Q-angle represents the resultant force vector of the quadriceps and patellar tendons acting on the patella. An increased Q-angle has been considered a risk factor for many disorders and injuries. This literature review challenges the clinical value of static Q-angle and recommends a more dynamic movement evaluation for making clinical decisions. Although there are many articles about static Q-angle, few have assessed the value of dynamic Q-angle. We searched Scopus and PubMed (until September 2021) to identify and summarize English-language articles evaluating static and dynamic Q-angle, including articles for dynamic knee valgus (DKV) and frontal plane projection angle. We also used textbooks and articles from references to related articles. Although static Q-angle measurement is used systematically in clinical practice for critical clinical decisions, its interpretation and clinical translation present fundamental and intractable limitations. To date, it is acceptable that mechanisms that cause patellofemoral pain and athletic injuries have a stronger correlation with dynamic loading conditions. Dynamic Q-angle has the following three dynamic elements: frontal plane (hip adduction, knee abduction), transverse plane (hip internal rotation and tibia external rotation), and patella behavior. Measuring one out of three elements (frontal plane) illustrates only one-third of this concept. Static Q-angle lacks biomechanical meaning and utility for dynamic activities. Although DKV is accompanied by hip and tibia rotation, it remains a frontal plane measurement, which provides no information about the transverse plane and patella movement. However, given the acceptable reliability and the better differentiation capability, DKV assessment is recommended in clinical practice.

Background: While obesity has been shown to elevate the risk of developing multiple sclerosis (MS), there is a lack of strong evidence regarding its role in the disability progression and status of MS patients. Methods: This systematic review and meta-analysis aimed to provide comparative estimates of WC and BMI in patients with MS (PwMS) and to investigate potential associations between the waist circumference (WC) and body mass index (BMI) and demographic and specific MS characteristics. Adhering to PRISMA guidelines, a detailed search of the MEDLINE PubMed, Cochrane Library, and Scopus databases was conducted. Results: A total of 16 studies were included. The pooled mean WC and BMI among PwMS was estimated to be 87.27 cm (95%CI [84.07; 90.47]) and 25.73 (95%CI [25.15; 26.31]), respectively. Meta-regression models established a significant bidirectional relationship between WC and the Expanded Disability Scale (EDSS) (p < 0.001) but not between BMI and EDSS (p = 0.45). Sensitivity analyses showed no association between WC and age (p = 0.48) and a tendency between WC and disease duration (p = 0.08). Conclusions: Although WC measurements classify PwMS as normal weight, BMI measurements classify them as overweight. Therefore, WC should complement BMI evaluations in clinical practice. Additionally, our findings highlight the significant association between abdominal fat, as indicated by WC, and disease progression. Considering the heightened risk of cardiovascular comorbidity and mortality among PwMS, we recommend integrating both WC and BMI as standard anthropometric measurements in routine clinical examinations and targeted prevention strategies for PwMS.

Background: The 12-item International Hip Outcome Tool (iHOT12) is a patient-reported outcome (PRO) designed to evaluate quality of life. We assessed the psychometric properties of the Greek version (iHOT12-Gr) in hip osteoarthritic patients. Methods: Data from 124 patients aged > 50 years were used for factor analysis. Reliability evaluation included internal consistency, test-retest reliability, and interpretability. Content validity was examined by calculating the item-level content validity indices (I-CVI) and the scale-level content validity indices (S-CVI), using two methods: S-CVI Average (S-CVI/Ave), and the S-CVI Universal Agreement among experts (S-CVI/UA). Construct validity was tested against Greek versions of the Lower Extremity Functional Scale (LEFS-Greek), Modified Harris Hip Score (MHHS-Gr), and the 30 s chair-to-stand, Timed Up & Go (TUG), and 9-stairs-ascend/descend (9S-A/D) tests. Known-groups validity was examined using LEFS-Greek (cut-off = 53 points) as estimate variable. Responsiveness was examined pre and post total hip arthroplasty (4 and 8 weeks). Results: Factor analysis revealed a two-factor model. Factor-1 (items 1–9) reflects “Symptoms and functionality”, while Factor-2 (items 10–12) reflects “Hip disorder-related concerns”. Reliability: Internal consistency and test-retest reliability of iHOT12-Gr-total were excellent: Cronbach’s alpha > 0.92 and ICC(95% CI) > 0.976(0.96–0.99)(p < 0.001). Interpretability: There was no floor or ceiling effect; measurement error: 3.72 (Factor-1), 3.64 (Factor-2), and 3.22 (iHOT12-Gr-total); minimal detectable change: 10.3 (Factor-1), 10.1 (Factor-2), and 8.92 (iHOT12-Gr-total). Validity: Content validity: The I-CVI value of the 12 items ranged from 1.00 to 0.83, the S-CVI/Ave was 0.97 and the S-CVI/UA was 0.83. Construct validity: iHOT12-Gr correlated strongly with both LEFS-Greek and MHHS-Gr, and weakly but significantly with 30s chair-to-stand, TUG and 9S-A/D (p < 0.001). Known-groups validity showed that iHOT12-Gr well discriminated subgroups of patients (p < 0.001). ROC analysis cut-off points were 51.9 (Factor-1), 25 (Factor-2) and 45.2 (iHOT12-Gr-total) (p < 0.001). Responsiveness: Four and 8 weeks postoperatively, standardized response means of Factor-1, Factor-2, and iHOT12-Gr-total were > 0.8. Conclusion: iHOT12-Gr showed excellent reliability properties. The content validity was excellent and significant weak-to-strong correlations were found regarding construct validity. The known-group validity was also significant, while the responsiveness was excellent. iHOT12-Gr could be a reliable and valid PRO for assessing quality of life in patients with hip osteoarthritis.

Background: The recurrence rate of lumbar spine microdiscectomies (rLSMs) is estimated to be 5–15%. Lumbar spine flexion (LSF) of more than 10° is mentioned as the most harmful load to the intervertebral disc that could lead to recurrence during the first six postoperative weeks. The purpose of this study is to quantify LSFs, following LSM, at the period of six weeks postoperatively. Methods: LSFs were recorded during the daily activities of 69 subjects for 24 h twice per week, using Inertial Measurement Units (IMU). Results: The mean number of more than 10 degrees of LSFs per hour were: 41.3/h during the 1st postoperative week (P.W.) (29.9% healthy subjects-H.S.), 2nd P.W. 60.1/h (43.5% H.S.), 3rd P.W. 74.2/h (53.7% H.S.), 4th P.W. 82.9/h (60% H.S.), 5th P.W. 97.3/h (70.4% H.S.) and 6th P.W. 105.5/h (76.4% H.S.). Conclusions: LSFs constitute important risk factors for rLDH. Our study records the lumbar spine kinematic pattern of such patients for the first time during their daily activities. Patients’ data report less sagittal plane movements than healthy subjects. In vitro studies should be carried out, replicating our results to identify if such a kinematic pattern could cause rLDH. Furthermore, IMU biofeedback capabilities could protect patients from such harmful movements.