Injury initiates unfavourable weight gain and obesity markers in youth

Adolescents' experience with sports-related pain and injury: A systematic review of qualitative research

OBJECTIVE

The aim of this review is to synthesise qualitative studies examining adolescents' experience with pain and injury arising from sports participation.

METHODS

This review was registered on Open Science Framework prior to data extraction. A systematic search of PubMed, Embase, and SPORTDiscus was conducted. Studies were appraised using the CASP (critical appraisal skills programme) checklist. Data was synthesised using a meta aggregation.

STUDY SELECTION CRITERIA

Inclusion criteria included studies related to adolescents aged 14-19yrs with sports related pain/injury, employed a qualitative design, full text publications in English.

RESULTS

Sixteen studies of 216 participants were included. Studies investigated severe knee injuries, concussion, or other musculoskeletal injuries. Synthesised findings show that, regardless of injury type, adolescents experience a mix of positive (motivation to rehab and return to sport, optimism) and negative emotions (fear of re-injury, isolation, depressive responses) throughout recovery. Common coping strategies were to ignore symptoms, modify activity levels, or seek support.

CONCLUSION

Sports-related pain and injury has a multifaceted effect on the adolescent athlete. There is a pervasive fear of re-injury and social isolation, but the desire to return to sports is facilitated through motivation and support. Peer motivation effects the willingness of the adolescent to persist with rehabilitation.

Longitudinal changes in adiposity following anterior cruciate ligament reconstruction and associations with knee symptoms and function

Objective

To evaluate adiposity after anterior cruciate ligament reconstruction (ACLR): i) cross-sectionally (1-year post-ACLR) compared to uninjured controls; ii) longitudinally up to 5 years post-ACLR; and iii) associations with patient-reported symptoms and physical performance.

Methods

In 107 individuals post-ACLR and 19 controls, we assessed global (BMI), peripheral (subcutaneous adipose tissue thickness on the posteromedial side of knee MRI), and central (waist circumference in ACLR group) adiposity. Patient-reported symptoms (Knee injury and Osteoarthritis Outcome Score) and physical performance (hop for distance) were evaluated at 1 and 5 years post-ACLR. Linear regression models evaluated adiposity between groups. Paired t-tests evaluated changes in adiposity from 1- to 5 years post-ACLR. Linear regression models analyzed adiposity's associations with patient-reported symptoms and physical performance at 1-year post-ACLR, changes in symptoms and performance over 4 years post-ACLR, and longitudinal changes in adiposity and symptoms and performance, controlling for age, sex, and activity level.

Results

Individuals 1-year post-ACLR were associated with higher average global (3 ​kg/m2) and peripheral adiposity (2.3 ​mm). From 1- to 5 years post-ACLR, higher average global (0.58 ​kg/m2) and central (5 ​cm) adiposity, and lower average peripheral adiposity (1.3 ​mm) were observed. In general, adiposity at one-year post-ACLR was negatively associated with patient-reported symptoms and physical performance, and changes from 1 to 5 years post-ACLR. Increases in adiposity were negatively associated with changes in patient-reported symptoms and physical performance over four years post-ACLR.

Conclusion

Greater global and central adiposity is a feature of young adults following ACLR and influences current and future patient-reported symptoms and physical performance.

The association between lower limb fractures and weight gain in adults: a prospective analysis of body mass index trends

PURPOSE

Despite understanding the connection between obesity and fracture risk, there is limited research on the implications of lower limb fractures on subsequent changes in body mass index (BMI). Our study aimed to assess the impact of lower limb fractures on BMI alterations over an 18-month period.

METHODS

A multi-center, prospective cohort study was conducted between January 2021 to June 2023, involving 494 adults with lower limb fractures. Participants were recruited within 2 weeks post-injury and were assessed for demographics, injury details, and weight at seven distinct time points. By 18 months, the primary outcome was the mean weight gain.

RESULTS

The average age of the participants was 39 (± 12.7) with a baseline weight and BMI of 80.4 kg and 27.6, respectively. At the 18-month follow-up, 75% of patients experienced an average weight increase in 4 kg (± 5.39 kg), equating to a BMI rise of 1.39 (± 1.88). Most patients attributed weight changes to their injury, with nearly half expressing distress from their weight change. Only 37% believed that they had resumed their previous activity levels by the final follow-up. Approximately 31% of the patients sought some form of external weight management care in the form of nutritionist advice, training programs, medication and weight management procedures.

CONCLUSIONS

Lower limb fractures significantly affect weight gain over an 18-month period, with substantial psychological and physical consequences. Healthcare providers should anticipate potential weight gain post-fracture and incorporate strategies addressing both physical and mental aspects of rehabilitation to enhance recovery outcomes. Early and even immediate weight bearing may play a pivotal role in mitigating weight changes and returning the patient to their previous level of activity. Further detailed studies focusing on different fractures and postoperative interventions are recommended.

Lower Extremity Strength Relative to Body Mass in Pediatric Female Athletes: Implications for Anterior Cruciate Ligament Injury

This study compared lower extremity (LE) muscular strength by 3 groups of female athletes using chronological age and consideration of age of peak height velocity (PHV). Isometric quadriceps, hamstrings, and hip abductors strength were assessed from physically active, pediatric females. The body mass normalized isometric strength (N m/kg) was compared by the 3 age groups. There were 388 young female athletes (<10 years [14.2%], 11-14 years [48.7%], and 15-18 years [37.1%]). The body mass normalized LE strength was lower in 11-14 years compared with <10 years (quadriceps [P = .001], hamstrings [P = .001], and hip abductors [P = .037]) as well as in 15-18 years relative to <10 years in quadriceps (P = .001) and hamstrings (P = .001). The analysis results were consistent with both chronological age alone and incorporating effects of age of PHV. In short, body mass normalized LE strength (quadriceps, hamstrings, and hip abductors) of 11-14 years females was lower than <10 years females.

Elective musculoskeletal surgery is associated with postoperative weight changes in pediatric and adolescent patients

Purpose

Patients of elective orthopedic surgeries often reduce activity levels during postoperative recovery. It is unclear whether these extended periods of modified activities lead to weight changes. The purpose of this study was to evaluate changes in body mass index percentile in pediatric patients over 2.5 years following primary musculoskeletal surgeries.

Methods

Institutional records for utilized current procedural terminology codes were used to identify patients aged 21 years or younger who underwent elective surgery at a single pediatric orthopedic institution between October 2016 and December 2018. Non-primary surgeries and patients without preoperative body mass index measurements were excluded. Demographic characteristics, height, weight, and body mass index within 30 months of surgery were collected. Body mass index relative to age was calculated. Analysis of body mass index changes at follow-up intervals of 3-7, 9-18, and 24-30 months after surgery was performed for the overall sample, within surgical categories, and within preoperative weight classifications.

Results

A total of 1566 patients (53.1% female, average age 12.4 years) were included. Over one-third of patients were overweight or obese at presentation. The average change in body mass index percentile relative to baseline was increased at all follow-up intervals. Values reached significance at 9-18 months (p = .002) and 24-30 months (p = .001). While underweight and normal-weight patients had increased body mass index at all three timepoints, overweight or obese patients decreased.

Conclusions

Patients undergoing elective orthopedic procedures may experience significant changes in body mass index percentile postoperatively. At extremes of weight, patients experience improvement toward the mean, but most patients may undergo body mass index increases beyond what would be expected during normal growth.

Level of evidence

Retrospective level III.

Weight Changes in Young Service Members After Lower Limb Amputation: Insights From Group-Based Trajectory Modeling

INTRODUCTION

Weight gain can contribute to osteoarthritis, cardiovascular disease, low back pain, and poor health-related quality of life. Weight trajectory patterns have been described in older veterans with limb loss; however, there is limited evidence of changes in weight in younger veterans with limb loss.

MATERIALS AND METHODS

Service members with unilateral or bilateral lower limb amputations (LLAs) (and without an upper limb amputation) were included in this retrospective cohort analysis (n = 931). The mean postamputation baseline weight was 78.0 ± 14.1 kg. Bodyweight and sociodemographic data were extracted from clinical encounters within electronic health records. Group-based trajectory modeling assessed weight change patterns 2 years postamputation.

RESULTS

Three weight change trajectory groups were identified: 58% (542 of 931) of the cohort had stable weight, 38% (352 of 931) had weight gain (mean gain = 19.1 kg), and 4% (31 of 931) had weight loss (mean loss = 14.5 kg). Individuals with bilateral amputations were more frequently noted in the weight loss group compared with those with unilateral amputations. Individuals with LLAs because of trauma other than blasts were more frequently found in the stable weight group compared with those with amputations because of disease or a blast. Younger individuals (<20 years old) with amputations were more likely to be in the weight gain group compared with older individuals.

CONCLUSIONS

More than half the cohort maintained a stable weight for two years after amputation, and more than a third experienced weight gain during the same time frame. Knowledge of underlying factors that were associated with weight gain could inform preventative strategies for young individuals with LLAs.

Let's talk about sex (and gender) after ACL injury: a systematic review and meta-analysis of self-reported activity and knee-related outcomes

OBJECTIVE

Investigate sex/gender differences in self-reported activity and knee-related outcomes after anterior cruciate ligament (ACL) injury.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

Seven databases were searched in December 2021.

ELIGIBILITY CRITERIA

Observational or interventional studies with self-reported activity (including return to sport) or knee-related outcomes after ACL injury.

RESULTS

We included 242 studies (n=123 687, 43% females/women/girls, mean age 26 years at surgery). One hundred and six studies contributed to 1 of 35 meta-analyses (n=59 552). After ACL injury/reconstruction, very low-certainty evidence suggests females/women/girls had inferior self-reported activity (ie, return to sport, Tegner Activity Score, Marx Activity Scale) compared with males/men/boys on most (88%, 7/8) meta-analyses. Females/women/girls had 23%-25% reduced odds of returning to sport within 1-year post-ACL injury/reconstruction (12 studies, OR 0.76 95% CI 0.63 to 0.92), 1-5 years (45 studies, OR 0.75 95% CI 0.69 to 0.82) and 5-10 years (9 studies, OR 0.77 95% CI 0.57 to 1.04). Age-stratified analysis (<19 years) suggests female athletes/girls had 32% reduced odds of returning to sport compared with male athletes/boys (OR 0.68, 95% CI 0.41 to 1.13, I² 0.0%). Very low-certainty evidence suggests females/women/girls experienced inferior knee-related outcomes (eg, function, quality of life) on many (70%, 19/27) meta-analyses: standardised mean difference ranging from -0.02 (Knee injury and Osteoarthritis Outcome Score, KOOS-activities of daily living, 9 studies, 95% CI -0.05 to 0.02) to -0.31 (KOOS-sport and recreation, 7 studies, 95% CI -0.36 to -0.26).

CONCLUSIONS

Very low-certainty evidence suggests inferior self-reported activity and knee-related outcomes for females/women/girls compared with males/men/boys after an ACL injury. Future studies should explore factors and design targeted interventions to improve outcomes for females/women/girls.

PROSPERO REGISTRATION NUMBER

CRD42021205998.

Knee pain in young sports players aged 6-15 years: a cross-sectional study in Japan

BACKGROUND

Knee is the most commonly injured part of the body in young athletes. Knee pain in several studies have been seen to be more prevalent in active adolescents compared to inactive, although common in both groups. Nevertheless, few studies with large sample size have been published reporting the difference of the prevalence of knee pain for each sport among young sports players. This study investigated the point prevalence of knee pain among young sports players aged 6-15 years old according to age, sex, and sports discipline. Furthermore, this study investigated the association between knee pain and sports discipline among young sports players.

METHODS

A cross-sectional study was conducted using a self-reported questionnaire on young sports players aged 6-15 years from the Miyagi Amateur Sports Association. Multivariable logistic regression models were used to examine the association between knee pain and sports discipline and were adjusted for age, sex, body mass index (BMI), training days per week, and training hours per weekday and weekend.

RESULTS

A total of 7234 young sports players were included. The point prevalence of knee pain was 10.9%. Females (13.3%) had more knee pain than males (9.8%). Young, 13-year-old sports players had the highest prevalence of knee pain (19.1%). The multivariable analysis showed that the highest odds ratio [95% confidence interval] was observed for handball players (2.42 [1.01-5.81]). In addition, hand ball, mini-basketball (odds ratio 1.85; 95% CI 1.38-2.47), and basketball (odds ratio 1.66; 95% CI 1.23-2.26) were significantly associated with knee pain, compared with football. The lowest odds ratio was observed for swimming (0.34 [0.05-2.54]), followed by karate (odds ratio 0.38; 95% CI 0.16-0.89) and baseball (odds ratio 0.47; 95% CI 0.35-0.64).

CONCLUSION

The prevalence of knee pain among young athletes differed according to age, sex, and sports discipline. Their parents and clinicians should recognize this information to manage knee pain among young sports players.

Do Weightbearing Restrictions Cause Excess Weight Gain in Children With LEGG-Calvé-Perthes Disease?

BACKGROUND

Restricted weight bearing is commonly prescribed in Legg-Calvé-Perthes Disease (LCPD), raising concerns of causing overweight or obesity. This study utilizes prospectively collected data to address the following questions: (1) does body mass index (BMI) Z-score increase over the course of LCPD follow-up; (2) is having a BMI category of normal, overweight, or obese at baseline associated with BMI Z-score changes over the course of follow-up; and (3) is the duration of weight bearing restrictions (no restrictions, <3, 3 to <6, 6 to 9, or >9 mo) associated with BMI Z-score changes.

METHODS

Data of 130 children aged 5 to 12 years with unilateral early-stage LCPD were extracted from an international database. Nation-specific BMI Z-scores and percentile-based weight categories were determined, and the duration of follow-up and weight bearing restrictions were calculated. Longitudinal changes in BMI Z-scores were evaluated for the 3 study questions using mixed effects linear regression models with surgery as a covariate. Sensitivity analyses were used to determine the influence of socio-cultural background (USA vs. India) for each study question.

RESULTS

During the 35.5±15.9 months of follow-up, no statistically significant increase in BMI Z-scores was observed across the entire cohort, or following stratification by baseline weight categories or the duration of the weight bearing restriction. Sensitivity analyses indicated that patients in the USA had no change in their BMI Z-score. When stratified by weight categories, the normal weight of US children had a small increase in their BMI Z-score (0.005 per mo, 95% confidence interval: 0.0002, 0.009), but this was not seen in other BMI categories. The cohort of Indian children had a small but significant decrease in their BMI Z-score (-0.005/mo, 95% CI: -0.009, -0.0002). After stratification by weight categories, a small decrease of the BMI Z-score was observed only in the Indian overweight children (-0.016 per mo, 95% CI: -0.027, -0.005) and no other BMI category.

CONCLUSIONS

Weightbearing restrictions over the course of follow-up for our cohort of children with early-stage LCPD were not associated with clinically meaningful increases of BMI Z-scores. Weight gain is multi-factorial and probably not caused by weight bearing restrictions alone.

LEVEL OF EVIDENCE

III Diagnostic Study.

Environmental Risk Factors for Osteoarthritis: The Impact on Individuals with Knee Joint Injury

Osteoarthritis is a debilitating chronic condition involving joint degeneration, impacting over 300 million people worldwide. This places a high social and economic burden on society. The knee is the most common joint impacted by osteoarthritis. A common cause of osteoarthritis is traumatic joint injury, specifically injury to the anterior cruciate ligament. The purpose of this review is to detail the non-modifiable and modifiable risk factors for osteoarthritis with particular focus on individuals after anterior cruciate ligament injury. After reading this, health care providers will better comprehend the wide variety of factors linked to osteoarthritis.

The Effects of Early Physiotherapy Treatment on Musculoskeletal Injury Outcomes in Military Personnel: A Narrative Review

The risks and incidence rates of musculoskeletal injuries among military personnel are high, and the importance of physiotherapy in treating these injuries is well established. However, what is less clear is whether the timing of commencement of physiotherapy treatment affects musculoskeletal injury outcomes in military personnel. This lack of clarity is exacerbated by the known underreporting of injuries among military personnel, and the resulting self-management of musculoskeletal injuries using analgesics, non-steroidal anti-inflammatories and other means. This narrative review was designed to identify and synthesize current evidence regarding the effects of timing of physiotherapy treatment on musculoskeletal injury outcomes, focusing on potential benefits of early versus typical or delayed commencement of physiotherapy treatment. Overall, current evidence suggests early physiotherapy treatment of musculoskeletal injuries offers distinct advantages over typical or delayed commencement of physiotherapy treatment in military settings. Specifically, it appears early treatment expedites recovery in early phases following injury onset and benefits longer term mental health and well-being. It may also reduce the need for more invasive and costly health care interventions and enable earlier return to training and operational service. Importantly, a cultural shift within military contexts to ensure early reporting of musculoskeletal injuries is required if the benefits of early commencement of physiotherapy treatment are to be achieved.

Cross-sectional study of gender differences in physical activity-related injuries amongst Chinese college students majoring in rehabilitation

The main objective of the paper was to explore the potential risk factors for physical activity-related injuries (PARI) amongst college students majoring in rehabilitation and to analyse gender differences. A random whole group sampling method was used to recruit freshmen to seniors aged 15-25 years from over 90 universities in China that offer rehabilitation. The total number of people included was 6,032, of which 1,989 were male and 4,043 were female. The underlying risk factors for PARI of different genders were assessed using a structured self-management questionnaire including sociodemographic characteristics, physical activity levels, risk-taking and protective behaviors, and PARI. Totally 6,032 questionnaires were obtained for final analysis, with 792 total number of injured persons (415 males, 377 females), the sum of the cumulative frequency of injuries to injured persons is 1,607 (881 males, 726 females) and a PARI risk of 0.27 (males: 0.44, females: 0.18; p < 0.001; sum of the cumulative frequency of injuries/total number of people surveyed/year). For male and female students, participation in sports teams, having a high level of PA as well as with antisocial behavior were risk factors for developing PARI. Regarding female students, regional differences was associated with elevated odds to suffer from PARI. The prevalence rates of PARI vary between male and female students. The research subjects were university students in rehabilitation. Compared to general college students, rehabilitation students have a certain knowledge base related to injuries, which defines the specificity and research value of this subjects. This study provides guidance for reducing PARI in students in rehabilitation and may provide a basis for developing future injury prevention mechanisms for university students in general.

Atypical Lower Limb Mechanics During Weight Acceptance of Stair Descent at Different Time Frames After Anterior Cruciate Ligament Reconstruction

BACKGROUND

An anterior cruciate ligament (ACL) rupture may result in poor sensorimotor knee control and, consequentially, adapted movement strategies to help maintain knee stability. Whether patients display atypical lower limb mechanics during weight acceptance of stair descent at different time frames after ACL reconstruction (ACLR) is unknown.

PURPOSE

To compare the presence of atypical lower limb mechanics during the weight acceptance phase of stair descent among athletes at early, middle, and late time frames after unilateral ACLR.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 49 athletes with ACLR were classified into 3 groups according to time after ACLR-early (<6 months; n = 17), middle (6-18 months; n = 16), and late (>18 months; n = 16)-and compared with asymptomatic athletes (control; n = 18). Sagittal plane hip, knee, and ankle angles; angular velocities; moments; and powers were compared between the ACLR groups' injured and noninjured legs and the control group as well as between legs within groups using functional data analysis methods.

RESULTS

All 3 ACLR groups showed greater knee flexion angles and moments than the control group for injured and noninjured legs. For the other outcomes, the early group had, compared with the control group, less hip power absorption, more knee power absorption, lower ankle plantarflexion angle, lower ankle dorsiflexion moment, and less ankle power absorption for the injured leg and more knee power absorption and higher vertical ground reaction force for the noninjured leg. In addition, the late group showed differences from the control group for the injured leg revealing more knee power absorption and lower ankle plantarflexion angle. Only the early group took a longer time than the control group to complete weight acceptance and demonstrated asymmetry for multiple outcomes.

CONCLUSION

Athletes with different time frames after ACLR revealed atypically large knee angles and moments during weight acceptance of stair descent for both the injured and the noninjured legs. These findings may express a chronically adapted strategy to increase knee control. In contrast, atypical hip and ankle mechanics seem restricted to an early time frame after ACLR.

CLINICAL RELEVANCE

Rehabilitation after ACLR should include early training in controlling weight acceptance. Including a control group is essential when evaluating movement patterns after ACLR because both legs may be affected.

'Such a massive part of rehab is between the ears'; barriers to and facilitators of anterior cruciate ligament reconstruction rehabilitation: a qualitative focus group analysis

Background

Current evidence demonstrates that few patients complete anterior cruciate ligament reconstruction rehabilitation according to evidence-based guidelines. It is important to investigate the viewpoints of our patients to identify patient-reported barriers and facilitators of anterior cruciate ligament reconstruction rehabilitation. Qualitative analysis can provide insight into potential methods for improving the delivery of rehabilitation services.

Methods

In this qualitative study, utilising a social constructionism orientation, viewed through the social phenomenological lens, three focus groups were conducted with individuals 1–20 years post anterior cruciate ligament reconstruction (n = 20, 9 males, 11 females, mean 6.5 years post-surgery, 19–51 years old). Utilising a semi-structured interview guide, participants were asked about their experiences during anterior cruciate ligament reconstruction rehabilitation. Focus groups were recorded, transcribed, and coded using an inductive semantic thematic analysis methodology.

Results

Five organising themes were identified (consisting of 19 sub-themes) to provide a framework to present the data: psychological, physiological, rehabilitation service, rehabilitation characteristics, and interaction with others. Each theme details aspects of rehabilitation, such as exercise delivery, informational support, frequency, and duration of care, kinesiophobia, weight management and interactions with teams and coaches, which present barriers or facilitators for patients to adhere to and participate in rehabilitation. Example quotes are provided for each theme to provide context and the patient’s voice.

Conclusions

This qualitative investigation identified key aspects of a patient's rehabilitation in which they encounter a variety of barriers and facilitators of ACL reconstruction rehabilitation. These aspects, such as the rehabilitation characteristics, service delivery, psychological and physiological factors, and interactions with others, were consistently identified by this cohort as factors which affected their rehabilitation. The themes may provide targets for clinicians to improve rehabilitation and deliver patient-centred care. However, the themes must be evaluated in future trials to assess whether interventions to remove barriers or enhance facilitators improves subsequent outcomes such as return to sport and re-injury rates.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-022-00499-x.

Fear of Reinjury Following Surgical and Nonsurgical Management of Anterior Cruciate Ligament Injury: An Exploratory Analysis of the NACOX Multicenter Longitudinal Cohort Study

OBJECTIVES

The purpose of this study was to compare fear and certainty of reinjury between follow-up time points and treatment groups (no anterior cruciate ligament [ACL] reconstruction [no ACLR], pre-ACLR, post-ACLR) and to identify prognostic factors for fear of reinjury at 3 and 12 months following injury or ACLR.

METHODS

An exploratory analysis of the Natural Corollaries and Recovery After ACL-injury multicenter longitudinal cohort study was conducted. Patients (n = 275) with primary ACL injury and 15 to 40 years of age received usual care (initial physical therapist-supervised rehabilitation, before considering ACLR). Fear of reinjury (as measured with the Anterior Cruciate Ligament Quality of Life instrument [ACL-QOL] item 31 and the Anterior Cruciate Ligament Return to Sport After Injury instrument [ACL-RSI] item 9) and certainty of reinjury (as measured with the Knee Self-Efficacy Scale item D2) were evaluated at baseline and at 3, 6, and 12 months following ACL injury or ACLR. Comparisons were performed with linear mixed models. Linear regression assessed potential prognostic factors (age, sex, preinjury activity, baseline knee function, baseline general self-efficacy, and expected recovery time) for fear of reinjury (ACL-QOL item 31) at the 3- and 12-month follow-up assessments.

RESULTS

Fear of reinjury was common regardless of ACL treatment. Fear of reinjury decreased between 3 and 6 months and 3 and 12 months (mean difference: ACL-QOL = 9 [95% CI = 2 to 15]; ACL-RSI = 21 [95% CI = 13 to 28]) after injury. This improvement was not observed in patients who later underwent ACLR, who reported worse fear of reinjury at 3 months (ACL-QOL = 10 [95% CI = 3 to 18]) and at 12 months (ACL-RSI = 22 [95% CI = 2 to 42]) postinjury compared with those who did not proceed to ACLR. Following ACLR, fear of reinjury decreased between the 3- and 12-month follow-up assessments (ACL-QOL = 10 [95% CI = 4 to 16]; ACL-RSI = 12 [95% CI = 5 to 19]). Greater baseline general self-efficacy was associated with reduced fear of reinjury at 12 months after injury (adjusted coefficient = 1.7 [95% CI = 0.0 to 3.5]). Female sex was related to more fear of reinjury 3 months after ACLR (-14.5 [95% CI = -25.9 to -3.1]), and better baseline knee function was related to reduced fear of reinjury 12 months after ACLR (0.3 [95% CI = 0.0 to 0.7]).

CONCLUSION

People who had ACLR reported worse fear of reinjury before surgery than those who did not proceed to ACLR. Different prognostic factors for fear of reinjury were identified in people treated with ACLR and those treated with rehabilitation alone.

IMPACT

Fear of reinjury is a concern following ACL injury. Clinicians should evaluate and address reinjury fears. These results may assist in identifying individuals at risk of fear of reinjury following surgical and nonsurgical management of ACL injury.

Pediatric Obesity and Sports Medicine: A Narrative Review and Clinical Recommendations

OBJECTIVE

To review what is known about sports medicine and pediatric obesity, with a focus on injuries and MSK concerns.

DATA SOURCES

Systematically searched MEDLINE (PubMed) for all years, using search combinations to best identify potential publications. Manuscripts were reviewed, summarized, and discussed in detail. Experienced clinicians in sports medicine and pediatric obesity reviewed the final searches for substantive content. Inclusion criteria include English language publications, children ≤18 years old, related to the practice of sports medicine and pediatric obesity. Publications excluded that dealt with non-sports medicine aspects of pediatric obesity, such as increasing physical activity or exercise, or the prevention or treatment of obesity.

MAIN RESULTS

Twenty-eight publications were included for review. Papers fell into 5 groupings: (1) MSK-increased incidence of MSK injury in children with obesity, hypothesized to be a result of changes in biomechanics; (2) weight management-gradual loss while maintaining proper hydration and nutrition for sports performance; (3) fitness/conditioning-children with overweight/obese showed decreased fitness measures and cardiopulmonary conditioning; (4) exertional heat illness-a concern for adolescent athletes with obesity, specifically in football; and (5) differential diagnoses-3 key differential diagnoses were identified for increased awareness: slipped capital femoral epiphysis, Blount's disease, and pes planus. Clinical topics pertinent to sports medicine and pediatric obesity were discussed.

CONCLUSIONS

Sports medicine clinicians should be aware of the common MSK and sports-related conditions in children with obesity. Few studies have focused investigations on issues related to children with obesity participating in sports and other physical activities.

Effects of BMI on Walking Speed and Gait Biomechanics after Anterior Cruciate Ligament Reconstruction

PURPOSE

History of an anterior cruciate ligament reconstruction (ACLR) and high body mass index (BMI) are strong independent risk factors for knee osteoarthritis (KOA) onset. The combination of these risk factors may further negatively affect joint loading and KOA risk. We sought to determine the combined influence of BMI and ACLR on walking speed and gait biomechanics that are hypothesized to influence KOA onset.

METHODS

Walking speed and gait biomechanics (peak vertical ground reaction force [vGRF], peak vGRF instantaneous loading rate [vGRF-LR], peak knee flexion angle, knee flexion excursion [KFE], peak internal knee extension moment [KEM], and peak internal knee abduction moment [KAM]) were collected in 196 individuals with unilateral ACLR and 106 uninjured controls. KFE was measured throughout stance phase, whereas all other gait biomechanics were analyzed during the first 50% of stance phase. A 2 × 2 ANOVA was performed to evaluate the interaction between BMI and ACLR and main effects for both BMI and ACLR on walking speed and gait biomechanics between four cohorts (high BMI ACLR, normal BMI ACLR, high BMI controls, and normal BMI controls).

RESULTS

History of an ACLR and high BMI influenced slower walking speed (F1,298 = 7.34, P = 0.007), and history of an ACLR and normal BMI influenced greater peak vGRF-LR (F1,298 = 6.56, P = 0.011). When evaluating main effects, individuals with an ACLR demonstrated lesser KFE (F1,298 = 7.85, P = 0.005) and lesser peak KEM (F1,298 = 6.31, P = 0.013), and individuals with high BMI demonstrated lesser peak KAM (F1,297 = 5.83, P = 0.016).

CONCLUSION

BMI and history of ACLR together influence walking speed and peak vGRF-LR. History of an ACLR influences KFE and peak KEM, whereas BMI influences peak KAM. BMI may need to be considered when designing interventions aimed at restoring gait biomechanics post-ACLR.

Limiting the Risk of Osteoarthritis After Anterior Cruciate Ligament Injury: Are Health Care Providers Missing the Opportunity to Intervene?

OBJECTIVE

To understand what sports orthopedic surgeons (OS), primary care physicians (PCPs) with sports medicine training, and physical therapists (PTs) managing nonelite athletes with anterior cruciate ligament (ACL) injury tell their patients about their osteoarthritis (OA) risk.

METHODS

An electronic survey was distributed by the Canadian Academy of Sport and Exercise Medicine (PCPs, OS), the Sports and Orthopedic Divisions of the Canadian Physiotherapy Association (PTs), and to OS identified through the Royal College of Physicians and Surgeons and the Canadian Orthopaedic Association. The survey included 4 sections: demographics, factors discussed, timing of discussions, and discussion of risk factors and their management. Proportions or means with 95% confidence intervals were calculated.

RESULTS

A total of 501 health care professionals (HCPs) responded (98 PCPs, 263 PTs, and 140 OS). Of those responding, 70-77% of physicians reported always discussing OA risk, but only 35% of PTs did. All HCPs reported that patient activities perceived as detrimental to knee health, ACL reinjury, and simultaneous injury to other structures in the knee were most often the reason for discussing OA risk. OA risk was discussed at initial management post-injury (65-94%), with few discussing risk subsequently. Eighty percent of physicians and 99% of PTs indicated that PTs were suited to provide OA risk and management information.

CONCLUSION

HCPs routinely managing people with ACL injury do not consistently discuss OA risk post-injury with them. Educational strategies for HCPs are urgently needed to develop care pathways inclusive of support for OA risk management following ACL injury.

Chaos and confusion with confidence: Managing fear of Re-Injury after anterior cruciate ligament reconstruction

OBJECTIVES

To explore strategies enabling competitive athletes to manage re-injury fears or anxieties, facilitating return to competitive sport following anterior cruciate ligament reconstruction (ACLR).

DESIGN

Qualitative study.

SETTING

University.

PARTICIPANTS

Ten athletes with ACLR within the last 5 years who had returned to competitive sport with a minimum 7/10 Tegner Activity score.

METHODS

Semi-structured interviews, recorded, transcribed and analysed using interpretive description.

RESULTS

Three main themes. "Driving reasons to return to sport" included the athletic identity, the competitive team spirit and commitment; "Preparation of body and mind" encompassed connectedness with health professionals, coaches, the sports team and family, graded exposure and progression of physical tasks, and psychological or cognitive skills to improve mental toughness; "Risk Acceptance" entailed situational risk analysis, problem solving, and avoidance of unacceptable risk and acceptance of risk and responsibility.

CONCLUSION

Participants described intrinsic and extrinsic motivators as drivers for rehabilitation. Interactions with therapists, coaches and team members enhanced confidence, supported by both physical rehabilitation and psychological influences. Psychological strategies were essential for several participants to return to sport. Graded sports exposure, leading towards total immersion in training and competition, appears important to manage re-injury fear following ACLR.

Weight Gain After ACL Reconstruction in Pediatric and Adolescent Patients

BACKGROUND

Adolescent athletes who sustain an anterior cruciate ligament (ACL) tear have significantly reduced activity levels during recovery. Activity level is linked to body mass index (BMI); however, it is unclear how recovery from an ACL reconstruction (ACLR) affects relative BMI and whether these changes persist after return to activity.

HYPOTHESIS

Patients' BMI percentile will significantly increase after ACLR, but will trend toward baseline after return to activity.

STUDY DESIGN

Cross-sectional study.

LEVEL OF EVIDENCE

Level 3.

METHODS

A retrospective review of 666 pediatric and adolescent patients who underwent ACLR was performed. Body mass was assessed by evaluating change in BMI percentile at 8 standard-of-care time windows relative to BMI percentile at time of surgery. Linear regression and bivariate and multivariate analyses were used to assess the effect of time window and other demographic factors on the change in BMI percentile. These analyses were rerun after dividing patients by clinical obesity categorization (underweight, normal, overweight, or obese) at time of surgery to assess the effect of preinjury body mass levels.

RESULTS

BMI percentile of all BMI categories tended to increase postoperatively, peaking 6 to 9 months after surgery, with a median increase of 1.83 percentile points. After this peak, BMI approached baseline but remained elevated at 0.95 percentile points 2 years postoperatively. Beginning 3 months after surgery, the normal-weight group had significantly larger changes in BMI percentile at each time window, peaking at 4.15 points above baseline at 9 months. This BMI increase among normal-weight patients persisted in the second postoperative year, with a median percentile increase of 2.63 points.

CONCLUSION

Pediatric and adolescent patients, especially those with a normal BMI, undergo significant changes to their BMI during recovery from ACLR.

CLINICAL RELEVANCE

Patients' failure to return to their presurgical BMI percentile 2 years postoperatively suggests that ACLR may have long-reaching and often unappreciated effects on body mass.

The effects of pediatric obesity on patellofemoral joint contact force during walking

BACKGROUND

Obesity increases a child's risk of developing knee pain across the lifespan, potentially through elevated patellofemoral joint loads that occur during habitual weight-bearing activities.

RESEARCH QUESTION

Do obese children have greater absolute and patellar-area-normalized patellofemoral joint forces compared to healthy weight children during walking?

METHODS

We utilized a cross-sectional design to address the aims of this study. Experimental biomechanics data were collected during treadmill walking in 10 healthy-weight and 10 obese 8-12 year-olds. We used radiographic images to develop subject-specific musculoskeletal models, generated walking simulations from the experimental data, and predicted patellofemoral joint contact force using established techniques.

RESULTS

We found that the obese children had 1.98 times greater absolute (p = 0.002) and 1.81 times greater patellar-area-normalized (p = 0.008) patellofemoral joint contact forces compared to the healthy-weight children. We observed a stronger relationship between absolute patellofemoral joint contact force and BMI (r²=0.58) than between patellofemoral joint contact force and body fat percentage (r²=0.38).

SIGNIFICANCE

Our results indicate that obese children walk with increased patellofemoral loads in absolute terms and also relative to the area of the articulating surfaces, which likely contributes to the increased risk of knee pain in this pediatric population. This information, which provides a baseline comparison for future longitudinal studies, also informs the type and frequency of physical activity prescription aimed at reducing the risk of knee injury and improving long-term outcomes.

Establishing outcome measures in early knee osteoarthritis

The classification and monitoring of individuals with early knee osteoarthritis (OA) are important considerations for the design and evaluation of therapeutic interventions and require the identification of appropriate outcome measures. Potential outcome domains to assess for early OA include patient-reported outcomes (such as pain, function and quality of life), features of clinical examination (such as joint line tenderness and crepitus), objective measures of physical function, levels of physical activity, features of imaging modalities (such as of magnetic resonance imaging) and biochemical markers in body fluid. Patient characteristics such as adiposity and biomechanics of the knee could also have relevance to the assessment of early OA. Importantly, research is needed to enable the selection of outcome measures that are feasible, reliable and validated in individuals at risk of knee OA or with early knee OA. In this Perspectives article, potential outcome measures for early symptomatic knee OA are discussed, including those measures that could be of use in clinical practice and/or the research setting.

Patellofemoral pain, body morphology and alignment in female pubertal dancers: One-year follow-up

The aim of this study was to assess changes in body morphology, anatomical alignment and prevalence of patellofemoral pain (PFP) in young female dancers along one year of pubertal growth, and to identify the risk factors related to PFP in these young dancers. Both legs of 60 dancers were evaluated during grade 7 and again after 1-year. At each of these points in time, the dancers were interviewed concerning their background, and anthropometric measurements, lower-limb physical examinations and knee ultrasound scans were performed. Morphological parameters changed significantly from baseline to follow-up. PFP was found in 53.3% of the dancers' knees at baseline. At follow-up, 55.4% of the asymptomatic knees at baseline developed PFP, and only 9.4% of the symptomatic knees at baseline recovered. Lower BMI was identified among dancers who developed PFP during follow-up compared with dancers with no PFP, either at baseline or at follow-up. A positive grinding and positive Patellar Inhibition Test (PIT) were found to be risk factors for PFP at follow-up. A high prevalence of young dancers suffered PFP, from injuries they sustained mostly during the 1-year of dance practice. Parameters predisposing the dancers to PFP should be identified at early stages of dance class.

A pragmatic approach to prevent post-traumatic osteoarthritis after sport or exercise-related joint injury

Lower extremity musculoskeletal injuries are common in sport and exercise, and associated with increased risk of obesity and post-traumatic osteoarthritis (PTOA). Unlike other forms of osteoarthritis, PTOA is common at a younger age and associated with more rapid progression, which may impact career choices, long-term general health and reduce quality of life. Individuals who suffer an activity-related joint injury and present with abnormal joint morphology, elevated adiposity, weak musculature, or become physically inactive are at increased risk of PTOA. Insufficient exercise therapy or incomplete rehabilitation, premature return-to-sport and re-injury, unrealistic expectations, or poor nutrition may further elevate this risk. Delay in surgical interventions in lieu of exercise therapy to optimize muscle strength and neuromuscular control while addressing fear of movement to guarantee resumption of physical activity, completeness of rehabilitation before return-to-sport, education that promotes realistic expectations and self-management, and nutritional counseling are the best approaches for delaying or preventing PTOA.

Age-Dependent Patellofemoral Pain: Hip and Knee Risk Landing Profiles in Prepubescent and Postpubescent Female Athletes

BACKGROUND

Female athletes are at an increased risk of developing patellofemoral pain (PFP) relative to male athletes. The unique effects of maturation may compound that risk. Hypothesis/Purpose: The purpose was to evaluate the neuromuscular control mechanisms that are adaptive to pubertal maturation and determine their relative contribution to PFP development. It was hypothesized that aberrant landing mechanics (reduced sagittal-plane and increased frontal- and transverse-plane kinematics and kinetics) would be associated with an increased risk for PFP.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

There were 506 high school female athletes who completed a detailed medical history, the Anterior Knee Pain Scale, and a knee examination for the diagnosis of PFP and attended follow-up appointments. Athletes performed a drop vertical jump task instrumented with force plates, and biomechanical measures generated from standard 3-dimensional biomechanical analyses were used to classify participants into high- or low-risk knee and hip landing profiles for the development of PFP. The biomechanical measures used in the knee landing profile included sagittal-plane knee range of motion, peak knee abduction angle, peak knee abduction moment, and peak-to-peak transverse-plane knee moment. The biomechanical measures used in the hip landing profile included sagittal-plane hip range of motion, peak hip extensor moment, peak abductor moment, and peak hip rotator moment. Testing was conducted at sport-specific preseason appointments over the course of 2 years, and changes in pubertal status, landing profile, and PFP development were documented.

RESULTS

Female athletes with high-risk hip landing profiles experienced increased hip flexion and decreased abductor, rotator, and extensor moments. Participants with high-risk hip landing profiles who transitioned to postpubertal status at follow-up had higher odds (odds ratio, 2.1 [95% CI, 1.1-4.0]; P = .02) of moving to a low-risk hip landing profile compared with those who had not reached postpubertal status at follow-up. Participants with high-risk knee landing profiles experienced decreased knee flexion and increased knee abduction, external abductor, and external rotator moments. Pubertal maturation was not associated with a change in the high-risk knee landing profile at follow-up.

CONCLUSION

The progression from prepubertal to postpubertal status may have a protective effect on high-risk hip mechanics but no similar adaptations in high-risk knee mechanics during maturation. These data indicate that before puberty, maladaptive hip mechanics may contribute to PFP, while aberrant knee mechanics associated with PFP are sustained throughout the maturational process in young female athletes.

Risk factors associated with self-reported injury history in female youth soccer players

BACKGROUND

studies that investigate risk factors for musculoskeletal injuries in female youth athletes are limited, especially related to training attributes and position status.

OBJECTIVE

to determine risk factors including training attributes and position status for a self-reported musculoskeletal injury history in female youth soccer players.

METHODS

we conducted a cross-sectional study of young female soccer players (mean age: 13.6 ± 2.3 years). we asked about their history of musculoskeletal injuries using an electronic questionnaire. the proportion of young female soccer players with and without a history of soccer-related musculoskeletal injuries were compared based on physical characteristics, training attributes, position status (single vs. multiple), lower extremity strength, and joint laxity. a binary logistic regression analysis was used to generate, and adjusted odds ratios adjusted for potential co-variates (aor). a 95% confidence interval (95%ci) that did not cross one or p < 0.05 were considered statistically significant.

RESULTS

a total of 160 young female soccer players (mean age: 13.6 ± 2.3 years) participated in the study. an independent association was found between prior musculoskeletal injuries and older ages (aor: 1.60, 95%ci: 1.17, 2.20, p = 0.004), higher weight (aor: 1.10, 95%ci: 1.01, 1.20, p = 0.026), and greater bmi (aor: 1.43, 95%ci: 1.07, 1.90, p = 0.014).

CONCLUSIONS

musculoskeletal injuries were associated with age, weight, and bmi in female youth players. the current study indicates that maintaining proper body composition may be beneficial to reduce musculoskeletal injuries among female youth soccer players.

Weak associations between body mass index and self-reported disability in people with unilateral anterior cruciate ligament reconstruction

PURPOSE AND HYPOTHESIS

Individuals with an anterior cruciate ligament reconstruction (ACLR) are susceptible to persistent disability, weight gain and the development of knee osteoarthritis. It remains unclear whether body mass index (BMI) is a factor that influences disability following ACLR. The purpose of this study was to determine the association between BMI and self-reported disability [International Knee Documentation Committee (IKDC) Index] in individuals with a unilateral ACLR. We hypothesized that lower BMI would associate with higher IKDC.

METHODS

BMI and IKDC were measured in 668 individuals with a unilateral ACLR (60.9% female, BMI 24.4 ± 3.7 kg/m², IKDC 84.7 ± 11.9%). Bivariate associations were conducted between BMI and IKDC for the entire sample and selected subsets (gender, ACLR graft type and history of meniscal injury). Multiple regression analyses were used to determine the impact of potential covariates (Tegner score, age and months since ACLR) for significant bivariate associations. After accounting for covariates, there were no significant associations between BMI and IKDC when separately evaluating the cohort based on either gender or history of a concomitant meniscal injury. The odds of achieving age- and gender-matched healthy population average IKDC scores for those with low (<25) and high (≥25) BMI were determined.

RESULTS

Lower BMI associated with higher IKDC (r = -0.08, P = 0.04). For the entire sample, BMI did not uniquely predict variance in IKDC (ΔR ² > 0.001, n.s.) after accounting for covariates. BMI uniquely predicted a significant but negligible amount of variance in IKDC in individuals with a patellar tendon autograft (ΔR ² = 0.015, n.s.). Individuals with low BMI demonstrated higher odds (odds ratio = 1.45; 1.05-1.99) of achieving population average IKDC scores compared to participants with high BMI.

CONCLUSIONS

There was a significant but negligible correlation between lower BMI and lesser disability in individuals with unilateral ACLR and individuals who are underweight or of normal BMI demonstrated higher odds of achieving population average IKDC scores compared to overweight or obese individuals. While an overall association was found between lower BMI and lesser disability, the magnitude of the association remains negligible; therefore, BMI was not a strong clinical predictor of successful ACLR outcomes in this cohort of patients with unilateral ACLR.

LEVEL OF EVIDENCE

Cross-sectional prognostic study, Level II.

'What's my risk of sustaining an ACL injury while playing football (soccer)?' A systematic review with meta-analysis

OBJECTIVE

To estimate the incidence proportion (IP) and incidence rate (IR) of ACL injury in football players.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

PubMed, CINAHL and SPORTDiscus electronic databases were searched from inception to 20 January 2017.

ELIGIBILITY CRITERIA FOR SELECTING STUDY

Studies that reported the total number of participants/population by sex, total number of ACL injuries by sex and total person-time by sex were included.

RESULTS

Twenty-eight studies were included. The IP and IR of ACL injury in female football players were 2.0% (95% CI 1.2% to 3.1%) and 2.0/10 000 athlete exposures (AEs) (95% CI 1.6 to 2.6; I²=91%) over a period of one season to 4 years. The IP and IR of ACL injury in male players were 3.5% (95% CI 0.7% to 8.2%) and 0.9/10 000 AEs (95% CI 0.7 to 1.1; I²=94%). Studies that evaluated matched cohorts of female and male players showed no difference in IP (relative risk=1.2; 95% CI 0.9 to 1.6; P=0.47) over a period of one season to 4 years. Women were at greater risk than men (incidence rate ratio (IRR)=2.2; 95% CI 1.6 to 3.1; I²=83%; P<0.001). When accounting for participation level, the difference in IR between women and men was greatest for intermediate players (IRR=2.9; 95% CI 2.4 to 3.6) compared with amateur (IRR=2.6; 95% CI 1.4 to 4.8) and elite (IRR=2.0; 95% CI 1.1 to 3.4) players.

SUMMARY/CONCLUSION

Overall, more men sustained ACL injury in football. There was no difference in the relative risk of ACL injury between female and male football players in a window that spanned one season to 4 years. The IR of ACL injury among women was 2.2 times higher than the IR of ACL injury among men. The reported sex disparity in ACL injury was independent of participation level.

Ultrasonography and clinical examination of knee injuries in pre- and post- menarche dancers

This study aimed at evaluating whether the prevalence of knee injuries and morphological features are different among pre-and-post menarche dancers; Sixty-seven pre-and-post menarche dancers were screened for anthropometric parameters; knee laxity; patella femoral pain syndrome (PFPS), pathologies and anatomical structure of the knees. Both groups showed a high and similar prevalence of PFPS. The post-menarche dancers produced a significantly higher rate of Tanner stages 3-4 (p = .010), greater weight (p < .001) higher BMI (p = .003); and, higher prevalence of MCL pathology, pes planus, and scoliosis compared with pre-menarche dancers (p < .05). The pre-menarche dancers started dance practice earlier (p = .008); and, showed significantly higher prevalence of lateral laxity, patellar laxity, positive Lachman test and positive Drawer test compared with post-menarche dancers (p < .05). Interactions (menarche yes/no by PFPS no/one leg/both legs) were found for BMI (p = .044; η² = .187), trochlear cartilage thickness (p = .020; η² = 0.121) and tip of patella - trochlear groove distance (p = .024; η² = .150). Pre-and-post-menarche female dancers demonstrated similar prevalence of knee injuries, with different body morphology.

Prevalence of adolescent physical activity-related injuries in sports, leisure time, and school: the National Physical Activity Behaviour Study for children and Adolescents

BACKGROUND

The purpose of this study was to investigate the prevalence of adolescent physical activity-related injuries in sports club activities, leisure time physical activity and school-based physical activity. The secondary aim was to investigate the differences in the prevalence of physical activity -related injuries between years 2014 and 2016. In addition, we set out to study the associations between age, sex and the frequency of physical activity and injury prevalence.

METHODS

This cross-sectional study is based on the National Physical Activity Behaviour Study for Children and Adolescents (LIITU in Finnish) conducted in years 2014 and 2016. The subjects completed an online questionnaire in the classroom during school hours. A total of 8406 subjects participated in the current study. Out of these, 49% were boys and 51% were girls. The proportions of 11-, 13-, and 15-year-olds were 35%, 34% and 31%, respectively.

RESULTS

In the combined data for 2014 and 2016, injury prevalence was higher in sports club activities (46%, 95% CI 44.8-47.8) than in leisure time PA (30%, 95% CI, 28.5-30.5) or school-based PA (18%, 95% CI, 17.4-19.1). In leisure time PA, the injury prevalence was higher than in school-based PA. In all the three settings, injury prevalence was higher in 2016 than in 2014. Frequency of PA was associated with a higher risk for PA-related injuries in sports clubs and leisure time.

CONCLUSIONS

With half of the subjects reporting at least one PA-related injury during the past year, results indicate that adolescent PA-related injuries are a large-scale problem. There is a worrisome rise in injury prevalence in recent years. From a public health standpoint, there is an urgent need to invest in injury prevention to reverse this trend.

Higher Fat Mass Is Associated With a History of Knee Injury in Youth Sport

Study Design Historical cohort study. Background History of a knee joint injury and increased fat mass are risk factors for joint disease. Objective The objective of this study was to examine differences in adiposity, physical activity, and cardiorespiratory fitness between youths with a 3- to 10-year history of sport-related intra-articular knee injury and uninjured controls. Methods One hundred young adults (aged 15-26 years; 55% female) with a sport-related intra-articular knee injury sustained 3 to 10 years previously and 100 controls matched for age, sex, and sport, who had no history of intra-articular knee injury, were recruited. Fat mass index (FMI) and abdominal fat (fat mass at the L1 to L4 vertebral levels) were derived using dual-energy X-ray absorptiometry. Physical activity and cardiorespiratory fitness were measured using the Godin Leisure-Time Exercise Questionnaire and the multistage 20-meter shuttle run test for aerobic fitness, respectively. Results Previously injured participants demonstrated higher FMI (within-pair difference, 1.05 kg/m²; 95% confidence interval [CI]: 0.53, 1.57) and abdominal fat (461 g; 95% CI: 228, 694) than uninjured controls. In multivariable linear regression analysis, previous injury was significantly associated with increased FMI. This increase was attenuated in those who participated in higher levels of physical activity or had higher estimated maximum volume of oxygen. Conclusion As a risk factor for osteoarthritis in an already susceptible group, excess adiposity is an undesirable trait in the potential pathway to joint disease. Increasing physical activity in this population may be a potential intervention to reduce adiposity thus impede disease initiation and/or progression. Level of Evidence Level 2b. J Orthop Sports Phys Ther 2017;47(2):80-87. doi:10.2519/jospt.2017.7101.

"What Does Weight Have to Do with It?" Parent Perceptions of Weight and Pain in a Pediatric Chronic Pain Population

Tailored pain management strategies are urgently needed for youth with co-occurring chronic pain and obesity; however, prior to developing such strategies, we need to understand parent perspectives on weight in the context of pediatric chronic pain. Participants in this study included 233 parents of patients presenting to a multidisciplinary pediatric chronic pain clinic. Parents completed a brief survey prior to their child’s initial appointment; questions addressed parents’ perceptions of their child’s weight, and their perceptions of multiple aspects of the relationship between their child’s weight and chronic pain. The majority (64%) of parents of youth with obesity accurately rated their child’s weight; this group of parents was also more concerned (p < 0.05) about their child’s weight than parents of youth with a healthy weight. However, the majority of parents of youth with obesity did not think their child’s weight contributed to his/her pain, or that weight was relevant to their child’s pain or pain treatment. Overall, only half of all parents saw discussions of weight, nutrition, and physical activity as important to treating their child’s pain. Results support the need for addressing parents’ perceptions of their child’s weight status, and educating parents about the relationship between excessive weight and chronic pain.

Vertical stiffness is not related to anterior cruciate ligament elongation in professional rugby union players

Background

Novel research surrounding anterior cruciate ligament (ACL) injury is necessary because ACL injury rates have remained unchanged for several decades. An area of ACL risk mitigation which has not been well researched relates to vertical stiffness. The relationship between increased vertical stiffness and increased ground reaction force suggests that vertical stiffness may be related to ACL injury risk. However, given that increased dynamic knee joint stability has been shown to be associated with vertical stiffness, it is possible that modification of vertical stiffness could help to protect against injury. We aimed to determine whether vertical stiffness is related to measures known to load, or which represent loading of, the ACL.

Methods

This was a cross-sectional observational study of 11 professional Australian rugby players. Knee kinematics and ACL elongation were measured from a 4-dimensional model of a hopping task which simulated the change of direction manoeuvre typically observed when non-contact ACL injury occurs. The model was generated from a CT scan of the participant's knee registered frame by frame to fluoroscopy images of the hopping task. Vertical stiffness was calculated from force plate data.

Results

There was no association found between vertical stiffness and anterior tibial translation (ATT) or ACL elongation (r=−0.05; p=0.89, and r=−0.07; p=0.83, respectively). ATT was related to ACL elongation (r=0.93; p=0.0001).

Conclusions

Vertical stiffness was not associated with ACL loading in this cohort of elite rugby players but a novel method for measuring ACL elongation in vivo was found to have good construct validity.

Sex and growth effect on pediatric hip injuries presenting to sports medicine clinic

To compare sports-related hip injuries on the basis of sex and age in a cohort of young athletes. A 5% random probability sample of all new patients' charts over a 10-year time period was selected for investigation. The most common hip injury diagnoses, sport at time of injury, mechanism (acute/traumatic vs. overuse), and types (bony vs. soft tissue) were compared by sex and age (preadolescent vs. adolescent). Descriptive and χ-analyses were carried out. The interaction of sex and age with respect to hip injury over time was examined by two-way (sex, age) analysis of variance. A total of 2133 charts were reviewed; N=87 hip injuries. The main diagnoses for males included labral tear (23.1%), avulsion fracture (11.5%), slipped capital femoral epiphysis (11.5%), dislocation (7.7%), and tendonitis (7.7%). The main diagnoses for females were labral tear (59.0%), tendonitis (14.8%), snapping hip syndrome (6.6%), strain (4.9%), and bursitis (4.9%). The five most common sports/activities at the time of hip injury were dancing/ballet (23.0%), soccer (18.4%), gymnastics (9.2%), ice hockey (8.1%), and track and field (6.9%). Age by sex comparisons showed a greater proportion of the total hip injuries (38.5%) in males compared with females (8.2%) during preadolescence (5-12 years). However, in adolescence (13-17 years), the hip injury proportion was significantly higher in females (91.8%) compared with males (61.5%; P<0.001). Injury mechanism and type differed by sex, with females sustaining more chronic/overuse (95.1%) and soft tissue type injuries (93.4%) compared with males (50.0 and 53.8%, respectively; P<0.001). Females were found to have a sharper increase in hip injury proportion as they progressed through puberty compared with males (analysis of variance sex-by-age interaction; P<0.001). Hip injury mechanism and type differed significantly between males and females during growth. Notably, the proportion of hip injuries in the young female athletes showed a significantly greater increase with advancing age compared with males. Hip injuries in children and the interplay with growth, as it relates to injury predisposition, require further investigation to facilitate efforts aimed at prevention.

LEVEL OF EVIDENCE III

Cross-sectional epidemiological study.

Is Knee Pain During Adolescence a Self-limiting Condition? Prognosis of Patellofemoral Pain and Other Types of Knee Pain

BACKGROUND

The prevalence of adolescent knee pain is 33%, and patellofemoral pain (PFP) is the most common diagnosis with a nontraumatic onset. The 2-year prognosis of adolescent PFP compared with other types of knee pain is unknown.

PURPOSE

To investigate the 2-year prognosis of knee pain among adolescents with and without a diagnosis of PFP.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

In 2011, a cohort of 2200 adolescents aged 15 to 19 years answered an online questionnaire on musculoskeletal pain. Of these, 504 reported knee pain, and 153 of these were clinically diagnosed with PFP. After 2 years, the 504 adolescents, as well as 252 randomly selected adolescents who did not report knee pain in 2011, were contacted again. Primary outcome at follow-up was the proportion of adolescents with knee pain during the last week prior to follow-up.

RESULTS

Overall, 55.9% (95% CI, 50.8%-60.9%) of those reporting knee pain at baseline also reported pain 2 years later. Adolescents diagnosed with PFP had a 1.26 (95% CI, 1.05-1.50) higher relative risk (RR) of knee pain at follow-up compared with other types of knee pain. Adolescents with PFP were significantly more likely to reduce or stop sports participation compared with adolescents with other types of knee pain. Of those without knee pain at baseline, 12.8% (95% CI, 8.4%-17.2%) reported knee pain at follow-up in 2013. Adolescents with knee pain at baseline had a 4.51 (95% CI, 3.15-6.45) higher RR of knee pain at follow-up compared with adolescents without knee pain at baseline.

CONCLUSION

Knee pain during adolescence, and PFP in particular, is in most cases present after 2 years and thus may not be self-limiting. A greater focus on early detection and prevention of knee pain during adolescence is needed.

Analysis of patient-reported anterior knee pain scale: implications for scale development in children and adolescents

PURPOSE

The purpose of this investigation was to estimate and document the reliability and validity of the Anterior Knee Pain Scale (AKPS) and to estimate its relative prediction accuracy of anterior knee pain in young females.

METHODS

Data from a prospective, epidemiologic study to diagnose patellofemoral knee pain among female athletes (n = 499) using the Anterior Knee Pain Scale (AKPS). Data were treated in 4 phases (descriptive phase, reliability phase, scale refinement phase) and a final validation stage that was focused on an effort to test and document the validation of the AKPS short form and perform head-to-head comparisons of the 6-item short form with the original, 13-item form.

RESULTS

The AKPS was reduced from 13 items (αCoeff = 0.77, σSEM = 0.004) to 6 items (αCoeff = 0.78, σSEM = 0.004). Point-biserial correlations with patellofemoral pain diagnosis were comparable: r [498] = 0.70 (R(2) = 0.49, short form) and r [498] = 0.71 (R(2) = 0.51, long form), as was sensitivity: 84% (short form) and 80% (long form), and specificity: 89% (short form) and 90% (long form; AUC = 0.94 both).

CONCLUSION

The current analyses indicate that a subset of measures from the AKPS is responsive to patellofemoral pain symptoms and may support screening for related diagnoses. A simpler and quicker scale optimized for diagnostic accuracy could reduce the demand on patients, clinicians and research teams focused on the identification and management of patellofemoral pain.

LEVEL OF EVIDENCE

III.

Sports Specialization, Part II: Alternative Solutions to Early Sport Specialization in Youth Athletes

Context:

Many coaches, parents, and children believe that the best way to develop elite athletes is for them to participate in only 1 sport from an early age and to play it year-round. However, emerging evidence to the contrary indicates that efforts to specialize in 1 sport may reduce opportunities for all children to participate in a diverse year-round sports season and can lead to lost development of lifetime sports skills. Early sports specialization may also reduce motor skill development and ongoing participation in games and sports as a lifestyle choice. The purpose of this review is to employ the current literature to provide evidence-based alternative strategies that may help to optimize opportunities for all aspiring young athletes to maximize their health, fitness, and sports performance.

Evidence Acquisition:

Nonsystematic review with critical appraisal of existing literature.

Study Design:

Clinical review.

Level of Evidence:

Level 4.

Conclusion:

Based on the current evidence, parents and educators should help provide opportunities for free unstructured play to improve motor skill development and youth should be encouraged to participate in a variety of sports during their growing years to influence the development of diverse motor skills. For those children who do choose to specialize in a single sport, periods of intense training and specialized sport activities should be closely monitored for indicators of burnout, overuse injury, or potential decrements in performance due to overtraining. Last, the evidence indicates that all youth should be involved in periodized strength and conditioning (eg, integrative neuromuscular training) to help them prepare for the demands of competitive sport participation, and youth who specialize in a single sport should plan periods of isolated and focused integrative neuromuscular training to enhance diverse motor skill development and reduce injury risk factors.

Strength of Recommendation Taxonomy (SORT):

B.

Long-term athletic development, part 2: barriers to success and potential solutions

The first installment of this two-part commentary reviewed existing models of long-term athletic development. However, irrespective of the model that is adopted by practitioners, existing structures within competitive youth sports in addition to the prevalence of physical inactivity in a growing number of modern-day youth may serve as potential barriers to the success of any developmental pathway. The second part of this commentary will initially highlight common issues that are likely to impede the success of long-term athletic development programs and then propose solutions that will address the negative impact of such issues.

High knee abduction moments are common risk factors for patellofemoral pain (PFP) and anterior cruciate ligament (ACL) injury in girls: is PFP itself a predictor for subsequent ACL injury?

BACKGROUND

Identifying risk factors for knee pain and anterior cruciate ligament (ACL) injury can be an important step in the injury prevention cycle.

OBJECTIVE

We evaluated two unique prospective cohorts with similar populations and methodologies to compare the incidence rates and risk factors associated with patellofemoral pain (PFP) and ACL injury.

METHODS

The 'PFP cohort' consisted of 240 middle and high school female athletes. They were evaluated by a physician and underwent anthropometric assessment, strength testing and three-dimensional landing biomechanical analyses prior to their basketball season. 145 of these athletes met inclusion for surveillance of incident (new) PFP by certified athletic trainers during their competitive season. The 'ACL cohort' included 205 high school female volleyball, soccer and basketball athletes who underwent the same anthropometric, strength and biomechanical assessment prior to their competitive season and were subsequently followed up for incidence of ACL injury. A one-way analysis of variance was used to evaluate potential group (incident PFP vs ACL injured) differences in anthropometrics, strength and landing biomechanics. Knee abduction moment (KAM) cut-scores that provided the maximal sensitivity and specificity for prediction of PFP or ACL injury risk were also compared between the cohorts.

RESULTS

KAM during landing above 15.4 Nm was associated with a 6.8% risk to develop PFP compared to a 2.9% risk if below the PFP risk threshold in our sample. Likewise, a KAM above 25.3 Nm was associated with a 6.8% risk for subsequent ACL injury compared to a 0.4% risk if below the established ACL risk threshold. The ACL-injured athletes initiated landing with a greater knee abduction angle and a reduced hamstrings-to-quadriceps strength ratio relative to the incident PFP group. Also, when comparing across cohorts, the athletes who suffered ACL injury also had lower hamstring/quadriceps ratio than the players in the PFP sample (p<0.05).

CONCLUSIONS

In adolescent girls aged 13.3 years, >15 Nm of knee abduction load during landing is associated with greater likelihood of developing PFP. Also, in girls aged 16.1 years who land with >25 Nm of knee abduction load during landing are at increased risk for both PFP and ACL injury.

Do exercises used in injury prevention programmes modify cutting task biomechanics? A systematic review with meta-analysis

OBJECTIVE

Some injury prevention programmes aim to reduce the risk of ACL rupture. Although the most common athletic task leading to ACL rupture is cutting, there is currently no consensus on how injury prevention programmes influence cutting task biomechanics. To systematically review and synthesise the scientific literature regarding the influence of injury prevention programme exercises on cutting task biomechanics.

DESIGN

The three largest databases (Medline, EMBASE and CINAHL) were searched for studies that investigated the effect of injury prevention programmes on cutting task biomechanics. When possible meta-analyses were performed.

RESULTS

Seven studies met the inclusion criteria. Across all studies, a total of 100 participants received exercises that are part of ACL injury prevention programmes and 76 participants served in control groups. Most studies evaluated variables associated with the quadriceps dominance theory. The meta-analysis revealed decreased lateral hamstrings electromyography activity (p ≤ 0.05) while single studies revealed decreased quadriceps and increased medial hamstrings activity and decreased peak knee flexion moment. Findings from single studies reported that ACL injury prevention exercises reduce neuromuscular deficits (knee valgus moment, lateral trunk leaning) associated with the ligament and trunk dominance theories, respectively. The programmes we analysed appear most effective when they emphasise individualised biomechanical technique correction and target postpubertal women.

CONCLUSIONS

The exercises used in injury prevention programmes have the potential to improve cutting task biomechanics by ameliorating neuromuscular deficits linked to ACL rupture, especially when they emphasise individualised biomechanical technique correction and target postpubertal female athletes.

Does body mass index affect outcomes of ambulatory knee and shoulder surgery?

PURPOSE

Obesity is highly prevalent among patients with knee and shoulder injuries and is associated with greater odds of surgical treatment for these injuries. The purpose of this systematic review was to summarize the literature that has examined the association between body mass index (BMI) and outcomes of ambulatory knee and shoulder surgery.

METHODS

A literature search of PubMed and Medline was conducted up to December 2013. Studies that examined the association between BMI and outcomes after ambulatory knee and shoulder surgery (arthroscopy, repairs, and reconstructions) were included. Outcomes included postoperative functional scores, clinical scores, and complications.

RESULTS

Eighteen studies were included in this review; 13 involved knee surgery and 5 involved shoulder surgery. Seven knee studies and 2 shoulder studies found increased BMI to be associated with worse postoperative outcomes, whereas the remaining 9 studies did not find an association. Increased BMI was associated with worse clinical scores and less patient satisfaction after arthroscopic meniscectomy or debridement, and with worse clinical scores and lower activity levels after anterior cruciate ligament (ACL) reconstruction. It was also associated with worse clinical scores and a longer hospital stay after rotator cuff repair and with longer time to return to work after subacromial decompression. Six studies examined the association between BMI and complications, but all reported null findings.

CONCLUSIONS

There is a lack of consensus in the literature regarding the association between BMI and ambulatory knee and shoulder surgery. Several factors may have contributed to contradictory findings, including variation in measuring and classifying anthropometry, postoperative outcomes, and follow-up time.

LEVEL OF EVIDENCE

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