Prevention and screening programs for anterior cruciate ligament injuries in young athletes: a cost-effectiveness analysis

Decline in Pediatric Anterior Cruciate Ligament Reconstructions Seen Over 20 Years in the American Board of Orthopaedic Surgeons Part II Oral Examination Database

INTRODUCTION

Although increased treatment of pediatric anterior cruciate ligament (ACL) injury is well-documented, surrounding trends remain unknown. We evaluated national trends over 21 years using data from pediatric ACL reconstructions (ACLR) submitted to the American Board of Orthopaedic Surgeons (ABOS) Part II Oral Examination and compared fellowship training, geographic variation, and case volume trends.

METHODS

The ABOS SCRIBE database was queried for ACLR in pediatric (<19) patients between 2000 and 2021. Data included geographic region, fellowship training, and patient demographics. ACLRs per capita was estimated using census data. Data were stratified by age and sex. Multiple linear regression assessed whether year, sex, and age/sex category predicted surgery number.

RESULTS

From 2000 to 2021, ABOS Part II candidates reported 12,124 pediatric ACLR. Nearly 2/3 were in patients 16 years or older. Most were in the Midwest (22.8%) and South (22.2%). Each region decreased in ACLR. Overall, pediatric ACLR decreased 31.3% and contributing surgeons decreased 40.4%. Female ACLR increased 39.5% from 2009 to 2014, with 11.9% more than male patients in 2014. After 2014, sex differences and total ACLR decreased. 81.3% were reported by surgeons with sports medicine training and 6.0% with dual sports medicine and pediatric orthopaedics fellowships. Dual training increased in 2009 and declined after 2013. Surgeries in male patients compared with female patients (B = -6.777, 95% confidence interval, -9.534 to -4.279) and male patients 16 to 18 years compared with male patients younger than 16 years (B = -4.935, 95% confidence interval, -6.596 to -3.273) decreased.

CONCLUSION

Pediatric ACLR performed by ABOS Part II candidates decreased overall, but a concern for increased ACLR in female patients persists. More surgeries were done in the Midwest and South.

STUDY DESIGN

Cross-sectional Study Level of Evidence: III.

Outcomes of a randomized controlled trial of neuromuscular training with real-time biofeedback in young female athletes

BACKGROUND

A large body of scientific work has been focused on reducing the high incidence rate of anterior cruciate ligament (ACL) injuries in young female compared to male soccer players. The purpose of this study was to determine the effects of a randomized clinical trial to reduce a risk factor of ACL injuries, knee abduction moment (KAM), with neuromuscular training and biomechanical biofeedback in adolescent female athletes.

METHODS

A prospective, randomized, active comparator, open blinded, end-point trial was conducted with 150 (age: 13.3 ± 2.2 yrs, height: 156.1 ± 1 0.6 cm, mass: 50.2 ± 11.3 kg) female soccer players. Each participant received neuromuscular training and randomized into one of three arms: 1) an active control, considered sham biofeedback (NMT), 2) a knee-focused biofeedback group (NMT + K), and 3) a hip-focused biofeedback group (NMT + H). The participants completed two assessments: a baseline session prior to the intervention and a post-intervention session. The primary outcome measure was change knee abduction moment during a double leg drop vertical jump (DVJ). Additionally, an unplanned single leg cutting task was also recorded. As an exploratory outcome measure, athletic exposures and ACL injuries were recorded weekly for six months following the post-test session.

RESULTS

A statistically significant reduction in KAM, during the DVJ, was found in all three intervention groups from baseline to the post-test (p < 0.05). However, statistically significant improvements in KAM during cutting was only observed in the NMT + H intervention group (p < 0.05). ACL injuries were not reported in any intervention group during the six months of follow up.

CONCLUSIONS

While female soccer players involved in neuromuscular training programs regardless of intervention group exhibit significant improvements in KAM during a double leg landing, those that engage in hip-focused biofeedback compared to knee-focused or sham biofeedback exhibit decreased KAM during an unanticipated cutting maneuver.

TRIAL REGISTRATION

The Institutional Review Board at High Point University approved the study protocol. The clinical trial was registered at Clinicaltrials.gov (Identifier: NCT02754700) on 28/04/2016..

Bone-patellar tendon-bone, hamstring, and quadriceps tendon autografts for anterior cruciate ligament reconstruction in skeletally immature patients: a systematic review

INTRODUCTION

Historically, anterior cruciate ligament (ACL) ruptures in the paediatric age group were managed conservatively with bracing, casting, activity modification, and physical therapy. However, most of these patients had to reduce their sports activities, and secondary damages to the affected knee were prevalent.

SOURCE OF DATA

Published scientific literature in Embase, Web of Science, PubMed, and Google Scholar databases.

AREAS OF AGREEMENT

ACL reconstruction in children with open physes patients is debated. Any damage to the physes around the knee could lead to growth abnormalities and axial deviation of the knee.

AREAS OF CONTROVERSY

Different grafts are available and suitable for ACL reconstruction in skeletally immature patients; however, which graft performs better remains unclear.

GROWING POINTS

This systematic review compared bone-patellar tendon-bone (BPTB), hamstring tendon (HT), and quadriceps tendon (QT) autografts for ACL reconstruction in skeletally immature patients. The joint laxity, Patient-reported outcome measures (PROMs), return to sport, and complications were compared.

AREAS TIMELY FOR DEVELOPING RESEARCH

In skeletally immature patients, HT, BPTB, and QT autografts for ACL reconstruction yielded good outcomes. Comparative studies are strongly required to establish the most suitable autograft.

Anterior cruciate ligament injury prevention in sport: biomechanically informed approaches

This paper reviews a series of studies contributing to a framework for preventing anterior cruciate ligament (ACL) injuries in sport. As the majority of these injuries are non-contact in nature, theoretically, these injuries are preventable. The studies presented in this paper focus on understanding biomechanical countermeasures of ACL injury and how this knowledge can inform both screening and training intervention research and practice in sport. These countermeasures include: 1) modifying an athlete's technique to reduce externally applied loads to the knee; 2) increasing the muscle support around the knee and hip to counter elevated loads applied to the knee and; 3) improving an athlete's perception during dynamic sports tasks to increase planning time to coordinate desirable movement patterns. By furthering the empirical evidence of modifiable biomechanical countermeasures of ACL injury risk, we can better understand best practices for developing interventions on a mass scale to prevent ACL injuries in the sporting community.

Anterior Cruciate Ligament Injury Prevention Programs in Welsh Netball: A Survey of Knowledge, Implementation and Barriers Amongst Players and Coaches

Background Anterior cruciate ligament (ACL) injury prevention programs can reduce injury risk in various sports. The perception of ACL injury prevention programs amongst professional netball players and coaches has not been studied. Purpose The aim of this study was to determine (1) the level of awareness and experience of ACL injury prevention programs, (2) the use of ACL injury prevention programs, and (3) barriers and potential facilitators to implementing a sustainable ACL injury prevention program in netball. Materials and methods Female netball players representing Welsh senior and under-21 teams and elite and amateur coaches were invited electronically to participate in this web-based cross-sectional observational study between 1st May and 31st July 2021. Information on ACL injury susceptibility and seriousness, knowledge, experience, and implementation of ACL injury prevention programs were ascertained. Results Twenty-eight players (78%) and 29 coaches (13%) completed the questionnaire. Seventeen (61%) players and 15 (52%) coaches reported that female athletes were at greater risk of sustaining ACL injuries. Over 90% of respondents identified netball as high-risk, whilst 89% (n=25) of players and 76% (n=22) of coaches reported these injuries to be preventable. Only two (7%) players and six (21%) coaches utilised an ACL injury prevention program with a lack of time and engagement from coaches and players identified. The majority of respondents indicated that their club has neither promoted, advocated the use nor demonstrated exercises for ACL injury prevention. Over 90% of respondents would utilise an ACL injury prevention program if it minimised players' risk with appropriate information and demonstration of exercises. Conclusion This study highlights limited knowledge of female athletes' increased susceptibility to ACL injuries amongst players and coaches with a lack of communication and education on ACL injury prevention programs between sporting associations, coaches, and players. However, the results demonstrate willingness amongst both players and coaches to implement an ACL injury prevention program in netball.

The larger patellar tilt angle and lower intercondylar notch angle might increase posterior cruciate ligament injury risk: a retrospective comparative study

BACKGROUND

Posterior cruciate ligament (PCL) injuries are common ligament injuries of the knee, and previous studies often focused on the associations between the morphology of the knee and PCL injuries. Studies on the correlation between PCL injuries and patellofemoral alignment are limited.

METHODS

This retrospective study included 92 patients with PCL injured and 92 patients with PCL intact. Measurement parameters were compared between the two groups, including patellar tilt angle, congruence angle, patellar height, hip-knee-ankle angle, lateral trochlear inclination, femoral condyle ratio, bicondylar width, intercondylar notch width and index, notch angle, trochlear facet asymmetry, and trochlear sulcus depth and angle. Independent risk factors associated with PCL injuries were identified by logistic regression analyses.

RESULTS

In the PCL injured group, the patellar tilt angle was significantly larger (13.19 ± 5.90° vs. 10.02 ± 4.95°, P = 0.04); the intercondylar notch angle was significantly lower (60.97 ± 7.83° vs. 67.01 ± 6.00°, P = 0.004); the medial and lateral femoral condyle ratio were significantly larger (0.63 ± 0.64 vs. 0.60 ± 0.56, P = 0.031; 0.65 ± 0.60 vs. 0.58 ± 0.53, P = 0.005) than in the PCL intact group. There were 11 patients with patellar dislocation in the PCL injured group, accounting for 12%. In these patients, the patellar height was higher (1.39 ± 0.17 vs. 1.09 ± 0.25, P = 0.009); the trochlear sulcus angle was larger (157.70 ± 8.7° vs. 141.80 ± 8.78°, P < 0.001); and the trochlear sulcus depth was shallower (3.10 ± 1.20mm vs. 5.11 ± 1.48mm, P = 0.003) than those in the patients without patellar dislocation. Multivariate analyses showed that patellar tilt angle (each increase 1 degree, OR = 1.14) and intercondylar notch angle (each increase 1 degree, OR = 0.90) were independent risk factors for PCL injuries.

CONCLUSION

The patients with PCL injuries had larger patellar tilt angles, lower intercondylar notch angles, and longer posterior femoral condyles than patients with PCL intact. The larger patellar tilt angle and lower intercondylar notch angle might be risk factors for PCL injuries.

Parental Awareness and Attitudes Towards ACL Injury Prevention Programs in Youth Athletes

Background: The incidence of anterior cruciate ligament (ACL) injuries has steadily increased in young athletes and may have long-term implications for physical function and quality of life. ACL injury prevention programs have been developed and refined over the past several decades and have been shown to reduce the risk of ACL injuries by up to 70%. However, awareness and understanding of these programs among parents of athletes is unknown. This study aims to evaluate knowledge and attitudes toward ACL injury prevention programs for parents of young athletes involved in cutting and pivoting sports at varying levels of competition. Methods: A cross-sectional survey was nationally distributed to a convenience sample of parents of young athletes between the ages of 5 and 18. The survey focused on questions relating to demographic information, history of ACL injury, knowledge of ACL injury prevention programs, and factors influencing program awareness. Descriptive statistics were used to summarize participant characteristics and determine prevalence of program awareness. Results: A total of 244 parents completed the survey with 74% indicating their child's primary sport was soccer. Seventy-seven percent of these athletes began specializing in their primary sport at an average age of 8 years old (SD = 2.72). Only 18% of parents reported knowledge of ACL injury prevention programs and just 6% reported their child has ever participated in one. Of the 29 (12%) athletes who had experienced an ACL injury, only 17% had participated in an ACL injury prevention program. The most commonly reported barrier to ACL injury prevention program participation was the lack of awareness of where to get such training and it not being readily offered to their child. Sixty-eight percent of all parents would have their child participate in an ACL injury prevention program if offered to them. Conclusion: There is a lack of awareness of ACL injury prevention programs among parents of young athletes involved in high injury-risk sports. However, most parents would be interested in their child utilizing an ACL injury prevention program if it were offered. Levels of Evidence: Level IV Key Concepts•Given the young age at which athletes are specializing in their sport and other contributing factors, ACL injury prevention programs are becoming increasingly important.•Parents of youth athletes demonstrate a lack of awareness regarding ACL injury prevention programs.•Barriers to the utilization of ACL injury prevention programs include both a lack of knowledge of their availability and where to access this form of training.•Many parents are interested in having their child participate in an ACL injury prevention program.•Spreading awareness of ACL injury prevention programs will require a multi-faceted approach.

Organizational risk profiling and education associated with reduction in professional pitching arm injuries: a natural experiment

Background

Risk profiling and education are strategies implemented to help reduce injury risk; however, currently. there is little evidence on the effect of these interventions on injury incidence. The purpose of this study was to evaluate the influence of risk profiling and education on upper extremity injury incidence in minor league (MiLB) pitchers and to stratify by injury severity.

Methods

A prospective natural experiment study was conducted from 2013 to 2019 on MiLB pitchers. Beginning in the 2015 season, pitchers were examined and risk profiled for upper extremity injury. Shoulder external, internal, total range of motion, horizontal adduction, and humeral torsion were measured. Organizational risk profiling and education was implemented starting in 2015, based on preseason assessments. Chi-squared test was performed to investigate potential differences between shoulder range of motion risk categories between 2013-2014 (pre) and 2015-2019 (post) seasons. Interrupted time series analyses were performed to assess the association between organizational risk profiling and education on arm injury in MiLB pitchers and were repeated for 7-27 and 28+ day injury severity.

Results

297 pitchers were included (pre: 119, post: 178). Upper extremity injury incidence was 1.5 injuries per 1000 athletic exposures. Pitchers in the 2015-2019 seasons demonstrated increased preseason shoulder injury risk for internal (P = .003) and external (P = .007), while the 2013-2014 seasons demonstrated greater horizontal adduction risk (P = .04). There were no differences between seasons for total range of motion risk (P =.76). Risk profiling and education resulted in an adjusted time loss upper extremity injury reduction for the 2015-2019 seasons (0.68 (95% CI: 0.47, 0.99)), which impacted 7-27 days (0.62 (95% CI: 0.42, 0.93)) but not for 28+ days (0.71 (95% CI: 0.47, 1.06)) time loss. There was no reduction in combined trunk and lower extremity injuries for the 2015-2019 seasons (1.55 (95% CI: 0.79, 3.01)).

Conclusions

Organizational risk profiling and education appear to reduce professional pitching overall and 7-27-day upper extremity injury risk by 33%-38%. There was no difference in trunk and lower extremity injuries over the period, strengthening the reduction in upper extremity injury risk results. This suggests that while injury risk increased over time, organizational risk profiling mitigated the expected increase in upper extremity injury rates. Risk profiling and education can be used as a clinical screening and intervention tool to help decrease upper extremity injuries in professional baseball populations.

Female Collegiate Dancers' Physical Fitness across Their Four-Year Programs: A Prospective Analysis

Dance is physically demanding, requiring physical fitness (PF) that includes upper body, lower body, core fitness, and balance for successful performance. Whether PF changes as dancers advance from when they enter (freshmen) to when they graduate from their collegiate program (seniors) is unclear. We prospectively compared collegiate dancers' freshman-to-senior PF. We recorded PF in regard to upper body strength endurance (push-ups), core strength endurance (front, left-side, right-side, and extensor plank hold times), lower body power (single leg hop-SLH-distances % height; Leg Symmetry Index: LSI = higher/lower × 100, %), and balance (anterior reach balance, % leg length, LL; LSI balance = higher/lower × 100, %) in 23 female collegiate dancers (freshman age = 18.2 ± 0.6 years). Repeated measures ANOVAs (p ≤ 0.05) were used to compare measures from freshman to senior years. Across their collegiate programs, dancers' PF remained unchanged. Specifically, their upper body strength endurance push-up numbers (p = 0.93), their core strength endurance plank times (left: p = 0.44, right: p = 0.67, front: p = 0.60, p = 0.22), their SLH distances (left: p = 0.44, right: p = 0.85), and their symmetry (p = 0.16) stayed similar. Also, dancers' right leg (p = 0.08) and left leg balance (p = 0.06) remained similar, with better balance symmetry (p < 0.001) in seniors. Overall, dancers' PF did not change across their collegiate programs. Thus, female dancers' freshman PF may be an adequate baseline reference measure when devising rehabilitation programs and determining readiness-to-return-to-activity post injury.

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.

Morphological Risk Factors for Posterior Cruciate Ligament Tear and Tibial Avulsion Injuries of the Tibial Plateau and Femoral Condyle

BACKGROUND

Identification of morphological risk factors associated with the knee that threaten ligaments is important for understanding injury mechanisms and prevention. However, the morphological risk factors for posterior cruciate ligament (PCL) lesions are not clearly understood.

PURPOSE

To investigate whether the medial tibial depth (MTD), medial and lateral posterior tibial slope, asymmetry of the medial and lateral slopes, radius of the sagittal plane medial femoral condyle, coronal tibial slope, and notch width index (NWI) were risk factors for PCL intrasubstance tearing (PCLIT) and tibial avulsion fractures (PCLAF).

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Between January 2015 and March 2022, 82 patients with isolated PCLIT, 68 patients with isolated PCLAF, and 82 controls without any ligamentous or meniscal pathologic findings as determined via physical examination and magnetic resonance imaging were included. Values were compared among the 3 groups. Logistic regression analysis was performed to confirm the risk factors. Receiver operating characteristic curves were defined for the morphological indicators and combination of risk factors.

RESULTS

Logistic regression analysis revealed (1) MTD, lateral minus medial posterior tibial slope, radius of the posterior circle of the medial femoral condyle, and NWI as significant independent predictors for PCLIT and (2) MTD and NWI for PCLAF. The areas under the curve combining the 4 indicators for PCLIT and noncontact PCLIT were 0.79 (95% CI, 0.72-0.86) and 0.90 (95% CI, 0.85-0.96), respectively. The area under the curve for the combination of MTD and NWI for PCLAF was 0.78 (95% CI, 0.70-0.86).

CONCLUSION

Decreased MTD and NWI were associated with an increased incidence of PCLIT and PCLAF. Increased asymmetry of the medial and lateral slopes and the radius of the posterior circle of the medial femoral condyle were associated with the presence of PCLIT. In addition, the model of a combination of risk factors showed good predictive ability for noncontact PCLIT. These findings may aid clinicians in identifying patients at risk for PCL lesions. Further studies are warranted for identifying the effect of these factors on biomechanical mechanisms.

Intercondylar notch volume in patients with posterior cruciate ligament tears and tibial avulsion injuries: a study applying computed tomography

BACKGROUND

Two relatively common forms of injury exist in the posterior cruciate ligament (PCL) after the onset of trauma: PCL tear and tibial avulsion fracture. The mechanism for the occurrence of these different forms of injury is not known. Herein, we aimed to investigate this mechanism by comparing the intercondylar notch parameters between patients with PCL tears and those with PCL avulsion fractures of the tibial insertion.

METHODS

Fifty-three patients with PCL tears (37 male, 16 female: median age of 37 years: range 18-54 years) and 46 patients with avulsion fractures of tibial insertion (33 male, 13 female: median age of 33 years: range 18-55 years) were included in this study. Three-dimensional computed tomography (CT) was applied to measure the intercondylar notch width index and intercondylar notch volume. The intercondylar notch volume was simulated as the truncated-pyramid shape. Measurements of the top and bottom areas of this model were conducted on the slice containing the most proximal (S₁) and most distal (S₂) levels of Blumensaat's line. Femoral condyle height (h) was defined as the vertical distance between two parallel planes, and the volume was calculated as h(S₁ + S₂ + √(S₁S₂))/3. The values of S₁, S₂, h, notch volume, the body mass index (BMI), intercondylar notch width (NW), femoral condylar width (FW) and notch width index (NWI) were compared among the PCL tear and avulsion-fracture groups.

RESULTS

The results show a significant difference in the S₂ and normalized intercondylar notch volumes among patients with PCL tears and tibial avulsion injuries. Patients with PCL tears have smaller S₂ and intercondylar notch volumes than those with tibial avulsion. There were no significant differences between the two groups in S₁ or the 2D notch measurement parameters, such as the NW, FW and NWI. In addition, logistic regression analysis revealed notch volume and body mass index (BMI) as two significant independent predictors for PCL tears.

CONCLUSION

Decreased intercondylar notch volume and increased BMI are associated with an increased incidence of PCL tears. The occurrence of PCL tears and tibial avulsion injuries is influenced by the femoral intercondylar notch volume, and the measurement of the notch volume could be useful for identifying patients at risk for PCL tears.

An Anterior Cruciate Ligament (ACL) Injury Risk Screening and Reduction Program for High School Female Athletes: A Pilot Study

Background

Anterior cruciate ligament (ACL) injury causes physical, mental, and financial burdens. Therefore, it is imperative to screen, identify, and educate athletes who are at high-risk. The combination of screening and education could identify those at risk and potentially reduce future injuries.

Purpose

The purpose was to conduct a feasible community pre-season screening program for high school female athletes for the presence of known modifiable risk factors that predispose them to sustaining a non-contact ACL injury.

Study Design

Non-experimental prospective study.

Methods

A convenience sample of 15 healthy female athletes were recruited from local high schools, consisting of 11 soccer players and four basketball players.  A pre-season screening program was designed encompassing four stations that addressed modifiable neuromuscular and biomechanical risk factors including range of motion (ROM), jump-landing technique, strength, and balance. Athletes were categorized into high-risk versus low-risk groups based on cutoff scores previously established in the literature.

Results

Every athlete met the high-risk cutoff score for at least one extremity during the ROM screening, and some met high-risk cutoff scores for more than one ROM. Out of all four categories tested, lower extremity ROM demonstrated the greatest deficits.

Conclusion

This study identified athletes as having multiple modifiable risk factors that can be addressed with training and exercises. This supports implementing a pre-season program aimed at screening for injury risk factors.

Level of Evidence

Level 3.

Can MRI knee joint measurements predict the population at risk of ACL injury?

BACKGROUND

Anterior cruciate ligament (ACL) injuries have been increasing significantly over time. The relationship between the ACL injury and the knee joint structures is poorly understood. The purpose of this study is to examine whether the measurements of different structures in the knee joint are linked with ACL injury in affected patients.

METHODS

This retrospective case-control study included patients who suffered from ACL tears and underwent magnetic resonance imaging (MRI). A control group of patients with no knee pathologies on MRI was included. Fourteen knee variables, including lateral meniscus (LM) posterior horn height, length, depth, and volume; medial meniscus (MM) posterior horn height, length, depth, and volume; lateral and medial (MFC) femoral condyle sphere diameter; lateral and medial tibial plateau length; and patella tendon horizontal and vertical diameter, were collected. A multivariate logistic regression including LM posterior horn depth, MM posterior horn length, MM volume, MFC sphere diameter, and patella tendon horizontal diameter and receiver operating characteristic curve, was used to compare the two groups.

RESULTS

A total of 85 patients were included in our study; 54 suffered from ACL injuries and 31 as a control group with normal knee MRI. Logistic regression revealed that increased LM posterior horn depth (OR = 1.27; 95% CI = 1.03-1.56; p = 0.028), decreased MM posterior horn length (OR = 0.71; 95% CI = 0.55-0.93; p = 0.013), and MFC sphere diameter (OR = 1.20; 95% CI = 1.01-1.43; p = 0.035) were independent risk factors for ACL rupture. The MFC sphere diameter yielded the highest area under the curve: 0.747 (95% CI, 0.632-0.862). No difference was found in the other measurements between the two groups.

CONCLUSIONS

Concerning the difference in anatomical variations, the lateral meniscus posterior horn depth and medial femoral condyle sphere diameter were higher, while medial meniscus posterior horn length was lower in patients with an ACL injury. These structural knee measurements could have a possible increase in the likelihood of sustaining an ACL injury and can be used by clinicians to predict ACL injury.

Prevention of Non-Contact Anterior Cruciate Ligament Injuries among Youth Female Athletes: An Umbrella Review

Anterior cruciate ligament (ACL) injuries account for a large percentage of knee injuries, disproportionately affecting female athletes. To help health professionals stay current, we performed an umbrella review to evaluate the effectiveness of ACL injury prevention programs in reducing non-contact ACL injury rates, determine the effective components within interventions, and provide clinical recommendations. Twelve databases (Medline, Embase, Cochrane Database of Systematic Reviews, SPORTDiscus, Cumulative Index to Nursing and Allied Health Literature, PEDro, Web of Science Core Collection, Epistemonikos, TRIP, BC Guidelines and Protocols, CPG Infobase, ProQuest Dissertations and Theses Global) were searched in May 2021 to identify relevant systematic reviews and meta-analyses. Four databases were searched again in September 2021 to identify recent primary literature. Non-contact ACL injury data were extracted to calculate incidence rate ratios (IRRs) and these were combined using an inverse variance random-effects model. A qualitative assessment of included reviews was performed. The methodological quality of the studies was assessed using a Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) or Cochrane Risk-of-Bias Tool for Randomized Trials (RoB 2). Sixteen reviews and two primary studies met the inclusion criteria. Across 11 primary studies, prevention programs were effective in reducing non-contact ACL injuries by 64% (IRR = 0.36 (95% CI: 0.18-0.70)). A multi-faceted exercise program, beginning in the pre-season and containing at least three exercise types, may be beneficial in reducing ACL injury risk.

Trends in Australian knee injury rates: An epidemiological analysis of 228,344 knee injuries over 20 years

BACKGROUND

Acute knee injuries are a key predisposing risk factor for knee osteoarthritis. Public health interventions require in-depth epidemiological evidence to determine which knee injuries are problematic in critical age and sex demographics.

METHODS

Descriptive epidemiological analysis of longitudinal data on knee injuries (July 1998 - June 2018) from the National Hospital Morbidity Database in Australia were studied. The main outcomes where the population-related knee injury frequency, incidence per 100,000 and annual growth rate (%) over the 20-year observation period. Age-group and sex differences were also studied to determine demographic-specific trends.

FINDINGS

228,344 knee injuries were diagnosed over the 20-year analysis period. Significantly rising annual incidences were observed for total knee injuries, anterior cruciate ligament (ACL) injuries and knee contusions in males and females. Posterior cruciate ligament (PCL) injuries and knee dislocations were also rising in females, but not males. Greater annual growth rates were observed for females compared to males for total knee injuries, knee contusions, PCL injuries and knee dislocations. Demographic analysis revealed that the highest annual growth rate in injury incidence (10.4%) was observed for ACL injuries in females aged 5-14 years old.

INTERPRETATION

Increasing annual incidence of knee injuries was observed over the 20-year period. Males have a higher incidence of knee injury per capita than females, but the gap appears to have narrowed over the 20-year analysis period. Younger Australians show a precipitous rise in the annual number of ACL injuries, particularly for females aged 5-14 years. These trends warrant urgent intervention.

FUNDING

None.

Association of COL5A1 gene polymorphisms and musculoskeletal soft tissue injuries: a meta-analysis based on 21 observational studies

Objective

Inconsistent findings existed on the correlation of collagen type V α1 (COL5A1) gene polymorphisms and musculoskeletal soft tissue injuries (MSTIs). The purpose of this study was to collect and combine the current evidences by a meta-analysis approach.

Methods

Six online databases were searched up to August, 2021. The methodological quality of each individual study was evaluated based upon Newcastle–Ottawa Scale (NOS). The strength of the effect size was presented by odds ratio (OR) with 95% confidence interval (95%CI) in five genetic models. The data were analyzed using Review Manager 5.3.

Results

Twenty-one studies were eligible to this meta-analysis. The study quality was deemed fair to excellent according to NOS. In the overall analyses, the merged data suggested that rs12722, rs71746744, and rs3196378 polymorphisms were correlated to an increased susceptibility to MSTIs. But the association was not established in rs13946 or rs11103544 polymorphism. For rs12722 polymorphism, stratified analyses by injury type and ethnicity identified the association mainly existed in ligament injury and among Caucasian population. For rs13946 polymorphism, subgroup analysis suggested the association existed in tendon and ligament injuries.

Conclusion

This study supports that rs12722 is associated with an elevated susceptibility to ligament injury, especially in the Caucasian population. Rs13946 polymorphism appears to increase the risk to tendon and ligament injuries. Rs71746744 and rs3196378 polymorphisms have a tendency to confer an elevated risk to MSTIs. However, no relevance is found between rs11103544 polymorphism and MSTIs.

Vancomycin Soaking Is Highly Cost-Effective in Primary ACLR Infection Prevention: A Cost-Effectiveness Study

BACKGROUND

Although presoaking grafts in vancomycin has been demonstrated to be effective in observational studies for anterior cruciate ligament reconstruction (ACLR) infection prevention, the economic benefit of the technique is uncertain.

PURPOSE

To 1) determine the cost-effectiveness of vancomycin presoaking during primary ACLR to prevent postoperative joint infections and 2) to establish the break-even cost-effectiveness threshold of the technique and determine its cost-effectiveness across various international health care settings.

STUDY DESIGN

Economic and decision analysis; Level of evidence, 2.

METHODS

A Markov model was used to determine cost-effectiveness and the incremental cost-effectiveness ratio of additional vancomycin presoaking compared with intravenous antibiotic prophylaxis alone. A repeated search of the PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials databases, using the same criteria as a recent meta-analysis, was completed. A repeated meta-analysis of 9 cohort studies (level 3 evidence) was completed to determine the odds ratio of infection with vancomycin presoaking compared with intravenous antibiotics alone. Estimated costs of the vancomycin technique, treatment of infection, and further surgery were sourced from local hospitals and literature. Transitional probabilities for further surgery, including revision reconstruction and primary arthroplasty, were obtained from the literature. Probabilistic sensitivity analyses and a 1-way sensitivity analysis were performed to evaluate the ACLR infection rate break-even threshold for which the vancomycin technique would be no longer cost-effective.

RESULTS

The vancomycin soaking technique provides expected cost savings of $660 (USA), A$581 (Australia), and €226 (Spain) per patient. There was an improvement in the quality-adjusted life-years of 0.007 compared with intravenous antibiotic prophylaxis alone (4.297 vs 4.290). If the infection rate is below 0.014% with intravenous antibiotics alone, the vancomycin wrap would no longer be cost-effective.

CONCLUSION

The vancomycin presoaking technique is a highly cost-effective method to prevent postoperative septic arthritis after primary ACLR.

Increased lateral femoral condyle ratio measured by MRI is associated with higher risk of noncontact anterior cruciate ligament injury

BACKGROUND

Studies have shown a significant association between the radiographically measured lateral femoral condyle ratio (LFCR) and anterior cruciate ligament (ACL) injury. However, it is unclear whether LFCR measured by magnetic resonance imaging (MRI) is associated with a higher risk of noncontact ACL injury.

OBJECTIVE

To investigate the effect of LFCR on the risk of noncontact ACL injury by MRI. 2 to investigate the association of LFCR measured by MRI with multiple bone morphological risk factors and evaluate the most sensitive risk predictors of noncontact ACL injury.

METHODS

A total of 116 patients, including 58 subjects with noncontact ACL injury and 58 age-matched and sex-matched controls with only meniscus injury, were included in this retrospective case-control study. LFCR, lateral tibial slope (LTS), lateral tibial height (LTH), medial tibial slope (MTS), and medial tibial depth (MTD) were measured on MRI. The differences in each index between the two groups were compared, and risk factors were screened by single-factor logistic regression analysis. Indicators with P values < 0.1 were included in the logistic regression equation. The critical values and areas under the curve (AUCs) of independent risk factors were determined by receiver operating characteristic (ROC) curve analysis. Finally, the diagnostic performance of each risk factor was evaluated by the Z-test.

RESULTS

A total of 116 patients who met the inclusion criteria were included in the final analysis (58 cases in the noncontact ACL injury group and 58 cases in the control group). Patients with noncontact ACL injury had a higher femoral LFCR (0.64 ± 0.03) than patients with isolated meniscus tears. Among all the risk factors for ACL injury, the AUC for LFCR was the largest, at 0.81 (95% CI, 0.73-0.88), and when the critical value was 0.61, the sensitivity and specificity for the diagnosis of ACL injury were 0.79 and 0.67, respectively. When combined with LTH (> 2.35 mm), the diagnostic performance was improved. The AUC was 0.85 (95% CI, 0.78-0.92), the sensitivity was 0.83, and the specificity was 0.76.

CONCLUSION

This study shows that an increased LFCR is related to an increased risk of noncontact ACL injury as determined by MRI. LFCR and LTH are sensitive risk factors for noncontact ACL injury and may help clinicians identify individuals prone to ACL injury, allowing prevention and intervention measures to be applied.

Epidemiology of Pediatric Basketball Injuries Presenting to Emergency Departments: Sex- and Age-Based Patterns

Background:

There is limited epidemiologic data on pediatric basketball injuries and the comparison of these injuries before and after adolescence and between male and female athletes.

Purpose:

To assess common sex- and age-based injury patterns in pediatric basketball players.

Study Design:

Descriptive epidemiology study.

Methods:

Injury data from the National Electronic Injury Surveillance System (NEISS) and participation data from the National Sporting Goods Association were used to complete this study. Data on pediatric basketball injuries between January 2012 and December 2018 in patients aged 7 to 11 years (childhood) and 12 to 17 years (adolescence) were extracted and used to calculate national injury incidence rates with 95% CIs. Sex and age group patterns were examined utilizing Pearson chi-square tests. Z tests were conducted for the comparison of injury rates between female and male athletes in each age group and overall injury rate across age groups.

Results:

An average of 9582 basketball injuries were reported annually in the NEISS, which calculated to an annual national estimate of 294,920 injuries. The most common diagnoses were ankle strain/sprain (17.7%), finger strain/sprain/fracture (12.1%), concussion/head injury (9.4%), knee strain/sprain (4.5%), and facial laceration (3.3%). There was a significant increase in injury prevalence in adolescents (12- to 17-year-old category: 238,678 injuries per year) when compared with childhood (7- to 11-year-old category: 56,242 injuries per year) (P < .0001). Concussions/head injuries occurred at a high rate in childhood, second only to finger strain/sprain/fracture, and at a similar rate in females and males (injuries per 100,000 athlete-days: 4.9 [95% CI, 3.1-6.7] vs. 5.9 [4.3-7.5], respectively; P = .41). From childhood to adolescence, injury prevalence increased for all areas and across both sexes, except for female finger strain/sprain/fracture; however, the rate of increase for concussion/head injuries and knee injuries was significantly higher in female compared with male athletes (P < .0001 for both). In adolescents, ankle injuries were the most common injury overall.

Conclusion:

Ankle injuries continue to be the most predominant pediatric basketball injury. However, disproportionate rates of both knee and concussion/head injuries in female athletes during adolescent basketball are of concern and have implications for injury prevention.

ACL injury prevention: Where have we come from and where are we going?

Anterior cruciate ligament (ACL) injuries are one of the most common and severe knee injuries across sports. As such, ACL injury prevention has been a focus of research and sports medicine practice for the past three-plus decades. Examining the current research and identifying both clinical strategies and research gaps, the aim of this review is to empower clinicians and researchers with knowledge of where the ACL injury prevention literature is currently and where it is going in the future. This paper examines the mechanism of ACL injury prevention, screening, implementation, compliance, adherence, coronavirus, and areas of future research. Clinical significance: The time lag between research and practical implementation in general healthcare settings can be as long as 17 years; however, athletes playing sports today are unable to wait that long. With effective programs already established, implementation and adherence to these programs is essential. Strategies such as coaching education, increasing awareness of free programs, identifying barriers, and overcoming implementation obstacles through creative collaboration are just a few ways that could help improve both ACL injury prevention implementation and adherence.

Changes in U.S. girls' participation in high school sports: implications for injury awareness

CONTEXT

The number of female athletes has grown exponentially since Title IX. However, little data exists on the proportion of women and girls who play each sport.

OBJECTIVE

To quantify changes in female sports participation in high school sports from 1973 to 2018.

DESIGN

Retrospective analysis of data from the National Federation of State High School Associations Participation Survey.

SETTING

US high schools.

PARTICIPANTS

US high school athletes from 1973 to 2018.

MAIN OUTCOME MEASURES

Percentage of female participation for each high school sport in 5-year intervals; and changes in rates of participation by player gender and sport at designated intervals.

RESULTS

From 1973 to 2018, the percentage of high school sports played by girls increased from 24.2% to 42.9% ([95%CI, 18.6,18.8], p < 0.0001). In the 14 sports included in our study, all had an increase in the percentage of female participation between 1973 and 2018. >80% of the increases occurred between 1973 and 1998 for all sports except lacrosse, ice hockey, football, and wrestling. Between 1998 and 2018, the percentage of girls playing each sport increased by less than 5% in all sports, except for ice hockey (11.5%, 95% CI 11.0, 12.0, p < 0.001) and wrestling (7.1%, 95% CI 6.9, 7.1, p < 0.001).

CONCLUSIONS

Girls' participation in high school sports continues to grow not only in numbers but in the types of sports played. Between 1998 and 2018, the greatest increases were noted in ice hockey and wrestling, which had fewer than 1% female participation before 1998. Physicians providing care for female athletes should be aware of these changes and understand the potential injuries associated with these sports.

Does prevention pay off? Economic aspects of sports injury prevention: a systematic review

OBJECTIVE

To identify, summarise and critically assess economic evaluation studies on sports injury prevention strategies.

DESIGN

Systematic review.

DATA SOURCES

PubMed, SportDiscuss.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

The current literature was searched following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Economic analyses published since 2010 were checked for inclusion. The methodological quality of the studies was assessed using the Oxford Level of Evidence for economic and decision analysis; underlying randomised controlled trials (RCTs) were rated according to the Physiotherapy Evidence Database (PEDro) Scale, and risk of bias was assessed using the Revised Cochrane risk-of-bias tool.

RESULTS

Ten studies fulfilled the inclusion criteria. The quality assessment revealed limited data quality. For trial-based analysis, underlying RCTs were of good quality and had a low risk of bias. Prevention concepts for general injury reduction showed effectiveness and cost savings. Regarding specific injury types, the analysis of the studies showed that the best data are available for ankle, hamstring and anterior cruciate ligament injuries. Measures using specific training interventions were the predominant form of prevention concepts; studies investigating these concepts showed cost-effectiveness with total cost savings between €24.82 and €462 per athlete.

CONCLUSION

Injury prevention strategies that were studied are cost-effective. However, estimates and outcomes vary throughout the included studies, and precluded pooling of existing data. Knowledge about the cost-effectiveness of evaluated prevention measures will help improve the acceptance and application of prevention initiatives.

Safety and Effectiveness of a Perturbation-based Neuromuscular Training Program on Dynamic Balance in Adolescent Females: A Randomized Controlled Trial

BACKGROUND

Adolescent females are at much greater risk for ACL injury than their male counterparts when participating in the same sports. Preventative and pre-operative rehabilitation neuromuscular (NM) exercise programs are often recommended to improve knee function and reduce injury rates. The effectiveness of perturbation-based NM training program has been established in an adult population but has yet to be investigated in the at-risk adolescent female population.

PURPOSE

To determine the effectiveness of a perturbation-based NM exercise program in a group of physically active adolescent females.

STUDY DESIGN

Prospective randomized trial.

METHODS

Twenty-four healthy and an exploratory group of 10 ACL-injured females (ages 12-18) were equally randomized into a perturbation-based NM training or control group and evaluated before and after a five-week intervention period. The primary outcome of dynamic balance was measured using the Y-Balance test (YBT); secondary outcome measures included lower limb strength, proprioception, and flexibility.

RESULTS

The perturbation-based NM training intervention was safely completed by all participants but had no significant effect on YBT scoring, lower limb strength, proprioception or flexibility in either the healthy or ACL-injured groups.

CONCLUSIONS

Perturbation-based NM training is safe, but may offer little preventative benefit for healthy or pre-operative rehabilitation benefit for ACL-injured adolescent females. Future research should examine whether the effectiveness of perturbation-based NM training is influenced by the length of the training intervention, training intensity, or when it is combined with other forms of prophylactic or pre-surgical rehabilitation frequently used with at-risk adolescent females who regularly participate in sport.

LEVEL OF EVIDENCE

Level 3.

The Reliability of Common Functional Performance Tests within an Experimental Test Battery for the Lower Extremities

The main aim of this study was to determine the test-retest reliability of an experimental functional test battery: Y-balance test (YBT), single-leg countermovement jump (SLCMJ), single-leg hop for distance (SLH), side-hop (SH), speedy-jump (SJ), agility-T (AT), and lower extremity functional test (LEFT). Secondary aims were (1) to determine the mean range for the limb symmetry index (LSI) and (2) to detect significant differences in performance between test-retest sessions. Twenty-two healthy adults (14 males, 8 females; age 23.3 ± 3.9) were tested by the same rater during two different sessions (T1-T2), with a seven-day interval, under the same conditions. Reliability analysis showed good-to-excellent reliability (0.89 < ICC < 0.97; 0.80 < α < 0.98) for the test battery. LSI ranged from 95.9 ± 6.7% (SH-T1) to 104.4 ± 12.5% (SLCMJ-T2). Repeated measures ANOVA detected significant performance differences between sessions in the LEFT (p = 0.009) and for non-dominant sides in the SLH (p = 0.015), SH (p = 0.007), and SJ (p = 0.011). The high reliability of the test battery suggests a potential use in clinical sports practice. The LSI range of ≥95% was proposed as a benchmark for healthy adults. Learning effect seems to have played a crucial role in the T2 improvements of the non-dominant side for hop performances (SLH, SH, SJ) and speed performance (LEFT).

Predictors of Pediatric Anterior Cruciate Ligament Injury: The Influence of Steep Lateral Posterior Tibial Slope and Its Relationship to the Lateral Meniscus

PURPOSE

To examine the relationship between posterior tibial slope and lateral meniscal bone angle (LMBA) on anterior cruciate ligament (ACL) tear risk in a pediatric population.

METHODS

In this case-control study, non-contact ACL-injured pediatric patients with no significant lateral meniscal lesions were matched by age and sex in a 1:1 ratio to a group of radiologically normal controls. Knee magnetic resonance imaging (MRI) studies were analyzed by 3 independent, blinded observers measuring the medial posterior tibial slope (MTS), lateral posterior tibial slope (LTS), and LMBA. Sagittal slope asymmetry was calculated as the absolute difference in degrees between slopes, and the relationship between LMBA and LTS was calculated as a ratio. Binary logistic regressions identified independent predictors of ACL injury. Receiver operator characteristics were performed to determine predictive accuracy.

RESULTS

20 study patients were compared with 20 sex- and age-matched controls (age 14.8 ± 2.42, mean ± standard deviation). LTS was significantly higher in the ACL-injured group (11.30° ± 3.52° versus 7.00° ± 2.63°, P = .0001), as were the absolute slope difference (7.10 ± 2.92° versus 3.14 ± 3.25°, P = .0002) and LTS:LMBA ratio (0.46 ± 0.17 versus 0.26 ± 0.12, P = .0001). No significant differences were observed for MTS or LMBA. Independent predictors were LTS (odds ratio [OR] 1.58, 95% confidence interval [CI] 1.18 to 2.13, P = .002), LTS:LMBA ratio (OR 3.13, 95% CI 1.48 to 6.62, P = .003), and absolute slope difference (OR 1.65, 95% CI 1.17 to 2.32, P = .005). LTS:LMBA ratio was the strongest predictor variable (area under the curve 0.86).

CONCLUSION

This study suggests that LTS, absolute slope difference, and LTS:LMBA ratio are significant pediatric ACL-injury risk factors. All 3 demonstrate good predictive accuracy; however, the relationship between steep LTS and shallow LMBA was the strongest predictor.

LEVEL OF EVIDENCE

III, case-control study.

Secondary Injuries After Pediatric Anterior Cruciate Ligament Reconstruction: A Systematic Review With Quantitative Analysis

BACKGROUND

In the skeletally mature anterior cruciate ligament (ACL) reconstruction population, patients aged <25 years are at significantly increased risk of graft failure and injury to the contralateral ACL. Skeletal immaturity often affects graft selection and reconstruction technique.

PURPOSE

To examine the incidence of ipsilateral graft failure and contralateral ACL injury in the skeletally immature patient population.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

Using the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines, we reviewed all literature that involved ACL reconstruction performed on skeletally immature patients between May 1976 and May 2019. Patient demographics, surgical technique, and the prevalence of ipsilateral graft failure or subsequent contralateral ACL injury were recorded. Ipsilateral, contralateral, and secondary ACL injuries were then compared between sexes via chi-square tests.

RESULTS

A total of 24 articles (1254 children; 1258 knees) met inclusion criteria for analysis. Ipsilateral graft failures occurred in 105 of 1258 patients (8.3%), and there were no statistically significant sex differences in the prevalence of graft failures (female, 9.7%; male patients, 7.1%; P = .14). The prevalence of contralateral ACL injury was significantly greater in female (29/129; 22.5%) than male (18/206; 8.7%; P = .0004) patients in the 9 studies that reported contralateral injury. Skeletally immature female patients were at significantly increased risk of contralateral ACL injury (odds ratio = 3.0; P = .0006) when compared with their male counterparts.

CONCLUSION

In the literature to date, 1 in 3 female skeletally immature patients experienced an ipsilateral graft failure or contralateral ACL injury. Regardless of sex, the 24% prevalence of secondary injury after pediatric ACL reconstruction is almost identical to previously published secondary injury rates in skeletally mature patients <25 years old. As such, skeletal maturity alone does not seem to be a determinant of secondary injury; however, there is a clear need to improve postoperative rehabilitation, activity progression, and return-to-play testing to allow a safe return to sports that protects the long-term health of the reconstructed and contralateral limbs, especially for female patients.

Estimates of Direct and Indirect Costs of Ankle Fractures: A Prospective Analysis

BACKGROUND

The quantification of the costs of ankle fractures and their associated treatments has garnered increased attention in orthopaedics through cost-effectiveness analysis. The purpose of this study was to prospectively assess the direct and indirect costs of ankle fractures in operatively and nonoperatively treated patients.

METHODS

A prospective, observational, single-center study was performed. Adult patients presenting for an initial consult for an ankle fracture were enrolled and were followed until recurring indirect costs amounted to zero. Patients completed a cost form at every visit that assessed time away from work and the money spent in the last week on transportation, household chores, and self-care due to an ankle fracture. Direct cost data were obtained directly from the hospital billing department.

RESULTS

Sixty patients were included in this study. With regard to patient characteristics, the mean patient age was 46.5 years, 55% of patients were female, 10% of patients had diabetes, and 17% of patients were active smokers. Weber A fractures composed 12% of fractures, Weber B fractures composed 72% of fractures, and Weber C fractures composed 18% of fractures. Operatively treated patients (n = 37) had significantly higher total costs and direct costs compared with nonoperatively treated patients (p < 0.01). In all patients, losses from missed work accounted for the largest portion of total and indirect costs, with a mean percentage of 35.8% of the total cost. The mean period preceding return to work of the 39 employed patients was 11.2 weeks. Longer periods of return to work were significantly associated with surgical fixation and having less than a college-level education (p < 0.05). The mean time for recurring observed costs to cease was 19.1 weeks.

CONCLUSIONS

In patients treated operatively and nonoperatively, the largest discrete cost component was a specific indirect cost. Indirect costs accounted for a mean of 41.3% of the total cost. Although the majority of the direct costs of ankle fractures are accrued in the period immediately following the injury, indirect cost components will regularly be incurred for nearly 5 months and often longer. To capture the full economic impact of these injuries, future research should include detailed reporting on an intervention's impact on the indirect costs of ankle fractures.

LEVEL OF EVIDENCE

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

Systematic review of unintentional injury prevention economic evaluations 2010-2019 and comparison to 1998-2009

BACKGROUND

Health economic evaluation studies (e.g., cost-effectiveness analysis) can provide insight into which injury prevention interventions maximize available resources to improve health outcomes. A previous systematic review summarized 48 unintentional injury prevention economic evaluations published during 1998-2009, providing a valuable overview of that evidence for researchers and decisionmakers. The aim of this study was to summarize the content and quality of recent (2010-2019) economic evaluations of unintentional injury prevention interventions and compare to the previous publication period (1998-2009).

METHODS

Peer-reviewed English-language journal articles describing public health unintentional injury prevention economic evaluations published January 1, 2010 to December 31, 2019 were identified using index terms in multiple databases. Injury causes, interventions, study methods, and results were summarized. Reporting on key methods elements (e.g., economic perspective, time horizon, discounting, currency year, etc.) was assessed. Reporting quality was compared between the recent and previous publication periods.

RESULTS

Sixty-eight recent economic evaluation studies were assessed. Consistent with the systematic review on this topic for the previous publication period, falls and motor vehicle traffic injury prevention were the most common study subjects. Just half of studies from the recent publication period reported all key methods elements, although this represents an improvement compared to the previous publication period (25 %).

CONCLUSION

Most economic evaluations of unintentional injury prevention interventions address just two injury causes. Better adherence to health economic evaluation reporting standards may enhance comparability across studies and increase the likelihood that this type of evidence is included in decision-making related to unintentional injury prevention.

Effect of Sex on Anterior Cruciate Ligament Injury-Related Biomechanics During the Cutting Maneuver in Preadolescent Athletes

Background:

There are 2 movement patterns associated with an anterior cruciate ligament (ACL) injury: dynamic valgus and stiff landing. Although sex-dependent differences have been identified for adults, less is known for preadolescent athletes regarding movement patterns known to load the ACL.

Hypothesis:

We hypothesized that girls would demonstrate greater vertical ground reaction forces and knee valgus angles. We further hypothesized that the exercise intervention would affect girls more than boys and that this would primarily be demonstrated in less sagittal plane excursions, increased vertical ground reaction forces and knee valgus moments for girls than for boys.

Study Design:

Controlled laboratory study.

Methods:

Male and female soccer and handball players (n = 288; age range, 9-12 years) were recruited. A motion capture system synchronized to a force platform was used to record 5 trials of a cutting maneuver before and after a 5-minute fatigue intervention. Linear mixed models were constructed, and analysis of variance was used to analyze differences in outcomes associated with the sex of the athletes.

Results:

Boys showed greater peak knee valgus moment (0.26 vs 0.22 N·m/kg, respectively; P = .048), peak knee internal rotation moment (–0.13 vs –0.10 N·m/kg, respectively; P = .021), knee rotation excursion (–7.9° vs –6.9°, respectively; P = .014), and knee extension excursion (2.7° vs 1.4°, respectively; P < .001) compared with that in girls. A significant sex × fatigue intervention interaction (F = 7.6; P = .006) was found, which was caused by a greater increase in first peak vertical ground-reaction force (vGRF) from before to after the fatigue intervention for girls (15.3 to 16.0 N/kg) compared with boys (16.4 to 16.5 N/kg).

Conclusion:

Differences detected for biomechanical factors during the cutting maneuver do not point to a greater ACL injury risk for prepubescent or early pubescent girls than for boys. Nonetheless, girls go on to develop more detrimental movement patterns in adolescence than those in boys in terms of biomechanical risk factors.

Clinical Relevance:

Early adolescence is a good target age to learn and develop muscular control; balance, strength; flexibility; and jumping, running, and landing control. This time of physical and athletic growth may therefore be an appropriate period to influence biomechanical factors and thereby task execution and the injury risk.

An In-Depth Analysis of Graft Rupture and Contralateral Anterior Cruciate Ligament Rupture Rates After Pediatric Anterior Cruciate Ligament Reconstruction

BACKGROUND

Reported rates of graft rupture and contralateral anterior cruciate ligament (ACL) rupture after ACL reconstruction (ACLR) are higher among pediatric patients than adults. Previous series may have underestimated postoperative event risk because of small sample sizes and high proportions of dropouts.

PURPOSE

To calculate rates of graft rupture and contralateral ACL rupture after ACLR in a large pediatric series.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

ACLRs performed in our tertiary care children's hospital system over a period of >7 years were identified through billing review. Cases were sorted based on operative technique, with all-epiphyseal ACLRs considered separately. Transphyseal ACLRs were divided into 2 groups based on patient age, with a cutoff of 16 years. Clinic follow-up data as well as prospectively collected survey data were used to note graft rupture and contralateral ACL rupture events. Rates of graft rupture and contralateral ACL rupture were calculated using Kaplan-Meier survival analysis.

RESULTS

The final data set included 996 patients. A total of 161 patients underwent all-epiphyseal ACLR. Of the remaining transphyseal surgeries, 504 patients were <16 years of age at the time of surgery and 331 were ≥16 years. The 4-year cumulative rate of graft rupture via Kaplan-Meier survival analysis was 19.7% among all patients. The rate was 18.2% among all-epiphyseal ACLRs, 21.6% among transphyseal ACLRs in patients <16 years, and 16.4% among transphyseal ACLRs in patients ≥16 years (P = .855). Survival analysis estimated the 4-year cumulative rate of contralateral ACL rupture at 12.0% among all patients: 6.63% among all-epiphyseal ACLRs, 15.7% among transphyseal ACLRs in patients <16 years, and 8.05% among transphyseal ACLRs in patients ≥16 years (P = .093).

CONCLUSION

This is the largest series of pediatric ACLRs yet reported, and it shows that the risks of another ACL injury after first-time ACLR are higher than previously reported. The risk of contralateral ACL rupture was lower than that for graft rupture. Our methods, including prospective follow-up surveys and survival analysis to generate cumulative rate estimates, provide a best-practice example for future case series calculations. Our results provide insight into the postoperative course of pediatric patients undergoing ACLR and are crucial for preoperative patient and family counseling. Understanding these risks may also influence return-to-play decisions.

Canine cruciate ligament ruptures: Implications for financial costs and human health

The cranial cruciate ligament (CCL) in dogs is homologous to the anterior cruciate ligament (ACL) in humans. Factors that place an individual at-risk for noncontact ruptures are not clearly defined in humans or dogs. Cyclic variation in human females as well as early spay/neuter in canines has frequently implicated hormonal variation, however these factors do not fully explain the human dimorphic or canine breed rupture rates. The present study examined dogs as a proxy model for humans to better understand the covariance. A random clinical data sample from the Oklahoma State University Veterinary Hospital was obtained on (n = 29) CCL surgical cases and nonsurgical (n = 28) controls. A statistical test for association of spay/neuter with CCL rupture was significant (chi-square = 21.7, p < .01). Sex balance between the groups was not significantly (p > .01) different. Data on other variables related to morphometric variability such as the tibial plateau angle was not available on the nonsurgical sample and comparisons could only be made to values from the literature. Though there may have been sample bias, this preliminary study found that more large than small dogs were represented in the surgical sample. Our results also support the claim that spayed/neutered dogs are more likely to rupture their CCL than intact dogs. Given the high costs of surgical repair, both for canines and humans, we argue for multivariate studies that investigate the interaction of variables in a larger subject sample which can provide comparable data on all parameters.

Hip biomechanics differ in responders and non-responders to an ACL injury prevention program

PURPOSE

To investigate the differences in demographic, anthropometric, biomechanical, and/or performance variables between those that do (responders) and do not (non-responders) exhibit reductions in knee abduction moments after an anterior cruciate ligament injury prevention program (ACL-IPP).

METHODS

Forty-three adolescent female athletes completed biomechanical (3D motion analysis of a drop vertical jump) and performance testing before and after randomization into a 6-week ACL-IPP. Participants were classified into responders and non-responders based on their level of reduction of knee abduction moment from pre- to post-test.

RESULTS

Compared to non-responders, responders exhibited increased hip adduction excursion at baseline (p = 0.02) and trended towards attending more training sessions (p = 0.07) and participating in soccer and not basketball (p = 0.07). Responders also showed greater improvements in hip flexion angles (p = 0.02) and moments (p < 0.001), and knee abduction angles (p < 0.001) and excursions (p = 0.001). There were no significant differences in age or experience with prior injury prevention programs (n.s.).

CONCLUSIONS

After an ACL-IPP, athletes that exhibit the greatest reduction in knee abduction moments exhibit greater hip adduction excursion at baseline and show corresponding improvements in hip flexion and knee abduction kinematics and hip flexion moments. These results can help clinicians prospectively identify individuals that may not respond to an ACL-IPP and target individualized training for those at risk of injury.

LEVEL OF EVIDENCE

I.

CLINICAL TRIAL REGISTRATION NUMBER

Clinicaltrials.gov NCT02530333.

Safer and Cheaper: An Enhanced Milestone-Based Return to Play Program After Anterior Cruciate Ligament Reconstruction in Young Athletes Is Cost-Effective Compared With Standard Time-Based Return to Play Criteria

BACKGROUND

Safe return to play (RTP) after anterior cruciate ligament (ACL) reconstruction is critical to patient satisfaction. Enhanced rehabilitation after ACL reconstruction with appropriate objective criteria for RTP may reduce the risk of subsequent injury. The cost-effectiveness of an enhanced RTP (eRTP) strategy relative to standard post-ACL reconstruction rehabilitation has not been investigated.

PURPOSE

To determine if an eRTP strategy after ACL reconstruction is cost-effective compared with standard rehabilitation.

STUDY DESIGN

Economic and decision analysis.

METHODS

A decision-analysis model was utilized to compare standard rehabilitation with an eRTP strategy, which includes additional neuromuscular retraining, advanced testing, and follow-up physician visits. Cost-effectiveness was evaluated from a payer perspective. Costs of surgical procedures and rehabilitation protocols, risks of graft rupture and contralateral ACL injury, risk reductions as a result of the eRTP strategy, and relevant health utilities were derived from the literature. An incremental cost-effectiveness ratio of <$100,000/quality-adjusted life-year was used to determine cost-effectiveness. Sensitivity analyses were performed on pertinent model parameters to assess their effect on base case conclusions. In the base case analysis, the eRTP strategy cost was conservatively estimated to be $969 more than the standard rehabilitation protocol. Completion of the eRTP strategy was considered to confer a 25% risk reduction for graft rupture in comparison with standard rehabilitation.

RESULTS

The eRTP strategy was more cost-effective than standard rehabilitation alone. Based on 1-way threshold analyses, the eRTP strategy was cost-effective as long as its additional cost over standard rehabilitation was <$2092 or the eRTP strategy decreased the incidence of contralateral ACL rupture by >13.8%.

CONCLUSION

The eRTP strategy in this study adds additional neuromuscular retraining and additional physician follow-up-as well as advanced testing goals upon which RTP is contingent-to traditional physical therapy. Our data suggest that these additions are cost-effective, even assuming only modest associated decreases in ACL graft failure. This study also determined that the only variable that had the potential to change the cost-effectiveness conclusion based on predetermined ranges was the additional cost of rehabilitation based on 1-way sensitivity analysis.

CLINICAL RELEVANCE

This study provides evidence of cost-effectiveness for payers, supporting the use of enhanced RTP programs. The sensitivity analyses herein may be used to determine if any given RTP program going forward is cost-effective, regardless of the exact components of the program.

Prevalence of knee injuries among male college students in Riyadh, Kingdom of Saudi Arabia

BACKGROUND

The knee is considered the most common injured joint between young sport participants. However, there is lack of proper prevalence estimation in our population. The purpose of this study was to identify the prevalence of knee injuries among male college students and to observe the demographic data associated with it. Our secondary objective was to evaluate the awareness and knowledge about these injuries.

METHODS

This is a cross-sectional study. A survey was distributed to collect the data among male college students, King Saud University, Riyadh, Saudi Arabia. Out of 688 students who participated and completed the questionnaire, a total of 482 were considered valid and met the inclusion criteria. Data were analyzed using Statistical Package for Social Sciences (SPSS).

RESULTS

The overall prevalence of knee injury was 23.2% (n = 112). Most of them injured during sport activities especially soccer and 68.7% involved in a non-contact mechanism of injury. Among those who went to a hospital mostly were diagnosed as contusion (31.4%) then as meniscus tear, ACL, and collateral ligament injury, respectively. Majority was treated conservatively and only 10.7% needed surgery surprisingly. There was no statistically significant difference between those who are injured and whether they were warmed up and stretched or not (P = 0.619). Low level of knowledge about knee injuries was noticed among the participants 57.7%.

CONCLUSION

Our study has highlighted the high prevalence of knee injuries and the need to raise the level of awareness and knowledge about these injuries in our population. Soccer was the most common sport associated with knee injuries; most of these injuries were treated conservatively.

Awareness of Anterior Cruciate Ligament Injury-Preventive Training Programs Among Female Collegiate Athletes

CONTEXT

Neuromuscular training programs can reduce the rate of noncontact anterior cruciate ligament (ACL) injuries, particularly in female athletes.

OBJECTIVE

To assess the awareness of, experience with, and factors associated with participation in preventive training programs (PTPs) among female collegiate athletes and their knowledge of ACL injuries.

DESIGN

Cross-sectional study.

SETTING

National Collegiate Athletic Association (NCAA) sports programs.

PATIENTS OR OTHER PARTICIPANTS

A total of 440 female NCAA athletes (age = 20 ± 1 years) representing 20 sports during the 2017-2018 academic year.

MAIN OUTCOME MEASURE(S)

We used a 12-item survey to collect data on each participant's age, sport, position, college, NCAA division, and awareness of and experience with PTPs. We performed descriptive statistics and used odds ratios (ORs) to assess relationships between demographic data and awareness of or interest in PTPs.

RESULTS

Of the 440 respondents, 85% (n = 373) knew that female athletes were at higher risk for sustaining ACL injuries than male athletes, and 89% (n = 391) knew that ACL injuries were preventable. Thirty-three percent (n = 143) were familiar with the concept of ACL PTPs. Only 15% (n = 64) had ever performed PTPs, but 89% (n = 391) reported they would perform a daily PTP if it could prevent ACL injuries. Fifty-two of the 64 respondents (81%) who had performed PTPs said athletic trainers or coaches oversaw the PTPs. Participants were more likely to be familiar with ACL PTPs if they (OR = 3.5; 95% confidence interval [CI] = 2.0, 5.8) or a teammate (OR = 4.6; 95% CI = 2.1, 9.8) had sustained an ACL injury. Respondents were more willing to perform PTPs if they (OR = 2.3; 95% CI = 0.80, 6.6) or a teammate (OR = 3.4; 95% CI = 1.8, 6.6) had sustained an ACL injury.

CONCLUSIONS

Although 89% of respondents expressed interest in performing daily ACL PTPs, only 15% had performed such programs, and only 33% were familiar with the concept of ACL PTPs.

Pediatric Sports Injuries

With increasing pediatric participation in organized sport and the early specialization of children in single sports, the number of injuries seen in the pediatric and adolescent athletic population continues to increase. Children experience acute traumatic injuries during practice and competition as well as chronic overuse injuries secondary to the repetitive stress on their developing bodies. The unique nature of the pediatric patient often requires a different diagnostic, prognostic, and treatment approach to sports injuries compared with their adult counterparts.

Fatigue Increases Dynamic Knee Valgus in Youth Athletes: Results From a Field-Based Drop-Jump Test

PURPOSE

To determine whether fatigue increases dynamic knee valgus in adolescent athletes, as measured after a standardized exercise protocol and video-based drop-jump test. A secondary aim was to determine whether individual risk factors place certain athletes at increased risk for dynamic knee valgus.

METHODS

Athletes aged 14 to 18 years were recruited for this video analysis study. Athletes were recorded performing a standard drop-jump to assess dynamic valgus. Participants then completed a standardized exercise protocol. Fatigue was quantified using a maximum vertical jump, which was compared with pre-exercise values. The drop-jump was repeated postexercise. All drop-jump recordings were randomized and scored for dynamic valgus by 11 blinded reviewers. Univariate analysis was performed to identify characteristics that predisposed athletes to increased dynamic valgus.

RESULTS

Eighty-five (47 female, 38 male) athletes with an average age of 15.4 years were included in this study. Forty-nine percent of athletes demonstrated an increase in dynamic valgus determined by drop-jump assessment after exercise. A significantly greater percentage of athletes were graded "medium or high risk" in jumps recorded after the exercise protocol (68%) as compared with before the exercise protocol (44%; P < .01). Female athletes (P < .01) and those older than 15 years of age (P < .01) were the most affected by fatigue.

CONCLUSIONS

In conclusion, our study found that exercise increases dynamic knee valgus in youth athletes. Female athletes and those older than 15 years of age were most significantly affected by exercise. Greater fatigue levels were found to correlate with an increase in dynamic knee valgus, which may place athletes at greater anterior cruciate ligament injury risk. The field-based exercise drop-jump test is a low-cost and reproducible screening tool to identify at-risk athletes who could possibly benefit from anterior cruciate ligament injury-prevention strategies.

LEVEL OF EVIDENCE

III, Comparative trial.

Health State Utilities in Children and Adolescents With Osteochondritis Dissecans of the Knee

Background:

The impact of osteochondritis dissecans (OCD) lesions of the knee on a child’s health-related quality of life has not previously been quantified. Preference-based health utility assessment allows patients to assign quality-of-life valuations (utilities) to different health states and conditions.

Purpose:

To determine (1) patient-reported utility scores for health states associated with pediatric OCD lesions of the knee and (2) whether these scores are associated with patient demographics or disease severity.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Children, adolescents, and young adults being treated for OCD of the knee were interviewed to assess utilities for each of the 6 health states commonly encountered in the treatment of OCD: (1) symptomatic lesion, (2) nonoperative rehabilitation, (3) postoperative rehabilitation, (4) intermediate treatment success, (5) early degenerative knee changes, and (6) successful treatment (asymptomatic). Patients were asked to assign health utilities to each state using a standardized feeling thermometer (scale, 0-100), which were converted to a health state utility (scale, 0-1 [1 = perfect health]). Utilities were reported with descriptive statistics, and comparative analyses were performed to test whether assignments were associated with patient age, sex, or whether the OCD lesion required surgical intervention.

Results:

A total of 100 participants treated or undergoing treatment for OCD were prospectively enrolled; 74% were male (n = 74). The median age at the time of survey was 15 years (interquartile range, 13-16.5 years). Utility scores were as follows: symptomatic OCD lesion, 0.15; nonoperative rehabilitation, 0.30; postoperative rehabilitation, 0.30; early degenerative changes, 0.58; intermediate treatment success, 0.65; and successful treatment, 1.0. Utility scores were not associated with age, sex, or whether the participant underwent surgical treatment for the OCD lesion.

Conclusion:

The current study quantified patient-reported utilities for 6 OCD lesion health states, which may be used for future health-related quality of life, decision analysis, and quality/safety/value studies. These utility scores were stable and not affected by patient age, sex, or treatment strategy.

Posterior cruciate ligament injury is influenced by intercondylar shape and size of tibial eminence

AIMS

Little is known about the risk factors that predispose to a rupture of the posterior cruciate ligament (PCL). Identifying risk factors is the first step in trying to prevent a rupture of the PCL from occurring. The morphology of the knee in patients who rupture their PCL may differ from that of control patients. The purpose of this study was to identify any variations in bone morphology that are related to a PCL.

PATIENTS AND METHODS

We compared the anteroposterior (AP), lateral, and Rosenberg view radiographs of 94 patients with a ruptured PCL to a control group of 168 patients matched by age, sex, and body mass index (BMI), but with an intact PCL after a knee injury. Statistical shape modelling software was used to assess the shape of the knee and determine any difference in anatomical landmarks.

RESULTS

We found shape variants on the AP and Rosenberg view radiographs to be significantly different between patients who tore their PCL and those with an intact PCL after a knee injury. Overall, patients who ruptured their PCL have smaller intercondylar notches and smaller tibial eminences than control patients.

CONCLUSION

This study shows that differences in the shape of the knee are associated with the presence of a PCL rupture after injury. A smaller and more sharply angled intercondylar notch and a more flattened tibial eminence are related to PCL rupture. This suggests that the morphology of the knee is a risk factor for sustaining a PCL rupture. Cite this article: Bone Joint J 2019;101-B:1058-1062.

The design, development, implementation and evaluation of IRISweb; A rugby-specific web-based injury surveillance system

OBJECTIVES

To describe the development, implementation and evaluation of a comprehensive injury surveillance system.

DESIGN

The four phases; i) A survey of 58 medical professionals working in amateur rugby. ii) The design of a web-based injury surveillance system (IRISweb). iii) Recruitment of 21 of the top 58 amateur clubs to use IRISweb. iv) An evaluation survey of the 21 participating clubs.

SETTING

Irish amateur rugby clubs.

PARTICIPANTS

Medical professionals working in amateur rugby.

MAIN OUTCOME MEASURES

Phase one investigated the injury monitoring practices in operation prior to the IRIS project. Phase four investigated the effectiveness and usefulness of IRISweb.

RESULTS

Twenty-one clubs were recruited, however 2 clubs failed to provide a full season of data (10% dropout rate). Eighty-two percent of the remaining 19 clubs rated IRISweb as 'good' or 'very good'. Facilitators of injury surveillance were; increased player adherence (65%) and notifications to update the system (59%), however, poor player adherence (71%) and medical staff availability (24%) were the main barriers.

CONCLUSIONS

The IRIS project is the first prospective long-term injury surveillance system in Irish amateur rugby, effectively tracking injuries to guide future evidence-based injury prevention strategies. This study highlights facilitators and barriers to injury surveillance within amateur sport.

Exercise-Based Knee and Anterior Cruciate Ligament Injury Prevention

The Academy of Orthopaedic Physical Therapy and the American Academy of Sports Physical Therapy have an ongoing effort to create evidence-based clinical practice guidelines (CPGs) for orthopaedic and sports physical therapy management and prevention of musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability and Health (ICF). This particular guideline focuses on the exercise-based prevention of knee injuries. J Orthop Sports Phys Ther. 2018;48(9):A1-A42. doi:10.2519/jospt.2018.0303.

Genetic Variants and Anterior Cruciate Ligament Rupture: A Systematic Review

Background

Studies have shown a familial predisposition for anterior cruciate ligament (ACL) rupture and have been followed by genetic-association studies on polymorphisms in candidate genes in recent years. To date, no systematic review with a best-evidence synthesis has evaluated the influence of genetics on this devastating knee injury.

Objective

Our objective was to evaluate the association between genetic variants and ACL rupture.

Methods

We performed an extensive search in Embase, MEDLINE, Web of Science, Scopus, PubMed Publisher, Cochrane Register of Clinical Trials, and Google scholar up to 24 August 2015. Studies were eligible if they met the following inclusion criteria: (1) design was a case–control study, retrospective or prospective follow-up study, or a randomized controlled trial (RCT); (2) the study examined the association between a genetic variant and ACL rupture in both an ACL and a control group. We determined the risk of bias for all included studies.

Results

We included a total of 16 studies (eight at high risk of bias and eight with an unclear risk) that examined 33 different DNA variants. Conflicting evidence was found for the COL1A1 rs1800012 and COL3A1 rs1800255 variants, whereas limited evidence was found for no association of the COL5A1 rs12722 and rs13946 and COL12A1 rs970547 variants (all encoding collagen). Evidence was insufficient to draw conclusions as to whether any other genetic variant identified in this review had any association with ACL rupture.

Conclusions

More research is needed to support a clear association between ACL rupture and genetic variants. Genome-wide studies are recommended for exploring more potential genetic variants. Moreover, large prospective studies are needed to draw robust conclusions.

An Increased Lateral Femoral Condyle Ratio Is a Risk Factor for Anterior Cruciate Ligament Injury

BACKGROUND

The purpose of this study was to examine the relationship between distal femoral morphology and anterior cruciate ligament (ACL) injury, ACL reconstruction (ACLR) failure, and contralateral ACL injury. It was hypothesized that increased posterior femoral condylar depth, quantified as the lateral femoral condyle ratio, would correlate with increased risk of primary ACL injuries, ACLR failures, and contralateral ACL injuries.

METHODS

The charts of consecutive patients who underwent arthroscopic knee surgery at an academic medical center from 2012 to 2016 with minimum follow-up of 24 months were retrospectively reviewed. Patients were stratified into 4 groups: (1) a control group of patients with no ACL injury, (2) patients with primary ACL injury, (3) patients with failed ACLR, and (4) patients with previous ACL injury and subsequent contralateral ACL injury. With use of lateral radiographs, the ratio of posterior femoral condylar depth to total condylar length was defined as the lateral femoral condyle ratio. Differences between study groups were identified with use of analysis-of-variance (ANOVA) and post-hoc testing with significance set at p < 0.05. Receiver operating characteristic (ROC) curve analysis was performed to determine the optimal cutoff for detecting increased risk of ACL injury.

RESULTS

Two hundred patients met the inclusion criteria. The mean lateral femoral condyle ratios (and standard deviations) were 61.2% ± 2.4% in the control group, 64.2% ± 3.8% in the primary ACL injury group, 64.4% ± 3.6% in the failed ACLR group, and 66.9% ± 4.3% in the contralateral ACL injury group. Patients who had a primary ACL injury, failed ACLR, or contralateral ACL injury had significantly higher ratios compared with the control group (p < 0.008). ROC curve analysis demonstrated that a lateral femoral condyle ratio of >63% was associated with an increased risk for ACL injury, with a sensitivity of 77% and a specificity of 72%.

CONCLUSIONS

The data from this study show that increased posterior femoral condylar depth, quantified as the lateral femoral condyle ratio, is associated with an increased risk of ACL injury, including primary and contralateral ACL injuries. The data from this study may help clinicians to identify patients at a greater risk of ACL injury.

LEVEL OF EVIDENCE

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

What's New in Pediatric and Adolescent Anterior Cruciate Ligament Injuries?

BACKGROUND

Anterior cruciate ligament (ACL) tears in children and adolescent patients are being diagnosed and treated at an ever-increasing rates. We performed a review of recent literature regarding care of children and adolescent athletes with an ACL injury.

METHODS

PubMed database was searched for all papers related to treatment of children and adolescents with ACL injuries from October 1, 2012 to September 30, 2015, yielding 114 publications.

RESULTS

A total of 59 papers were found to have contributed important new findings. Papers were selected based on new findings in the following categories: epidemiology, anatomy, risk factors, sex disparity, prevention, surgical outcomes, timing and associated pathologies, and rehabilitation and return to sport.

CONCLUSIONS

Pediatric ACL injuries continue to rise and there are multiple surgical procedures that restore clinical function with good outcomes. Early surgical treatment is favored to prevent concomitant articular injuries. Early return to play can increase risk of reinjury and should be met with caution in this age group. Prevention strategies should be further studied and implemented in hopes of decreasing the incidence of this injury and the long-term potential damage.

LEVEL OF EVIDENCE

Level 4-titerature review.

Challenges in the Management of Anterior Cruciate Ligament Ruptures in Skeletally Immature Patients

Although initially considered rare, anterior cruciate ligament (ACL) ruptures in pediatric patients recently have increased substantially as a result of greater awareness of the injury and increased participation in youth sports. Although pediatric patients with an ACL injury and a clinically stable joint may handle the injury well and return to sports activity without requiring surgical reconstruction, young, active patients with an ACL rupture and an unstable joint may be good candidates for ACL reconstruction to prevent ongoing instability and additional joint damage. ACL reconstruction techniques have been developed to prevent physeal injury in skeletally immature patients. The surgical treatment of skeletally immature patients with an ACL rupture may differ from that of adults with an ACL rupture and presents unique challenges with regard to reconstruction technique selection, graft preparation, rehabilitation, and return to sports activity. Orthopaedic surgeons should understand various physeal-sparing ACL reconstruction techniques and the general challenges associated with the surgical management of ACL ruptures in pediatric patients.