bluuebunny/crossref_metadata_2025_split huggingface dataset:
SPORT SPECIALIZATION AND COLLEGE SCHOLARSHIP BELIEFS AND FINANCIAL INVESTMENT AMONG HIGH SCHOOL BASEBALL PARENTS
Authors: Post Eric G. , Rosenthal Michael D. , Rauh Mitchell J. 
Published: April 2020

BACKGROUND: Youth athletes are increasingly encouraged to specialize in a single sport and participate on club teams year-round to be offered a college scholarship. For collegiate baseball, only 11.7 scholarships are available for a 35-player team. Presently, the beliefs of parents of baseball athletes towards sport specialization are unknown along with whether they have an accurate understanding of college baseball scholarship availability. PURPOSE: To describe the beliefs of parents of high school baseball players regarding sport specialization and college scholarships. A secondary purpose was to compare child baseball participation characteristics by parent median household income (MHI) categories. METHODS: During the 2019 spring baseball season, 155 parents (female N=82 (52.9%), age: 49.45.5 years) of high school baseball players from six San Diego county high schools completed an anonymous questionnaire concerning parent and child demographics, child baseball participation information (e.g., club baseball team participation), money spent on their child’s baseball participation, sport specialization status, and parent beliefs regarding sport specialization and college scholarships. Sport specialization status was determined using a validated 3-point specialization scale. Parent MHI was estimated using residence zip code and categorized into MHI tertiles (low, middle, high). RESULTS: Seventy-three parents (47.7%) classified their children as highly specialized and 110 parents (71.0%) reported their child played club baseball in addition to their high school team. Parents reported spending a median of $3000 [$1500-6000] on their child’s baseball participation during the previous year. Only 44 parents (28.4%) reported being concerned about sport specialization. Most parents (69.9%) believed that specialization would increase their child’s chances of making a college team. Parents underestimated the number of college baseball scholarships available per team (median [IQR]: 5 [0-5]), but 55 parents (35.9%) believed it was “somewhat” or “very likely” their child would receive a college baseball scholarship. Compared to low MHI parents, high MHI parents were more likely to classify their child as highly specialized (65.8% vs. 31.7%, p=0.02), and have a child participating in club baseball (82.1% vs. 58.3%, p=0.02). CONCLUSIONS: Parents who reported a greater financial investment in their child’s baseball participation believed it would improve their child’s sport performance to play college baseball. Despite having a realistic understanding of the limited college scholarships available, parents were optimistic that their child would receive a baseball scholarship. The current year-round, highly specialized environment of youth sports in the United States may favor families with more financial resources.
INCREASED PREVALENCE OF JUVENILE OSTEOCHONDRITIS DISSECANS IN PATIENTS WITH JUVENILE IDIOPATHIC ARTHRITIS
Authors: Hinkle Andrew , Dickason Celeste Quitiquit , Jinguji Thomas , Shenoi Susan , Thapa Mahesh , Thapa Mahesh , Saper Michael G. , Bompadre Viviana , Schmale Gregory A. 
Published: April 2020

Background: Juvenile Idiopathic Arthritis (JIA) is an autoimmune disorder presenting with chronic arthritis with prevalence of 5-20/100,000. Juvenile osteochondritis dissecans (OCD) is an idiopathic disease of articular cartilage and subchondral bone, has onset at 10-16 years, often affects the knee and ankle with prevalence of 5-30/100,000. Hypothesis/Purpose: We hypothesize that OCD is more prevalent in JIA, and when diagnosed in JIA, OCD is advanced, often requiring surgery. Methods: This was a retrospective review of patients with JIA and OCD treated between January 2008 and March 2019 at one children’s hospital. We queried Department of Rheumatology records for JIA patients treated during this interval as well as Departments of Orthopedics and Radiology records for patients with OCD. Demographic information, classification of the stability of OCD lesions by review of magnetic resonance imaging, and clinical details of treatment were recorded. Results: 2,021 JIA patients were identified, 20 of whom (19 girls, 1 boy) had OCD of the knee and/or talus for a prevalence of 1/100 or 1000/100,000, or approximately 30-200x that of the general population. These 20 patients had a total of 28 OCD lesions: 43% (9 femur, 3 talus) were radiographically stable over time, 50% (10 femur, 2 patella, and 2 talus) were unstable at initial diagnosis, and 7% (femur) were initially stable but progressed to unstable lesions despite drilling. Eleven patients (55%) underwent surgery: 5 with stable femoral lesions for persistent symptoms despite prolonged non-operative treatment, and 6 for treatment of their unstable lesions (femur and patella). Of these 11 patients, 3 underwent two or more surgeries for OCDs, and 3 were treated with hemiepiphysiodesis for concomitant genu valgum. Conclusion: OCD lesions are 30-200x more prevalent in JIA compared to the general population. In JIA, OCD often presents at an advanced stage requiring surgery for stabilization. Patients with JIA may benefit by early screening, to potentially allow for treatment of an OCD lesion prior to the progression to instability.
ADOLESCENTS REPORT SLEEP QUALITY IMPAIRMENTS ACUTELY POST-CONCUSSION
Authors: Wilson Julie C. , Kirkwood Michael W. , Provance Aaron J. , Walker Gregory A. , Wilson Pamela E. , Howell David R. 
Published: April 2020

Background: Recently, the association between concussion and sleep has been explored. Few studies have used validated patient-reported outcome measures to examine how sleep quality differs between adolescents who have recently sustained a concussion compared to healthy adolescents. Hypothesis/Purpose: Our purpose was to evaluate the effect of acute concussion on sleep quality using the Pittsburgh Sleep Quality Index (PSQI). We hypothesized that adolescents with acute concussion symptoms would report worse sleep quality compared to healthy adolescent athletes undergoing a pre-participation evaluation. Methods: Patients seen for initial evaluation at a sports medicine clinic within 14 days of sustaining a concussion were matched with healthy control subjects undergoing a pre-participation evaluation based on age, sex and concussion history at a 3:1 control:concussion subject ratio. Controls with history of concussion were included if fully recovered at their evaluation. Both groups completed the PSQI and Post-Concussion Symptom Inventory (PCSI). Those with concussion reported sleep quality since their injury, while controls reported sleep quality over the past month. The primary outcome was global PSQI score, where higher scores indicate worse sleep quality. We compared sleep quality ratings between groups using independent samples t-test, and proportion of poor sleep ratings using Chi-square analysis. We then constructed a multivariable regression model to assess the effect of acute concussion on global PSQI scores while adjusting for sex, age and concussion history. Results: We evaluated 17 patients with concussion (mean 8±3 days post-injury) who were matched with 51 controls. Demographic variables did not differ significantly between concussion and control groups (Table 1). The concussion group reported higher PCSI symptom rating (Table 1), and worse overall sleep quality (Table 2). Specifically, the concussion group reported longer time to fall asleep, later morning awakening, longer sleep duration and longer time in bed, compared to controls. The concussion group was also less likely to rate their sleep as “very good” compared to controls (Table 2). After adjusting for the independent effect of sex, age, and concussion history, concussion was significantly associated with higher PSQI scores (β=2.01, 95% CI= 0.35, 3.68; p= 0.019). Conclusion: Adolescents assessed within 14 days of concussion reported worse overall sleep quality, longer sleep duration, and decreased sleep efficiency compared to healthy adolescents. These results, obtained utilizing a validated measure, highlight the negative impact of acute concussion on sleep quality and provide additional support that assessment of sleep characteristics is an important component of acute concussion management. [Table: see text][Table: see text]
PATIENT REPORTED OUTCOMES ARE ASSOCIATED WITH ISOMETRIC STRENGTH DEFICITS EARLY AFTER ACL RECONSTRUCTION IN ADOLESCENTS
Authors: Weaver Adam , Macmillan Lauren , Suprenant Danielle , Giampetruzzi Nicholas 
Published: April 2020

Background: Quadriceps Femoris (QF) strength has been identified to impact patient reported function following ACL reconstruction (ACLR) at time of return to sport. Patients with higher subjective reports of knee function displayed greater QF symmetry. To our knowledge the relationship between patient reported outcomes and strength measurements have not been studied during the rehabilitation process in adolescent patients post ACLR. Hypothesis/Purpose: The purpose of this study was to examine the relationship of International Knee Documentation Committee subjective form (IKDC) and the Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) scores to isometric QF strength at three months status post ACLR. Methods: A retrospective chart review was conducted on patients treated with ACLR between July 2017 and April 2019 at a single institution. Patients between 12 and 20 years of age that underwent ACLR and completed a three-month functional tests assessment were included in the study. Data was collected for IKDC and ACL-RSI scores, and isometric strength testing at 60° of knee flexion on the HUMAC isokinetic dynamometer (CSMI USA, Stoughton, MA). Pearson correlation was used to determine if there is an association between IKDC and isometric strength, and Spearman Correlation to determine if there is an association between ACL-RSI and isometric strength. Results: The cohort included 138 patients (68 females; 16.16±1.88) (97.31±16.12 post-op days) status post ACLR, with an average IKDC score of 69.73±13.19 and average ACL-RSI score of 60.08±24.19. Hamstring autografts were the most common reconstruction (n=80, 58%). The average QF peak torque was 71.30±28.98 ft-lbs and average isometric QF strength deficit was 31.07±23.85 percent. IKDC scores were positively associated with QF peak torque isometric strength (r=0.437, P=<.0001). ACL-RSI scores were also positively associated with peak torque QF isometric strength (r=0.284, P=.001) and negatively associated with QF strength deficit (r= -.279, P=<.002). Conclusion: IKDC and RSI were positively associated with QF isometric strength in adolescent patients three months status post ACLR. These finding suggest that QF strength impacts patients’ reported function and psychological readiness to return to sport at this time point. Possible impact on rehabilitation includes implementing strategies to progress QF strength from three months status post to time of return to sport.
MICROENVIRONMENTAL INFLUENCES ON ARTICULAR CHONDROCYTE DIFFERENTIATION
Authors: Chau Michael , Toth Ferenc , Bendre Ameya , Armstrong Alexandra , Macalena Jeffrey , Tompkins Marc , Clohisy Denis , Nilsson Ola , Carlson Cathy 
Published: April 2020

Background: Immature articular cartilage (a.k.a. articular epiphyseal cartilage complex, AECC), serves dual functions as an articulating layer and surface growth plate. The AECC originates from an uninterrupted cartilaginous template during embryogenesis, presumably stemming from the same pool of progenitors, but it is unclear how the articulating layer is maintained throughout life, while the surface growth plate undergoes endochondral ossification. Hypothesis: The function and fate of chondrocytes in the AECC are not predetermined in the embryo, but instead can be influenced during development by biochemical and/or biomechanical stimuli in the cellular microenvironment. Methods: Microenvironments of the articulating layer and surface growth plate were switched in an in vivo goat model. Twelve 3-week-old goats were used. Osteochondral autografts were harvested from medial and lateral condyles and trochlea of the distal femur. Subchondral bone was removed (Figures 1A and 1B). Grafts were inverted and press-fit into select sites, which were full (condyles) or low (trochlea) weightbearing (Figures 1C through 1E). Animals were allowed ambulation and range of motion as tolerated. Two goats each were euthanized at 1, 2, 3, 6, 12, and 24 weeks postoperatively. Distal femurs were harvested and grafts were analyzed with trichrome staining and in situ hybridization for Col10, Col2, and Prg4. Results: All animals survived surgery, ambulated within 24 hours, and none exhibited signs of surgical site infection. Macroscopically, grafts at the trochlea and lateral condyle maintained a more cartilaginous appearance than those at the medial condyle, but all eventually developed an osseous appearance. Histologically, there was healing over time, with early grafts often containing areas of hemorrhage and occasionally necrosis, followed by formation of granulation tissue and subjacent myelofibrosis, with eventual invasion and ossification. At later timepoints, there was better graft incorporation at the articular surface without replacement by fibrosis at the medial condyle (Figure 2). In situ hybridization demonstrated some Prg4 positive cells and a decrease in Col10 expression at the articular surface (Figure 3). Conclusions: The synovial microenvironment may play a protective role against endochondral ossification. Some incorporation of epiphyseal cartilage into articular cartilage occurred at sites subjected to both compressive and shear forces. Data suggest the existence of local cytokines and/or matrix effects on chondrocytes that stimulate different cell functions and fates. A limitation of this study is its observational nature. Further understanding of articular chondrocyte differentiation and identification of key biochemical and/or biomechanical stimuli hold therapeutic promise for articular cartilage regeneration, repair, and replacement. [Figure: see text][Figure: see text][Figure: see text]
INCREASED TIBIOFEMORAL ROTATION WITH INCREASING SEVERITY OF PATELLAR INSTABILITY
Authors: Lin Kenneth M. , James Evan W. , Schlichte Lindsay , Wang Grace , Green Daniel 
Published: April 2020

Background: Tibiofemoral rotation (TFR), specifically external tibial rotation, has been recently identified as a potential contributing factor to patellar instability. However, no previous studies have explored the clinical effects of differing degrees of TFR in relation to patellar instability. Purpose and Hypothesis: The purpose of this study is to investigate the relationship between severity of instability with degree of TFR. Our hypothesis is that fixed or obligatory dislocators (FOD) are more likely to have increased external TFR (tibial external rotation compared to femur) than standard patellar instability (SPI) patients requiring medial patellofemoral ligament (MPFL) reconstruction, who will have similar or slightly increased external TFR compared to normal controls. Methods: A retrospective study was performed with patients from 3 cohorts from April 2009 to February 2019: FOD, SPI, and controls with normal magnetic resonance imaging (MRI) of the knee. All FOD patients from the study time frame were analyzed, while controls and SPI patients were randomly selected. Patients were included for age under 18 years and diagnosis corresponding to one of the three cohorts, and excluded for outside institution MRI, and previous MPFL reconstruction or tibial tubercle osteotomy. TFR was measured on preoperative axial MRI using the posterior femoral and tibial condylar lines (Figure 1). Tibial tubercle to trochlear groove distance (TT-TG) was measured. Intraclass correlation coefficient (ICC) was calculated among 3 measurers. Statistical analysis using ANOVA and t-test was performed with significance set at α=0.05. Results: A total of 57 patients were included, 19 in each cohort. Average age was 13.2 years (range 10-17 years), with 31 females (54%). ICC for TT-TG and TFR were 0.90 and 0.72, respectively. TT-TG differed between the controls and SPI patients (both P<0.001), and controls and FOD patients (P<0.001), but not between SPI and FOD patients (P=0.12). TFR differed among the three groups: 8.4° (SD 16.7°) external TFR in FOD, 1.6° (SD 5.4°) external TFR in SPI, and 2.5° (SD 5.8°) internal TFR in controls (P=0.0089). FOD patients had significantly greater external tibial rotation than the SPI group (P=0.047). Conclusions: The degree of TFR is correlated with severity of patellar instability, with greater external tibial rotation seen in FOD than SPI patients, while TT-TG was not different. Further information on the relationship of TFR and patellar instability will not only improve understanding of pathogenesis and prognosis, but may also direct surgical treatment strategies in refractory or severe cases. [Figure: see text][Figure: see text]
SEX-SPECIFIC ENERGY ABSORPTION STRATEGIES DURING UNANTICIPATED SINGLE-LEG LANDINGS IN ADOLESCENTS: IMPLICATIONS FOR KNEE INJURIES
Authors: Romanchuk Nicholas J. , Bel Michael J. Del , Benoit Daniel L. 
Published: April 2020

Background: The vast majority of ACL injuries in adolescents occur during non-contact injuries, in particular single-leg landings. The magnitude of energy absorption about each joint during theses landings influences the internal and external forces acting on the joints of the lower extremity. Understanding the biomechanics of landing in adolescent male and female athletes may provide insight into these non-contact injury mechanisms. Hypothesis/Purpose: This study set out to identify sex-specific energy absorption strategies during single-leg landing and determine the relationship between joint strength and the observed strategies. To better represent real-world conditions, we developed a novel unanticipated drop-jump landing protocol for this population. Methods: Thirty-one healthy youth athletes completed unanticipated single-leg drop-jump landings on their dominant limb. Kinematics and lower-limb contributions to energy absorption were calculated over the landing phase for each jump. Independent t-tests as well as Mann-Whitney U tests determined the presence of statistical differences between sexes. Pearson and Spearman correlation coefficients determined the relationship between isometric joint strength and the observed kinematics and energy absorption. Results: Females participants absorbed a larger proportion of the landing forces at the ankle and smaller proportion at the hip compared to males. Females also reached larger peak negative joint power in their knee and ankle. Both hip extension and ankle plantar flexion strength were correlated with greater spine flexion and less pelvic flexion. Conclusion: Females adopted an energy absorption strategy which utilized distal joints to absorb a larger portion of the landing forces and tended to absorb the forces later relative to males. A greater reliance on the distal joints is related to reduced hip strength and may increase the risk for sustaining an ACL injury.
THE IMPACT OF RULE CHANGES AND LEGISLATION ON THE INCIDENCE OF CONCUSSION IN HIGH SCHOOL SOCCER
Authors: Nussbaum Eric D. , Bjornaraa Jaynie , Gatt Charles J. 
Published: April 2020

Background: There is much concern over the incidence of concussion in high school sports, with a growing focus on soccer, necessitating the need for legislation and formal rule changes for safety reasons. Objective: To note differences in concussive injury between boys and girls soccer and determine the change in reported concussion rates from 2011 vs. 2017 in order to study the impact of legislation and rule changes on the rates of concussion in high school soccer in the state of New Jersey. Design: Comparative Study Methods: Licensed athletic trainers working in the secondary school setting in the state of New Jersey voluntarily participated in an online survey on the incidence of concussion in boys and girls soccer. This de-identified data was compared with data collected from a similar survey conducted in 2011. Results: In 2017 there were 168 concussions occurred among 3255 male soccer athletes. Eight-five percent of concussions (145/168) occurred during games, with the remainder occurring in practice. Forty-five percent (76/168) occurred to varsity players with the majority occurring during games (84%). Fewer concussions were reported to junior varsity and freshman players.. In 2017, Incidence Rate (IR) for all male soccer athletes was calculated at 0.36 concussions per 1000 athletic exposures (AE). Injury Proportion (IP) was 5%. Clinical Incidence was 0.05 concussions per athlete. This represented a 38% increase in IR/1000 AE from 2011 to 2017, and a 39% increase in IP 2011 vs 2017 In 2017, a total of 2604 female soccer athletes, reported 195 concussions with the majority occurring during games (83%). Varsity athlete reported the higher number of concussions relative to junior varsity and freshman soccer athletes IR/1000 AE was 0.48 vs 0.43 in 2011 (12% increase), while IP was 7% vs 6% in 2011 (17% increase Females had a greater IR/1000 AE than males (.48 vs. .36). Clinical incidence was also greater for female soccer athletes than male soccer athletes (0.075 vs. 0.05). Conclusion: Despite legislation and rule changes, the incidence of concussion in both boys and girls high school soccer is increasing and particularly during games. Playing at the varsity level and game play has the highest association with injury and should be subject to greater scrutiny. Additionally, more concussions are occurring to female soccer athletes than male players. This information provides a snapshot of a significant problem that deserves greater attention. [Table: see text][Table: see text]