Omitting TMS component from paired associative stimulation with high-frequency PNS: A case series of tetraplegic patients

Objectives: Earlier studies have shown how chronic spinal cord injury (SCI) patients have benefitted from paired associative stimulation (PAS), consisting of high-frequency peripheral nerve stimulation (PNS) and high-intensity transcranial magnetic stimulation (TMS). Since high-frequency PNS is poorly characterized, its therapeutic effect without TMS should be evaluated. We tested the effect of PNS combined with motor imagery in chronic SCI patients using the same parameters of PNS as in earlier PAS-based studies that also used TMS. Methods: Five patients with chronic incomplete SCI and tetraplegia received a 6-week treatment of PNS combined with motor imagery to the weaker upper limb. Patients were evaluated with Manual Muscle Testing (MMT), hand function tests (Box and block, grip and pinch strength dynamometry), and spasticity. Results: There was no significant change in hand function tests or spasticity. MMT values improved significantly immediately after the PNS period (0.59 +/- 0.17, p = 0.043) and in the 1-month follow-up visit (0.87 +/- 0.18, p = 0.043). However, improvement of MMT values was weaker than in chronic tetraplegic patients in a corresponding PAS study that used identical PNS stimulation but also included the TMS component omitted here (Tolmacheva et al., 2019a, Clin Neurophysiol Pract). Conclusions: The lack of effect on functional hand tests with the protocol presented here suggests that the synergistic effect of PNS and TMS components is essential for the full therapeutic effect previously observed with PAS intervention. The moderate improvement of the MMT score suggests the possible usefulness of PNS and motor imagery for some of those tetraplegic SCI patients who have contraindications to TMS. Significance: These results add to the understanding of the PAS therapeutic mechanism by highlighting the importance of dual stimulation for achieving the full therapeutic effect of long-term PAS with a high-frequency PNS component. (C) 2021 International Federation of Clinical Neurophysiology. Published by Elsevier B.V.Peer reviewe

Occupational differences in disability retirement due to a shoulder lesion : do work-related factors matter?

Objective To identify occupations with a high risk of disability retirement due to a shoulder lesion and to examine the effect of physical and psychosocial work-related factors on occupational differences in disability retirement. Methods We followed Finnish wage earners aged 30-59 years (n = 1,135,654) from 2005 to 2014 for full disability retirement due to a shoulder lesion. The work-related exposures were assessed with job exposure matrices. We calculated age-adjusted incidence rates and hazard ratios to test for the association between occupation and disability retirement due to a shoulder lesion. We also examined the contribution of work-related exposures to the excess risk of disability retirement. Results As compared to professionals, the age-adjusted risk of disability retirement was increased among men in all occupational groups except managers and customer service clerks and among women in several occupational groups. Adjustment for education attenuated the occupational differences considerably, particularly among women. The physical work-related factors fully explained the excess risk of disability retirement due to a shoulder lesion among male finance and sales associate professionals and administrative secretaries as well as among agricultural and fishery workers. In women, the physical work-related factors fully explained the excess risk among construction workers, electricians and plumbers. For both genders, the contribution of psychosocial factors to excess risk of disability retirement was modest and seen for monotonous work only. Conclusions A reduction of the level of physical work load factors as well as monotonousness of work has a potential to prevent work disability due to a shoulder lesion.Peer reviewe

DOES MAGNETIC RESONANCE IMAGING PROVIDE SUPERIOR RELIABILITY FOR ACHILLES AND PATELLAR TENDON CROSS-SECTIONAL AREA MEASUREMENTS COMPARED WITH ULTRASOUND IMAGING?

This study investigated the reliability of Achilles and patellar tendon cross-sectional area (CSA) measurement using ultrasound imaging (USI) and magnetic resonance imaging (MRI). Fifteen healthy adults were imaged twice on two occasions, interrupted by a tendon loading protocol. Tendon CSA segmentations were conducted by an experienced and an inexperienced rater blinded to information regarding subject, session and loading status. USI provided good test-retest reliability (intra-class correlation coefficient [ICC] 2,1 > 0.85, standard error of measurement [SEM] 5%-6%), while with MRI it was excellent (ICC 2,1 > 0.92, SEM 4%) for the experienced rater. This study suggests that MRI provides superior reliability for tendon CSA measurements compared with USI. However, the difference in reliability between the methods was small, and the results were inconclusive regarding objectivity and sensitivity to change when assessed based on the effect of loading. We concluded that both methods can be used for reliable CSA measurements of the Achilles and patellar tendons when using a highly standardized measurement protocol and when conducted by an experienced rater. (C) 2019 World Federation for Ultrasound in Medicine & Biology. All rights reserved.Peer reviewe

Dynamic ticket pricing: How consumer perceptions of fairness affect purchase decisions

Dynamic pricing has existed as a phenomenon already for decades, especially in hotel and airline industries. It is a pricing strategy, which involves maximizing revenue by adjusting the prices based on demand and other factors even on a real-time basis. In the event industry, it is a rather new idea and ticketing companies have mainly utilized it only in sports events. While this pricing strategy can increase revenue and help ticket sellers better manage their product sales, it has also been criticized for potentially being unfair to consumers. Consumers might perceive dynamic ticket pricing unfair if they believe prices are not transparent enough, if they feel that they do not match the perceived value of the event or if they believe other customers are given an advantage. It is important to research this area to understand consumers’ actions and decisions. Previous research in dynamic ticket pricing has focused on sports events, the financial side of them and the consumer’s experience with the events. Research on consumer perceptions is quite extensive, however there seems to be hardly any research focusing generally on the event industry. Through a literature review, this thesis aims to form an understanding of the main theories and frameworks behind the phenomenon and contribute to the academic discussion on consumers’ perception of fairness in dynamic ticket pricing. However, it is not the objective of this thesis to examine through every single factor in fairness perceptions but to examine the most important ones. The results seem to indicate that consumer’s perception of fairness is one of the most important factors in purchase decision with value, quality, and price perceptions. Factors contributing to the fairness perceptions are complex and multi-layered, such as pricing transparency, pricing timing, buyer-seller relationship, reference prices and general knowledge of the prices and market. Compared to fixed pricing, the unclarity of the pricing mechanism might complicate the fairness perception and for instance the trust and history between buyer and seller might be more important. This thesis aims to constitute a solid understanding of the main theories behind fairness perceptions. For future research, the objectives could be to examine other perceptions or different layers of fairness perceptions. For practical implications, this thesis aims additionally to help ticket sellers understand consumer fairness perceptions and their increasing importance in the era of personalized pricing

Work participation and working life expectancy after a disabling shoulder lesion

Objective T o examine the impact of a disabling nontraumatic shoulder lesion on work participation and working life expectancy. Methods From a 70% random sample of the Finnish population, we selected 30-59-year-old wage earners with prolonged sickness absence due to a shoulder lesion (n=7644). We followed the persons from 2006 to 2014 and calculated the proportion of time a person spent in different work participation statuses. The associations of potential determinants with a preterm exit from paid employment were tested using Cox regression. Years expected to be spent in different work participation statuses were estimated applying the Sullivan method for healthy life expectancy. Results During 9 years of follow-up time spent at work was reduced from 77.7% to 46.7%, and 15.8% of the persons were granted disability retirement, mostly due to shoulder and other musculoskeletal diseases. Compared with the general population persons with a disabling shoulder disease are expected to lose from 1.8 to 8.1 years of working life, depending on their age. Age, gender, education, duration of initial sickness absence due to the shoulder lesion, not being able to return to work sustainably and participation in vocational rehabilitation predicted preterm exit from work. Heavy lifting increased the risk of preterm exit marginally. Conclusions Working life expectancy is markedly reduced in persons with a disabling shoulder lesion, mainly because of disability retirement due to musculoskeletal problems. Clinicians should consider interventions targeted at improving musculoskeletal functioning and necessary work modifications before shoulder problems become chronic or the persons develop disabling comorbid musculoskeletal conditions.Peer reviewe

Occupational and non-occupational risk factors of sickness absence due to a shoulder lesion

Objectives To determine the associations of lifestyle factors and cumulative physical workload exposures with sickness absence (SA) due to a shoulder lesion and to calculate their population attributable fractions (PAF). Methods Our nationally representative cohort consisted of 4344 individuals aged 30-62 years who participated in the Finnish Health 2000 Survey. Education, smoking, chronic diseases and work exposures were assessed during interviews and leisure time physical activity with a questionnaire. Weight and height were measured. We followed the individuals for 15 years for the first SA due to a shoulder lesion. We used competing risk regression models. We calculated PAFs to assess the proportion of SA that was attributed to modifiable risk factors. Results In the entire study population, risk factors of SA were age, daily smoking, being exposed for more than 10 years to physically heavy work and being exposed for more than 10 years to at least two specific physical workload factors. The overall PAF for the modifiable risk factors was 49%. In men, number of specific cumulative exposures, obesity and daily smoking predicted SA with PAF values of 34%, 30% and 14%, respectively. Among women, being exposed for more than 10 years to physically heavy work, number of specific cumulative exposures and daily smoking accounted for 23%, 22% and 15% of SA, respectively. Conclusions Reducing significantly prolonged exposure to physical workload factors, avoiding regular smoking in both genders and obesity in men has a high potential to prevent SA due to a shoulder lesion.Peer reviewe

Physical performance after pediatric solid organ transplantation

Introduction Low physical activity is a well-recognized problem in pediatric solid organ transplant recipients; however, little is known about the differences between transplant groups. Physical performance testing was performed in a cohort of pediatric kidney, liver, and heart transplant recipients. Methods Fifty-one patients (54.9% boys), including 17 liver, 20 kidney, 2 combined liver-kidney, and 12 heart transplant recipients, were tested at the median age of 11.5 (7.5-14.9) years. The results were compared with a control group, which consisted of 425 healthy schoolchildren. The physical performance test included six different tests of endurance, strength, flexibility, and speed. Results The transplant recipients performed worse on most tests when compared with the control subjects (leg-lift test 42.0 vs. 44.9 repetitions, p = .002; repeated squatting 21.6 vs. 23.9 repetitions, p < .001; sit-up test 9 vs. 17 vs. 9 repetitions, p < .001, back extension 20 vs. 35 repetitions, p < .001; and shuttle run test 26.5 vs. 23.7 seconds, p < .001). None of the test results differed statistically significantly between the transplant groups. Conclusion The physical performance of pediatric solid organ transplant recipients is lower than that of their healthy peers but do not differ between different transplant groups. More systematic rehabilitation programs and follow-up are needed.Peer reviewe

Optimal peripheral nerve stimulation intensity for paired associative stimulation with high-frequency peripheral component in healthy subjects

Publisher Copyright: © 2022, The Author(s).Paired associative stimulation (PAS) with high-frequency peripheral nerve stimulation (PNS), called “high-PAS”, induces motor-evoked potential (MEP) potentiation in healthy subjects and improves muscle activity and independence in incomplete spinal cord injury patients. Data on optimal PNS intensity in PAS are scarce. In a high-PAS protocol, PNS intensity is defined as “minimal intensity required to produce F-responses”. We sought to further refine this definition and to investigate how PNS intensity affects PAS outcome. Two experiments were performed on 10 healthy subjects where MEP amplitude change was measured 0, 30, and 60 min after PAS. In the first experiment, the intensity required to achieve 7/10 persistence of F-responses was used to define PNS intensity level. In the second experiment, we used the intensity required to achieve 1/10 persistence (“baseline”). In addition, we applied this intensity at + 25%, − 25%, and − 50% levels. In the first experiment, PAS did not produce significant MEP potentiation. In the second experiment, PAS produced statistically significant MEP potentiation, with PNS intensity of “baseline” and “baseline − 25%” levels but not at + 25% or − 50% levels. In conclusion, for PAS utilizing high-frequency PNS, the intensity required to achieve 1/10 F-response persistence or the intensity 25% lower produces significant MEP potentiation in healthy subjects.Peer reviewe