Major Increase in Incidence of Pediatric ACL Reconstructions From 2005 to 2021: A Study From the Norwegian Knee Ligament Register

The gender and sex data gap in anterior cruciate ligament injuries in paediatric patients

Anterior cruciate ligament (ACL) injury is a concerning problem in the paediatric population, impacting joint health and longevity. Moreover, ACL injury hampers physical activity, which is important for children's social network and general well-being. Recent data demonstrates a rise in paediatric ACL reconstructions, affecting both girls and boys. However, it is unclear whether this rise reflects a higher injury rate or a more proactive approach towards surgery, as information on nonoperated patients is lacking. Regarding gender differences, increasing evidence implies that girls engaged in pivoting sports experience a higher incidence of ACL injuries and reinjuries compared to boys. Furthermore, data suggest that girls have inferior outcomes and lower return-to-sport rates than boys. The social context in which girls compete in sports is likely a significant contributing factor to the risk of serious knee injuries. Lack of attention and insufficient data on gender-based differences in ACL injuries, outcomes and evidence-based treatment guidelines highlight the need for further research on this topic. LEVEL OF EVIDENCE: Level IV.

Surgical parameters influence paediatric knee kinematics and cartilage stresses in anterior cruciate ligament reconstruction: Navigating subject-specific variability using neuromusculoskeletal-finite element modelling analysis

PURPOSE

Anterior cruciate ligament (ACL) rupture is increasingly common in paediatric and adolescent populations, typically requiring surgical ACL reconstruction (ACLR) to restore knee stability. However, ACLR substantially alters knee biomechanics (e.g., motion and tissue mechanics) placing the patient at elevated risk of early-onset knee osteoarthritis.

METHODS

This study employed a linked neuromusculoskeletal (NMSK)-finite element (FE) model to determine effects of four critical ACLR surgical parameters (graft type, size, location and pre-tension) on tibial articular cartilage stresses in three paediatric knees of different sizes during walking. Optimal surgical combinations were defined by minimal kinematic and tibial cartilage stress deviations in comparison to a corresponding intact healthy knee, with substantial deviations defined by normalized root mean square error (nRMSE) > 10%.

RESULTS

Results showed unique trends of principal stress deviations across knee sizes with small knee showing least deviation from intact knee, followed by large- and medium-sized knees. The nRMSE values for cartilage stresses displayed notable variability across different knees. Surgical combination yielding the highest nRMSE in comparison to the one with lowest nRMSE resulted in an increase of maximum principal stress on the medial tibial cartilage by 18.0%, 6.0% and 1.2% for small, medium and large knees, respectively. Similarly, there was an increase of maximum principal stress on lateral tibial cartilage by 11.2%, 4.1% and 12.7% for small, medium and large knees, respectively. Knee phenotype and NMSK factors contributed to deviations in knee kinematics and tibial cartilage stresses. Although optimal surgical configurations were found for each knee size, no generalizable trends emerged emphasizing the subject-specific nature of the knee and neuromuscular system.

CONCLUSION

Study findings underscore subject-specific complexities in ACLR biomechanics, necessitating personalized surgical planning for effective restoration of native motion and tissue mechanics. Future research should expand investigations to include a broader spectrum of subject-specific factors to advance personalized surgical planning.

LEVEL OF EVIDENCE

Level III.

Investigating the Bone Bruise Patterns in Pediatric Patients With Contact and Noncontact Acute Anterior Cruciate Ligament Tears: A Multicenter Study

BACKGROUND

In adults with anterior cruciate ligament (ACL) tears, bone bruises on magnetic resonance imaging (MRI) scans provide insight into the underlying mechanism of injury. There is a paucity of literature that has investigated these relationships in children with ACL tears.

PURPOSE

To examine and compare the number and location of bone bruises between contact and noncontact ACL tears in pediatric patients.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Boys ≤14 years and girls ≤12 years of age who underwent primary ACL reconstruction surgery between 2018 and 2022 were identified at 3 separate institutions. Eligibility criteria required detailed documentation of the mechanism of injury and MRI performed within 30 days of the initial ACL tear. Patients with congenital lower extremity abnormalities, concomitant fractures, injuries to the posterolateral corner and/or posterior cruciate ligament, previous ipsilateral knee injuries or surgeries, or closed physes evident on MRI scans were excluded. Patients were stratified into 2 groups based on a contact or noncontact mechanism of injury. Preoperative MRI scans were retrospectively reviewed for the presence of bone bruises in the coronal and sagittal planes using fat-suppressed T2-weighted images and a grid-based mapping technique of the tibiofemoral joint.

RESULTS

A total of 109 patients were included, with 76 (69.7%) patients sustaining noncontact injuries and 33 (30.3%) patients sustaining contact injuries. There were no significant differences between the contact and noncontact groups in terms of age (11.8 ± 2.0 vs 12.4 ± 1.3 years; P = .12), male sex (90.9% vs 88.2%; P > .99), time from initial injury to MRI (10.3 ± 8.1 vs 10.4 ± 8.9 days; P = .84), the presence of a concomitant medial meniscus tear (18.2% vs 14.5%; P = .62) or lateral meniscus tear (69.7% vs 52.6%; P = .097), and sport-related injuries (82.9% vs 81.8%; P = .89). No significant differences were observed in the frequency of combined lateral tibiofemoral (lateral femoral condyle + lateral tibial plateau) bone bruises (87.9% contact vs 78.9% noncontact; P = .41) or combined medial tibiofemoral (medial femoral condyle [MFC] + medial tibial plateau) bone bruises (54.5% contact vs 35.5% noncontact; P = .064). Patients with contact ACL tears were significantly more likely to have centrally located MFC bruising (odds ratio, 4.3; 95% CI, 1.6-11; P = .0038) and less likely to have bruising on the anterior aspect of the lateral tibial plateau (odds ratio, 0.27; 95% CI, 0.097-0.76; P = .013).

CONCLUSION

Children with contact ACL tears were 4 times more likely to present with centrally located MFC bone bruises on preoperative MRI scans compared with children who sustained noncontact ACL tears. Future studies should investigate the relationship between these bone bruise patterns and the potential risk of articular cartilage damage in pediatric patients with contact ACL tears.

Sex-Specific Outcomes After Anterior Cruciate Ligament Reconstruction Using an All-Soft Tissue Quadriceps Tendon Autograft in a Young Active Population

BACKGROUND

The ideal graft for anterior cruciate ligament (ACL) reconstruction (ACLR) in young athletes has a high return-to-sport (RTS) rate and a low reinjury rate. Quadriceps tendon autografts are being used with increasing frequency for ACLR in this population, despite a paucity of evidence to support their use.

PURPOSE

To report the RTS rate, ipsilateral reinjury rate, and contralateral ACL injury rate in a young athletic population undergoing primary ACLR using an all-soft tissue quadriceps tendon (ASTQT) autograft.

STUDY DESIGN

Cases series; Level of evidence, 4.

METHODS

Patients aged 14 to 22 years who underwent primary ACLR using an ASTQT autograft by a single surgeon between January 1, 2005, and April 30, 2020, were identified via electronic medical records and contacted ≥24 months after ACLR to complete a survey regarding subsequent ipsilateral or contralateral ACL injuries and RTS. Patients who had undergone previous ACLR (ipsilateral or contralateral) were excluded.

RESULTS

A total of 656 patients (330 male, 326 female; mean age, 17.9 years) were identified, and 395 patients completed the survey (60.2%; 174 male, 221 female; mean age, 17.8 years) with a mean follow-up of 73 ± 29 months (range, 24-139 months). The RTS rate was high (male: 87.7%; female: 82.8%; P = .19). Male and female patients had similar rates of revision ACLR (male: 12.6%; female: 10.0%; P = .40) and contralateral ACL injuries (male: 13.8%; female: 11.3%; P = .46).

CONCLUSION

A high RTS rate and similar rates of ipsilateral and contralateral ACL injuries were found for male and female patients in a young athletic population undergoing primary ACLR using an ASTQT autograft. These results help one to better understand the utility of ASTQT grafts to support successful ACLR in young athletic populations, for which ASTQT grafts appear to yield favorable outcomes.

The posterior condyle grows in the direction of the increasing posterior condylar offset and the inclination angle of the ACL changes accordingly

PURPOSE

The purpose of this study was to reveal the changes in the shape of the posterior femoral condyle and the morphology of the ACL, both before and after epiphyseal closure. The hypothesis of this study is that the morphological change of the posterior femoral condyle and that of the ACL may be correlated to some extent.

METHODS

Eighty-one patients who underwent surgery for the knee joint (meniscal repair, arthroscopic synovectomy, medial patellofemoral ligament reconstruction) between 2016 and 2021 were included in this study, 48 patients aged 13 years or under (before epiphysis closure; mean age: 10.9 (range: 7-13) and 33 patients aged over 18 years or over (after epiphysis closure; mean age: 21.7 (range: 18-30). The shape of the posterior femoral condyle was evaluated via lateral view radiographs, and the morphology of the ACL was measured via sagittal and coronal magnetic resonance imaging (MRI) images.

RESULTS

The morphology of the posterior condyle in the lateral view radiograph in patients aged 13 and under was larger in the direction of the short axis of the femur compared with that in those aged 18 and over (p < 0.001). The mean value of the inclination angle of the anterior cruciate ligament (ACL) in the sagittal plane was significantly smaller in patients aged 13 and under (41.7° ± 3.7) than in those aged 18 and over (48.5° ± 4.2) (p < 0.001). The mean values of the inclination angle of the ACL in the coronal plane were significantly smaller in patients aged 13 and under (55.7° ± 6.4) than in those aged 18 and over (63.4° ± 4.4) (p < 0.001).

CONCLUSION

This study evaluates and compares the shape of the posterior femoral condyle and the morphology of the ACL fiber before and after epiphyseal closure. The posterior femoral condyle grew posteriorly rather than longitudinally, and the inclination of the ACL fibers was thought to change accordingly.

LEVEL OF EVIDENCE

Level Ⅲ.

Functional anterior cruciate ligament braces may have a role in select patient groups although there is presently limited evidence supporting or refuting their routine use: A scoping review of clinical practice guidelines and an updated bracing classification

PURPOSE

The purpose of this study was to perform a scoping review of clinical practice guidelines (CPGs) concerning the use of functional anterior cruciate ligament (ACL) braces and to clarify the nomenclature for bracing relevant to ACL injury treatment in order to support prescribing clinicians.

METHODS

A PubMed search for CPGs for the use of braces following ACL injury or reconstruction was performed. CPGs on the treatment of ACL injuries with sufficient attention to postoperative braces were included in this scoping review. The references used for supporting the specific CPG recommendations were reviewed. Specific indications for brace use including brace type, period of use following surgery and activities requiring brace use were collected.

RESULTS

Six CPGs were identified and included this this review. Three randomised trials provided the evidence for recommendations on functional brace use following ACL reconstruction in the six CPGs. Functional ACL braces were the primary focus of the three randomised trials, although extension braces (postoperative knee immobilisers) were also discussed. A novel dynamic ACL brace category has been described, although included CPGs did not provide guidance on this brace type.

CONCLUSIONS

Guidance on the use of functional ACL braces following ACL reconstruction is provided in six CPGs supported by three randomised trials. However, the brace protocols and patient compliance in the randomised trials render these CPGs inadequate for providing guidance on the use of functional ACL braces in the general and high-risk patient populations when returning to sport after ACL reconstruction. Functional ACL braces are commonly utilised during the course of ACL injury treatment although there is presently limited evidence supporting or refuting the routine use of these braces. Future studies are, therefore, necessary in order to provide guidance on the use of functional and dynamic ACL braces in high-risk patient populations.

LEVEL OF EVIDENCE

Level II.

Four distinct patterns of anterior cruciate ligament injury in women's professional football (soccer): a systematic video analysis of 37 match injuries

BACKGROUND

To identify mechanisms and patterns of anterior cruciate ligament (ACL) injury in adult women's professional football by means of video match analysis.

METHODS

ACL match injuries sustained in Germany's first women's league during the 2016-2017 to 2022-2023 seasons were prospectively analysed by three expert raters using a standardised observation form. Epidemiological and injury data, as well as the medical history of ACL tears, were obtained from media reports and the statutory accident insurance for professional athletes.

RESULTS

Thirty-seven ACL injuries sustained in official football matches were included in the video analysis, of which 24 (65%) had associated knee injuries, mainly meniscus and collateral ligament injuries. According to the categorised contact mechanisms, 17 (46%) were non-contact injuries, 14 indirect contact injuries (38%) and six direct contact injuries (16%). Of the 17 non-contact injuries, seven (41%) occurred during the first 15 min of the match. Contact mechanisms did not differ between primary and secondary ACL injuries to the same or the contralateral side. Most injuries (80%) of field players occurred during horizontal movements such as sprinting (n=9, 26%), change-of-direction manoeuvres (n=7, 19%), stopping (n=5, 14%) and lunging (n=5, 14%). Four distinct repetitive patterns of ACL match injuries were identified: (1) non-contact 'pressing ACL injury' (n=9), (2) indirect contact 'parallel sprinting and tackling ACL injury' (n=7), (3) direct contact 'knee-to-knee ACL injury' (n=6) and (4) non-contact 'landing ACL injury' (n=4).

CONCLUSION

Most of the identified patterns of ACL injuries in women's professional football have great potential for prevention.

Global overview of anterior cruciate ligament reconstruction in children and adolescents over the past 20 years: a bibliometric analysis

OBJECTIVES

The objectives of this paper is to conduct a bibliometric analysis to examine the research status and development trend of anterior cruciate ligament injury and reconstruction in children and adolescents over the past 20 years.

DESIGN

Descriptive Research.

METHODS

This study obtained information regarding studies on Anterior Cruciate Ligament Reconstruction in Children and Adolescents from the Web of Science Core Collection database. Visual and bibliometric analysis were conducted using VOSviewer, Origin 2022, Pajek64 5.18and Excel 2019. These analytic tools facilitated the analysis of various aspects, including countries/regions, institutions, authors, journals and keywords related to the research.

RESULTS

From 2003 to 2023, a total of 1328 articles were retrieved in WOS, and 637 articles were selected by two authors. The most productive institutions are Childrens Hosp Philadelphia, Kocher, ms. Their articles have the highest number of publications and citations. The American journal of sports medicine is the most frequently cited journal for articles on anterior cruciate ligament reconstruction in children and adolescents. The most common keywords used in these articles were "anterior cruciate ligament reconstruction", "injury, children, adolescent", and "skeletally immature patients".

CONCLUSIONS

This study provides valuable insights into the research focus of anterior cruciate ligament reconstruction in children and adolescents. In recent years, there has been significant attention paid to areas of "the return to sport, re-repture rate and functional recovery after anterior cruciate ligament reconstruction" in this specific population. These aspects have emerged as key directions for future research in this field.

Sensitivity analysis of paediatric knee kinematics to the graft surgical parameters during anterior cruciate ligament reconstruction: A sequentially linked neuromusculoskeletal-finite element analysis

BACKGROUND AND OBJECTIVE

Incidence of paediatric anterior cruciate ligament (ACL) rupture has increased substantially over recent decades. Following ACL rupture, ACL reconstruction (ACLR) surgery is typically performed to restore passive knee stability. This surgery involves replacing the failed ACL with a graft, however, surgeons must select from range of surgical parameters (e.g., type, size, insertion, and pre-tension) with no robust evidence guiding these decisions. This study presents a systemmatic computational approach to study effects of surgical parameter variation on kinematics of paediatric knees.

METHODS

This study used sequentially-linked neuromusculoskeletal (NMSK) finite element (FE) models of three paediatric knees to estimate the: (i) sensitivity of post-operative knee kinematics to four surgical parameters (type, size, insertion, and pre-tension) through multi-input multi-output sensitivity analysis; (ii) influence of motion and loading conditions throughout stance phase of walking gait on sensitivity indices; and (iii) influence of subject-specific anatomy (i.e., knee size) on sensitivivty indices. A previously validated FE model of the intact knee for each subject served as a reference against which ACLR knee kinematics were compared.

RESULTS

Sensitivity analyses revealed significant influences of surgical parameters on ACLR knee kinematics, albeit without discernible trend favouring any one parameter. Graft size and pre-tension were primary drivers of variation in knee translations and rotations, however, their effects fluctuated across stance indicating motion and loading conditions affect system sensitivity to surgical parameters. Importantly, the sensitivity of knee kinematics to surgical parameter varied across subjects, indicating geometry (i.e., knee size) influenced system sensitivity. Notably, alterations in graft parameters yielded substantial effects on kinematics (normalized root-mean-square-error > 10 %) compared to intact knee models, indicating surgical parameters vary post-operative knee kinematics.

CONCLUSIONS

Overall, this initial study highlights the importance of surgical parameter selection on post-operative kinematics in the paediatric ACLR knee, and provides evidence of the need for personalized surgical planning to ultimately enhance patient outcomes.

Epidemiology and distribution of cruciate ligament injuries in children and adolescents, with an analysis of risk factors for concomitant meniscal tear

Introduction

To investigate the epidemiological features and prevalence of cruciate ligament injuries (CLI) in children and adolescents, and to examine the potential risk factors associated with concomitant meniscal tear (MT) among this population.

Methods

The demographic data and injury details of children and adolescents with CLI from Southeast China were analyzed to describe their distribution characteristics, alongside an analysis of the prevalence of MTs, the most frequent complication. In addition, binary logistic analysis was employed to ascertain the risk factors linked to MT in individuals suffering from CLI.

Results

A total of 203 patients with CLI (n = 206) met the inclusion criteria, with a male-to-female ratio of 2.3:1. Notably, a higher proportion of females were aged ≤16 years old compared to males, who predominated in patients aged >16 years (P = 0.001). Among children and adolescents, anterior cruciate ligament (ACL) injuries were the primary type of CLI, accounting for 88.18% (179/203) of all cases. The majority of cases (132/203, 65.02%) were sustained during sports activities, and sprains were the predominant mechanism of injury (176/203, 86.7%). Additionally, the most common associated injury was an MT (157/203, 77.34%). The posterior horn is the most frequently affected site for both medial MT (62.93% out of 73 cases) and lateral MT (70.19% out of 73 cases). Moreover, vertical tears constituted the majority of medial MTs (59.48% out of 116 cases). Furthermore, patients with a higher BMI faced an increased risk of associated MT in comparison to non-overweight patients (88% vs. 73.86%; P = 0.038). Each increase in BMI unit was linked with a 14% higher probability of associated MT occurrence in children and adolescents with CLI (OR = 1.140; P = 0.036).

Discussion

ACL injuries are a common form of knee ligament injury among children and adolescents, especially those over the age of 16, and are often the result of a sprain. Meniscal posterior horn injury is the most commonly associated injury of youth with CLI. Additionally, overweight or obese people with CLI are at a greater risk of developing MT.

Anterior cruciate ligament reconstruction in skeletally immature patients is effective: A systematic review

PURPOSE

The present study evaluated the outcomes of anterior cruciate ligament (ACL) reconstruction in children with open physes. The outcomes of interest were to compare the increase in joint laxity and PROMs from baseline to the last follow-up, the rate and features of the return to sport and the rate of complications.

METHODS

This study was conducted according to the 2020 PRISMA guidelines. In October 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar and Embase. All the clinical studies investigating ACL reconstruction in skeletally immature patients were accessed. Only articles which clearly stated that surgeries were conducted in children with open physis were eligible.

RESULTS

Data from 53 studies (1691 procedures) were collected. 35% (597 out of 1691 patients) were women. The mean length of the follow-up was 44.7 ± 31.3 months. The mean age of the patients was 12.7 ± 1.1 years old. All PROMs significantly improved from the baseline values to those at the last follow-up. The mean time to return to sport was 8.3 ± 1.9 months. 89% (690 out of 771 patients) returned to sports, 15% (109 out of 721 patients) reduced their level of sports activity or league, and 84% (651 out of 771 patients) returned to their previous level of sport. 9% (112 out of 1213) of patients experienced re-tear of the reconstructed ACL, and 11% (75 out of 660) of patients underwent a further ACL reoperation. No patients (0 out of 83) demonstrated increased laxity at the last follow-up, and persistent sensation of instability was reported by 5% (11 out of 235) of patients.

CONCLUSION

ACL reconstruction in skeletally immature patients is effective and safe, and is associated with fast recovery and a high rate of return to sport.

LEVEL OF EVIDENCE

Level IV.

An Overview of Pediatric Knee Arthroscopy With Use of the NeedleScope

As sports-related injuries are becoming more common among children, there has been an increased need for knee arthroscopies in the pediatric population. Nevertheless, pediatric knee arthroscopy exposure is varied among orthopaedic surgeons, especially during residency training. There is a considerable difference in knee arthroscopy case volume between the adult and the pediatric population among orthopaedic residents. Although the fundamentals of adult knee arthroscopy have been well delineated, there is a paucity of literature surrounding basic pediatric knee arthroscopy. Our goal is to further explain the fundamentals needed to perform successful arthroscopic surgery in the pediatric knee. Through discussing proper patient positioning, instrumentation, including the utility of the 1.9-mm small-bore needle arthroscope (NanoScope; Arthrex, Naples, FL), subtle tips and tricks, as well as advantages and disadvantages of arthroscopy in children, this Technical Note along with the corresponding video are designed to help elucidate the intricacies of the pediatric knee. It will serve as educational material targeted to the resident trainee or any orthopaedic practitioner interested in gaining an introductory foundation to pediatric knee arthroscopy.