Cross-cultural adaptation and validation of the Dutch version of the High Activity Arthroplasty Score

Introduction: The high Activity Arthroplasty Score ( hAAS) has been designed to differentiate in the functional ability between normal and more active patients after total knee arthroplasty (TKA) and total hip arthroplasty (T hA). no such questionnaire is currently available in the Dutch language. The objective of this study was to evaluate the Dutch version of the hAAS in ThA and TKA patients. Patients & Methods: The forward and backward translated Dutch version of the hAAS combined with the national Dutch patient reported outcome measures (PR oMS) were sent to two hundred patients of all ages who underwent TKA or T hA. The internal consistency, construct validity and ceiling/floor effects of the hAAS were evaluated. Results: 108 patients (51 ThA and 57 TKA) participated in this study. A good internal consistency with a Cronbach’s alpha of 0.78, 0.81 and 0.84 was found in all patients, the Th A and the TKA group respectively. Significant positive correla- tions were observed between the hAAS and VAS Qo l, EQ-5D, all K oo S sub-scores except the symptoms score, and all hoo S sub-scores except the Qo l score. A negative correlation was found with the VAS pain. no ceiling or floor effect was seen in the hAAS. Discussion: The Dutch version of the hAAS can be used to evaluate the functional ability in more active patients of all ages who underwent ThA or TKA with an acceptable internal consistency and construct validity, with no ceiling or floor effects

To Improve Your Surgical Drilling Skills, Make Use of Your Index Fingers

BACKGROUND: Surgery has greatly benefited from various technologic advancements over the past decades. Surgery remains, however, mostly manual labor performed by well-trained surgeons. Little research has focused on improving osseous drilling techniques. The objective of this study was to compare the accuracy and precision of different orthopaedic drilling techniques involving the use of both index fingers. QUESTIONS/PURPOSES: (1) Does the shooting grip technique and aiming at the contralateral index finger improve accuracy and precision in drilling? (2) Is the effect of drilling technique on accuracy and precision affected by the experience level of the performer? METHODS: This study included 36 participants from two Dutch training hospitals who were subdivided into three groups (N = 12 per group) based on their surgical experience (that is, no experience, residents, and surgeons). The participants had no further experience with drilling outside the hospital nor were there other potential confounding variables that could influence the test outcomes. Participants were instructed to drill toward a target exit point on a synthetic bone model. There were four conditions: (1) clenched grip without aiming; (2) shooting grip without aiming; (3) clenched grip with aiming at the contralateral index finger; and (4) shooting grip aiming at the contralateral index finger. Participants were only used to a clenched grip without aiming in clinical practice. Each participant had to drill five times per technique per test, and the test was repeated after 4 weeks. Accuracy was defined as the systematic error of all measurements and was calculated as the mean of the five distances between the five exit points and the target exit point, whereas precision was defined as the random error of all measurements and calculated as the SD of those five distances. Accuracy and precision were analyzed using mixed-design analyses of variance. RESULTS: Accuracy was highest when using a clenched grip with aiming at the index finger (mean 4.0 mm, SD 1.1) compared with a clenched grip without aiming (mean 5.0 mm, SD 1.2, p = 0.004) and a shooting grip without aiming (mean 4.9 mm, SD 1.4, p = 0.015). The shooting grip with aiming at the index finger (mean 4.1 mm, SD 1.2) was also more accurate than a clenched grip without aiming (p = 0.006) and a shooting grip without aiming (p = 0.014). Shooting grip with aiming at the opposite index finger (median 2.0 mm, interquartile range [IQR] 1.2) showed the best precision and outperformed a clenched grip without aiming (median 2.9 mm, IQR 1.1, p = 0.016), but was not different than the shooting grip without aiming (median 2.2 mm, IQR 1.4) or the clenched grip with aiming (median 2.4 mm, IQR 1.3). The accuracy of surgeons (mean 4.1 mm, SD 1.1) was higher than the inexperienced group (mean 5.0 mm, SD 1.1, p = 0.012). The same applied for precision (median 2.2 mm, IQR 1.0 versus median 2.8 mm, IQR 1.4, p = 0.008). CONCLUSIONS: A shooting grip combined with aiming toward the index finger of the opposite hand had better accuracy and precision compared with a clenched grip alone. Based on this study, experience does matter, because the orthopaedic surgeons outperformed the less experienced participants. Based on our study, we advise surgeons to aim at the index finger of the opposite hand when possible and to align the ipsilateral index finger to the drill bit. LEVEL OF EVIDENCE: Level II, therapeutic study

Marker location and knee joint model constraint affect the reporting of overhead squat kinematics in elite youth football players

Motion capture systems are used in the analysis and interpretation of athlete movement patterns for a variety of reasons, but data integrity remains critical regardless of the purpose of measurement. The extent to which marker location or constraining degrees of freedom in the biomechanical model impacts on this integrity lacks consensus. Elite youth academy footballers (n=10) performed repeated bilateral overhead squats using a marker-based motion capture system. Kinematic data were calculated using four different marker sets with three degrees of freedom (3DOF) and six degrees of freedom (6DOF) configurations for the three joint rotations of the right knee. Root mean squared error (RMSE) differences between marker sets ranged in the sagittal plane between 1.02 and 4.19 degrees to larger values in the frontal (1.30- 6.39 degrees) and transverse planes (1.33 and 7.97 degrees). The cross-correlation function (CCF) of the knee kinematic time series for all eight marker-sets ranged from excellent for sagittal plane motion (>0.99) but reduced for both coronal and transverse planes (< 0.9). Two-way ANOVA repeated measures for marker sets calculated for all directions at peak squat knee flexion revealed significant differences between marker sets for frontal and transverse planes ( < 0.9). Two-way ANOVA repeated measures for marker sets calculated for all directions at peak squat knee flexion revealed significant differences between marker sets for frontal and transverse planes (p < 0.05). Pairwise transverse plane 6DOF marker set comparisons showed significant differences except between the anterior partial cluster and cluster marker sets. The paired 3DOF comparison revealed a significant difference between two of the four marker sets. The 3DOF and 6DOF model comparisons demonstrated significant differences except for the anterior partial cluster. Marker location and constraining DOF while measuring relatively large ranges of motion in this population are important considerations for data integrity. This was particularly evident in the measurement of frontal and transverse kinematics with implications for future studies using motion capture with athletic populations

A different approach for the ergonomic evaluation of pushing and pulling in practice

Abstract Recent epidemiological studies show that pushing and pulling increase the risks of shoulder complaints and not necessarily of low back complaints. Moreover, the magnitude of the exerted hand forces during pushing and pulling is poorly related to the magnitude of the mechanical loading of the low back and the shoulder. In light of that, this paper combines results of several studies to present an approach for evaluating not only the exerted hand forces, but also the low back and shoulder load during pushing and pulling in practice. The approach specifies, based on scientific evidence, that (1) in order to validly obtain exposure (frequency and duration) to pushing and pulling, 10 workers should be observed during eight periods of 30 min; (2) how the exerted hand forces and the load of the low back and shoulder can be estimated in practice based solemnly on the weight of the object, one-handed or two-handed pushing or pulling, and the height of the handle; and finally, (3) how these outcomes can be evaluated in combination with existing guidelines regarding exerted hand forces, compression forces on the low back and the moments at the shoulder. Two cases will be presented here to illustrate the application of the approach. Relevance to industry The presented approach is the first to offer practitioners a fairly simple method for the ergonomic evaluation of pushing and pulling carts and four-wheeled containers in practice, especially as regarding the shoulder load.

Sub-movement organisation, pen pressure and muscle activity are modulated to precision demands in 2D tracking

The authors investigated how tracking performance, submovement organization, pen pressure and muscle activity in forearm and shoulder muscles were affected by target size in a 2D tracking task performed with a pen on a digitizer tablet. Twenty-six subjects took part in an experiment, in which either a small dot or a large dot was tracked, while it moved quasirandomly across a computer screen at a constant velocity of 2cm/s. The manipulation of precision level was successful, because mean distance to target and the standard deviation of this distance were significantly smaller with the small target than with the large target. With a small target, subjects trailed more behind the center of target and used submovements with larger amplitudes and of shorter duration, resulting in higher tracking accuracy. This change in submovement organization was accompanied by higher pen pressure, while at the same time muscle activity in the forearm extensors and flexors was increased, indicating higher endpoint stability. In conclusion, increased precision demands were accommodated by both a different organization of submovements and higher endpoint stability in a 2D tracking task performed with a pen on a digitizer tablet. © 2012 Copyright Taylor and Francis Group, LLC

Where to Step? Contributions of Stance Leg Muscle Spindle Afference to Planning of Mediolateral Foot Placement for Balance Control in Young and Old Adults

Stable gait requires active control of the mediolateral (ML) kinematics of the body center of mass (CoM) and the base of support (BoS) in relation to each other. Stance leg hip abductor (HA) muscle spindle afference may be used to guide contralateral swing foot placement and adequately position the BoS in relation to the CoM. We studied the role of HA spindle afference in control of ML gait stability in young and older adults by means of muscle vibration. Healthy young (n = 12) and older (age &gt; 65 years, n = 18) adults walked on a treadmill at their preferred speed. In unperturbed trials, individual linear models using each subject’s body CoM position and velocity at mid-swing as inputs accurately predicted foot placement at the end of the swing phase in the young [mean R2 = 0.73 (SD 0.11)], but less so in the older adults [mean R2 = 0.60 (SD 0.14)]. In vibration trials, HA afference was perturbed either left or right by vibration (90 Hz) in a random selection of 40% of the stance phases. After vibrated stance phases, but not after unvibrated stance phases in the same trials, the foot was placed significantly more inward than predicted by individual models for unperturbed gait. The effect of vibration was stronger in young adults, suggesting that older adults rely less on HA spindle afference. These results show that HA spindle afference in the stance phase of gait contributes to the control of subsequent ML foot placement in relation to the kinematics of the CoM, to stabilize gait in the ML direction and that this pocess is impaired in older adults

Effectiveness of a questionnaire based intervention programme on the prevalence of arm, shoulder and neck symptoms, risk factors and sick leave in computer workers: A cluster randomised controlled trial in an occupational setting

<p>Abstract</p> <p>Background</p> <p>Arm, shoulder and neck symptoms are very prevalent among computer workers. In an attempt to reduce these symptoms, a large occupational health service in the Netherlands developed a preventive programme on exposure to risk factors, prevalence of arm, shoulder and neck symptoms, and sick leave in computer workers. The purpose of this study was to assess the effectiveness of this intervention programme.</p> <p>Methods</p> <p>The study was a randomised controlled trial. The participants were assigned to either the intervention group or the usual care group by means of cluster randomisation. At baseline and after 12 months of follow-up, the participants completed the RSI QuickScan questionnaire on exposure to the risk factors and on the prevalence of arm, shoulder and neck symptoms. A tailor-made intervention programme was proposed to participants with a high risk profile at baseline. Examples of implemented interventions are an individual workstation check, a visit to the occupational health physician and an education programme on the prevention of arm, shoulder and neck symptoms. The primary outcome measure was the prevalence of arm, shoulder and neck symptoms. Secondary outcome measures were the scores on risk factors for arm, shoulder and neck symptoms and the number of days of sick leave. Sick leave data was obtained from the companies. Multilevel analyses were used to test the effectiveness.</p> <p>Results</p> <p>Of the 1,673 persons invited to participate in the study, 1,183 persons (71%) completed the baseline questionnaire and 741 persons participated at baseline as well as at 12-month follow-up. At 12-month follow-up, the intervention group showed a significant positive change (OR = 0.48) in receiving information on healthy computer use, as well as a significant positive change regarding risk indicators for work posture and movement, compared to the usual care group. There were no significant differences in changes in the prevalence of arm, shoulder and neck symptoms or sick leave between the intervention and usual care group.</p> <p>Conclusions</p> <p>The effects of the RSI QuickScan intervention programme were small, possibly as a result of difficulties with the implementation process of the proposed interventions. However, some significant positive effects were found as to an increase in receiving education and a decrease in exposure to adverse postures and movements. With regard to symptoms and sick leave, only small and non-significant effects were found.</p> <p>Trial registration</p> <p>Netherlands National Trial Register NTR1117</p

The cost-effectiveness of the RSI QuickScan intervention programme for computer workers: Results of an economic evaluation alongside a randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>The costs of arm, shoulder and neck symptoms are high. In order to decrease these costs employers implement interventions aimed at reducing these symptoms. One frequently used intervention is the RSI QuickScan intervention programme. It establishes a risk profile of the target population and subsequently advises interventions following a decision tree based on that risk profile. The purpose of this study was to perform an economic evaluation, from both the societal and companies' perspective, of the RSI QuickScan intervention programme for computer workers. In this study, effectiveness was defined at three levels: exposure to risk factors, prevalence of arm, shoulder and neck symptoms, and days of sick leave.</p> <p>Methods</p> <p>The economic evaluation was conducted alongside a randomised controlled trial (RCT). Participating computer workers from 7 companies (N = 638) were assigned to either the intervention group (N = 320) or the usual care group (N = 318) by means of cluster randomisation (N = 50). The intervention consisted of a tailor-made programme, based on a previously established risk profile. At baseline, 6 and 12 month follow-up, the participants completed the RSI QuickScan questionnaire. Analyses to estimate the effect of the intervention were done according to the intention-to-treat principle. To compare costs between groups, confidence intervals for cost differences were computed by bias-corrected and accelerated bootstrapping.</p> <p>Results</p> <p>The mean intervention costs, paid by the employer, were 59 euro per participant in the intervention and 28 euro in the usual care group. Mean total health care and non-health care costs per participant were 108 euro in both groups. As to the cost-effectiveness, improvement in received information on healthy computer use as well as in their work posture and movement was observed at higher costs. With regard to the other risk factors, symptoms and sick leave, only small and non-significant effects were found.</p> <p>Conclusions</p> <p>In this study, the RSI QuickScan intervention programme did not prove to be cost-effective from the both the societal and companies' perspective and, therefore, this study does not provide a financial reason for implementing this intervention. However, with a relatively small investment, the programme did increase the number of workers who received information on healthy computer use and improved their work posture and movement.</p> <p>Trial registration</p> <p>Trial registration number: NTR1117</p

Effectiveness of a Multidisciplinary Occupational Training Program for Chronic Low Back Pain

Objective: To evaluate the effectiveness of a 12-wk multidisciplinary occupational training program for patients with chronic low back pain and to identify prognostic factors for treatment success. Design: A total of 51 participants were evaluated at baseline, at discharge, and at 1 yr after conclusion of the program. The evaluation included a physical examination and assessment of functional disability, psychological factors, and coping styles. The main target of the program is full work resumption. The central outcome measures therefore are three variables on return to work. Results: Analysis of variance for repeated measures revealed significant beneficial changes during the program for all measures except for several coping-style variables. The acquired level of maximum oxygen uptake, trunk flexibility, functional disability, and catastrophizing were maintained at 1-yr follow-up. At 1-yr follow-up, >60% of the participants had fully returned to work, which is an increase of >40% compared with baseline. Regression analyses showed that sex, age, the baseline values of reinterpretation of pain sensations, and functional disability and changes in trunk flexibility scores during the program are important prognostic factors for complete return to work. Conclusions: Based on the current findings, the program seems to be efficacious in the short term. Future attention must be directed toward maintaining these results, although work resumption rates improved considerably 1 yr after conclusion of the program

Protein misfolding and dysregulated protein homeostasis in autoinflammatory diseases and beyond.

Cells have a number of mechanisms to maintain protein homeostasis, including proteasome-mediated degradation of ubiquitinated proteins and autophagy, a regulated process of ‘self-eating’ where the contents of entire organelles can be recycled for other uses. The unfolded protein response prevents protein overload in the secretory pathway. In the past decade, it has become clear that these fundamental cellular processes also help contain inflammation though degrading pro-inflammatory protein complexes such as the NLRP3 inflammasome. Signaling pathways such as the UPR can also be co-opted by toll-like receptor and mitochondrial reactive oxygen species signaling to induce inflammatory responses. Mutations that alter key inflammatory proteins, such as NLRP3 or TNFR1, can overcome normal protein homeostasis mechanisms, resulting in autoinflammatory diseases. Conversely, Mendelian defects in the proteasome cause protein accumulation, which can trigger interferon-dependent autoinflammatory disease. In non-Mendelian inflammatory diseases, polymorphisms in genes affecting the UPR or autophagy pathways can contribute to disease, and in diseases not formerly considered inflammatory such as neurodegenerative conditions and type 2 diabetes, there is increasing evidence that cell intrinsic or environmental alterations in protein homeostasis may contribute to pathogenesis