Background: Transcranial direct current stimulation (tDCS) of the motor cortex (M1) produces short-term inhibition of pain. Unihemispheric concurrent dual-site tDCS (UHCDS-tDCS) over the M1 and dorsolateral prefrontal cortex (DLPFC) has greater effects on cortical excitability than when applied alone, although its effect on pain is unknown. The aim of this study was to test if anodal UHCDS-tDCS over the M1 and DLPFC in healthy participants could potentiate conditioned pain modulation (CPM) and diminish pain temporal summation (TS). Methods: Thirty participants were randomized to receive a sequence of UHCDS-tDCS, M1-tDCS and sham-tDCS. A 20 min 0.1 mA/cm² anodal or sham-tDCS intervention was applied to each participant during three test sessions, according to a triple-blind cross-over trial design. For the assessment of pain processing before and after tDCS intervention, the following tests were performed: tourniquet conditioned pain modulation (CPM), pressure pain temporal summation (TS), pressure pain thresholds (PPTs), pressure pain tolerance, mechanosensitivity and cold hyperalgesia. Motor function before and after tDCS intervention was assessed with a dynamometer to measure maximal isometric grip strength. Results: No statistically significant differences were found between groups for CPM, pressure pain TS, PPT, pressure pain tolerance, neural mechanosensitivity, cold hyperalgesia or grip strength (p > 0.05). Conclusions: Neither UHCDS-tDCS nor M1-tDCS facilitated CPM or inhibited TS in healthy subjects following one intervention session.

Background/Objectives: The validity of shoulder orthopaedic test to establish a diagnosis has been recently challenged. For this reason, functional tests, such as the Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) have commenced to be used in clinical settings. The aim of this study is to compare the electromyography (EMG) activity during the CKCUEST and the modified CKCUEST in healthy adult population. Methods: Ten male and 10 female participants were recruited from a University setting. Edinburgh Handedness Inventory, the International Physical Activity Questionnaire and the percentage of activation of the maximum voluntary contraction of the infraspinatus, anterior deltoid and upper trapezius, of both upper limbs, throughout the CKCUEST and modified CKCUEST were analysed. Results: The percentage of activation of infraspinatus (p<0.01), anterior deltoid (p<0.01) and upper trapezius (p0,05), anterior deltoid (p>0,05) and upper trapezius (p>0,05) in both sides during the CKCUEST. Conclusions: The results of this research showed a higher percentage of EMG activation during the CKCUEST compared to the modified CKCUEST in all the muscular structures analysed, regardless of the participants' hemibody.

Background/Objectives: The validity of shoulder orthopaedic tests to establish a diagnosis has recently been challenged. For this reason, functional tests, such as the Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), have started to be used in clinical settings. The aim of this study is to compare the electromyography (EMG) activity during the CKCUEST and the modified CKCUEST in a healthy adult population. Methods: Ten male (age: 26.6 ± 4.8) and ten female participants (age: 24.2 ± 6.0) were recruited from a university setting. The Edinburgh Handedness Inventory, the International Physical Activity Questionnaire and the percentage of activation of the maximum voluntary contraction of the infraspinatus, anterior deltoid and upper trapezius, of both upper limbs, throughout the CKCUEST and modified CKCUEST were analysed. Results: The percentage of activation of the infraspinatus (p < 0.01), anterior deltoid (p < 0.01) and upper trapezius (p < 0.01) in both sides was significantly higher in the CKCUEST compared to the modified CKCUEST. No differences were observed between laterality and the activation percentage of the infraspinatus (p > 0.05), anterior deltoid (p > 0.05) and upper trapezius (p > 0.05) in both sides during the CKCUEST. Conclusions: The results of this research showed a higher percentage of EMG activation during the CKCUEST compared to the modified CKCUEST in all the muscular structures analysed, regardless of the participants’ hemibody.