Does low back pain affect the reliability of postural regulation?

The aim of this study was to examine the intraobserver reliability of a posturographic assessment in patients with low back pain. We investigated 24 symptomatic subjects with defined low back pain (mean: 57.9 years) and a pair-matched control group including 24 asymptomatic persons (mean: 58.1 years). Each participant underwent two measurements on a posturographic device (32 Hz sampling rate) based on the Interactive Balance System (time interval: 7 d). Test procedure consisted of tests on solid ground with eyes open (1) and eyes closed (2). Data analysis included parameters of motor output and a frequency band analysis. Reliability tests were realized using by intraclass correlations (ICC). Coefficients of ICC ranged from 0.36 (95% CI: 0.01-0.73) to 0.94 (95% CI: 0.86-0.97) in both test positions. For 69% (11/16) of the investigated parameters a high level (ICC > 0.75) of intraobserver reliability was reached. Based on the results, the posturographic measurement system used in this study seems to be appropriate for use in longitudinal study designs in an orthopaedic setting.

The influence of lumbopelvic control on shoulder and elbow kinetics in elite baseball pitchers.

BACKGROUND: Research has shown that diminished lumbopelvic control has a negative effect on pitching performance and can lead to more days on the disabled list. Despite the identified correlation between lumbopelvic control and injury, there is no research that has shown whether insufficient lumbopelvic control increases the force placed on the throwing arm. METHODS: Forty-three asymptomatic, National Collegiate Athletic Association Division I and professional minor league baseball pitchers participated. We measured the bilateral amount of anterior-posterior lumbopelvic tilt during a single-leg stance trunk stability test. We measured the shoulder and elbow kinetics of the throwing arm during the pitching motion using a 3-dimensional, high-speed video capture system. We used 2-tailed Pearson product-moment correlation coefficients (r) to determine the strength of the relationships between variables (P < .05). RESULTS: There were no significant relationships between the stride leg and any of the pitching kinetic variables (r < 0.23, P > .14). Similarly, there were no significant relationships between the drive leg and maximum shoulder distraction force, shoulder external rotation torque, or elbow distraction force (r <-0.24, P > .13). However, the drive leg did have significant relationships with both maximum shoulder horizontal torque (r = 0.44, P = .003) and elbow valgus torque (r = 0.46, P = .002). CONCLUSIONS: Our results show that a relationship exists between lumbopelvic control of the drive leg and both shoulder horizontal torque and elbow valgus torque during the throwing motion. Because of these relationships, clinicians should consider incorporating lumbopelvic control training exercises to minimize the kinetic force placed on the throwing shoulder and elbow during the pitching motion.

Descriptive Profile of Lumbopelvic Control in Collegiate Baseball Pitchers.

Laudner, K, Wong, R, Latal, J, and Meister, K. Descriptive profile of lumbopelvic control in collegiate baseball pitchers. J Strength Cond Res 32(4): 1150-1154, 2018-Throwing a baseball requires the transmission of forces generated in the lower extremity, through the trunk, then to the upper extremity, and ultimately out through the ball. Disruptions in this kinetic chain, specifically in lumbopelvic control, have been associated with decreased pitching performance and increased risk of injury. The purpose of this study was to establish normative data of lumbopelvic control among collegiate baseball pitchers. Data were compared bilaterally and with a group of nonthrowing physically active individuals. Eighteen asymptomatic pitchers and 30 nonthrowing subjects participated in this study. Each subject performed 6 separate tests bilaterally: single-leg balance, single-leg mini-squat, and static single-leg bridge. An iPod-based tilt sensor was placed around the waist of each subject and used to determine the amount of anterior-posterior lumbopelvic tilt during each test. Independent t tests showed that neither group had any bilateral differences in lumbopelvic control (p > 0.10). The groups had similar lumbopelvic tilt values during the single-leg balance (p > 0.08) and mini-squat tests (p > 0.72), but a significant difference during the bridge maneuver. For this test, the pitchers had less lumbopelvic control than the control group for both the lead leg (p = 0.003) and trail leg (p = 0.01). The descriptive values of this study may assist in designing lumbopelvic conditioning programs with the intent of enhancing pitching performance, as well as in the prevention, evaluation, and treatment of various injuries associated with lumbopelvic control deviations.

Effect of Ankle Positioning During Hamstring Stretches for Improving Straight Leg Hip Flexion Motion.

OBJECTIVE: To compare the effects of stretching the hamstrings with the ankle in either a plantar-flexed (PF) or dorsiflexed (DF) position for improving straight leg hip flexion range of motion (ROM) over a 4-week period. DESIGN: Randomized, single-blinded, pretest, posttest design. SETTING: Athletic training facility. PARTICIPANTS: Each limb of 34 asymptomatic individuals (15 males, 19 females) was randomly assigned to one of the 3 groups. Twenty-four limbs received hamstring stretches with the ankle in DF, 24 limbs received hamstring stretches with the ankle in PF, and 20 limbs received no stretch (control). INDEPENDENT VARIABLES: Ankle position (PF, DF) during hamstring stretching. MAIN OUTCOME MEASURES: We measured pretest and posttest passive straight leg hip flexion ROM with the test ankle in a neutral position. For the intervention groups, the test limb was passively stretched with the ankle held in end range DF or PF for their respective group. Each stretch was held for 30 seconds for a total of 3 applications. Two treatment sessions were completed per week for a total of 4 weeks. The control limbs received no stretching during the 4-week period. We conducted 1-way analyses of covariance to determine significant changes in ROM between groups (P < 0.05). RESULTS: There was no significant difference between treatment groups (P = 0.90), but a significant difference was found for both the PF (P = 0.04) and DF (P = 0.01) groups when compared with the control group. CONCLUSIONS: Our findings indicate that both stretching the hamstrings in either PF or DF improve straight leg hip ROM compared with a control group. CLINICAL RELEVANCE: The results of this study should be considered by clinicians when determining the optimal stretching techniques aimed at increasing hamstring length.

Intrarater reliability of goniometry and hand-held dynamometry for shoulder and elbow examinations in female team handball athletes and asymptomatic volunteers.

INTRODUCTION: To evaluate the intrarater reliability for examining active range of motion (ROM) and isometric strength of the shoulder and elbow among asymptomatic female team handball athletes and a control group using a manual goniometer and hand-held dynamometry (HHD). MATERIALS AND METHODS: 22 female team handball athletes (age: 21.0 ± 3.7 years) and 25 volunteers (13 female, 12 male, age: 21.9 ± 1.24 years) participated to determine bilateral ROM for shoulder rotation and elbow flexion/extension, as well as isometric shoulder rotation and elbow flexion/extension strength. Subjects were assessed on two separate test sessions with 7 days between sessions. Relative (intraclass correlation coefficients (ICC) and standard error of measurement (SEM) reliability were calculated. RESULTS: Reliability for ROM and strength were good to excellent for both shoulders and groups (athletes: ICC = 0.94-0.97, SEM 1.07°-4.76 N, controls: ICC = 0.96-1.00, SEM = 0.00 N-4.48 N). Elbow measurements for both groups also showed good-to-excellent reliability (athletes: ICC = 0.79-0.97, SEM = 0.98°-5.94 N, controls: ICC = 0.87-1.00, SEM = 0.00 N-5.43 N). CONCLUSIONS: It is important to be able to reliably reproduce active ROM and isometric strength evaluations. Using a standardized testing position, goniometry and HHD are reliable instruments in the assessment of shoulder and elbow joint performance testing. We showed good-to-excellent reproducible results for male and female control subjects and female handball athletes, although the single parameters in ROM and strength were different for each group and between the shoulders and elbows.

Decreased blood flow in the throwing arm of professional baseball pitchers.

BACKGROUND: As a consequence of the repetitive forces placed on the throwing arm of a baseball player, various bony, capsuloligamentous, and muscular adaptations occur and have been identified. However, no research has identified whether adaptations also exist in the vasculature of the upper extremity in the competitive baseball player. METHODS: Fifty-one professional baseball pitchers and 34 position players participated. Diagnostic ultrasound was used to measure bilateral blood flow of the brachial artery. These measurements were taken with the participant standing with the test arm resting at the participant's side and again with the test arm in a provocative shoulder position. RESULTS: The throwing arm of the pitchers had significantly less blood flow volume when in the provocative shoulder position compared with their nonthrowing arm (P = .01). Pitchers did not have any bilateral difference while in the resting position (P = .19). There were no bilateral differences among the position players while in the resting (P = .64) or provocative positions (P = .63). Pitchers had significantly less blood flow of the throwing shoulder while in the provocative position compared with position players (P = .02). There were no other between-group differences. CONCLUSIONS: While in a provocative shoulder position, pitchers have significantly less blood flow in their throwing arm compared with their nonthrowing arm and with the throwing arm of position players. These results provide a descriptive profile of blood flow volume among baseball players, which may be used in the evaluation and treatment of such athletes with vascular disorders.

Adductor longus activation during common hip exercises.

CONTEXT: Hip-adductor strains are among the most common lower-extremity injuries sustained in athletics. Treatment of these injuries involves a variety of exercises used to target the hip adductors. OBJECTIVE: To identify the varying activation levels of the adductor longus during common hip-adductor exercises. DESIGN: Descriptive study. SETTING: Laboratory. PARTICIPANTS: 24 physically active, college-age students. INTERVENTION: None. MAIN MEASUREMENT OUTCOMES: Peak and average electromyographic (EMG) activity of the adductor longus muscle during the following 6 hip-adductor rehabilitation exercises: side-lying hip adduction, ball squeezes, rotational squats, sumo squats, standing hip adduction on a Swiss ball, and side lunges. RESULTS: The side-lying hip-adduction exercise produced more peak and average activation than any other exercise (P < .001). Ball squeezes produced more peak and average activation than rotational squats, sumo squats, and standing adduction on a Swiss ball (P < .001). Ball squeezes had more average activation than side lunges (P = .001). All other variables for peak activation during the exercises were not statistically significant (P > .08). These results allowed the authors to provide an overall ranking system (highest to lowest muscle activation): side-lying hip adduction, ball squeezes, side lunges, standing adduction on a Swiss ball, rotational squats, and sumo squats. CONCLUSION: The study provides a ranking system on the activation levels of the adductor longus muscle for 6 common hip-adductor rehabilitation exercises, with the side-lying hip-adduction and ball-squeeze exercises displaying the highest overall activation.

Shoulder adaptations among pitchers and position players over the course of a competitive baseball season.

OBJECTIVE: To determine if throwing arm shoulder range of motion (ROM) and scapular kinematic differences exist between baseball pitchers and position players over the course of a baseball season. DESIGN: Prospective cohort. SETTING: Professional baseball athletic training room. PARTICIPANTS: Sixteen asymptomatic professional baseball pitchers and 16 position players. INDEPENDENT VARIABLES: Preseason glenohumeral (GH) posterior tightness and scapular position. MAIN OUTCOME MEASURES: Throwing arm GH horizontal adduction ROM and GH internal rotation bilateral asymmetry ROM, as well as bilateral differences in forward scapular posture and throwing arm scapular upward rotation at rest, 60, 90, and 120 degrees of humeral elevation were measured. These measurements were taken before and at the conclusion of a 140-game baseball season. RESULTS: Analyses of covariances showed no significant differences in GH horizontal adduction or internal rotation asymmetry ROM between groups over the course of the season. However, the pitchers developed significantly less scapular upward rotation at 60 degrees (P = 0.007) and 90 degrees (P = 0.006) of humeral elevation compared with the position players during the season. Forward scapular posture (P = 0.23) and scapular upward rotation at 0 degrees (P = 0.93) and 120 degrees (P = 0.29) of humeral elevation were not significantly different between groups. CONCLUSIONS: These results suggest that baseball position players develop more scapular upward rotation over the course of a competitive season than pitchers. This discrepancy may increase the pitchers' risk of injury and may partially explain their higher incidence of shoulder injury compared with position players. Therefore, pitchers may benefit from strengthening exercises and stretches aimed at increasing scapular upward rotation throughout the competitive baseball season.

The relationship between anterior glenohumeral laxity and proprioception in collegiate baseball players.

OBJECTIVE: To determine if a relationship exists between anterior glenohumeral (GH) laxity and proprioception. DESIGN: Cross-sectional study. SETTING: University biomechanics laboratory. PARTICIPANTS: Thirty asymptomatic collegiate baseball players. INDEPENDENT VARIABLES: Anterior GH laxity. MAIN OUTCOME MEASURES: Proprioception (active joint position sense) at positions of 75 degrees of external rotation, 30 degrees of external rotation, and 30 degrees of internal rotation were measured using an isokinetic dynomometer. Anterior GH laxity was measured using an instrumented arthrometer. RESULTS: Linear regression analyses showed that there were no relationships between anterior GH laxity and active joint position sense at 30 degrees of GH internal rotation and 30 degrees of GH external rotation (r = 0.21, P = 0.13). However, there was a moderate positive relationship between anterior GH laxity and joint position sense at 75 degrees of shoulder external rotation (r = 0.56, P = 0.001). CONCLUSIONS: These results suggest that shoulder proprioception in 75 degrees of external rotation decreases as anterior GH laxity increases. These results may prove beneficial in the prevention, evaluation, and treatment of various shoulder injuries associated with GH laxity.

Upper extremity sensorimotor control among collegiate football players.

Injuries stemming from shoulder instability are very common among athletes participating in contact sports, such as football. Previous research has shown that increased laxity negatively affects the function of the sensorimotor system potentially leading to a pathological cycle of shoulder dysfunction. Currently, there are no data detailing such effects among football players. Therefore, the purpose of this study was to examine the differences in upper extremity sensorimotor control among football players compared with that of a control group. Forty-five collegiate football players and 70 male control subjects with no previous experience in contact sports participated. All the subjects had no recent history of upper extremity injury. Each subject performed three 30-second upper extremity balance trials on each arm. The balance trials were conducted in a single-arm push-up position with the test arm in the center of a force platform and the subjects' feet on a labile device. The trials were averaged, and the differences in radial area deviation between groups were analyzed using separate 1-way analyses of variance (p < 0.05). The football players showed significantly more radial area deviation of the dominant (0.41 ± 1.23 cm2, p = 0.02) and nondominant arms (0.47 ± 1.63 cm2, p = 0.03) when compared with the control group. These results suggest that football players may have decreased sensorimotor control of the upper extremity compared with individuals with no contact sport experience. The decreased upper extremity sensorimotor control among the football players may be because of the frequent impacts accumulated during football participation. Football players may benefit from exercises that target the sensorimotor system. These findings may also be beneficial in the evaluation and treatment of various upper extremity injuries among football players.

Lack of a relationship between glenohumeral external-rotation strength and posterior shoulder tightness in baseball players.

CONTEXT: Posterior shoulder tightness has been associated with altered shoulder range of motion (ROM) and several pathologic entities in baseball players. This tightness is hypothesized to be the result of the cumulative stress placed on the posterior shoulder during the deceleration phase of the throwing motion. The role of the posterior shoulder static restraints is to absorb this load while the glenohumeral (GH) external rotators eccentrically decelerate the arm after ball release and therefore also help dissipate this force. As such, the authors hypothesized that if the GH external rotators are weak, an excessive amount of this deceleration force is placed on the static restraints, which may lead to subsequent tightness. OBJECTIVE: To compare the relationship between GH external-rotation strength and posterior shoulder tightness as measured by GH horizontal-adduction and internal-rotation ROM. DESIGN: Descriptive study. SETTING: Laboratory. PARTICIPANTS: 45 professional baseball players. MAIN OUTCOME MEASURES: GH external-rotation strength and GH horizontal-adduction and internal-rotation ROM. RESULTS: GH external-rotation strength showed no relationship with either GH horizontal-adduction ROM (r2 = .02, P = .40) or GH internal-rotation ROM (r2 = .002, P = .77). CONCLUSION: There is little to no relationship between GH external-rotation strength and posterior shoulder tightness in professional baseball players. The posterior static restraints of the shoulder may absorb a large majority of the deceleration forces during the throwing motion. Although strengthening of the posterior shoulder dynamic restraints should not be overlooked, routine stretching of the static restraints may be more beneficial for decreasing posterior shoulder tightness and the subsequent risks associated with this tightness, although future research is warranted.

Ankle muscle activation when using the Both Sides Utilized (BOSU) balance trainer.

The use of the Both Sides Utilized (BOSU) balance trainer has become increasingly popular among fitness and medical personnel. Many fitness facilities, physical therapy clinics, and athletic training rooms routinely use this piece of equipment for strengthening, balance training, functional assessments, and rehabilitating various injuries. However, there are currently little data describing the effectiveness of this balance device. Therefore, the purpose of this study was to determine which side of the BOSU balance trainer would generate a greater amount of tibialis anterior, peroneus longus, or medial gastrocnemius muscle activity using electromyography (EMG). Twenty, healthy, collegiate male subjects participated (age = 21.4 +/- 1.4 years; height = 179.4 +/- 8.6 cm; mass = 80.0 +/- 12.1 kg). Each subject performed 3 single-leg stance trials on each side of the BOSU balance trainer. The average EMG data from these trials were compared with maximal voluntary isometric contraction (MVIC) measures and represented an average percentage of these MVICs. We found no significant differences in EMG data for any muscle between conditions (p > 0.54). With regard to ankle muscle activity, both sides of the BOSU balance trainer produce similar difficulty during a balance training task. Therefore, no particular side of this device would provide any increase in muscle activity compared with the other side when used for improvements in balance or during the rehabilitation of lower extremity injuries.

Differences in Player Position Running Velocity at Lactate Thresholds Among Male Professional German Soccer Players.

This study investigated the differences in running velocities at specific lactate thresholds among male German soccer players. One hundred fifty-two professional (3rd league: n = 78; 4th league: n = 74) male soccer players (mean ± SD; age: 24.7 ± 4.37 years, body mass: 80.8 ± 7.33 kg, body height: 1.83 ± 0.06 m) volunteered for the investigation. Players were categorized as goalkeepers, central defenders, central midfielders, wings and forward. Players completed a treadmill test, at incremental speeds, to determine running velocity at different blood lactate concentrations (v2 = 2 mmol/l; v4 = 4 mmol/l; and v6 = 6 mmol/l). In addition, the largest difference between positions for running velocity was found at the lactate threshold v2 (p = 0.005). The running data revealed that only goalkeepers had significantly lower velocities at the lactate thresholds compared to outfield players. The central midfielders showed the highest average performance level at the lactate thresholds (v2: 12.5 ± 1.20 km/h; v4: 15.2 ± 1.14 km/h; and v6: 16.6 ± 1.14 km/h). In conclusion, this study provides soccer and position-specific reference data for the running performance of male professional German soccer players to evaluate the endurance performance in a standardized way. In this context, future research should extend the database for the first and second leagues. Further research assessing running performance during competition matches over the entire season is required to validate the endurance test performance data.

Comparison of a Combined Strength and Handball-Specific Training vs. Isolated Strength Training in Handball Players Studying Physical Education.

OBJECTIVES: The purpose of this study was to compare the effect of combined resistance training including handball-specific drill (CRT) with resistance training excluding handball-specific drill training (NSDT). MATERIALS AND METHODS: Twenty-two male handball players who studied physical education were randomly assigned to two groups: CRT (combined resistance training with sport-specific drill; n = 12) and NSDT (resistance training without any sport-specific drill training; n = 10). Over a 10-week period during the competitive season, the players performed a specific training program twice per week, which replaced their normal team handball training. The CRT regimen consisted of a combined (associated) resistance training and handball-specific drill, whereas the NSDT program consisted of a resistance training without handball-specific drill (dissociated). Pre- and post-test measures included squat jump and countermovement jumps, bench press, back half squats, throwing velocity during a 3-step jump throw, and a jump shot, repeated-sprint ability (six 2 × 15-m shuttle sprints) (RSA), medicine ball throw and anthropometric measurements. RESULTS: In both groups, significant intervention effects (d ≥ 1.0) were seen for all sprint (3/3), throwing (3/3) and jump (2/2) measures. Regarding maximal strength parameters, an effect size lower than 0.5 was only detected in the NSDT group for half back squats (d = 0.48). The largest effects were observed in the NSDT group for squat jump (d = 6.20) and medicine ball throw (d = 6.07). Interaction effects (group × time) were found for 50 % (5/10) of parameters. The greatest difference between groups regarding performance development over time was detected for jump shot (interaction effect: η²â€Š= 0.748). In contrast, there was no difference in performance development in both groups over time for RSAbest (interaction effect: η²â€Š= 0.025). CONCLUSIONS: The current findings suggest that during the competitive season, 10 weeks of CRT with only two training sessions per week improved numerous measures of athletic performance in handball students of physical education. Such conditioning should be highly recommended as part of the annual training program of handball players.

Mobility and stability adaptations in the shoulder of the overhead athlete: a theoretical and evidence-based perspective.

Overhead athletes require a delicate balance of shoulder mobility and stability in order to meet the functional demands of their respective sport. Altered shoulder mobility has been reported in overhead athletes and is thought to develop secondary to adaptive structural changes to the joint resulting from the extreme physiological demands of overhead activity. Researchers have speculated as to whether these structural adaptations compromise shoulder stability, thus exposing the overhead athlete to shoulder injury. Debate continues as to whether these altered mobility patterns arise from soft-tissue or osseous adaptations within and around the shoulder. Researchers have used quantitative techniques in an attempt to better characterize these structural adaptations in the shoulders of overhead athletes. Throwing athletes have been shown to display altered rotational range of motion (ROM) patterns in the dominant shoulder that favour increased external rotation and limited internal rotation ROM. Throwers also show a loss of horizontal or cross-body adduction in the throwing shoulder when compared with the non-throwing shoulder. This posterior shoulder immobility in the throwing shoulder is thought by some researchers to be associated with reactive scarring or contracture of the periscapular soft-tissue structures (e.g. posterior capsule and/or cuff musculature); however, evidence of reactive scarring or contractures of the posterior-inferior capsule or cuff musculature from anatomic or noninvasive imaging studies is lacking. Conversely, translational ROM (laxity) has been consistently shown to be symmetric between dominant and non-dominant shoulders of overhead athletes. From a skeletal perspective, throwing shoulders are shown to have more humeral retroversion when compared with the non-throwing shoulder. Alterations in humeral retroversion are thought to develop over time in young pre-adolescent throwers when the proximal humeral epiphysis is not yet completely fused. Even though the evidence is inconclusive at the present time, there is more compelling evidence that leads us to believe that altered shoulder mobility in the overhead-throwing athlete is more strongly associated with adaptive changes in proximal humeral anatomy (i.e. retroversion) than to structural changes in the articular and periarticular soft tissue structures. In addition, this retroversion is thought to account for the observed shift in the arc of rotational ROM in overhead athletes. However, in some athletes, capsulo-ligamentous adaptations such as anterior-inferior stretching or posterior-inferior contracture may become superimposed upon the osseous changes. This may ultimately lead to pathological manifestations such as secondary impingement, type II superior labrum from anterior to posterior (SLAP) lesions and/or internal (glenoid) impingement. Overuse injuries in the overhead athlete are a common and perplexing clinical problem in sports medicine and, therefore, it is imperative for sports medicine clinicians to have a thorough understanding of the short- and long-term effects of overhead activity on the shoulder complex. It is our intention that the information presented will serve as a guide for clinicians who treat the shoulders of overhead athletes.

ACUTE EFFECTS OF MUSCLE ENERGY TECHNIQUE AND JOINT MOBILIZATION ON SHOULDER TIGHTNESS IN YOUTH THROWING ATHLETES: A RANDOMIZED CONTROLLED TRIAL.

BACKGROUND: Posterior shoulder tightness (PST), defined as limited glenohumeral (GH) horizontal adduction and internal rotation motion, is a common occurrence in overhead athletes, particularly baseball and softball players, as a result of the extreme forces on the GH joint and the high number of throwing repetitions. Despite clinical evidence suggesting the use of joint mobilizations and muscle energy techniques (MET) for treating PST, there currently are no data examining the overall effectiveness of joint mobilizations and MET to determine optimal treatment for posterior shoulder tightness. PURPOSE: To compare the acute effectiveness of MET and joint mobilizations for reducing posterior shoulder tightness, as measured by passive GH horizontal adduction and internal rotation ROM, among high school baseball and softball players. STUDY DESIGN: Randomized controlled study. METHODS: Forty-two asymptomatic high school baseball and softball players were randomly assigned to one of three groups (14 MET, 14 joint mobilization, 14 control). Glenohumeral passive adduction and internal rotation ROM were measured in all participants in a pre-test post-test fashion. Between testing, the joint mobilization group received one application of GH posterior joint mobilizations. The MET group received one cycle of MET applied to the GH horizontal abductors. The control group received no intervention. Posttests measures were completed immediately following intervention or a similar amount of time resting for the control group and then again 15 minutes later. RESULTS: One-way analyses of covariance showed that the MET group had significantly more horizontal adduction ROM post-treatment compared to the control group (p = 0.04). No significant differences existed between groups in horizontal adduction (p > 0.16) or internal rotation (p>.28) or at the 15-minute posttests (p > 0.70). CONCLUSION: The results of this study indicate the application of MET to the horizontal abductors provides acute improvements to GH horizontal adduction ROM in high school baseball and softball players, while joint mobilizations provide no improvements. LEVEL OF EVIDENCE: 1.

Pre- and postoperative postural regulation following anterior cruciate ligament reconstruction.

There are currently no longitudinal data describing the pre- and postoperative postural regulation and stability of patients with anterior cruciate ligament (ACL) damage. Therefore, the aim of this study was to evaluate postural regulation and stability prior to and during rehabilitation following surgery of the ACL. Fifty-four physically active subjects (age: 30.5±10.9 years, 29 male subjects) were examined with the Interactive Balance System pre-, 6, and at 12 weeks following surgical reconstruction of the ACL using a hamstring tendon graft. The average period of time from injury to surgery was 27 days. Data were calculated with unifactorial and univariate analysis of variance. Significant effects were found for the somatosensory system (η2=0.115), stability indicator (η2=0.123), weight distribution index (η2=0.176), and synchronization (foot coordination) (η2=0.249). Involved side weight distribution (parameter: left) increased significantly (patients with left-sided/right-sided injury: η2=0.234/0.272). Load distribution to the heel remained stable during all three examination periods (η2=0.035 and η2=0.071), although a remarkable load at forefoot was observed. In seven out of 10 parameters partial effects were seen during the first 6 weeks after surgery. The results of this study indicated that injury of the ACL and subsequent surgical reconstructions result in postural regulation, with improvements in somatosensory system function, postural stability, weight distribution index, and foot coordination. Also, overloading of the injured side on the feet reduces significantly during rehabilitation. Thus, the initial phase of rehabilitation (weeks 1 to 6) seems to be more effective than the second period (weeks 6 to 12) postoperatively.

Reliability of an ice hockey-specific complex test.

BACKGROUND: This study assessed the intra-rater reliability of an ice hockey-specific complex test (IHCT) that reflects the intense multidirectional and intermittent efforts required in ice hockey. METHODS: Twenty professional players executed the IHCT twice over an interval of 2 days. Load parameters included a 10-m sprint, a 30-m transition with and without a puck, as well as slap and wrist shots. Stress parameters were lactate concentrations and heart rates. RESULTS: The intrarater reliability (ICC) ranged from 0.54 to 0.98 for load parameters, and from 0.26 to 0.87 for stress parameters. 33 % (3/9) of stress parameters and 82 % (18/22) of load parameters had an ICC > 0.75. The largest limits of agreement were 41.6 for slap shot 1 after test and 50.4 for 6-min heart rate recovery. The smallest were 0.40 (10-m sprint without a puck) and 5.36 (resting lactate). The intra-rater reliability as shown by the coefficient of variation (CV) was lower for stress than for load parameters (mean CV: 13.4 vs. 4.7). 68 % (15/22) of load parameters and 11 % (1/9) of stress parameters showed a CV below 5 %. CONCLUSION: The IHCT is currently the only ice hockey-specific complex test with scientifically tested reliability and validity that can analyze performance under conditions similar to competition. It is suggested that coaches, fitness coaches and sports scientists explore use of this test as a valid tool to assess players' performance and the effectiveness of training interventions.

National Athletic Trainers' Association Position Statement: Evaluation, Management, and Outcomes of and Return-to- Play Criteria for Overhead Athletes With Superior Labral Anterior-Posterior Injuries.

OBJECTIVE: To present recommendations for the diagnosis, management, outcomes, and return to play of athletes with superior labral anterior-posterior (SLAP) injuries. BACKGROUND: In overhead athletes, SLAP tears are common as either acute or chronic injuries. The clinical guidelines presented here were developed based on a systematic review of the current evidence and the consensus of the writing panel. Clinicians can use these guidelines to inform decision making regarding the diagnosis, acute and long-term conservative and surgical treatment, and expected outcomes of and return-to-play guidelines for athletes with SLAP injuries. RECOMMENDATIONS: Physical examination tests may aid diagnosis; 6 tests are recommended for confirming and 1 test is recommended for ruling out a SLAP lesion. Combinations of tests may be helpful to diagnose SLAP lesions. Clinical trials directly comparing outcomes between surgical and nonoperative management are absent; however, in cohort trials, the reports of function and return-to-sport outcomes are similar for each management approach. Nonoperative management that includes rehabilitation, nonsteroidal anti-inflammatory drugs, and corticosteroid injections is recommended as the first line of treatment. Rehabilitation should address deficits in shoulder internal rotation, total arc of motion, and horizontal-adduction motion, as well as periscapular and glenohumeral muscle strength, endurance, and neuromuscular control. Most researchers have examined the outcomes of surgical management and found high levels of satisfaction and return of shoulder function, but the ability to return to sport varied widely, with 20% to 94% of patients returning to their sport after surgical or nonoperative management. On average, 55% of athletes returned to full participation in prior sports, but overhead athletes had a lower average return of 45%. Additional work is needed to define the criteria for diagnosing and guiding clinical decision making to optimize outcomes and return to play.

Treadmill based reference running data for healthy subjects is dependent on speed and morphological parameters.

OBJECTIVE: To obtain spatiotemporal and dynamic running parameters of healthy participants and to identify relationships between running parameters, speed, and physical characteristics. METHOD: A dynamometric treadmill was used to collect running data among 417 asymptomatic subjects during speeds ranging from 10 to 24km/h. Spatiotemporal and dynamic running parameters were calculated and measured. RESULTS: Results of the analyses showed that assessing running parameters is dependent on running speed. Body height correlated with stride length (r=0.5), cadence (r=-0.5) and plantar forefoot force (r=0.6). Body mass also had a strong relationship to plantar forefoot forces at 14 and 24km/h and plantar midfoot forces at 14 and 24km/h. CONCLUSION: This reference data base can be used in the kinematic and kinetic evaluation of running under a wide range of speeds.