Flávia Pessoni Faleiros Macêdo

Background: Handgrip strength (HGS) is a key indicator of upper limb function and overall health. While the Jamar dynamometer is considered the gold standard for HGS assessment, alternatives like the Jamar Plus+ and Biodex have emerged, though their reliability and agreement remain underexplored. Aim: To evaluate the test–retest reliability and agreement of the Jamar, Jamar Plus+, and Biodex dynamometers in healthy young adults. Methods: This exploratory cross-sectional study included 35 participants (22 females, 13 males; mean age 23.4 years). HGS was assessed using the three devices, following standardised protocols, with retest after 7 days. Reliability was analysed using the Intraclass Correlation Coefficient (ICC), Standard Error of Measurement (SEM), and Minimal Detectable Change (MDC). Agreement was examined through Bland–Altman plots and Limits of Agreement (LoA %). Results: Jamar and Jamar Plus+ showed excellent reliability (ICC = 0.96–0.98) and strong agreement, with narrow LoA percentages and low measurement error, especially on the non-dominant hand. In contrast, comparisons involving the Biodex revealed wider LoA (up to ±73%) and higher SEM and MDC values, indicating lower agreement with handheld devices. These discrepancies are likely due to differences in measurement principles, hand positioning, and unit conversion. Male participants showed significantly higher grip strength across all instruments. Conclusion: The Jamar and Jamar Plus+ can be used interchangeably. The Biodex may be considered when appropriate adjustments are made, though its agreement with handheld dynamometers is limited. These findings highlight the need for standardised protocols and further research to ensure consistent and reliable HGS assessment across devices.

Background: Work-related musculoskeletal disorders (WRMD) may be associated with various individual, physical, biomechanical, or psychosocial/organisational risk factors. Self-report questionnaires have increasingly been used to assess patients’ perceptions of injury impact. QuickDASH is a widely used outcome measurement questionnaire but is seldom applied to WRMD. Objective: To evaluate the construct validity of the Brazilian version of the QuickDASH (QD-Br) in patients with WRMD affecting the upper limbs, hypothesising a moderate correlation with fatigue, ergonomic, and functional questionnaires. Methods: Workers of a tertiary hospital, such as healthcare professionals and support staff employees with WRMD in the upper limbs and neck were included. The outcome measures were QD-Br, the Numerical Pain Scale (NPS), Isometric Handgrip Strength (GS), Isokinetic Force of Bilateral Shoulder Elevation in the Scapular Plane (ISOAbd), Functional Impairment Test - Hand and Neck/Shoulder/Arm (FIT-HaNSA), and: Patient-Specific Functional Scale (PSFS-Br), Neck Disability Index (NDI-Br), Work Ability Index (WAI-Br), Need for Recovery Scale (NFR-Br), and Quick Exposure Checklist (QEC-Br). Spearman’s Correlation Coefficient (ρ) was calculated to determine the direction and strength of associations. Results: The sample was 70% female, 63% reporting chronic symptoms. The shoulder was the joint most frequently reported. QD-Br showed moderate positive correlations with NDI-Br and NPS and moderate but negative correlations with WAI-Br and PSFS-Br. It presented weak and positive correlations with NFR-Br, weak and negative correlations with GS, ISOAbd, and FIT-HaNSA, and no correlation with QEC-Br. Conclusion: QD-Br demonstrated evidence of construct validity for assessing workers with upper limb complaints, effectively reflecting their dysfunctions and symptoms.

BACKGROUND: Work-related shoulder disorders adversely affect the quality of life and lead to increased costs related to decreased productivity and injury treatment. Therefore, understanding the relationship between strength, upper extremity function and work ability contributes to the development of interventions aimed to improve the well-being of healthcare workers. OBJECTIVE: Correlate shoulder abduction and handgrip strength with upper extremity function and work ability in healthcare workers with shoulder complaints. METHODS: 67 workers with shoulder pain in the last year were assessed by Disability of Arm, Shoulder and Hand (QuickDASH), Work Ability Index (WAI), isokinetic shoulder strength and isometric handgrip strength dynamometers. Data were analysed with Spearman’s Correlation Coefficient (ρ= 0.05), SPSS 20.0®. RESULTS: 52% males, mean age 48.4 years, 42% physically active, most administrative and general services workers. Low correlation between handgrip strength and QuickDASH (r=-0.359; p = 0.004); low correlation between handgrip strength and WAI (r = 0.359; p = 0.003) and between shoulder abduction strength and the QuickDASH (r = -0.267; p = 0.049); no significant correlation between shoulder abduction strength and WAI (r = 0.001; p = 0.997). CONCLUSIONS: Handgrip and shoulder abduction strength were inversely associated with upper extremity dysfunction. Shoulder abduction strength was associated with work ability. The inclusion of strength assessment in workers is important to guide strategies to prevent musculoskeletal disorders.

In upper extremity peripheral nerve injuries, orthotic intervention has been used as a valuable device to restore function. However, there is lacking evidence to support it. The purpose of this study was to explore the application of body function’s outcome measures for orthotic intervention evaluation in patients with peripheral nerve injury. Two participants sustaining a peripheral nerve injury who underwent orthotic intervention were assessed: subject 1 was a 25-year-old man with ulnar and median nerve injury presenting with a composite claw; subject 2, a 28-year-old man with radial nerve injury presenting with a dropped wrist. Strength, range of motion, and electromyography were measured in 2 conditions: wearing the orthosis and without it. The Jamar, Pinch Gauge, a 3D motion capture system (Optitrack-NaturalPoint), and surface electromyography (Trigno Wireless System, Delsys) were the chosen instruments. Both subjects presented differences in grip and pinch strength. In both tasks, subject 1 reached higher wrist extension while wearing the orthosis. Subject 2 reached higher wrist extension and radial deviation while wearing the orthosis. There were marked differences in both tasks for subject 2, especially the maintenance of wrist extension when wearing the orthosis. Electromyographic assessment showed higher root-mean-square values for all muscles, in both tasks for subject 1. For subject 2, a higher root-mean-square value was found for flexor carpi ulnaris during the execution of task 1 wearing the orthosis. Outcome measures of body function can quantify the impact of orthotic intervention in patients sustaining peripheral nerve injury, and therefore, they are feasible for evaluating it.

Background: Work-related musculoskeletal disorders (WRMDs) are often caused by inadequate use of the musculoskeletal system during work. Evidence suggests that multimodal intervention through exercises, massage, education, and ergonomic guidelines reduces pain and symptoms in the neck and upper extremities and help to prevent musculoskeletal disorders. The purpose of this study will be to assess the additive effectiveness of a specific and individualized workplace strengthening exercise program to an ergonomic guidance in reducing fatigue, pain and discomfort in the upper extremities and neck perceived by workers.Methods: This trial was designed according to the Consolidated Standards of Reporting Trials - CONSORT guidelines. Participants will be employees of a tertiary hospital, with any complaints of pain or discomfort in the upper extremities during the past 12 months, without clinical musculoskeletal diagnosis. 166 participants will be randomized into parallels groups as control and workplace exercises. The primary outcomes will be Numerical Pain Scale, isokinetic muscle strength of abduction and isometric handgrip strength. Secondary outcomes on discomfort, fatigue, work capacity and dysfunction will be assessed by QuickDASH, Patient Specific Functional Scale, Neck Disability Index, Need for recovery, Work Ability Index self-report questionnaires and FIT-HANSA performance test. The Ergonomic Work Analysis will be done by Quick Expose Check, RULA, REBA, RARME, ROSA and HARM risk assessment ergonomic tools. We will analyze the difference between baseline and 12 weeks of intervention by T test of independent samples (95% confidence interval,p < 0.05). Clinical significance will be analyzed by the minimum clinically important difference and effect size by Cohen index. The association between the variables will be analyzed by construct validity with the hypothesis of correlations between pain and muscle strength, strength and functionality and strength and fatigue.Discussion: Although studies have shown promise outcomes for workplace exercises as an available therapeutic resource used to minimize complaints of pain and discomfort related to work, the results of this study aim to bring evidence about the benefit of a specific resistance exercise as an effective modality to facilitate mechanisms of neuromuscular adaptations, with gradual and posterior hypertrophy in the later phases.Trial registration: (NCT04047056,https://clinicaltrials.gov/ct2/show/NCT04047056?term=NCT04047056&draw=2&rank=1) on Dec 03, 2020.

O Functional Impairment Test-Hand and Neck/Shoulder/Arm (FIT-HaNSA) é um instrumento que avalia a resistência à fadiga e o desempenho do membro superior por meio de funções motoras grossas comumente utilizadas no dia a dia. Objetivo: Analisar a validade de construto do FIT-HaNSA em trabalhadores com sintomas no membro superior, por meio da correlação entre a resistência à fadiga do segmento com os escores de força muscular do ombro, cotovelo e mão, com a capacidade para o trabalho (ICT) e com a disfunção do membro superior (QUICK DASH-Br). Métodos: Trinta e nove trabalhadores de um hospital terciário com idade média de 42,9 anos (DP13,29) foram recrutados. Os instrumentos de medida Isocinético Biodex System 4 Pro™, dinamômetro de preensão palmar JAMAR®, QuickDASH-Br e ICT foram aplicados e correlacionados com o FIT-HaNSA. O Coeficiente de Correlação de Pearson (r) foi utilizado para quantificar a associação entre os instrumentos. Resultados: O FIT-HaNSA apresentou de fraca a moderada correlação entre a força muscular do ombro, cotovelo e mão (r= 0,18 – 0,58), porém significativas para ombro e mão. A associação entre o FIT-HaNSA com o QuickDASH-Br e ICT se mostraram fracas (r= -0,38 e 0,21). Conclusão: Nosso estudo forneceu evidências preliminares com relação às relações esperadas e validade do FIT-HaNSA como instrumento de medida para a avaliação da fadiga e desconforto em trabalhadores com queixas no membro superior.