Distinctive characteristics of prolonged standing low back pain developers' and the associated risk factors: systematic review and meta-analysis.

Pain developers (PDs) are considered a pre-clinical low back pain (LBP) population at risk of clinical LBP development and thus exacting great social and economic costs. Therefore, it is necessary to comprehensively investigate their distinctive characteristics and the risk factors of standing-induced LBP based on which appropriate preventive measures can be planned. Scopus, Web of Science, and PubMed databases as well as Google Scholar and ProQuest were systematically searched from inception through 14 July 2022 using a combination of terms relevant to 'standing' and 'LBP'. Studies with low risk of bias in English and Persian using a methodological quality scoring system were deemed eligible for inclusion if they were laboratory studies using prolonged standing duration greater than 42 min to classify adult PDs and non-pain developers (NPDs) without a history of LBP. PDs were compared with NPDs in demographics, biomechanical, and psychological outcomes. Weighted or standardized mean differences, and Hedge's g were generated to determine the pooled effect sizes using STATA software version 17. 52 papers and theses involving 1070 participants (528 PDs and 542 NPDs) were eligible for inclusion in the systematic review 33 of which were used in meta-analyses. Significant differences between PDs and NPDs in terms of movement patterns, muscular, postural, psychological, structural, and anthropometric variables were evidenced. The following factors were found to have a statistically significant association with standing-induced LBP: lumbar fidgets (Hedge's g - 0.72, 95% CI - 1.35 to - 0.08, P = 0.03), lumbar lordosis in participants over 25 years (Hedge's g 2.75, 95% CI 1.89-3.61, P < 0.001), AHAbd test (WMD 0.7, 95% CI 0.36-1.05, P < 0.001), GMed co-activation (Hedge's g 4.24, 95% CI 3.18-5.3, P < 0.001), and Pain Catastrophizing Scale (WMD 2.85, 95% CI 0.51-5.19, P = 0.02). Altered motor control displayed in AHAbd test and higher lumbar lordosis in individuals over 25 years seem to be probable risk factors for standing-induced LBP. In order to detect standing-induced LBP risk factors, future researchers should investigate the association of the reported distinctive characteristics to the standing-induced LBP and that whether they are manipulable through various interventions.

The effectiveness of the comprehensive corrective exercise program on kinematics and strength of lower extremities in males with dynamic knee valgus: a parallel-group randomized wait-list controlled trial.

BACKGROUND: Dynamic knee valgus (DKV) is a prevalent movement impairment widely regarded as a risk factor for lower extremity disorders such as patellofemoral pain syndrome. The present study aimed to investigate the effectiveness of the comprehensive corrective exercise program (CCEP) on kinematics and strength of lower extremities in males with DKV. METHODS: Thirty asymptomatic young men with DKV between the ages of 18 and 28 years participated in this study. They were randomly assigned to the intervention (n = 15) and control groups (n = 15). The intervention group performed the CCEP for three sessions per week for eight weeks, while the control group only did activities of daily living. Hip external rotator and abductor muscle strength and three-dimensional lower extremity kinematics consisting of knee varus/valgus, femur adduction/abduction, femur medial/lateral rotation, and tibial medial/lateral rotation were measured at the baseline and post-test. The data were analyzed using the analysis of covariance (ANCOVA). RESULTS: There were significant improvements in all kinematics variables in the intervention group after the 8-week CCEP. Moreover, the strength of abductor and external rotator muscle improved in the intervention group (P < 0.05). CONCLUSIONS: The CCEP led to substantial improvements in the selected variables of lower extremity kinematics and muscle strength in participants with DKV during a single-leg squat. These results imply that practitioners should adopt a comprehensive approach to pay simultaneous attention to both proximal and distal segments for improving DKV. TRIAL REGISTRATION: The protocol has been approved in the Registry of Clinical Trials (Registration N: IRCT20180821040843N1 ) on 2018-12-30.

A comparison of functional movement patterns between female low back pain developers and non-pain developers.

BACKGROUND: Distinctive features of low back pain-developers (LBPDs) as pre-clinical low back pain (LBP) population have been evidenced in three areas of alignment, muscle activation, and movement patterns. To clarify whether the reported altered functional movement patterns in chronic LBP patients result from or result in LBP disorders, LBPDs' functional movement patterns should be investigated. OBJECTIVES: This study aimed to compare female LBPDs' functional movement patterns with non-pain developers' (NPDs). METHODS: Sixty female LBPDs and NPDs were recruited based on the research requirements. The Functional Movement Screen (FMS) was used to investigate movement quality. Data were compared between groups via Mann-Whitney U tests and correlation analyses examined association between pain intensity and onset during prolonged standing and the FMS score. Receiver Operating Characteristic Curves and Chi Squares were conducted to find the best cutoff points. An alpha level of p≤0.05 was used to establish statistical significance. RESULTS: LBPDs scored significantly lower, or rather worse than NPDs in the FMS composite score (12.06±1.33 vs. 16.43±1.59, U = 3, P < 0.001). Moreover, the optimal cutoff scores of≤14 on the FMS, 2 on the push-up, and 1 on the deep squat discriminated between female LBPDs and NPDs. The FMS composite score was correlated negatively with LBP intensity (r (60) = -0.724, p < 0.001) and positively with LBP onset (r (60) = 0.277, p = 0.032) during prolonged standing. Finally, the results indicated that female LBPDs presented with at least one bilateral asymmetry on the FMS had 10 times (95% CI, 2.941-34.008) and with at least two bilateral asymmetries on the FMS had 15.5 times (95% CI, 3.814-63.359) higher odds of developing LBP during prolonged standing than NPDs. CONCLUSIONS: Female LBPDs, who are at higher risk for developing LBP in the future, have significantly lower quality of functional movement patterns compared to NPDs. Moreover, the FMS appears to show promise for predicting individuals who are at risk for LBP development during prolonged standing.

Epidemiology and history of knee injury and its impact on activity limitation among football premier league professional referees.

BACKGROUND: The purpose of this study was to determine the epidemiology and history of knee injury and its impact on activity limitation among football premier league professional referees in Iran. METHODS: This was a descriptive study. 59 Football Premier League professional referees participated in the study. The knee injury related information such as injury history and mechanism was recorded. Injury related symptoms and their impacts on the activity limitation, ability to perform activities of daily living as well participation in sports and recreational activities was obtained through the Knee Outcome Survey (KOS). RESULTS: The results indicated that 31 out of 59 participants reported the history of knee injury. In addition, 18.6%, 22.4% and 81% of the referees reported that they had been injured during the last 6 months of the last year, and at some point in their refereeing careers, respectively. Results further indicated that 48.8% of the injuries occurred in the non-dominant leg and they occurred more frequently during training sessions (52%). Furthermore, the value of KOS was 85 ± 13 for Activities of Daily Living subscale and 90 ± 9 for Sports and Recreational Activities subscale of the KOS. CONCLUSIONS: Knee injury was quite common among the Football Premier League professional referees. It was also indicated that the injuries occurred mainly due to insufficient physical fitness. Therefore, it is suggested that football referees undergo the proper warm-up program to avoid knee injury.