Lane Bailey

The Immediate Reduction in Low Back Pain Intensity Following Lumbar Joint Mobilization and Prone Press-ups Is Associated With Increased Diffusion of Water in the L5-S1 Intervertebral Disc

STUDY DESIGN Single-group, prospective, repeated-measures design. OBJECTIVES To determine differences in the changes of diffusion of water in the L5-S1 intervertebral disc between subjects with nonspecific low back pain (LBP) who reported an immediate reduction in pain intensity of 2 or greater on an 11-point (0-10) numeric rating scale after a 10-minute session of lumbar joint mobilization, followed by prone press-up exercises, compared to those who did not report an immediate reduction in pain intensity of 2 or greater on the pain scale. BACKGROUND Combining lumbar joint mobilization and prone press-up exercises is a common intervention for patients with LBP; however, there is conflicting evidence regarding the effectiveness and efficacy of this approach. Increased knowledge of the physiologic effects of the combined use of these treatments, and the relationship to pain reports, can lead to refinement of their clinical application. METHODS Twenty adults, aged 22 to 54, participated in this study. All subjects reported LBP of at least 2 on an 11-point (0-10) verbally administered numeric rating scale at the time of enrollment in the study and were classified as being candidates for the combination of joint mobilization and prone press-ups. Subjects underwent T2- and diffusion-weighted lumbar magnetic resonance imaging scans before and immediately after receiving a 10-minute session of lumbar pressures in a posterior-to-anterior direction and prone press-up exercises. Subjects who reported a decrease in current pain intensity of 2 or greater immediately following treatment were classified as immediate responders, while the remainder were classified as not-immediate responders. The apparent diffusion coefficient, representing the diffusion of water in the nucleus pulposis, was calculated from the midsagittal diffusion-weighted images. RESULTS Following treatment, immediate responders (n = 10) had a mean increase in the apparent diffusion coefficient in the middle portion of the L5-S1 intervertebral disc of 4.2% compared to a mean decrease of 1.6% for the not-immediate responders (P<.005). CONCLUSION In a group of subjects with LBP, who were classified as being candidates for extension-based treatment, the report of an immediate reduction in pain intensity of 2/10 of greater after a treatment of posterior-to-anterior-directed pressures, followed by prone press-up exercises, was associated with an increase in diffusion of water in the nuclear region of the L5-S1 intervertebral disc. Subjects who did not report a pain reduction of at least 2/10 did not have a change in diffusion. J Orthop Sports Phys Ther 2010;40(5):256-264, Epub 12 March 2010. doi:10.2519/jospt.2010.3284.

Professional Pitchers With Glenohumeral Internal Rotation Deficit (GIRD) Display Greater Humeral Retrotorsion Than Pitchers Without GIRD

Background: Dominant shoulder glenohumeral internal rotation deficit (GIRD) has been associated with pitching arm injuries. The relationship of humeral torsion on development of GIRD is not clear. Hypothesis: Pitchers displaying GIRD will display greater humeral retrotorsion when compared with those without GIRD. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Humeral torsion and shoulder range of motion (ROM) were measured in 222 professional pitchers before spring training from 2009 to 2012. Shoulder external rotation (ER) and internal rotation (IR) ROM were assessed in 90° of abduction with the scapula stabilized. Humeral torsion was measured via ultrasound using previously described and validated methods. Side-to-side differences in total arc of motion (ER + IR), ER, and IR ROM and humeral torsion were calculated as nondominant minus dominant arm measures for analysis. Pitchers were classified as having GIRD if their dominant arm displayed an IR deficit ≥15° concomitant with a total arc of motion deficit ≥10° compared with their nondominant arm. A mixed-model analysis of variance (side × GIRD) was used to compare dominant and nondominant humeral torsion between pitchers with GIRD (n = 60) and those without GIRD (n = 162). Independent t tests were used to compare the side-to-side difference in humeral torsion between pitchers with GIRD and those without GIRD (α = 0.05). Results: Pitchers with GIRD displayed significantly less humeral torsion (ie, greater retrotorsion) in their dominant arm as compared with those without GIRD (GIRD = 4.5° ± 11.8°, no GIRD = 10.4° ± 11.7°; P = .002). Pitchers with GIRD also displayed a greater side-to-side difference in humeral torsion (GIRD = 19.5° ± 11.9°, no GIRD = 12.3° ± 12.4°; P = .001). However, pitchers with GIRD did not display an increase in dominant ER ROM (dominant ER = 131.8° ± 14.3°, nondominant ER 126.6° ± 13.1°) when compared with those without GIRD (dominant ER = 132.0° ± 14.2°, nondominant ER 122.6° ± 13.1°; P = .03). Pitchers with GIRD displayed expected alterations in ROM (IR = 28.8° ± 9.6°, total arc = 160.6° ± 15.4°; P < .01 for both) when compared with those without GIRD (IR = 39.9° ± 9.9°, total arc = 171.2° ± 15.5°). Conclusion: Pitchers with GIRD displayed greater side-to-side differences and dominant humeral retrotorsion as compared with those without GIRD. The greater humeral retrotorsion may place greater stress on the posterior shoulder resulting in ROM deficits. Pitchers with greater humeral retrotorsion appear to be more susceptible to developing ROM deficits associated with injury and may need increased monitoring and customized treatment programs to mitigate their increased injury risk.

Current Rehabilitation Applications for Shoulder Ultrasound Imaging

SYNOPSIS The available body of knowledge on shoulder ultrasound imaging has grown considerably within the past decade, and physical therapists are among the many health care professions currently exploring the potential clinical integration of this imaging technology and the knowledge derived from it. Therefore, the primary purpose of this commentary was to review the recent evidence and emerging uses of ultrasound imaging for the clinical evaluation of shoulder disorders. This includes a detailed description of common measurement techniques along with their known clinimetric properties. Specifically provided are critical appraisals of the existing measures used to estimate soft tissue and bony morphometry, muscle contractile states, and lean muscle density. These appraisals are intended to help clinicians clarify the scope of physical therapy practice for which these measurement techniques are effectively utilized and to highlight areas in need of further development.

Mechanisms of Shoulder Range of Motion Deficits in Asymptomatic Baseball Players

Background: Shoulder range of motion (ROM) deficits have been identified as injury risk factors among baseball athletes. Despite the knowledge surrounding these risk factors, there is a lack of consensus regarding the specific tissues responsible for these deficits in ROM. Purpose/Hypothesis: The purpose of this study was to elucidate the primary mechanisms of posterior shoulder tightness (capsular, musculotendinous, bony) by examining the tissue responses that occur with the application of an acute intervention in baseball players with ROM deficits. The hypothesis was that posterior rotator cuff stiffness, not glenohumeral joint mobility, would be primarily responsible for ROM gains observed within an acute treatment setting. Study Design: Controlled laboratory study. Methods: Through use of ultrasound elastography, electromagnetic motion analysis, and ultrasound imaging, posterior rotator cuff stiffness, glenohumeral joint translation, and humeral torsion were examined in 60 asymptomatic baseball players (age, mean ± SD, 19 ± 2 years) with shoulder ROM deficits. Tissue mechanisms were examined concurrently, with the ROM gains elicited by an acute application of instrument-assisted soft tissue mobilization plus self-stretching (n = 30) versus self-stretching only (n = 30). Separate 3-way analyses of variance (group × arm × time) and linear regression analyses were used to determine the treatment effects and relationships between tissue mechanisms and ROM gains. Results: ROM gains were associated with decreases in rotator cuff stiffness (internal rotation: r = 0.35, P = .034; horizontal adduction: r = 0.44, P = .008) and increased humeral retrotorsion (internal rotation: r = −0.35, P = .034), not joint translation (P > .05). Players receiving instrument-assisted soft tissue mobilization plus stretching displayed greater shoulder ROM gains (internal rotation, +5° ± 2° [P = .010]; total arc of motion, +8° ± 6° [P = .010]; horizontal adduction, +7° ± 2° [P = .004]; and decreased posterior rotator cuff stiffness, −0.2 ± 0.3 kPa [P = .050]) compared with players receiving self-stretching alone. Conclusion: Decreases in rotator cuff stiffness were associated with acute ROM gains in baseball players. The study results show that changes in rotator cuff stiffness, not glenohumeral joint mobility or humeral torsion, are most likely associated with the ROM deficits observed in adolescent baseball players. Clinical Relevance: Reducing rotator cuff stiffness may be beneficial in improving the ROM deficits associated with injury risk in overhead athletes.

Humeral Torsion as a Risk Factor for Shoulder and Elbow Injury in Professional Baseball Pitchers

Background: Numerous studies have demonstrated that humeral retrotorsion is increased in the dominant arms of throwing athletes. No study has clearly defined the relationship between humeral retrotorsion and shoulder and elbow injury. Hypothesis: Uninjured professional pitchers will display more dominant humeral torsion (HT) than professional pitchers who sustain shoulder injuries but less than pitchers who sustain elbow injuries. Study Design: Case-control study; Level of evidence, 3. Methods: Pitchers from the Colorado Rockies professional baseball organization were recruited for participation for this prospective injury study from 2009 to 2013. HT was assessed using indirect ultrasonographic techniques and was measured prospectively in 255 pitchers before each spring training (average of 2 trials). From the beginning of the preseason to the end of the postseason, overuse upper extremity injuries (shoulder or elbow) were tracked for each participating athlete. All athletes who reported pain or injury to their coach were referred to the organization’s athletic trainer for evaluation and classification of each injury. The difference in HT was calculated by subtracting measurement of the dominant arm from the nondominant arm, and 3 separate mixed-model analyses of variance (side × injury group) were used to compare the dominant and nondominant HT between all pitchers who developed an arm injury (shoulder and elbow combined), as well as comparing pitchers who developed a shoulder or elbow injury to those who did not miss games due to shoulder or elbow injury (α = .05). Results: During the course of the study, 60 arm (30 shoulder; 30 elbow) injuries were observed; 195 pitchers did not suffer an injury. There were no differences when HT was compared between all injured (shoulder and elbow injuries combined) and uninjured pitchers (P = .13; effect size 0.14). There was a significant interaction effect showing that pitchers who suffered a shoulder injury displayed 4° less dominant humeral retrotorsion compared with pitchers without injury (P = .04) and that pitchers with elbow injury displayed 5° greater humeral retrotorsion (P = .04). In addition, those who suffered an ulnar collateral ligament injury requiring reconstruction (n = 17) also displayed 4o greater dominant retrotorsion and 5° less nondominant humeral retrotorsion compared with pitchers who did not suffer an injury (n = 195; P = .05). There was not a significant difference between nondominant HT among pitchers who sustained shoulder and elbow injuries and pitchers without injury. Conclusion: The results of this study show a contrast in dominant humeral retrotorsion between pitchers who suffered shoulder and elbow injuries compared with those without an injury. Pitchers who sustained shoulder injuries had less dominant humeral retrotorsion compared with noninjured pitchers. In contrast, pitchers who sustained time-loss elbow injuries displayed increased humeral retrotorsion compared with noninjured pitchers. Together, these results suggest that increased adaptive humeral retrotorsion is protective against shoulder injuries but a harmful contributor for elbow injuries in professional pitchers. This is the first study to show differing injury risk profiles for shoulder and elbow injury.

Functional bracing after anterior cruciate ligament reconstruction: A systematic review

Introduction: The purpose of this study was to evaluate the current literature on the use of functional knee braces after anterior cruciate ligament (ACL) reconstruction with respect to clinical and in vivo biomechanical data. Methods: A systematic search of both the PubMed and Embase databases was performed to identify all studies that reported clinical and/or in vivo biomechanical results of functional bracing versus nonbracing after ACL reconstruction. Extracted data included study design, surgical reconstruction techniques, postoperative rehabilitation protocols, objective outcomes, and subjective outcomes scores. The in vivo biomechanical data collected included kinematics, strength, function, and proprioception. Subjective clinical outcomes scores were collected when available. Quality appraisal analyses were performed using the Cochrane Collaboration tools for randomized and nonrandomized trials to aid in data interpretation. Results: Fifteen studies met the selection criteria (including 3 randomized trials [level II], 11 nonrandomized trials [level II], and 1 retrospective comparative study [level III]), with follow-up intervals ranging from 3 to 48 months. Most studies were designed to compare the effects of functional bracing versus nonbracing on subjective and objective results in patients who underwent previous primary ACL reconstruction. Functional bracing significantly improved kinematics of the knee joint and improved gait kinetics, although functional bracing may decrease quadriceps activation without affecting functional tests, range of motion, and proprioception. Four studies reported no differences in subjective outcomes scores with brace use; however, one study reported increased patient confidence with brace use, whereas another study reported decreased pain and quicker return to work when the brace was not used. Conclusions: The effectiveness of postoperative functional bracing following ACL reconstruction remains elusive. Some data suggest that functional bracing may have some benefit with regard to in vivo knee kinematics and may offer increased protection of the implanted graft after ACL reconstruction without sacrificing function, range of motion, or proprioception. However, limited evidence exists supporting the use of routine functional bracing to decrease the rate of reinjury after ACL reconstruction.

Preoperative Ultrasonography Is Unreliable in Predicting Hamstring Tendon Graft Diameter for ACL Reconstruction

Background: Hamstring autograft size <8 mm has been shown to be a predictor for failure after anterior cruciate ligament (ACL) reconstruction. The ability to predict graft size preoperatively is helpful in counseling patients about the possible need for graft augmentation. Purpose: To determine whether preoperative ultrasound (US) measurements of hamstring tendons can predict intraoperative graft diameter during ACL reconstruction. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Twenty patients undergoing unilateral isolated ACL reconstruction were prospectively enrolled in the study (10 males, 10 females; mean ± SD age, 22.8 ± 6.6 years; height, 175.1 ± 7.1 cm; weight, 81.4 ± 14.2 kg; body mass index, 26.5 ± 4.1 kg/m2). Hamstrings were assessed by US, and double-looped semitendinosus-gracilis hamstring size was independently calculated with a freehand selection method on a nonmagnified US image by 2 orthopaedic surgeons. Intraoperative autograft size was determined with a standard graft-sizing tool. Intra- and interrater reliability was measured with intraclass correlation coefficients (ICCs) and standard error of the measure (SEM). A receiver operating characteristic curve was calculated to assess the ability of the US measurement to predict intraoperative measurements. Results: The mean autograft diameter by US was 8.9 ± 0.98 mm, while the mean intraoperative hamstring graft size was 8.1 ± 0.89 mm. There was excellent intrarater (ICC2,1 = 0.95, SEM = 0.32 mm) and interrater (ICC2,1 = 0.88, SEM = 0.55 mm) reliability for US measurements. Receiver operating characteristic analysis showed that US did not consistently quantify graft size. Graft size did not significantly correlate with height, weight, or body mass index in our sample (P > .05). Conclusion: These results suggest that preoperative US imaging of the hamstring tendons is unreliable in predicting intraoperative graft diameter.

The use of a pitch count estimator to calculate exposure in collegiate baseball pitchers

OBJECTIVE Excessive pitch counts have been associated with arm pain in pitchers. Tracking of exposure is difficult based on participation on multiple teams and variability in organizational rules. Statisticians have estimated exposure for professional pitchers using pitch count estimators. Our objective was to determine the utility of pitch count estimators at the collegiate level. DESIGN AND PARTICIPANTS Cohort; 29 collegiate pitchers. METHODS The team athletic trainer collected game pitch count data. The total number of batters faced (PA), strike outs (SO), and walks (BB) were recorded from the box score and entered into the pitch count formula (3.3*PA + 1.5*SO + 2.2*BB) to estimate pitch counts. Intraclass correlation coefficients (ICCs(2,1)) and standard error of measurement (SEM), were used to examine the agreement between actual and estimated pitch counts. RESULTS The mean pitch count was correlated with the estimated pitch count (628 ± 476 vs.603 ± 426; r = .99, p < .001). The actual and estimated pitch counts per season demonstrated excellent agreement (ICC(2,1) = 0.99; SEM = 56 pitches). The ICC(2,1) calculated to compare actual and estimated pitch counts for starters and relievers (ICC(2,1) = 0.98; SEM = 77; 0.98; SEM = 39) reflect good agreement. CONCLUSIONS The estimator provides a method of quantifying exposure for pitchers to help plan safe participation and control for confounding factors when attempting to understand the risks of pitching.

Predictive Risk of Ulnar Collateral Ligament Injury Based on Ligament Morphology and Dynamic Abnormalities in Professional Baseball Pitchers Using Stress Ultrasonography

Objectives: Ulnar collateral ligament (UCL) injury of the elbow is a common and debilitating problem seen frequently in elite baseball pitchers. Ultrasound has been shown to be a useful diagnostic tool in evaluating UCL injuries. We hypothesized that the evaluation using stress ultrasound (US) of the elbow to measure both the morphology of the UCL and the ulnohumeral joint space gapping as a surrogate for UCL incompetence will be helpful to predict UCL injury in professional baseball pitchers. Methods: Ultrasound imaging was used to assess the medial joint laxity of both arms of 70 asymptomatic professional baseball pitchers during spring training. Medial joint laxity and UCL morphology was assessed using OsiriX Imaging Software under 2 conditions: (1) gravity valgus load and (2) 10 lbs of valgus load using a handheld dynamometer with the shoulder in the maximal cocking position and the elbow in 90° of flexion. Two trials of resting position, elbow gapping, and UCL thickness were collected, measured and averaged for data analysis. Intra and inter rater reliability was established and maintained with ICCs in the acceptable range for all measures (.84-.99). One-way ANOVA (α=0.05) was used to compare pitchers’ dominant variables between those with a prospective UCL injury to those who never had a UCL injury. Receiver Operating Curve (ROC) was used to identify pitchers who, based on elbow gapping measures (by cut score), were at high-risk versus those at low risk for UCL injury. (AUC > .70; α=0.05). Results: Players with a prospective UCL injury (n=7) presented with a trend toward wider (mm) D arm resting joint opening (4.9± 1.2 vs. 4.0±1.1; p=0.07), significantly wider gapped opening (6.5± 1.2 vs. 5.3 ± 1.2; p=0.01) and greater peak stiffness (nm) (.17±.09 vs. 10 ±.07; p=0.03) when compared to pitchers without UCL injury history (n=63). Figure 1 displays larger values of dynamic elbow gapping differentiated between UCL injured (>5.5 mm) and uninjured pitchers (AUC=0.77; p=0.02). Conclusion: Our data suggests that changes present in the UCL and detectable on ultrasound may help distinguish elbows at risk for later clinical UCL insufficiency. Screening using ultrasound of UCL thickness, loaded joint gapping, and stiffness may help predict the likelihood of elbow injury in professional baseball pitchers.

Influence of a Prevention Program on Arm Injury Risk: An RCT in Adolescent Pitchers

Objectives: High school pitchers are at three times greater risk of an upper extremity (UE) injury compared to position players, with most (69%) injuries occurring during the first month of the season. Therefore, a prevention program for pitchers targeting known risk factors may reduce their injury risk, particularly early in the season. The purpose of this study was to determine the effectiveness of a preseason training program in decreasing the injury rate and altering the pattern of UE injuries in a cohort of high school pitchers. Methods: Healthy high school pitchers (n=196) who were participating in all team activities were block randomized by school to intervention (INV, n=103) or control (CON, n=93) groups. The INV group received a scapular stability, rotator cuff strength, and posterior shoulder flexibility program (3 times/week for 8 consecutive weeks) supervised by an Athletic Trainer. The CON group participated in the teams’ usual preseason training. Training activities for all teams were recorded. All players participated in a 4-week interval-throwing program. Athletic exposures (AEs), injury incidence (participation absence or limitation due to injury) were tracked from the first day of practice until the last day of competition. Incidence rates were calculated per 1,000 AEs and monthly trends for injury were examined for occurrence by group, injury history, and body location. As a secondary analysis, published injury rates from 2009 in the same high schools were compared to their 2012 data. Rate ratios (RR) and 95% confidence intervals (CIs) were used to compare injury rates by group, injury history, body location, and year. Results: Overall, there were 27 UE injuries incurred among the pitchers; 15 in the INT group (10 shoulder & 5 elbow injuries) and 12 in the CON group (10 shoulder & 2 elbow injuries). The injury rate was similar in the INT and CON groups (RR=0.86; 95% CI: 0.43-2.2). The pattern of arm injuries throughout the season was evenly distributed in both groups. In 2012, 67% of CON teams were observed participating in a general “arm care” program as compared to 6% of CON teams in 2009. Previous arm injury did not increase the risk of an UE injury in the INV group (RR=1.0; 95% CI: 0.38-2.8) but did increase the risk of an UE injury almost 4-fold (RR= 3.7,95% CI: 1.3-10.7) in the CON group. The injury incidence rate for pitchers was 12 times higher in 2009 (29.3/1,000 AEs) than in 2012 (3.4/1,000 AEs) (RR=11.6, 95% CI: 7.1-16.1). The risks of shoulder (RR=11.0; 95% CI: 6.6-15.4) and elbow injury (RR=12.6; 95% CI: 8.0-17.3) were higher in 2009 compared to 2012. The pattern of upper extremity injuries was higher in the first quarter of the season compared to 2012 (See Figure 1). Conclusion: The main finding of this study is that INV and CON pitchers had a similar injury rate, however, the overall injury rates were significantly lower in 2012 than in 2009. Thus it appears that a general “arm care” and interval-throwing program may also be effective in reducing the injury rate in high school pitchers, perhaps in the early part of the season as injury rates based on the differences in rates between 2012 and 2009. Pitchers with a previous injury in the INV group were less likely to suffer an injury in 2012 than pitchers’ with a previous injury in the CON group. Thus, a targeted pre-season conditioning program may help reduce the injury risk in pitchers with a history of of previous arm injury. Further studies are warranted to confirm our results.