A SURVEY OF EXERCISE‐RELATED LEG PAIN IN COMMUNITY RUNNERS

Purpose/Background:

Exercise‐related leg pain (ERLP) is a common problem in runners. The purposes of this study were to 1) report ERLP occurrence among adult community runners; 2) determine ERLP impact on daily activities; and 3) determine if there is a relationship between ERLP occurrence and selected potential risk factors including sex, age, years of running, ERLP history, body mass index (BMI), orthotic use, menstrual function, and training variables.

Methods:

Community runners registered for a local race were invited to complete a questionnaire including demographics and potential risk factors. Analyses of differences (t‐test) and relationships (Chi‐square) were conducted and relative risk (RR) values were calculated.

Results:

225 registered runners (105 male, 120 female) participated; 63.6% reported ERLP history, and 35.1% reported ERLP in the 3 months preceding the race with bilateral medial ERLP as the most common presentation. Of the 79 runners who experienced ERLP during the 3 months preceding the race, ERLP caused 41.8% to reduce their running and interfered with walking or stair climbing in < 10%. Chi square analyses showed no significant association of sex, menstrual function, orthotic use, or BMI with ERLP occurrence. Significant associations were observed between ERLP history and ERLP occurrence in the previous year (RR=3.39; 2.54‐4.52 95% CI), and between ERLP in the 3 months preceding the race and both years running and training mileage. Greater ERLP occurrence was observed in runners with less than 3 years experience (RR = 1.53; 1.08‐2.17 95% CI) and runners who ran fewer than 15 miles/week (RR = 1.47; 1.04‐2.08 95% CI). Those runners with < 3 years running experience and a race pace of 9 min/mile or > were at greater risk for ERLP when compared to other participants (RR=1.53; 1.07‐2.18 95% CI).

Conclusion:

Interfering ERLP was common among this group of community runners. Risk factors included ERLP history, training mileage < 15 miles/week, and < 3 years running experience. Further investigation is warranted to identify factors which may increase a community runner''s risk of developing ERLP.

Level of Evidence:

2b.     

CLINICAL EXAMINATION AND PHYSICAL ASSESSMENT OF HIP JOINT‐RELATED PAIN IN ATHLETES

Evidence‐based clinical examination and assessment of the athlete with hip joint related pain is complex. It requires a systematic approach to properly differentially diagnose competing potential causes of athletic pain generation. An approach with an initial broad focus (and hence use of highly sensitive tests/measures) that then is followed by utilizing more specific tests/measures to pare down this imprecise differential diagnosis list is suggested. Physical assessment measures are then suggested to discern impairments, activity and participation restrictions for athletes with hip‐join related pain, hence guiding the proper treatment approach.

Level of Evidence:

5     

DIAGNOSTIC IMAGING OF THE THROWING ATHLETE’S SHOULDER

The diagnostic capabilities of advanced imaging have increasingly enabled clinicians to delineate between structural alterations and injuries more efficiently than ever before. These impressive gains have unfortunately begun to provide a reliance on imaging at the loss of quality in the clinical examination. Ideally, imaging of the shoulder complex is performed to confirm the provisional diagnosis developed from the history and clinical exam rather than to create such. This clinical commentary will provide the framework for both basic and advanced uses of imaging as well as discussion of evolving modalities.

Level of Evidence:

5     

THE RELIABILITY,MINIMAL DETECTABLE CHANGE AND CONSTRUCT VALIDITY OF A CLINICAL MEASUREMENT FOR QUANTIFYING POSTERIOR SHOULDER TIGHTNESS IN THE POST‐OPERATIVE POPULATION

Background:

Posterior shoulder tightness (PST) has been implicated in the etiology of numerous shoulder disorders. Although reliable and valid measures have been described for the non‐operative population one does not exist for the post‐operative population.

Study Design:

Blinded repeated measures design.

Purpose:

Investigate the intrarater reliability, minimal detectable change at the 90% confidence interval (MDC₉₀) and construct validity of an inclinometric measurement designed to quantify PST in the post‐operative population.

Methods:

One investigator performed PST measurements on the operative shoulder of 23 participants. Passive internal and external rotation measurements were performed for the validity component of the investigation.

Results:

Intrarater reliability using an intraclass correlation coefficient (ICC) model 3,k was good (ICC = 0.79). The MDC₉₀ indicated that a change of greater than or equal to 8 degrees would be required to be 90% certain that a change in the measurement would not be the result of inter‐trial variability or measurement error. Construct validity was supported by a statistically significant relationship between PST and internal rotation r = 0.54 and by a relationship between PST and external rotation r = 0.30 which was not statistically significant.

Conclusion:

The sidelying procedure described in this investigation appears to be a reliable and valid means for quantifying PST in the post‐operative population. Moreover, the use of inclinometry provides an absolute angle of tightness that may be used for intersubject comparison, documenting change, and to determine reference values.

Level of Evidence:

Therapy, level 2b     

PRE‐OPERATIVE LOW BACK PAIN NEGATIVELY AFFECTS SELF‐REPORTED FUNCTION IN INDIVIDUALS UNDERGOING HIP ARTHROSCOPY

Background/Purpose

Low back pain (LBP) is a common source of disability in adults and highly prevalent in patients with painful hip pathology. Persistent LBP after hip arthroplasty is associated with lower self‐reported function, however, the effect of pre‐operative LBP in patients undergoing hip arthroscopy for FAI has not been evaluated. The purpose of this study was to determine whether improvements in self‐reported hip function following arthroscopic surgery for femoroacetabular impingement (FAI) differed between those with and without reports of pre‐operative low back pain.

Study Design

Cohort

Methods

Three hundred eighteen subjects undergoing primary hip arthroscopy for clinically and radiographically‐confirmed FAI were recruited and consented. One hundred fifty‐six of these subjects completed the International Hip Outcomes Tool (iHOT‐33) and the Hip Outcome Score Activities of Daily Living Subscale (HOS‐ADL) before, and six and 12 months after surgery. Subjects were grouped based on the self‐reported presence or absence of LBP prior to arthroscopy. A repeated measures analysis of variance was used to determine the effects of time and low back pain on iHOT‐33 and HOS‐ADL scores.

Results

Seventy‐five of 156 subjects (48.1%) reported LBP prior to surgery. A main effect of time was found for both outcome measures (p<0.001), demonstrating improvement in self‐reported outcomes over the testing period. There was a main effect of group for the iHOT‐33 (LBP: 52.0 [47.9,56.0]; no LBP 57.9 [53.9,61.8]; p = 0.043) but not for the HOS‐ADL (LBP: 75.2 [72.2,78.2]; no LBP 78.8 [75.9,81.7]; p = 0.088) indicating that subjects with pre‐operative LBP had poorer self‐reported function per the iHOT‐33 compared to those without LBP.

Conclusion

Self‐reported hip function scores improved regardless of the presence of pre‐operative LBP; however subjects with LBP reported poorer self‐reported function per the iHOT‐33 as compared to those without LBP up to 12 months post‐operatively.

Level of Evidence

3c     

INTRA‐RATER AND INTER‐RATER RELIABILITY OF THE FIVE IMAGE‐BASED CRITERIA OF THE FOOT POSTURE INDEX‐6

Purpose/Background:

The Foot Posture Index‐6 (FPI‐6) is considered a simple quantification tool to assess static foot alignment. Palpation of the foot is required for assessment of one of the six criteria that comprise the FPI‐6; the remaining five criteria may be evaluated using still‐frame photographs. Using only the image‐based criteria may allow multiple clinicians to evaluate large groups of patients quickly. Reliability using only these five image‐based criteria has not been established. The purposes of the current study were to establish the inter‐ and intra‐rater reliability using five image‐based criteria from the Foot Posture Index‐6 (FPI‐6) as well as to examine the agreement between the raters in identifying foot type using the composite five FPI scores.

Methods:

Forty participants (23 females, 17 males; 23.67 ± 8.49 years; 64.59 ± 14.43 kg; 166.07 ± 11.79 cm) volunteered for this study. An investigator took three photos with a digital camera of the medial longitudinal arch, posterior ankle, and of the talonavicular joint approximately 45° from the posterior calcaneus for both right and left feet. Two investigators assessed the five image‐based criteria of the FPI‐6 for both feet of 40 participants on three occasions separated by a day. Inter‐and intra‐rater reliability were assessed with Intraclass Correlation Coefficients (ICC_3,2). The amount of agreement for classification of foot posture type between the two raters was assessed with Cohen''s kappa coefficient. Significance was set a priori at P < 0.05.

Results:

The inter‐rater reliability was poor to moderate for all three sessions (ICC_3,2 = 0.334‐0.634). For the foot posture classification, the amount of agreement between two raters was poor for left (κ= 0.12) and right (κ= 0.19) feet. The intra‐rater reliability was excellent for left (ICC_3,2=0.956) and right feet (ICC_3,2=0.959).

Conclusions:

Excellent intra‐rater and poor to moderate inter‐rater reliability was found using only the five image‐based criteria of the FPI‐6. However, the classification of foot posture did not improve the amount of agreement between raters. Therefore, caution is needed when interpreting FPI scores from five image‐based criteria.

Levels of Evidence:

3b     

PREVALENCE OF ANTERIOR KNEE PAIN IN 18–35 YEAR-OLD FEMALES

Purpose/Background:

Anterior knee pain (AKP), also known as patellofemoral pain syndrome (PFPS), is believed to be common in young, active females. A prevalence rate of 25% has been commonly cited in the literature. However, this rate may be more anecdotal than empirical. The purpose of this study was to estimate the prevalence of AKP in females 18 to 35 years of age.

Methods:

Three cohorts of females, totaling 724 participants between 18 and 35 years of age participated in this study. The mean age of participants was 24.17 years (SD: 2.34), mean height was 165.10 cm (SD: 7.26), mean weight was 65.46 kg (SD: 14.10), and mean BMI was 23.95 kg/m2 (SD: 4.86). Participants completed the Anterior Knee Pain Questionnaire (AKPQ), a functional outcome tool developed to document symptoms of AKP and progress in patients during rehabilitation.

Results:

The mean score on the AKPQ for the left lower extremity was 93.38 (SD: 10.00) and 93.16 (SD: 11.37) for the right lower extremity. Using a cutoff score of 83 on the AKPQ, 85 of 724 subjects were classified as having AKP in the left lower extremity for a prevalence of 12% (95% CI = 9%-14%) while 94 subjects were classified with AKP in the right lower extremity for a prevalence of 13% (95% CI = 11%-15%).

Conclusion:

The estimated prevalence of AKP in this sample of 18–35 year old females of 12–13% is much less than the commonly cited value of 25%. The results may provide a better representation of subjects with AKP.

Level of Evidence:

3     

COMPARING THE EFFECTS OF SELF‐MYOFASCIAL RELEASE WITH STATIC STRETCHING ON ANKLE RANGE‐OF‐MOTION IN ADOLESCENT ATHLETES

Background:

Increased flexibility is often desirable immediately prior to sports performance. Static stretching (SS) has historically been the main method for increasing joint range‐of‐motion (ROM) acutely. However, SS is associated with acute reductions in performance. Foam rolling (FR) is a form of self‐myofascial release (SMR) that also increases joint ROM acutely but does not seem to reduce force production. However, FR has never previously been studied in resistance‐trained athletes, in adolescents, or in individuals accustomed to SMR.

Objective:

To compare the effects of SS and FR and a combination of both (FR+SS) of the plantarflexors on passive ankle dorsiflexion ROM in resistance‐trained, adolescent athletes with at least six months of FR experience.

Methods:

Eleven resistance‐trained, adolescent athletes with at least six months of both resistance‐training and FR experience were tested on three separate occasions in a randomized cross‐over design. The subjects were assessed for passive ankle dorsiflexion ROM after a period of passive rest pre‐intervention, immediately post‐intervention and after 10, 15, and 20 minutes of passive rest. Following the pre‐intervention test, the subjects randomly performed either SS, FR or FR+SS. SS and FR each comprised 3 sets of 30 seconds of the intervention with 10 seconds of inter‐set rest. FR+SS comprised the protocol from the FR condition followed by the protocol from the SS condition in sequence.

Results:

A significant effect of time was found for SS, FR and FR+SS. Post hoc testing revealed increases in ROM between baseline and post‐intervention by 6.2% for SS (p < 0.05) and 9.1% for FR+SS (p < 0.05) but not for FR alone. Post hoc testing did not reveal any other significant differences between baseline and any other time point for any condition. A significant effect of condition was observed immediately post‐intervention. Post hoc testing revealed that FR+SS was superior to FR (p < 0.05) for increasing ROM.

Conclusions:

FR, SS and FR+SS all lead to acute increases in flexibility and FR+SS appears to have an additive effect in comparison with FR alone. All three interventions (FR, SS and FR+SS) have time courses that lasted less than 10 minutes.

Level of evidence:

2c     

COMPARISON OF THE EFFECTS OF AN EIGHT‐WEEK PUSH‐UP PROGRAM USING STABLE VERSUS UNSTABLE SURFACES

Background and Purpose:

Recently, the trend among physical training and rehabilitation professionals is the use of resistance exercise on unstable equipment in order to increase the effort of the agonist and stabilizing muscles. It is unknown if performing exercises on unstable surfaces provides a greater training stimulus as compared to training on a stable training surface. Therefore, the purpose of this research was to compare the effect that push‐up training on stable and unstable surfaces had on strength performance in healthy young men.

Methods:

Thirty subjects with experience in resistance training participated in push‐up training two days per week for eight weeks on one of three different surfaces: the floor (Tp), the T‐Bow® (TBp) or the BOSU® (Bp).

Results:

Strength, as measured by one repetition maximum (1‐RM) and muscle endurance, as measured by number of pushups performed did not improve significantly (p>0.05) for any of the intervention groups.

Conclusions:

The addition of unstable surfaces in push‐up training does not provide greater improvement in muscular strength and endurance than push up training performed on a stable surface in young men.

Levels of Evidence:

3b     

A TOTAL MOTION RELEASE WARM‐UP IMPROVES DOMINANT ARM SHOULDER INTERNAL AND EXTERNAL ROTATION IN BASEBALL PLAYERS

Context:

Current literature indicates a correlation between decreased total shoulder range of motion (ROM) and internal rotation (IR) of the dominant arm and increased injury risk in throwers. The optimal method for increasing shoulder ROM, improving performance, and preventing injury is unknown. It is also unknown if treating the non‐dominant arm may affect ROM on the dominant side.

Purpose:

To explore the effect of the Total Motion Release (TMR®) Trunk Twist (TT) and Arm Raise (AR) on IR and external rotation (ER) of the dominant shoulder in baseball players compared to a traditional dynamic warm‐up.

Design:

Cohort study.

Setting:

University athletic training clinic and baseball field.

Participants:

Pitchers (males, n = 10; age, 18.6 ± 1.3) recruited from local baseball teams were randomly assigned two one of two groups: TMR® treatment group (TMRG; n = 5) or traditional warm‐up group (TWG; n = 5).

Interventions:

Baseline IR and ER goniometry range of motion (ROM) measurements were recorded. The TMRG then completed the TMR® exercises and post‐intervention measurements. The TWG completed a traditional static and dynamic warm‐up (e.g., lunges, power skips, sprints, sleeper stretch) and then completed post‐intervention measurements. Following the completion of those measurements, the TWG completed the TMR® Trunk Twist and Arm Raise protocol and had post‐intervention measurements recorded once more.

Main Outcome Measures:

ROM measures for IR and ER of the dominant shoulder. Alpha level was set at p ≤ 0.05.

Results

Significant differences were present for IR (p = 0.025) and ER (p = 0.014) between the TMRG and the TWG after initial intervention. Significant differences for IR were present in the TWG between baseline and TMR® intervention and traditional warm‐up and TMR® intervention. For the TWG, changes in ER were not statistically significant at baseline, post‐warm‐up, or post‐ TMR® intervention. Significant differences were not present for IR (p = 0.44) or ER (p = 0.23) between groups once TMR® had been completed by both groups.

Conclusions:

TMR® produced larger increases in IR and ER of the throwing shoulder when compared to the TWG. Generalizability is limited, however, by the low number of participants in each group and a potential ceiling effect of attainable ROM gains. Future studies should examine if using a full TMR® treatment process is more beneficial. Additionally, future research should compare TMR® intervention to other warm‐up activities or stretching protocols (e.g. resistance tubing, weighted balls) and examine its effect across other variables (e.g., injury rates, throwing velocity).

Level of Evidence:

Clinical Evidence Based Level 2b     

RELATIONSHIP BETWEEN HIP STRENGTH AND TRUNK,HIP, AND KNEE KINEMATICS DURING A JUMP‐LANDING TASK IN INDIVIDUALS WITH PATELLOFEMORAL PAIN

Background/Purpose:

Decreased strength of the hip musculature and altered mechanics of the lower extremity have been identified in individuals with patellofemoral pain (PFP). The aim of this study was to determine if a relationship exists between hip muscle strength and transverse and frontal plane motion at the hip and knee, and ipsilateral trunk flexion during a jump‐landing task in individuals with PFP.

Methods:

Fifteen individuals (10 females, 5 males) with PFP participated in this investigation. A three‐dimensional motion analysis system was utilized to assess trunk, hip, and knee kinematics during a jump‐landing task. An isokinetic dynamometer was utilized to assess concentric and eccentric strength of the hip musculature. Simple correlation analyses were performed to determine the relationships between hip muscle strength and peak frontal and transverse plane hip and knee kinematics and ipsilateral trunk flexion.

Results:

Decreased eccentric strength of the hip external rotators and abductors was significantly correlated to increased frontal plane motion at the hip and trunk, respectively (P<0.05).

Conclusions:

Based on these findings, eccentric strengthening exercises for the hip musculature may be an important component for clinicians to include when rehabilitating individuals with PFP who display increased frontal plane motion at the hip and trunk.

Level of Evidence:

2b     

THE ACUTE EFFECTS OF VARIOUS TYPES OF STRETCHING STATIC,DYNAMIC, BALLISTIC,AND NO STRETCH OF THE ILIOPSOAS ON 40‐YARD SPRINT TIMES IN RECREATIONAL RUNNERS

Background and Purpose:

The potential adverse effects of static stretching on athletic performance are well documented, but still appears to be controversial, especially as they relates to sprinting. The prevalence of this practice is demonstrated by the number of competitive and recreational athletes who regularly engage in stretching immediately prior to sprinting with the mindset of optimizing their performance. The purpose of this study was to examine the effects of acute static, dynamic, and ballistic stretching, and no stretching of the iliopsoas muscle on 40‐yard sprint times in 18‐37 year‐old non‐competitive, recreational runners.

Methods:

Twenty‐five healthy recreational runners (16 male and 9 female) between the ages of 24 and 35 (Mean = 26.76 yrs., SD = 2.42 yrs.) completed this study. A repeated measures design was used, which consisted of running a 40‐yard sprint trial immediately following each of 4 different stretching conditions aimed at the iliopsoas muscle and lasting 1 minute each. The 4 conditions were completed in a randomized order within a 2‐week time period, allowing 48‐72 hours between each condition. Prior to each 40‐yard sprint trial, a 5‐minute walking warm‐up was performed at 3.5 mph on a treadmill. The subject then ran a baseline 40‐yard sprint. After a 10‐minute self‐paced walk, each subject performed one of the 4 stretching conditions (ballistic, dynamic, static, and no stretch) and then immediately ran a timed 40‐yard sprint.

Results:

There was a significant interaction between stretching conditions and their effects on sprint times, F(3,72) = 9.422, p<.0005. To break down this interaction, simple main effects were performed with 2 repeated measures ANOVAs and 4 paired t‐tests using a Bonferroni corrected alpha (α = .0083). There were no significant differences between the 4 pre‐condition times, p = 0.103 (Greenhouse‐Geisser) or the post‐condition times, p = 0.029. In the no stretch condition, subjects improved significantly from pre‐ to post‐ sprint times (p<0.0005). There were no statistically significant differences in pre‐ and post‐stretch condition sprint times among the static (p = 0.804), ballistic (p = 0.217), and dynamic (p = 0.022) stretching conditions.

Conclusions:

Sprint performance may show greatest improvement without stretching and through the use of a walking generalized warmup on a treadmill. These findings have clinically meaningful implications for runners who include iliopsoas muscle stretching as a component of the warm‐up.

Level of Evidence:

Level 2     

THE VALIDITY OF 2‐DIMENSIONAL MEASUREMENT OF TRUNK ANGLE DURING DYNAMIC TASKS

Purpose/Background:

Injury screening methods that use three‐dimensional (3D) motion analysis accurately predict the risk of injuries, yet are expensive. There is great need for valid, cost‐effective techniques that can be used in large‐scale assessments. Utilizing two‐dimensional (2D) measures of lateral trunk motion may identify athletes at risk for lower extremity injury. The purpose of this research was to determine the strength of the relationships between 2D and 3D calculations of lateral trunk angle for female athletes performing a single‐leg cross drop landing.

Methods:

Twenty‐one high‐school female volleyball players performed a single‐leg cross drop landing onto a force plate. The 3D angular trunk motion was calculated, and four different 2D measures of lateral trunk angle were calculated for both left and right landing leg. A one‐way multivariate analysis of variance was used to compare 2D measures to the 3D measurements, and Pearson correlations were used to determine the strength of these relationships.

Results:

The angle formed by the medial shoulder joint center, medial ASIS, and vertical line (LTA4) was similar to the 3D measures of lateral trunk angle during landing (r‐values ≥ 0.62; p‐values ≤ 0.003; mean differences, ‐1.0° to 1.2°).

Conclusions:

Given the recent focus on the role of the trunk in lower extremity injury, using the 2D LTA4 assessment may expand existing assessments into a composite model that can more accurately assess female athletes at risk for injury than models that do not include trunk analysis.

Clinical Relevance:

Existing models that enable clinicians to effectively identify female athletes at risk for lower extremity injury may be enhanced by including accurate assessments of lateral trunk motion.     

THE RELATIONSHIP BETWEEN GLENOHUMERAL JOINT TOTAL ROTATIONAL RANGE OF MOTION AND THE FUNCTIONAL MOVEMENT SCREEN? SHOULDER MOBILITY TEST

Purpose/Background:

Side to side asymmetry in glenohumeral joint rotation correlates with injury risk in overhead athletes. The purpose of the current study was to identify the relationship between side‐to‐side asymmetries in glenohumeral joint total rotational range of motion and shoulder mobility test scores from the Functional Movement Screen™ in collegiate overhead athletes. The authors hypothesized that asymmetries of > 10° in glenohumeral total rotation would not be associated with asymmetrical findings in the Functional Movement Screen™ (FMS) shoulder mobility test.

Methods:

Passive glenohumeral total rotational range of motion and the shoulder mobility test of the FMS were measured during pre‐participation examinations in 121 NCAA male and female Division II collegiate overhead athletes from varied sports. Passive shoulder range of motion was measured in supine at 90° of abduction, with the humerus in the scapular plane using two measurers and a bubble goniometer. A Pearson Chi‐square analysis, p<.05 was used to associate the presence of asymmetries in glenohumeral joint rotation and in the FMS shoulder mobility test in each subject.

Results:

40/114 (35.1%) athletes demonstrated asymmetries in total glenohumeral rotation. 45/114 (39.5%) athletes demonstrated asymmetries in the shoulder mobility test. Only 17 of the 45 subjects who demonstrated asymmetry on the shoulder mobility test also demonstrated glenohumeral joint rotation differences of > 10°. Athletes with asymmetries in rotation of > 10° were not any more likely to have asymmetries identified in the shoulder mobility test (95% CI=.555‐2.658, P=.627).

Conclusions

Glenohumeral joint range of motion is one of multiple contributors to performance on the FMS shoulder mobility test, and alone, did not appear to influence results. The FMS shoulder mobility test should not be used alone as a means of identifying clinically meaningful differences of shoulder mobility in the overhead athlete. Clinicians working with overhead athletes may consider using both assessments as a complete screening tool for injury prevention measures.

Level of Evidence:

Level 3     

EFFECTS OF A SEASON OF SUBCONCUSSIVE CONTACT ON CHILD‐ SCAT3 SCORES IN 8‐12 YEAR‐OLD MALE ATHLETES

Background

Each year, over 173,000 children and adolescents visit emergency departments due to sports and recreation related concussions, an increase of 60% over the last decade due to the rise in the number of children participating in sport. While numerous authors have sought to address the epidemiology of concussions across multiple age groups who participate in contact sports, a recent review of literature did not reveal a substantial amount of published articles that addressed the issue of subconcussive contact. Multiple tools have been developed to assess acute episodes of concussion. Among the assessment protocols many include an assessment of balance, short and long term memory recall, and balance. The Child‐SCAT3 was designed specifically to evaluate concussions in children 5‐12 years of age.

Objective

The purpose of this study was to determine the effect of a season of subconcussive contact on Child‐SCAT3 scores in 8‐12 year old males compared to their age matched peers who participated in non‐contact sports. A secondary purpose was to evaluate how scores of the sub‐ components of the Child‐SCAT3 compare between contact and non‐contact athletes.

Design

A prospective cohort study was performed of 71 male athletes (58 football, 13 baseball) ages 8‐12 (contact mean age 10.30 years, SD 1.20; non‐contact mean age 10.03 years, SD 1.26) over the course of a season.

Methods

Portions of The Child‐SCAT3 were administered and scored in pre‐adolescent athletes prior to and following a season of participation in football (contact sport group) and baseball (non‐contact sport group). The outcome measures of interest included the portions related to Cognitive ability, Balance, and Coordination.

Results

No statistically significant differences were found in group, time or time and group interaction for any of the utilized portions of the Child‐SCAT3. Statistically significant differences were found between groups for preseason cognitive orientation and postseason immediate memory. Cognitive orientation and coordination were also found to be statistically significantly improved across both groups over the course of the season.

Limitations

This study was potentially limited by the number of control subjects tested.

Conclusions

A season of subconcussive contact in football was not detrimental to cognitive and balance scores on the Child‐SCAT3.

Level of Evidence

3     

IMMEDIATE EFFECTS OF A DYNAMIC ROTATION‐SPECIFIC WARM‐UP ON X‐FACTOR AND X‐FACTOR STRETCH IN THE AMATEUR GOLFER

Background

Recent evidence suggests performing a warm‐up prior to golf can improve performance and reduce injuries. While some characteristics of effective golf warm‐ups have been determined, no studies have explored the immediate effects of a rotational‐specific warm‐up with elements of motor control on the biomechanical aspects of the full X‐Factor and X‐Factor Stretch during the golf swing.

Methods

Thirty‐six amateur golfers (mean ± SD age: 64 ± 8 years old; 75% male) were randomized into a Dynamic Rotation‐Specific Warm‐up group (n=20), or a Sham Warm‐up group (n=16). X‐Factor and X‐Factor Stretch were measured at baseline and immediately following the warm‐up. Mixed model ANCOVAs were used to determine if a Group*Time interaction existed for each variable with group as the between‐subjects variable and time as the within‐subjects variable.

Results

The mixed model ANCOVAs did not reveal a statistically significant group*time interaction for X‐Factor or X‐Factor Stretch. There was not a significant main effect for time for X‐Factor but there was for X‐Factor Stretch. These results indicate that neither group had a significant effect on improving X‐Factor, however performing either warm‐up increased X‐Factor Stretch without significant difference between the two.

Conclusions

The results of this study suggest that performing the Dynamic Rotation‐Specific Warm‐up did not increase X‐Factor or X‐Factor Stretch when controlled for age compared to the Sham Warm‐up. Further study is needed to determine the long‐term effects of the Dynamic Rotation‐Specific Warm‐up on performance factors of the golf swing while examining across all ages.

Level of Evidence

2b     

THE VALIDITY OF PLANTARFLEXOR STRENGTH MEASURES OBTAINED THROUGH HAND‐HELD DYNAMOMETRY MEASUREMENTS OF FORCE

Purpose/Background:

Hand‐held dynamometers are commonly used to assess plantarflexor strength during rehabilitation. The purpose of this study was to determine the concurrent validity of measuring plantarflexion force using a hand‐held dynamometer (HHD) as compared to an electromechanical dynamometer as the gold standard. The hypothesis was that plantarflexor forces obtained using a hand‐held dynamometer would not show absolute agreement with a criterion standard.

Design:

Concurrent validity assessment for a diagnostic strength testing device.

Setting:

Institutional clinic and research laboratory

Participants:

Volunteer sample of healthy university students (N=20, 10 women, 10 men; 25.9±4.1 years).

Main Outcome Measure(s):

Maximal plantarflexion strength was measured using both a HHD and an electromechanical dynamometer (EMD) as a criterion measure.

Results:

Plantarflexor force measures with the HHD were significantly different (p<0.01) and not correlated with plantarflexor forces measured using the EMD for either limb (R² ≤ 0.09).

Conclusions:

Plantarflexor strength measurements acquired using HHD are different from those acquired using an EMD and are likely influenced by the strength of the examiner.

Level of Evidence:

Prospective cohort study, level II     

REAL‐TIME TEST‐RETEST AND INTERRATER RELIABILITY OF SELECT PHYSICAL PERFORMANCE MEASURES IN PHYSICALLY ACTIVE COLLEGE‐AGED STUDENTS

Background:

A new 16‐item physical performance measure screening battery (16‐PPM) was developed in order to expand on established movement based qualitatively scored functional screening batteries to encompass a broader spectrum of quantitatively scored functional constructs such as strength, endurance, and power.

Purpose/Hypothesis:

The purpose of this study was quantify the real‐time tests‐retest and expert versus novice interrater reliability of the 16‐PPM screen on a group of physically active college‐aged individuals. The authors'' hypothesized that the test‐retest and interrater reliability of quantitatively‐scored performance measures would be highly correlated (ICC ≥ 0.75) and that qualitatively‐scored movement screening tests would be moderately correlated (K_w = 0.41‐0.60).

Study Design:

Cohort reliability study

Methods:

Nineteen (8 males, 11 females) healthy physically active college‐aged students completed the 16‐PPM on two days, one week apart.

Results:

The majority of the quantitatively scored components of the 16‐PPMs demonstrated good expert‐novice interrater reliability (ICC > 0.75), while qualitatively scored tests had moderate (K_w = 0.41‐0.60) to substantial (K_w = 0.61‐0.80) agreement. Test‐retest reliability was consistent between raters, with most quantitatively scored PPMs exhibiting superior reliability to the qualitatively scored PPMs.

Conclusions:

The 16‐PPM test items showed good test‐retest and interrater reliability. However, results indicate that expert raters may be more reliable than novice raters for qualitatively scored tests. The validity of this 16‐PPM needs to be determined in future studies.

Clinical Relevance:

Physical performance screening batteries may be used to help identify individuals at risk for future athletic injury; however, current PPMs that rely on qualitatively scored movement screens have exhibited inconsistent and questionable injury prediction validity. The addition of reliable quantitatively scored PPMs may complement qualitatively scored PPMs to improve the battery''s predictive ability.

Level of Evidence:

Level III