videos were available. Deceleration was the most common injury maneuver, present in 32 (60%) athletes. Thirty-one (58%) players suffered contact injuries. Twenty-eight (53%) injuries demonstrated valgus collapse of the knee, and 26 (49%) had neutral knee rotation. Defensive backs (26%) and wide receivers (23%) were the most frequently injured positions. Conclusion Overall, we found that most ACL injuries had preceding contact, deceleration, shallow hip and knee flexion, and heel strike, and subsequent valgus collapse and neutral knee rotation. This understanding of American football-specific ACL tear mechanisms could help direct the focus of future injury prevention training modalities.

Influence of platelet-rich plasma (PRP) analogues on healing and clinical outcomes following anterior cruciate ligament (ACL) reconstructive surgery: a systematic review

PURPOSE

To systematically review the effect of PRP on healing (vascularization, inflammation and ligamentization) and clinical outcomes (pain, knee function and stability) in patients undergoing ACL reconstruction and compare the preparation and application of PRP.

METHODS

Independent systematic searches of online databases (Medline, Embase and Web of Science) were conducted following PRISMA guidelines (final search 10th July 2021). Studies were screened against inclusion criteria and risk of bias assessed using Critical appraisal skills programme (CASP) Randomised controlled trial (RCT) checklist. Independent data extraction preceded narrative analysis.

RESULTS

13 RCTs were included. The methods of PRP collection and application were varied. Significant early increases in rate of ligamentization and vascularisation were observed alongside early decreases in inflammation. No significant results were achieved in the later stages of the healing process. Significantly improved pain and knee function was found but no consensus reached.

CONCLUSIONS

PRP influences healing through early vascularisation, culminating in higher rates of ligamentization. Long-term effects were not demonstrated suggesting the influence of PRP is limited. No consensus was reached on the impact of PRP on pain, knee stability and resultant knee function, providing avenues for further research. Subsequent investigations could incorporate multiple doses over time, more frequent observation and comparisons of different forms of PRP. The lack of standardisation of PRP collection and application techniques makes comparison difficult. Due to considerable heterogeneity, (I² > 50%), a formal meta-analysis was not possible highlighting the need for further high quality RCTs to assess the effectiveness of PRP. The biasing towards young males highlights the need for a more diverse range of participants to make the study more applicable to the general population.

TRAIL REGISTRATION

CRD42021242078CRD, 15th March 2021, retrospectively registered.

Association of Traumatic Knee Injury With Radiographic Evidence of Knee Osteoarthritis in Military Officers

OBJECTIVE

The association between knee injury and knee osteoarthritis (OA) is understudied relative to its importance, particularly in younger populations. This study was undertaken to examine the association of knee injury with radiographic features of knee OA in military officers, who have a physically demanding profession and high rates of knee injury.

METHODS

Participants were recruited in 2015-2017 from an existing program that enrolled 6,452 military officers during 2004-2009. Officers with a history of knee ligament or meniscal injuries (n = 117 via medical record review) were compared to officers with no history of knee injury (n = 143). Bilateral posteroanterior knee radiographs were obtained using a standardized fixed-flexion positioning frame. All images were read for Kellgren/Lawrence (K/L) grade, osteophyte (OST), and joint space narrowing (JSN) scores. Data were analyzed using linear-risk regression models with generalized estimating equations.

RESULTS

Injured and noninjured participants were similar (mean age 28 years, mean body mass index 25 kg/m² , ~40% female). The mean time from first knee injury to imaging among injured participants was 9.2 years. Compared with noninjured knees, greater prevalence of radiographic OA (K/L grade ≥ 2), OST (grade ≥ 1), and JSN (grade ≥ 1) was observed among injured knees, with prevalence differences of +16% (95% confidence interval [95% CI] 10%, 22%), +29% (95% CI 20%, 38%), and + 17% (95% CI 10%, 24%), respectively. Approximately 1 in 6 officers with prior knee injury progressed to radiographic OA by age 30 years.

CONCLUSION

At the midpoint of a projected 20-year military career, officers with a history of traumatic knee injury have a markedly increased prevalence of knee radiographic OA compared to officers without injury.

Double-bundle versus single-bundle anterior cruciate ligament reconstruction in preventing the progression of osteoarthritis: A protocol for systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The knee has a high incidence of osteoarthritis (OA) following the anterior cruciate ligament (ACL) injury, which was reduced by ACL reconstruction including double-bundle (DB) techniques and single-bundle (SB) techniques. However, the effectiveness of preventing the progression of OA after the ACL reconstruction using DB and SB techniques is controversial.

METHODS

This meta-analysis was performed following the preferred reporting items for systematic reviews and meta-analyses guidelines. The databases, including PubMed, Embase, and Cochrane Library, were searched. Randomized controlled trials comparing DB with SB ACL reconstruction and reporting clinical outcomes of radiological OA were included. Quality of the included studies was assessed using the Cochrane Collaboration's risk of bias tool. The outcome was analyzed using the risk ratio (RR) and its corresponding 95% confidence interval (CI).

RESULTS

Ten Randomized controlled trials studies were included in this meta-analysis (accounting 1062 knees: 475 SB and 587 DB). The rate of radiological OA after the ACL reconstruction was 39% in SB group and 34% in DB group. The results of meta-analysis showed no difference in the occurrence of radiological OA between DB group and in SB group (RR, 1.05; 95% CI, 0.85-1.30, P = .63), including subgroup of radiological scores of OA (subgroup of Minimal OA: RR, 0.95; 95% CI, 0.61-1.48; P = .82; subgroup of Notable OA: RR, 1.16; 95% CI, 0.75-1.78; P = .51), subgroup of follow-up time in 5 years and more than 5 years (RR, 0.98; 95% CI, 0.80-1.20; P = .85), and subgroup of autograft graft for ACL (RR, 0.97; 95% CI, 0.79-1.19; P = .77). However, the DB group had less incidences of knee OA than the SB group in subgroup of less than 5 years (RR, 1.48; 95% CI, 1.13-1.92; P = .004) and subgroup of allograft type (RR, 1.42; 95% CI, 1.06-1.91; P = .02).

CONCLUSION

Overall, this meta-analysis showed that the DB technique was no more effective in preventing the progression of OA than the SB technique in ACL reconstruction at midterm follow-up.