Unaccounted for Pitch Volume Among Adolescent Baseball Pitchers During a Travel Baseball Season.

OBJECTIVE: The primary aim was to compare differences in live game pitch counts (LGPCs) with all pitch counts (APCs) over the course of a youth baseball season. DESIGN: Prospective longitudinal study. SETTING: Midwest youth travel baseball. PARTICIPANTS: Ten male baseball players part of a youth baseball travel team. VARIABLES: Demographic data, pitch counts (practice, game, warm-up, and bullpen), innings pitched, and recommended rest days. MAIN OUTCOME MEASURES: Live pitch counts compared with APCs and the relationship to recommended rest days. RESULTS: During the season, 7866 pitches were recorded among 9 pitchers. By using the LGPC method alone, 42.5% of the pitches were unaccounted for. When considering age-specific rest days suggested by Pitch Smart Guidelines (PSGs), there were 104 rest days unaccounted for by using the live game pitch method. CONCLUSION: There is a high number of unaccounted for pitches and an underestimation of rest days per outing when using live game methods. Revisions to the PSGs that include all pitches should be considered to accurately reflect pitching volume, which may be associated with the rising rate of injuries among these athletes.

Impacts of educational debt on physical therapist employment trends.

BACKGROUND: Newly graduated physical therapists have high amounts of educational debt. Educational debt may negatively affect job satisfaction, aspirations for professional development, and choice of workplace setting. Research has not shown this association directly, yet it is conceptually supported by the Labor-Search Model. The purpose of this study was to understand the role that educational debt has on additional factors related to job choice in the Labor-Search Model. METHODS: Retrospective data were captured through the Virginia Longitudinal Data System (VLDS) for 12,594 licensed physical therapists within the Commonwealth of Virginia from 2014 to 2020. A fixed effects panel analysis, with inflation-adjusted educational debt as the variable of interest, was conducted to assess whether patterns of professional certifications, volume of work, workplace setting, and job satisfaction were related to educational debt. RESULTS: Educational debt was positively correlated with higher professional degrees (p = 0.009), the number of hours worked per week (p = 0.049), and expected number of years until retirement (p = 0.013). Job satisfaction was statistically significant (p = 0.042) and negatively correlated with educational debt. CONCLUSIONS: Those with higher educational debt appear to have the habit of working more hours per week and have a longer time horizon until retirement. Newly licensed physical therapists with higher amounts of educational debt are more likely to experience this trend. Income and job satisfaction demonstrated an interaction effect on educational debt, such that those with lower levels of income had a stronger, negative relationship between their debt and job satisfaction, as compared to those with higher income.

External Match Load in Women's Collegiate Lacrosse.

ABSTRACT: Devine, NF, Hegedus, EJ, Nguyen, A-D, Ford, KR, and Taylor, JB. External match load in women's collegiate lacrosse. J Strength Cond Res 36(2): 503-507, 2022-Quantifying external loads during athletic activities, particularly game-level competition, can provide objective data for the management of athlete performance, late-stage rehabilitation, and return-to-play decisions after lower extremity injury; yet, no studies have quantified these data in collegiate women's lacrosse athletes. The purpose of this study was to report external load values for collegiate women's lacrosse players and identify positional differences in activity demands during game competition. Load data were collected on 18 collegiate women's lacrosse players using a wearable global positioning system unit during a 19-game season. Descriptive statistics of distance, speed, and frequency (sprints, high-intensity sprints, high-intensity accelerations, high-intensity decelerations) measures were computed. Linear mixed models were used to identify differences between positions and phases of the season (α = 0.05). On average, players travelled 4,733 ± 2,294 m per game (range, 1,259-7,811 m), of which 656 ± 446 m (range 60-1,633 m) occurred at high-intensity speeds and reached a maximum speed of 24.1 ± 2.6 km·h-1 (range, 19.2-27.7 km·h-1). In each game, subjects averaged 124 ± 68 sprints, 6.1 ± 4.1 high-intensity sprints, 51 ± 34 high-intensity accelerations, and 38 ± 25 high-intensity decelerations. Positional differences were identified for total (p = 0.04) and relative (p = 0.01) distance travelled at high-intensity speeds, and frequency of sprints (p = 0.01) and high-intensity decelerations (p = 0.03). During game competition, collegiate women's lacrosse demands significant external load, much of which occurs at high intensities. These data provide sport- and position-specific values for reference during late-stage rehabilitation and return-to-play testing, allowing clinicians to quantitatively progress load tolerance throughout rehabilitation and guide safe return to play.

The reliability, validity, and methodologic quality of measurements used to quantify posterior shoulder tightness: a systematic review of the literature with meta-analysis.

HYPOTHESIS AND BACKGROUND: Posterior shoulder tightness (PST) has been linked to numerous shoulder pathologies in both the general and athletic populations. Several methods for documenting PST have been described in the literature, which may lend to variability in clinical practice and research. The purpose of this study was to perform a systematic review with meta-analysis to investigate the reliability, validity, and methodologic quality of methods used to quantify PST. METHODS: Relevant studies were assessed for inclusion, and selected studies were identified from the PubMed, Embase, Cochrane, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) databases. Data were extracted from the selected studies and underwent methodologic quality assessment and meta-analysis. RESULTS: The search resulted in 1006 studies identified, with 18 ultimately retained. Intrarater reliability was reported in 12 studies with a summary intraclass correlation coefficient of 0.93 (95% confidence interval, 0.90-0.95), whereas inter-rater reliability was reported in 6 studies with a summary intraclass correlation coefficient of 0.89 (95% confidence interval, 0.80-0.94). Validity was reported in 10 studies, all using internal rotation as the convergent standard, and was found to be significant in all but 1 study. CONCLUSION: Current methods used to quantify PST have good reliability but are primarily limited to measures of horizontal adduction of the glenohumeral joint with scapular stabilization. Limitations in using a single measurement technique exist particularly as there may be multiple contributing factors to PST. A more comprehensive approach for quantifying PST is necessary, and suggested components include a cluster of techniques composed of horizontal adduction, internal rotation, and total glenohumeral joint range of motion.

Exercise prescription for overhead athletes with shoulder pathology: a systematic review with best evidence synthesis.

OBJECTIVE: To produce a best evidence synthesis of exercise prescription used when treating shoulder pathology in the overhead athlete. DESIGN: A systematic review of exercises used in overhead athletes including case studies and clinical commentaries. DATA SOURCES: MEDLINE, PubMed, SPORTDiscus and CINAHL from database inception through July 8, 2016. METHODS: We examined data from randomised controlled trials and prospective cohort (level I-IV evidence) studies that addressed exercise intervention in the rehabilitation of the overhead athlete with shoulder pathology. Case studies and clinical commentaries (level V evidence) were examined to account for expert opinion-based research. Data were combined using best evidence synthesis and graded (A-F) recommendations (Centre for Evidence-Based Medicine). RESULTS: There were 33 unique exercises in six level I-IV studies that met our inclusion criteria. Most exercises were single-plane, upper extremity exercises performed below 90o of elevation. There were 102 unique exercises in 33 level V studies that met our inclusion criteria. These exercises emphasised plyometrics, kinetic chain and sport-specific training. CONCLUSIONS AND RELEVANCE: Overall, evidence for exercise interventions in overhead athletes with shoulder pathology is dominated by expert opinion (grade D). There is great variability between exercise approaches suggested by experts and those investigated in research studies and the overall level of evidence is low. The strongest available evidence (level B) supports the use of single-plane, open chain upper extremity exercises performed below 90° of elevation and closed chain upper extremity exercises. Clinical expert pieces support a more advanced, global treatment approach consistent with the complex, multidimensional nature of sport.

Vertical Jump Biomechanics Altered With Virtual Overhead Goal.

Virtual environments with real-time feedback can simulate extrinsic goals that mimic real life conditions. The purpose was to compare jump performance and biomechanics with a physical overhead goal (POG) and with a virtual overhead goal (VOG). Fourteen female subjects participated (age: 18.8 ± 1.1 years, height: 163.2 ± 8.1 cm, weight 63.0 ± 7.9 kg). Sagittal plane trunk, hip, and knee biomechanics were calculated during the landing and take-off phases of drop vertical jump with different goal conditions. Repeated-measures ANOVAs determined differences between goal conditions. Vertical jump height displacement was not different during VOG compared with POG. Greater hip extensor moment (P < .001*) and hip angular impulse (P < .004*) were found during VOG compared with POG. Subjects landed more erect with less magnitude of trunk flexion (P = .002*) during POG compared with VOG. A virtual target can optimize jump height and promote increased hip moments and trunk flexion. This may be a useful alternative to physical targets to improve performance during certain biomechanical testing, screening, and training conditions.

Clinician-friendly physical performance tests in athletes part 3: a systematic review of measurement properties and correlations to injury for tests in the upper extremity.

OBJECTIVE: In parts 1 and 2 of this systematic review, the methodological quality as well as the quality of the measurement properties of physical performance tests (PPTs) of the lower extremity in athletes was assessed. In this study, part 3, PPTs of the upper extremity in athletes are examined. METHODS: Database and hand searches were conducted to identify primary literature addressing the use of upper extremity PPTs in athletes. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed and the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist was used to critique the methodological quality of each paper. The Terwee Scale was used to analyse the quality of the measurement properties of each test. RESULTS: 11 articles that examined 6 PPTs were identified. The 6 PPTs were: closed kinetic chain upper extremity stability test (CKCUEST), seated shot put (2 hands), unilateral seated shot put, medicine ball throw, modified push-up test and 1-arm hop test. Best evidence synthesis provided moderate positive evidence for the CKCUEST and unilateral seated shot put. Limited positive evidence was available for the medicine ball throw and 1-arm hop test. CONCLUSIONS: There are a limited number of upper extremity PPTs used as part of musculoskeletal screening examinations, or as outcome measures in athletic populations. The CKCUEST and unilateral seated shot put are 2 promising PPTs based on moderate evidence. However, the utility of the PPTs in injured populations is unsubstantiated in literature and warrants further investigation.

Physical performance tests predict injury in National Collegiate Athletic Association athletes: a three-season prospective cohort study.

BACKGROUND: The ability to predict injury is difficult. Prior injury is the only risk factor that has been reported consistently in multiple research studies. Convenient and easy to perform, physical performance tests (PPTs) have great allure as prognostic factors. METHODS: 11 PPTs were issued to 359 participants over the course of three seasons of National Collegiate Athletic Association Division I athletic competition. Injuries were monitored and reported in a centralised university tracking system. Exploratory factor analysis was performed in order to group the PPTs into constructs. The relationship between injury and these PPT-based constructs and other known predictors of injury was explored using univariate and multivariate regression. RESULTS: PPTs clustered into five constructs: (1) active motion, (2) power, (3) hip stability, (4) flexibility and (5) motor control. When these five were placed into a multiple regression equation along with known risk factors (age, body mass index (BMI), gender, excessive flexibility and past injury), hip stability and active motion were predicted injury. In addition, motor control predicted non-traumatic injury. Past injury did not predict injury in the multivariate model. SUMMARY: In college athletes, hip stability, active motion and motor control as assessed through PPTs can be useful as part of preseason screening. These PPT-related constructs seem to have a mediating effect on the relationship between past injury and future injury. This study provides the rationale to test targeted interventions to address these limitations. CLINICAL TRIAL REGISTRATION NUMBER: NCT01804894.

Assessments of Fatty Infiltration and Muscle Atrophy From a Single Magnetic Resonance Image Slice Are Not Predictive of 3-Dimensional Measurements.

PURPOSE: To (1) determine whether standard clinical muscle fatty infiltration and atrophy assessment techniques using a single image slice for patients with a rotator cuff tear (RCT) are correlated with 3-dimensional measures in older individuals (60+ years) and (2) to determine whether age-associated changes to muscle morphology and strength are compounded by an RCT. METHODS: Twenty older individuals were studied: 10 with an RCT of the supraspinatus (5 men and 5 women) and 10 matched controls. Clinical imaging assessments (Goutallier and Fuchs scores and cross-sectional area ratio) were performed for participants with RCTs. Three-dimensional measurements of rotator cuff muscle and fat tissues were obtained for all participants using magnetic resonance imaging (MRI). Isometric joint moment was measured at the shoulder. RESULTS: There were no significant associations between single-image assessments and 3-dimensional measurements of fatty infiltration for the supraspinatus and infraspinatus muscles. Compared with controls, participants with RCTs had significantly increased percentages of fatty infiltration for each rotator cuff muscle (all P ≤ .023); reduced whole muscle volume for the supraspinatus, infraspinatus, and subscapularis muscles (all P ≤ .038); and reduced fat-free muscle volume for the supraspinatus, infraspinatus, and subscapularis muscles (all P ≤ .027). Only the teres minor (P = .017) fatty infiltration volume was significantly greater for participants with RCTs. Adduction, flexion, and external rotation strength (all P ≤ .021) were significantly reduced for participants with RCTs, and muscle volume was a significant predictor of strength for all comparisons. CONCLUSIONS: Clinical scores using a single image slice do not represent 3-dimensional muscle measurements. Efficient methods are needed to more effectively capture 3-dimensional information for clinical applications. Participants with RCTs had increased fatty infiltration percentages that were likely driven by muscle atrophy rather than increased fat volume. The significant association of muscle volume with strength production suggests that treatments to preserve muscle volume should be pursued for older patients with RCTs. LEVEL OF EVIDENCE: Level II, diagnostic study, with development of diagnostic criteria on the basis of consecutive patients with universally applied reference gold standard.

Upper-Extremity Physical-Performance Tests in College Athletes.

CONTEXT: Physical-performance tests (PPTs) are commonly used in rehabilitation and injury-prevention settings, yet normative values of upper-extremity PPTs have not been established in high-level athletes. OBJECTIVE: To establish normative data values for the Closed Kinetic Chain Upper-Extremity Stability Test (CKCUEST) and Upper-Quarter Y-Balance Test (UQYBT) in college athletes and compare results between sports and to analyze the relationship between the 2 tests. DESIGN: Observational. SETTING: Laboratory/athletic facility. PARTICIPANTS: 257 (118 male, 139 female) Division I athletes participating in basketball, soccer, baseball, lacrosse, volleyball, track and field, and cross-country. INTERVENTION: CKCUEST and UQYBT scores were recorded as part of a comprehensive injury-risk screening battery. MAIN OUTCOME MEASURE: Pearson correlations assessed the relationship between all measures of the CKCUEST and UQYBT. A factorial ANOVA and a repeated-measures ANOVA (arm dominance) were used to assess interactions between sex, year in school, and sport for CKCUEST and UQYBT scores. RESULTS: Normative values for the CKCUEST and UQYBT were established for 9 men's and women's college sports. No significant relationships were found between PPT scores. Men scored significantly higher than women for the CKCUEST (P = .002) and UQYBT (P = .010). Baseball players scored significantly higher than athletes from all other sports for the UQYBT (P < .001) but showed nonsignificant trends of lower scores for the CKCUEST than lower-extremity-dominant athletes such as runners (P = .063) and lacrosse players (P = .058). CONCLUSIONS: Results suggest that average CKCUEST and UQYBT scores in Division I athletes are distinct from those previously reported in recreationally active populations and that performance differences exist between sexes and sports. In addition, the CKCUEST and UQYBT appear to measure different constructs of performance and may complement each other as part of a screening battery.

Clinician-friendly lower extremity physical performance measures in athletes: a systematic review of measurement properties and correlation with injury, part 1. The tests for knee function including the hop tests.

OBJECTIVE: To review the measurement properties of physical performance tests (PPTs) of the knee as each pertain to athletes, and to determine the relationship between PPTs and injury in athletes age 12 years to adult. METHODS: A search strategy was constructed by combining the terms 'lower extremity' and synonyms for 'performance test', and names of performance tests with variants of the term 'athlete'. In this, part 1, we report on findings in the knee. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were followed and the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist was used to critique the methodological quality of each paper. A second measure was used to analyse the quality of the measurement properties of each test. RESULTS: In the final analysis, we found 29 articles pertinent to the knee detailing 19 PPTs, of which six were compiled in a best evidence synthesis. The six tests were: one leg hop for distance (single and triple hop), 6 m timed hop, crossover hop for distance, triple jump and single leg vertical jump. The one leg hop for distance is the most often studied PPT. There is conflicting evidence regarding the validity of the hop and moderate evidence that the hop test is responsive to changes during rehabilitation. No test has established reliability or measurement error as assessed by the minimal important change or smallest detectable change. No test predicts knee injury in athletes. CONCLUSIONS: Despite numerous published articles addressing PPTs at the knee, there is predominantly limited and conflicting evidence regarding the reliability, agreement, construct validity, criterion validity and responsiveness of commonly used PPTs. There is a great opportunity for further study of these tests and the measurement properties of each in athletes.

Clinician-friendly lower extremity physical performance tests in athletes: a systematic review of measurement properties and correlation with injury. Part 2--the tests for the hip, thigh, foot and ankle including the star excursion balance test.

OBJECTIVE: To review the quality of literature and measurement properties of physical performance tests (PPTs) of the lower extremity in athletes. METHODS: Using the PICOS method we established our research question as to whether individual PPTs of the lower extremity have any relationship to injury in competitive athletes ages 12 years to adult (no limit). A search strategy was constructed by combining the terms 'lower extremity' and synonyms for 'performance test' and names of performance tests with variants of the term 'athlete'. After examining the knee in part 1 of this 2 part series, the current report focuses on findings in the rest of the lower extremity. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed and the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist was used to critique the methodological quality of each paper. A second measure was used to analyse the quality of the measurement properties of each test. RESULTS: Thirty-one articles examined the measurement properties of 14 PPTs pertaining to the lower extremity. The terminology used to name and describe the tests and methodology by which the tests were conducted was inconsistent. The star excursion balance test performed in three directions (anterior, posteromedial, and posterolateral) appears to be the only test to be associated with increased injury risk. There is moderate evidence that the one leg hop for distance and the hexagon hop can distinguish between normal and unstable ankles. There is also moderate evidence that the medial hop can distinguish between painful and normal hips in dancers. CONCLUSIONS: Currently, there is relatively limited research-backed information on PPTs of the lower extremity in athletes. We would suggest convening an international consortium comprised of experts in sports to standardise the descriptions and methodologies, and to set forth a research agenda to establish definitively the measurement properties of the most common PPTs.

Stress Drives Soccer Athletes' Wellness and Movement: Using Convergent Cross-Mapping to Identify Causal Relationships in a Dynamic Environment.

PURPOSE: Prediction of athlete wellness is difficult-or, many sports-medicine practitioners and scientists would argue, impossible. Instead, one settles for correlational relationships of variables gathered at fixed moments in time. The issue may be an inherent mismatch between usual methods of data collection and analysis and the complex nature of the variables governing athlete wellness. Variables such as external load, stress, muscle soreness, and sleep quality may affect each other and wellness in a dynamic, nonlinear, way over time. In such an environment, traditional data-collection methods and statistics will fail to capture causal effects. If we are to move this area of sport science forward, a different approach is required. METHODS: We analyzed data from 2 different soccer teams that showed no significance between player load and wellness or among individual measures of wellness. Our analysis used methods of attractor reconstruction to examine possible causal relationships between GPS/accelerometer-measured external training load and wellness variables. RESULTS: Our analysis showed that player self-rated stress, a component of wellness, seems a fundamental driving variable. The influence of stress is so great that stress can predict other components of athlete wellness, and, in turn, self-rated stress can be predicted by observing a player's load data. CONCLUSION: We demonstrate the ability of nonlinear methods to identify interactions between and among variables to predict future athlete stress. These relationships are indicative of the causal relationships playing out in athlete wellness over the course of a soccer season.

Identification of cut-points in commonly used hip osteoarthritis-related outcome measures that define the patient acceptable symptom state (PASS).

To determine patient acceptable symptom state (PASS) estimates in outcome measures commonly used in hip osteoarthritis (OA). Identification of cut-points on commonly used outcome measures associated with patient satisfaction with their current state of health. As part of a randomized controlled trial, 70 patients with a clinical diagnosis of hip OA undergoing a 9-session physiotherapy treatment program completed four physical performance measures and three self-report measures at 9 weeks and 1 year. Upon completion of treatment, patients assessed their current health status according to the PASS question. Cut-points were estimated using receiver operating characteristic curves (anchor-based method), based on the patient's response to the PASS question. At 9 weeks and 1 year, identified cut-points were, respectively, ≤10 and ≤11 for the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale; ≤35 and ≤40 on the WOMAC physical function subscale; ≥+5 and ≥+6 on the global rating of change score; ≤6.05 and ≤5.30 s for the timed-up-and-go; ≤28.3 and ≤24.9 for the 40-m self-paced walk test; ≥11 and ≥12 repetitions for the 30-s chair stand test; and ≥46 repetitions for the 20-cm step test. Initial target cut-points signaling patient satisfaction with their current symptom state following physiotherapy in patients with hip osteoarthritis were determined for seven outcome measures over 1 year.

A user's guide to performance of the best shoulder physical examination tests.

BACKGROUND: This article provides clinicians with a user's guide on the performance of the shoulder physical examination tests most supported by current evidence from a recent systematic review published in the British Journal of Sports Medicine. DISCUSSION: A description of clinical shoulder tests is provided with explanations on exact testing procedures and complimentary photographs.

Diagnostic accuracy of clinical tests of the hip: a systematic review with meta-analysis.

BACKGROUND: Hip Physical Examination (HPE) tests have long been used to diagnose a myriad of intra-and extra-articular pathologies of the hip joint. Useful clinical utility is necessary to support diagnostic imaging and subsequent surgical decision making. OBJECTIVE: Summarise and evaluate the current research and utility on the diagnostic accuracy of HPE tests for the hip joint germane to sports related injuries and pathology. METHODS: A computer-assisted literature search of MEDLINE, CINHAL and EMBASE databases (January 1966 to January 2012) using keywords related to diagnostic accuracy of the hip joint. This systematic review with meta-analysis utilised the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for the search and reporting phases of the study. Der-Simonian and Laird random effects models were used to summarise sensitivities (SN), specificities (SP), likelihood ratios and diagnostic OR. RESULTS: The employed search strategy revealed 25 potential articles, with 10 demonstrating high quality. Fourteen articles qualified for meta-analysis. The meta-analysis demonstrated that most tests possess weak diagnostic properties with the exception of the patellar-pubic percussion test, which had excellent pooled SN 95 (95% CI 92 to 97%) and good specificity 86 (95% CI 78 to 92%). CONCLUSION: Several studies have investigated pathology in the hip. Few of the current studies are of substantial quality to dictate clinical decision-making. Currently, only the patellar-pubic percussion test is supported by the data as a stand-alone HPE test. Further studies involving high quality designs are needed to fully assess the value of HPE tests for patients with intra- and extra-articular hip dysfunction.

Diagnostic accuracy of scapular physical examination tests for shoulder disorders: a systematic review.

OBJECTIVE: To systematically review and critique the evidence regarding the diagnostic accuracy of physical examination tests for the scapula in patients with shoulder disorders. METHODS: A systematic, computerised literature search of PubMED, EMBASE, CINAHL and the Cochrane Library databases (from database inception through January 2012) using keywords related to diagnostic accuracy of physical examination tests of the scapula. The Quality Assessment of Diagnostic Accuracy Studies tool was used to critique the quality of each paper. RESULTS: Eight articles met the inclusion criteria; three were considered to be of high quality. Of the three high-quality studies, two were in reference to a 'diagnosis' of shoulder pain. Only one high-quality article referenced specific shoulder pathology of acromioclavicular dislocation with reported sensitivity of 71% and 41% for the scapular dyskinesis and SICK scapula test, respectively. CONCLUSIONS: Overall, no physical examination test of the scapula was found to be useful in differentially diagnosing pathologies of the shoulder.

The relative effectiveness of segment specific level and non-specific level spinal joint mobilization on pain and range of motion: results of a systematic review and meta-analysis.

STUDY DESIGN: Systematic literature review and meta-analysis. OBJECTIVE: IN SYMPTOMATIC SUBJECTS TO: (1) examine the effects of a single session of joint mobilization on pain at rest and with most painful movement, and (2) compare the effects when joint mobilization is provided to a specific or non-specific spinal level. BACKGROUND: Joint mobilization is routinely used for treating spinal pain in conjunction with other interventions, but its unique effect is not well understood. Further, there is controversy about the role of 'specific level' techniques in producing benefit. METHODS: Searches were performed for randomized controlled trials (RCTs) using electronic databases (MEDLINE, CINAHL, and PEDro) from 1966 through November 2010. Methodological quality was assessed using previously detailed criteria. Meta-analysis and meta-regression were conducted on eligible studies. RESULTS: Eight RCTs with a mean methodological score of 10/12 were included. Significant heterogeneity (P = 0.075) was found in the overall meta-analysis estimate. When stratified by body location, no significant individual effect was found for pain at rest. However, there was a statistical mean difference [0.71 (95% confidence interval: 0.13-1.28)] between pain at rest for the cervical and lumbar individual means. CONCLUSIONS: We found multiple studies which provided evidence that a single session of joint mobilization can lead to a reduction of pain at rest and with most painful movement. When using joint mobilization, the need for specific versus non-specific level mobilization may be influenced by anatomical region; the direction of effect in the cervical spine was toward specific mobilization and in the lumbar spine towards non-specific mobilization.