Journal of Functional Morphology and Kinesiology

Objectives: The acromiohumeral distance (AHD) is widely used to evaluate subacromial pathology, particularly rotator cuff–related disorders. However, substantial heterogeneity exists across studies in imaging protocols, measurement definitions, and diagnostic thresholds. This systematic review aimed to synthesize current evidence on AHD measurement methods, assess reliability and diagnostic performance across imaging modalities, and examine the clinical relevance of AHD as both a structural and functional biomarker. Methods: A systematic search of PubMed, Web of Science, and SciELO (January 2006–May 2025) was conducted following PRISMA 2020. Eligible studies reported quantitative AHD measurements using ultrasound, MRI, or radiography in adults. Two reviewers independently conducted screening, extraction, and QUADAS-2 assessments. Due to heterogeneity, results were narratively synthesized. Results: Twenty-nine studies met the inclusion criteria. Definitions of AHD and imaging procedures varied substantially. Ultrasound showed the most consistent intra- and inter-observer reliability, whereas MRI and radiography demonstrated greater protocol-dependent variability. Reduced AHD values were frequently associated with full-thickness rotator cuff tears, while larger values typically characterized asymptomatic individuals. Several studies also reported reductions in AHD during arm elevation, supporting its interpretation as a functional parameter influenced by scapular motion and neuromuscular control. Conclusions: AHD is a reliable and clinically informative measure when acquired using standardized protocols, with Ultrasound demonstrating the highest reproducibility. Its sensitivity to positional and dynamic factors supports its role as both a structural and functional biomarker. Further research should prioritize standardized imaging procedures, dynamic assessment methods, and evaluation of emerging technologies to improve the diagnostic and prognostic value of AHD.

Background: Motor competence (MC) is defined as the ability to perform a wide range of motor skills with proficiency and control. The present quasi-experimental study design examines the impact of two structured intervention programs on MC in children who practiced athletics at the same club, aged 6 to 10 years, implemented over 12 weeks. Methods: The sample consisted of 64 children, assigned to two intervention groups: Intervention Group A (IG_A) composed of 15 male and 17 female children (9.57 ± 0.86 years) and Intervention Group B (IG_B), of 14 male and 18 female children (9.08 ± 1.33 years). IG_A received athletics-based training exclusively, three times per week, while IG_B undertook two weekly athletics sessions and one complementary activity session, such as handball, gymnastics, swimming, and motor games. MC was assessed using the modified Körperkoordinationstest für Kinder (KTK3+). The KTK3+ consists of three original KTK tasks, [Backward Balance (BB), Sideways Moving (MS), and Jumping Sideways (JS)] and an additional Eye–Hand Coordination (EHC) task. For statistical analysis, ANOVA repeated measures 2 × 2 was used. Results: In relation to JS, the performance on this test did not change with the intervention programs in either of the two groups. For BB and MS, both groups improved their performances in a similar way through the program implementation. Differently, for EHC, results showed that only IG_B improved its performance significantly (p < 0.001) with the program’s intervention, with a large Cohen’s d effect size (0.84). Finally, as a general analysis, the KTK3+ raw results (RS) and results translated to Global Motor Quotient (GQM), revealed significant differences between IG_A and IG_B post-intervention, with p < 0.001 for both variables’ comparison and with large Cohen’s d effect sizes for both (1.581 for RS and 1.595 for GQM), favoring IG_B. Conclusions: Both programs led to improvements in the various KTK3+ battery tasks. However, only the program that combined athletics training with multiactivity training led to significant improvements in the EHC test and in the overall KTK3+ results of the children involved.

Background: Physical function, muscle strength, and fatigue are often impaired in patients with multiple sclerosis (MS). This study aimed to assess these parameters and their associations. Methods: This cross-sectional study included patients with relapsing-remitting MS. Physical function was assessed using the dynamic gait index (DGI), two-minute walk test (2MWT), and Expanded Disability Status Scale (EDSS). Muscle strength and fatigue were assessed using a load cell (measured in kgf). Generalized linear models (GLMs) with log link and gamma distribution examined the associations between MS and physical function, muscle strength, and fatigue. In the MS group, GLMs explored links between fatigue, muscle strength, and physical function. Results: Forty-seven individuals participated (18 MS; 27 controls). Patients with MS showed reduced physical function and muscle strength, and higher fatigue. Knee extension fatigue was associated with DGI (Exp β = 0.23; p = 0.03), 2MWT (Exp β = 0.11; p = 0.02), and EDSS (Exp β = 17.17; p < 0.0001); knee flexion fatigue was associated with EDSS (Exp β = 2.45; p = 0.006). Knee flexion and extension strength were also associated with EDSS. Conclusions: Patients with MS show reduced physical function and strength, increased fatigue, and knee muscle performance. The associations between strength, fatigue, and functional outcomes varied in magnitude, with knee-related measures, especially knee extension fatigue, showing the most consistent relationships.