The reliability of side to side measurements of upper extremity activity levels in healthy subjects

<p>Abstract</p> <p>Background</p> <p>In both clinical and occupational settings, ambulatory sensors are becoming common for assessing all day measurements of arm motion. In order for the motion of a healthy, contralateral side to be used as a control for the involved side, the inherent side to side differences in arm usage must be minimal. The goal of the present study was to determine the reliability of side to side measurements of upper extremity activity levels in healthy subjects.</p> <p>Methods</p> <p>Thirty two subjects with no upper extremity pathologies were studied. Each subject wore a triaxial accelerometer on both arms for three and a half hours. Motion was assessed using parameters previously reported in the literature. Side to side differences were compared with the intraclass correlation coefficient, standard error of the mean, minimal detectable change scores and a projected sample size analysis.</p> <p>Results</p> <p>The variables were ranked based on their percentage of minimal detectable change scores and sample sizes needed for paired t-tests. The order of these rankings was found to be identical and the top ranked parameters were activity counts per hour (MDC% = 9.5, n = 5), jerk time (MDC% = 15.8, n = 8) and percent time above 30 degrees (MDC% = 34.7, n = 9).</p> <p>Conclusions</p> <p>In general, the mean activity levels during daily activities were very similar between dominant and non-dominant arms. Specifically, activity counts per hour, jerk time, and percent time above 30 degrees were found to be the variables most likely to reveal significant difference or changes in both individuals and groups of subjects. The use of ambulatory measurements of upper extremity activity has very broad uses for occupational assessments, musculoskeletal injuries of the shoulder, elbow, wrist and hand as well as neurological pathologies.</p

PREDICTING FIREFIGHTERS’ PHYSICAL ABILITY TEST SCORES FROM ANAEROBIC FITNESS PARAMETERS

Peter Beitia1, Zacharias Papadakis1, Andreas Stamatis, FACSM2, Tal Amasay1. 1Barry University, Miami Shores, FL. 2SUNY Plattsburgh, Plattsburgh, NY. BACKGROUND: The physical ability test (PAT) evaluates firefighters’ (FF) fitness to execute occupational tasks. The aerobic system’s contribution to PAT performance is extensive; however, research is inconclusive regarding the involvement of the anaerobic system during PAT. This study aimed to identify relationships between specific anaerobic fitness (AF) tests’ and PAT’s time scores and to create a model to best predict PAT using these AF parameters. METHODS: A preliminary convenience sample of 14 male FFs (Age: 29.0±7.0yrs; Height: 1.7±0.1m; Weight: 79.9±13.0kg; Occupational-Weight: 102.6±13.0kg; BF%: 17.9±5.6%) from two fire departments was used. Data collection took place over two separate days. On day one, FFs completed a PAT composed of occupationally-specific tasks in full gear. On day two, FFs performed a series of anaerobic fitness assessment in full gear: handgrip-dynamometry, maximal vertical-jump, Margaria-Kalamen staircase test, and 300-yard shuttle run (300YD). Pearson-product moment correlation coefficients were used to examine associations between dependent variables and PAT. Multiple backward regression analysis was used to model the PAT using AF parameters (i.e., HG: Handgrip dynamometer absolute strength; VJAPP: Vertical jump absolute peak power; MKAP: Margaria-Kalamen staircase test absolute power; 300YD: 300-yard [274 m] shuttle run test). All statistical analyses were performed with IBM SPSS 27.0, with a significance level of p \u3c 0.05. RESULTS: PAT was significantly correlated with HG (r = -0.71, p \u3c 0.01), VJ (r = -0.73, p \u3c 0.01), MK (r = -0.75, p \u3c 0.01), and non-significantly with 300YD (r = 0.60, p \u3c 0.05). A 78% proportion of variation observed in PAT was explained by the aforementioned AF parameters (F2, 13 = 20.2, p \u3c 0.05). CONCLUSION: The examined anaerobic subsystems significantly contribute to PAT performance. FFs should optimize AF training, which would allow for potentially enhanced occupational performance in PAT. Further investigation into anaerobic physiological determinants of FFs with larger sample size is recommended

The Relation between Scapular Dyskinesis and the Upper Quarter Y-Balance Test

The shoulder is a complex mechanical system. Alterations in the position and/or orientation of its joints may interfere with optimal shoulder coordination. Scapular dyskinesis (SDK) is defined as mal-positioning or mal-movement of the scapula along the thoracic wall. It is not well established the role of scapular dyskinesis as the cause or the effect of shoulder pathologies. The Upper-Quarter Y-Balance test (UQYBT) has been suggested as a return-to-play tool for athletes with upper extremity injuries. The objective of this study was to quantify the relation between the UQYBT and SDK. Six males and five females participated in the study, age 18-30 years old. All participants’ shoulders were evaluated by a certified athletic trainer using Kibler Scapular Dyskinesis Test (SDT) as having dyskinesis or not. Each participant performed three of the SDT and three of the UQYBT. The outcomes of the UQYBT were the highest score for each direction SuperiorLateral Reach (SLR), Inferior-Lateral Reach (ILR), and Medial Reach (MR) and the Composite score. An independent t-test with unequal variances was performed to determine statistical differences between normal and SDK shoulders during the UQYBT. Results indicate significant differences between the normal and SDK shoulders in the Composite score (p=.048). No significance was found during the ILR, SLR, and MR. In conclusions, when the SDK shoulder was stabilizing during the UQYBT higher scores were seen in every direction compared to the normal shoulder. These suggest that SDK may affect the scores of UQYBT