Patient-reported outcome measures as an outcome variable in sports medicine research.

Injury prevention and rehabilitation research often address variables that would be considered clinician-oriented outcomes, such as strength, range of motion, laxity, and return-to-sport. While clinician-oriented variables are helpful in describing the physiological recovery from injury, they neglect the patient perspective and aspects of patient-centered care. Variables that capture patient perspective are essential when considering the impact of injury and recovery on the lives of patients. The inclusion of patient-reported outcome measures (PROMs) as dependent variables in sports medicine research, including injury prevention and rehabilitation research, provides a unique perspective regarding the patient's perception of their health status, the effectiveness of treatments, and other information that the patient deems important to their care. Over the last 20 years, there has been a significant increase in the use of PROMs in sports medicine research. The growing body of work gives opportunity to reflect on what has been done and to provide some ideas of how to strengthen the evidence moving forward. This mini-review will discuss ideas for the inclusion of PROMs in sports medicine research, with a focus on critical factors, gaps, and future directions in this area of research. Important elements of research with PROMs, including instrument selection, administration, and interpretation, will be discussed and areas for improvement, consideration, and standardization will be provided.

Non-Time-Loss and Time-Loss Injuries in Secondary School Girls' Volleyball Athletes: A Report From the National Athletic Treatment, Injury, and Outcomes Network Surveillance Program.

CONTEXT: Volleyball is a popular sport with a risk of injury to the entire body. Insight into non-time-loss (NTL) and time-loss (TL) injuries is needed to inform seasonal injury trends that may lead to appropriate prevention and management strategies. This study provides a descriptive analysis of volleyball injuries among secondary school athletes. STUDY DESIGN: Descriptive epidemiology study. METHODS: Data were collected from 72 secondary schools, representing 135 team seasons of data from the National Athletic Treatment, Injury, and Outcomes Network Surveillance Program (2014-2015 to 2018-2019 academic years). Injury counts, injury rates (IR) per 1000 athlete exposures (AEs), and incidence rate ratios (IRR) were reported with 95% confidence intervals (CIs). RESULTS: In total, 529 injuries over 193,858 AEs for girls' volleyball were captured, producing an IR of 2.73/1000AEs (95% CI = 2.50-2.96). The overall IR was highest during the preseason compared with regular season (IRR = 1.31, 95% CI = 1.09-1.59). Overall IRs were higher in competition (IR: 3.56, 95% CI = 3.07-4.05) compared with practice (IR: 2.38, 95% CI = 2.12-2.64; IRR = 1.49, 95% CI = 1.25-1.79). Common body locations injured were ankle (n = 141, 26.7%; NTL: n = 56, 21.7%; TL: n = 85, 31.7%), knee (n = 61, 11.5%; NTL: n = 33, 12.8%, TL: n = 28, 10.5%), hand/wrist (n = 59, 11.2%; NTL: n = 32, 12.4%, TL: n = 27, 10.1%), and head/face (n = 62, 11.7%; NTL: n = 14, 5.4%; TL: n = 47, 17.5%). CONCLUSIONS: Volleyball IRs were highest in preseason and during competition. Most injuries affected the lower-extremity which is notable considering the high upper-extremity load in volleyball. Consideration of strategies to reduce injuries prior to the start of the formal sports season may be needed to help reduce the incidence of preseason injuries.

Training Load Capacity, Cumulative Risk, and Bone Stress Injuries: A Narrative Review of a Holistic Approach.

Bone stress injuries (BSIs) are a common orthopedic injury with short-term, and potentially long-term, effects. Training load capacity, influenced by risk factors, plays a critical role in the occurrence of BSIs. Many factors determine how one's body responds to repetitive loads that have the potential to increase the risk of a BSI. As a scientific community, we have identified numerous isolated BSI risk factors. However, we have not adequately analyzed the integrative, holistic, and cumulative nature of the risk factors, which is essential to determine an individual's specific capacity. In this narrative review, we advocate for a personalized approach to monitor training load so that individuals can optimize their health and performance. We define "cumulative risk profile" as a subjective clinical determination of the number of risk factors with thoughtful consideration of their interaction and propose that athletes have their own cumulative risk profile that influences their capacity to withstand specific training loads. In our narrative review, we outline BSI risk factors, discuss the relationship between BSIs and training load, highlight the importance of individualizing training load, and emphasize the use of a holistic assessment as a training load guide.

Risk Factors for Plantar Fasciitis in Physically Active Individuals: A Systematic Review and Meta-analysis.

CONTEXT: Plantar fasciitis (PF) is a common condition in active individuals. The lack of agreement on PF etiology makes treatment challenging and highlights the importance of understanding risk factors for preventive efforts. OBJECTIVE: The purpose of this systematic review and meta-analysis was to determine what factors may put physically active individuals at risk of developing PF. DATA SOURCES: CENTRAL, CINAHL, EMBASE, Gray Lit, LILACS, MEDLINE (PubMed), ProQuest, Scopus, SPORTDiscus, and Web of Science were searched through April 2018 and updated in April 2020. STUDY SELECTION: Studies were included if they were original research investigating PF risk factors, compared physically active individuals with and without PF, were written in English, and were accessible as full-length, peer-reviewed articles. STUDY DESIGN: Systematic review and meta-analysis. LEVEL OF EVIDENCE: Level 3, because of inconsistent definitions and blinding used in the included observational studies. DATA EXTRACTION: Data on sample characteristics, study design and duration, groups, PF diagnosis, and risk factors were extracted. The methodological quality of the studies was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology statement. When means and standard deviations of a particular risk factor were presented 2 or more times, that risk factor was included in the meta-analysis. RESULTS: Sixteen studies were included in the systematic review and 11 risk factors in the meta-analysis. Increased plantarflexion range of motion (weighted mean difference [MD] = 7.04°; 95% CI, 5.88-8.19; P < 0.001), body mass index (MD = 2.13 kg/m2; 95% CI, 1.40-2.86; P < 0.001; I2 = 0.00%), and body mass (MD = 4.52 kg; 95% CI, 0.55-8.49; P = 0.026) were risk factors for PF. CONCLUSION: Interventions focused on addressing a greater degree of plantarflexion range of motion, body mass index, and body mass and their load on the force-absorbing plantar surface structures may be a good starting point in the prevention and treatment of active individuals with PF.

Incidence of Shoulder Injury in Elite Wheelchair Athletes Differ Between Sports: A Critically Appraised Topic.

Clinical Scenario: Until recently, injury epidemiology data on elite Paralympic athletes were limited. Current data suggest high rates of shoulder injury in wheelchair athletes. Differences in shoulder injury rates between sports have not been reported in this population. Clinical Question: Is the incidence of shoulder injury in elite wheelchair athletes different between sports? Summary of Key Findings: Shoulder injury rates are high in elite wheelchair athletes, particularly in sports such as field events and fencing that require a stable base (eg, trunk, core control) from which to perform. Wheelchair racing requires repetitive motions that contribute to shoulder injuries, but rates are lower than field sports and fencing. Wheelchair curling and sledge hockey have low shoulder injury risk. Clinical Bottom Line: Shoulder injury rates vary based on sport in elite wheelchair athletes. In addition to incorporating shoulder complex specific rehabilitation for overuse shoulder injuries, clinicians should focus on core and trunk stabilization in elite wheelchair athletes competing in sports, such as field events and fencing. Strength of Recommendation: Grade C evidence exists that reports shoulder injury rates among elite wheelchair athletes differ based on sport participation.

Clinical Breathing Mechanics Differ Based on Test and Position.

CONTEXT: Altered diaphragm function is linked to decreased core stabilization, postural changes, and decreased function. Two clinical tests used to assess breathing are the Hi-lo and lateral rib expansion (LRE) tests. It is currently unknown how breathing classification based on these tests differ and how their results are affected by varying test positions. OBJECTIVE: To compare the results of breathing tests when conducted in varying test positions. DESIGN: Prospective cross-sectional study. SETTING: University laboratory. PARTICIPANTS: A total of 50 healthy adults (females 31 and males 29; age 29.3 [4.1] y; height 170.0 [10.4] cm; weight70.7 [15.1] kg). INTERVENTION(S): Hi-lo and LRE tests in supine, seated, standing, and half-kneeling body positions. All tests were recorded and later scored by a single examiner. A generalized estimating equations approach with breathing test and body position as factors was used for analysis. Pairwise comparison with Bonferroni correction was used to adjust for multiple tests. Statistical significance was set at P = .05, 2 tailed. MAIN OUTCOME MEASURES: Hi-lo and LRE tests were scored based on the presence or absence of abdominal excursion, LRE, and superior rib cage migration. Following scoring, results were classified as functional or dysfunctional based on observation of these criteria. RESULTS: A significant breathing test × test position interaction (P < .01) was noted, as well as main effects for test (P < .01) and test position (P < .01). All Hi-lo test positions identified significantly more dysfunctional breathers in positions of increased stability demand (P < .01), except between standing and half-kneeling positions (P = .52). In the LRE test, all positions were similar (P > .99) except for half-kneeling, which was significantly different from all other positions (P < .01). CONCLUSIONS: The Hi-lo test and LRE tests assess different breathing mechanics. Clinicians should use these tests in combination to gain a comprehensive understanding of a person's breathing pattern. The Hi-lo test should be administered in multiple testing positions.

The Functional Arm Scale for Throwers (FAST)-Part I: The Design and Development of an Upper Extremity Region-Specific and Population-Specific Patient-Reported Outcome Scale for Throwing Athletes.

BACKGROUND: Upper extremity (UE) region-specific, patient-reported outcome (PRO) scales assess injuries to the UE but do not account for the demands of overhead throwing athletes or measure patient-oriented domains of health-related quality of life (HRQOL). PURPOSE: To develop the Functional Arm Scale for Throwers (FAST), a UE region-specific and population-specific PRO scale that assesses multiple domains of disablement in throwing athletes with UE injuries. In stage I, a beta version of the scale was developed for subsequent factor identification, final item reduction, and construct validity analysis during stage II. STUDY DESIGN: Descriptive laboratory study. METHODS: Three-stage scale development was utilized: Stage I (item generation and initial item reduction) and stage II (factor analysis, final item reduction, and construct validity) are reported herein, and stage III (establishment of measurement properties [reliability and validity]) will be reported in a companion paper. In stage I, a beta version was developed, incorporating National Center for Medical Rehabilitation Research disablement domains and ensuring a blend of sport-related and non-sport-related items. An expert panel and focus group assessed importance and interpretability of each item. During stage II, the FAST was reduced, preserving variance characteristics and factor structure of the beta version and construct validity of the final FAST scale. RESULTS: During stage I, a 54-item beta version and a separate 9-item pitcher module were developed. During stage II, a 22-item FAST and 9-item pitcher module were finalized. The factor solution for FAST scale items included pain (n = 6), throwing (n = 10), activities of daily living (n = 5), psychological impact (n = 4), and advancement (n = 3). The 6-item pain subscale crossed factors. The remaining subscales and pitcher module are distinctive, correlated, and internally consistent and may be interpreted individually or combined. CONCLUSION: This article describes the development of the FAST, which assesses clinical outcomes and HRQOL of throwing athletes after UE injury. The FAST encompasses multiple domains of disability and demonstrates excellent construct validity. CLINICAL RELEVANCE: The FAST provides a single UE region-specific and population-specific PRO scale for high-demand throwers to facilitate measurement of impact of UE injuries on HRQOL and clinical outcomes while quantifying recovery for comparative effectiveness studies.

The Functional Arm Scale for Throwers (FAST)-Part II: Reliability and Validity of an Upper Extremity Region-Specific and Population-Specific Patient-Reported Outcome Scale for Throwing Athletes.

BACKGROUND: The Functional Arm Scale for Throwers (FAST) is an upper extremity (UE) region-specific and population-specific patient-reported outcome (PRO) scale developed to measure health-related quality of life in throwers with UE injuries. Stages I and II, described in a companion paper, of FAST development produced a 22-item scale and a 9-item pitcher module. Stage III of scale development, establishing reliability and validity of the FAST, is reported herein. PURPOSE: To describe stage III of scale development: reliability and validity of the FAST. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Data from throwing athletes collected over 5 studies were pooled to assess reliability and validity of the FAST. Reliability was estimated using FAST scores from 162 throwing athletes who were injured (n = 23) and uninjured (n = 139). Concurrent validity was estimated using FAST scores and Disabilities of the Arm, Shoulder, and Hand (DASH) and Kerlan-Jobe Orthopaedic Clinic (KJOC) scores from 106 healthy, uninjured throwing athletes. Known-groups validity was estimated using FAST scores from 557 throwing athletes who were injured (n = 142) and uninjured (n = 415). Reliability and validity were assessed using intraclass correlation coefficients (ICCs), and measurement error was assessed using standard error of measurement (SEM) and minimum detectable change (MDC). Receiver operating characteristic curves and sensitivity/specificity values were estimated for known-groups validity. Data from a separate group (n = 18) of postsurgical and nonoperative/conservative rehabilitation patients were analyzed to report responsiveness of the FAST. RESULTS: The FAST total, subscales, and pitcher module scores demonstrated excellent test-retest reliability (ICC, 0.91-0.98). The SEM95 and MDC95 for the FAST total score were 3.8 and 10.5 points, respectively. The SEM95 and MDC95 for the pitcher module score were 5.7 and 15.7 points, respectively. The FAST scores showed acceptable correlation with DASH (ICC, 0.49-0.82) and KJOC (ICC, 0.62-0.81) scores. The FAST total score classified 85.1% of players into the correct injury group. For predicting UE injury status, a FAST total cutoff score of 10.0 out of 100.0 was 91% sensitive and 75% specific, and a pitcher module score of 10.0 out of 100.0 was 87% sensitive and 78% specific. The FAST total score demonstrated responsiveness on several indices between intake and discharge time points. CONCLUSION: The FAST is a reliable, valid, and responsive UE region-specific and population-specific PRO scale for measuring patient-reported health care outcomes in throwing athletes with injury.

Effects of mouthguards on vertical dimension, muscle activation, and athlete preference: a prospective cross-sectional study.

Mandibular repositioning and subsequent neuromuscular signaling are proposed mechanisms of action for commercial mouthguards marketed for performance enhancement. A prospective cross-sectional study of 24 healthy adult weightlifters with normal occlusal relationships was designed to determine whether 2 self-fit performance mouthguards; a custom-fabricated, bilaterally balanced, dual-laminated mouthguard; and no mouthguard (control) differed in their effects on vertical dimension, muscle activation, and user preference during a 75% maximum power clean lift. Each subject was tested for each of the mouthguard categories: Power Balance POWERUP, Under Armour ArmourBite, custom, and no mouthguard. Interocclusal distance was measured at baseline and with each mouthguard. Mean and peak activity of the anterior temporalis, masseter, sternocleidomastoid, and cervical paraspinal muscles was measured during sitting and during a 75% maximum power clean lift. A mouthguard preference questionnaire was completed. Analyses were conducted to determine whether interocclusal distance differed among mouthguard type and to examine the effect of mouthguard type on mean and peak muscle activation during the clean lift. Interocclusal distance was affected by mouthguard type (P = 0.01). Mean and peak activity of the anterior temporalis and masseter muscles and mean activity of the sternocleidomastoid muscle differed among mouthguards (P < 0.05). Mouthguard type did not influence muscle activation of the cervical paraspinal muscle group. Overall, the Power Balance mouthguard produced more muscle activity. Participants preferred custom mouthguards nearly 2:1 over self-fit performance mouthguards (P = 0.05). Participants perceived that they were stronger and were less encumbered when using a custom mouthguard during submaximum power clean lifts.

Functional movement screen differences between male and female secondary school athletes.

The functional movement screen (FMS) is commonly used to assess movement capacity and determine injury risk. Evidence suggests that athletes who score 14 points or less on the FMS are at increased risk for injury, but differences between males and females have been minimally studied. The purpose of this study was to investigate sex differences in FMS scores of secondary school athletes. Using a cross-sectional study design, 60 healthy secondary school athletes performed the FMS, which is composed of 7 functional movement tasks (deep squat, hurdle step, inline lunge, shoulder mobility, active straight-leg raise, trunk stability push-up, and rotary stability) and 3 clearance screens. Dependent variables were FMS total composite score and individual task scores; secondary analyses were performed using total research score and individual task research scores when indicated. Lower scores indicated functional movement deficits and increased injury risk. Healthy secondary school female athletes scored lower on the total composite (p = 0.004) than healthy secondary school male athletes. Females also scored lower on the following individual FMS tasks: inline lunge (p < 0.04) and trunk stability push-up (p = 0.001). Healthy secondary school female athletes scored 14 or less on the FMS total composite score and significantly lower in general compared with healthy secondary school male athletes, which suggests these female athletes may be at higher risk for injury. Factors that may contribute to increased injury risk include deficits in mobility, core stabilization, and coordinated movement patterns. Clinicians should be aware of possible sex differences when using the FMS and developing injury prevention programs.

Hip and glenohumeral rotational range of motion in healthy professional baseball pitchers and position players.

BACKGROUND: Research suggests that limitations in the hip motion of baseball players may lead to altered motion at the glenohumeral joint to maintain throwing velocity, thereby predisposing the upper extremity to injury. PURPOSE: To measure and evaluate the correlation between hip and shoulder rotational range of motion (ROM) in healthy professional baseball players. STUDY DESIGN: Descriptive laboratory study. METHODS: Ninety-nine professional baseball players (50 pitchers and 49 position players; mean age ± standard deviation [SD], 22 ± 2.8 years; mean height ± SD, 187 ± 5.4 cm; mean weight ± SD, 81.6 ± 7.7 kg) with no history of hip or shoulder injury were tested. Dominant and nondominant hip and glenohumeral joints were measured for the following passive ROM variables: (1) hip internal rotation (IR), (2) hip external rotation (ER), (3) total hip rotational ROM (IR + ER), (4) isolated glenohumeral IR, (5) isolated glenohumeral ER, and (6) total glenohumeral rotational ROM (IR + ER). RESULTS: Statistically, hip ER and total hip rotational ROM were greater in position players than in pitchers and less in the lead leg compared with the stance leg hip with groups combined; however, differences are not clinically meaningful. Pitchers had more glenohumeral rotational ROM than did position players. For all players, glenohumeral motion had less IR and greater ER in the throwing arm than the nonthrowing arm, but total glenohumeral rotational ROM was equivalent between sides. The correlations between hip and glenohumeral ROM were little, if any, and ranged from r = -0.19 to 0.11 (P = .006-.94) for all players and r = -0.29 to 0.23 (P = .04-.97) for pitchers only. CONCLUSION: These data suggest no clinically meaningful differences in hip ROM between pitchers and position players and between lead leg and stance legs of all players. There is little or no relationship between hip and glenohumeral ROM in healthy professional baseball players. CLINICAL RELEVANCE: The study findings add to the growing body of evidence that suggests an absence of chronic hip ROM adaptations. It is therefore suggested that in the hip, unlike the glenohumeral joint, symmetry in ROM between player positions and dominant and nondominant sides should be expected in healthy professional baseball pitchers and position players.

The influence of training and mental skills preparation on injury incidence and performance in marathon runners.

There has been a considerable increase in the number of participants running marathons over the past several years. The 26.2-mile race requires physical and mental stamina to successfully complete it. However, studies have not investigated how running and mental skills preparation influence injury and performance. The purpose of our study was to describe the training and mental skills preparation of a typical group of runners as they began a marathon training program, assess the influence of training and mental skills preparation on injury incidence, and examine how training and mental skills preparation influence marathon performance. Healthy adults (N = 1,957) participating in an 18-week training program for a fall 2011 marathon were recruited for the study. One hundred twenty-five runners enrolled and received 4 surveys: pretraining, 6 weeks, 12 weeks, posttraining. The pretraining survey asked training and mental skills preparation questions. The 6- and 12-week surveys asked about injury incidence. The posttraining survey asked about injury incidence and marathon performance. Tempo runs during training preparation had a significant positive relationship to injury incidence in the 6-week survey (ρ[93] = 0.26, p = 0.01). The runners who reported incorporating tempo and interval runs, running more miles per week, and running more days per week in their training preparation ran significantly faster than did those reporting less tempo and interval runs, miles per week, and days per week (p ≤ 0.05). Mental skills preparation did not influence injury incidence or marathon performance. To prevent injury, and maximize performance, while marathon training, it is important that coaches and runners ensure that a solid foundation of running fitness and experience exists, followed by gradually building volume, and then strategically incorporating runs of various speeds and distances.

Core stability training for injury prevention.

CONTEXT: Enhancing core stability through exercise is common to musculoskeletal injury prevention programs. Definitive evidence demonstrating an association between core instability and injury is lacking; however, multifaceted prevention programs including core stabilization exercises appear to be effective at reducing lower extremity injury rates. EVIDENCE ACQUISITION: PUBMED WAS SEARCHED FOR EPIDEMIOLOGIC, BIOMECHANIC, AND CLINICAL STUDIES OF CORE STABILITY FOR INJURY PREVENTION (KEYWORDS: "core OR trunk" AND "training OR prevention OR exercise OR rehabilitation" AND "risk OR prevalence") published between January 1980 and October 2012. Articles with relevance to core stability risk factors, assessment, and training were reviewed. Relevant sources from articles were also retrieved and reviewed. RESULTS: Stabilizer, mobilizer, and load transfer core muscles assist in understanding injury risk, assessing core muscle function, and developing injury prevention programs. Moderate evidence of alterations in core muscle recruitment and injury risk exists. Assessment tools to identify deficits in volitional muscle contraction, isometric muscle endurance, stabilization, and movement patterns are available. Exercise programs to improve core stability should focus on muscle activation, neuromuscular control, static stabilization, and dynamic stability. CONCLUSION: Core stabilization relies on instantaneous integration among passive, active, and neural control subsystems. Core muscles are often categorized functionally on the basis of stabilizing or mobilizing roles. Neuromuscular control is critical in coordinating this complex system for dynamic stabilization. Comprehensive assessment and training require a multifaceted approach to address core muscle strength, endurance, and recruitment requirements for functional demands associated with daily activities, exercise, and sport.