Prevention of upper limb symptoms and signs of nerve afflictions in computer operators: The effect of intervention by stretching

<p>Abstract</p> <p>Background</p> <p>In a previous study of computer operators we have demonstrated the relation of upper limb pain to individual and patterns of neurological findings (reduced function of muscles, sensory deviations from normal and mechanical allodynia of nerve trunks). The identified patterns were in accordance with neural afflictions at three specific locations (brachial plexus at chord level, posterior interosseous and median nerve on elbow level). We have introduced an intervention program aiming to mobilize nerves at these locations and tested its efficacy.</p> <p>Methods</p> <p>125 and 59, respectively, computer operators in two divisions of an engineering consultancy company were invited to answer a questionnaire on upper limb symptoms and to undergo a blinded neurological examination. Participants in one division were subsequently instructed to participate in an upper limb stretching course at least three times during workdays in a six month period. Subjects from the other division served as controls. At the end of the intervention both groups were invited to a second identical evaluation by questionnaire and physical examination. Symptoms and findings were studied in the right upper limb. Perceived changes of pain were recorded and individual and patterns of physical findings assessed for both groups at baseline and at follow-up. In subjects with no or minimal preceding pain we additionally studied the relation of incident pain to the summarized findings for parameters contained in the definition of nerve affliction at the three locations.</p> <p>Results</p> <p>Summarized pain was significantly reduced in the intervention group but unchanged in controls. After the intervention, fewer neurological abnormalities in accordance with nerve affliction were recorded for the whole material but no conclusion could be drawn regarding the relation to the intervention of this reduction. Incident pain correlated to findings in accordance with the three locations of nerve affliction.</p> <p>Conclusion</p> <p>A six month course of stretching seems to reduce upper limb symptoms in computer operators but we could not demonstrate an influence on neurological physical findings in this sample. The relation of incident symptoms to identified neurological patterns provides additional support to the construct validity of the employed neurological examination.</p

Impact of smoking and preoperative electrophysiology on outcome after open carpal tunnel release

Background: The aim was to evaluate the influence of smoking and preoperative electrophysiology on the outcome of open carpal tunnel release. Methods: This retrospective observational study evaluated the outcome in 493 patients (531 hands) primary operated for carpal tunnel syndrome. Data were collected from medical records, health evaluations, and QuickDASH questionnaires before surgery and 1 year after. Results: Smokers had a higher QuickDASH score preoperatively as well as postoperatively, but the change in total score did not differ. The odds of having a postoperative QuickDASH score >10 were 2.5 times higher in smoking patients than in non-smoking patients. In 124/493 patients (25%), no clinically significant improvement was seen. Normal and extreme preoperative electrophysiology values were associated with higher postoperative scores. No correlation was found between preoperative QuickDASH scores and preoperative electrophysiology values. Conclusions: Smokers with carpal tunnel syndrome experience more symptoms preoperatively. Smokers have remaining symptoms after surgery. There is no correlation between preoperative QuickDASH scores and preoperative electrophysiology values. Patients with normal or near to normal preoperative electrophysiology results have limited improvement after surgery

Outcome after carpal tunnel release : impact of factors related to metabolic syndrome

Objective: The standard surgical treatment of carpal tunnel syndrome (CTS), with an open carpal tunnel release, is reported to relieve symptoms in most patients. In a retrospective observational study, outcome after open carpal tunnel release was evaluated, focusing on factors related to the metabolic syndrome: diabetes, hypertension, obesity (BMI ≥30) and statin treatment. Methods: Results from 493 out of 962 patients (531/1044 hands) operated for CTS during 18 months that had filled in QuickDASH questionnaires before and 1-year after surgery were included in the study. Results: Patients with diabetes (n = 76) had higher QuickDASH scores pre- (56 [36–77]; i.e. median [interquartile range]) and postoperatively (31 [9–61]) compared to patients without diabetes (48 [32–66]; p 10 (74% vs 61%;

Are allergen batch differences and the use of double skin prick test important?

BACKGROUND: Skin prick tests (SPT) are widely used both in clinical diagnostics and in research. The standardization of allergen extracts is well documented to be crucial for the validity of SPT, whereas less emphasis has been placed on reproducibility and the SPT procedure itself. The objectives of this study are to clarify how the double skin prick test procedure influence the sensitivity and specificity of the test and to analyse the differences in weal size in skin prick tests between two batches of allergen extracts from the same vendor. METHODS: The association between rhinitis and SPT was assessed among 1135 persons from a general population sample. SPT was performed twice with 10 common aeroallergens. In a subsample of 90 persons SPT was performed simultaneously with five of the allergens using different batches. RESULTS: Thirty percent had at least one positive SPT. Among asthmatics this number was 62%. Only minor differences were seen between the sizes of two weals from the same batch. A second SPT with the same batch did not change the association between rhinitis and sensitization. When performing SPT with two different batches disagreement was observed in 2% (Birch) to 11% (Cat) of the subjects. CONCLUSIONS: Performing SPT twice with the same allergen batch does not enhance the validity of the test, and value of double testing can be questioned. Considerable differences in SPT response with different batches from the same manufacturer were observed. Thus inter batch differences in allergen extracts might be a source of variability

Monitoring of Anthropogenic Sediment Plumes in the Clarion-Clipperton Zone, NE Equatorial Pacific Ocean

The abyssal seafloor in the Clarion-Clipperton Zone (CCZ) in the NE Pacific hosts the largest abundance of polymetallic nodules in the deep sea and is being targeted as an area for potential deep-sea mining. During nodule mining, seafloor sediment will be brought into suspension by mining equipment, resulting in the formation of sediment plumes, which will affect benthic and pelagic life not naturally adapted to any major sediment transport and deposition events. To improve our understanding of sediment plume dispersion and to support the development of plume dispersion models in this specific deep-sea area, we conducted a small-scale, 12-hour disturbance experiment in the German exploration contract area in the CCZ using a chain dredge. Sediment plume dispersion and deposition was monitored using an array of optical and acoustic turbidity sensors and current meters placed on platforms on the seafloor, and by visual inspection of the seafloor before and after dredge deployment. We found that seafloor imagery could be used to qualitatively visualise the redeposited sediment up to a distance of 100 m from the source, and that sensors recording optical and acoustic backscatter are sensitive and adequate tools to monitor the horizontal and vertical dispersion of the generated sediment plume. Optical backscatter signals could be converted into absolute mass concentration of suspended sediment to provide quantitative data on sediment dispersion. Vertical profiles of acoustic backscatter recorded by current profilers provided qualitative insight into the vertical extent of the sediment plume. Our monitoring setup proved to be very useful for the monitoring of this small-scale experiment and can be seen as an exemplary strategy for monitoring studies of future, upscaled mining trials. We recommend that such larger trials include the use of AUVs for repeated seafloor imaging and water column plume mapping (optical and acoustical), as well as the use of in-situ particle size sensors and/or particle cameras to better constrain the effect of suspended particle aggregation on optical and acoustic backscatter signals

A cross-sectional study of the relation between symptoms and physical findings in computer operators

BACKGROUND: The character of upper limb disorder in computer operators is subject to debate. A peripheral nerve-involvement is suggested from the common presence of a triad of symptoms consisting of pain, paraestesiae and subjective weakness, and from physical findings suggesting neuropathy. This study aimed to examine the outcome of a detailed neurological examination in computer operators and to compare findings with the presence of symptoms. METHODS: 96 graphical computer operators answered a modified Nordic Questionnaire including information on perceived pain in the shoulder, elbow, and wrist/hand scored for each region on a VAS-scale 0 – 9. In addition, they underwent a physical examination including the subjective assessment of the individual function of 11 upper limb muscles, of algesia in five and vibratory threshold in three territories, respectively, and of mechanosensitivity of nerves at seven locations. In order to reflect an involvement of the brachial plexus (chord level), the posterior interosseous nerve and the median nerve at elbow level we defined three patterns of neurological findings illustrating the course of nerves and their innervation. The pain scores summarized for the three upper limb regions (min. = 0, max = 27) in the mouse-operating and contralateral limbs were compared by a Wilcoxon test and the relation to each physical item analyzed by Kendall's rank correlation. The relation of summarized pain to each pattern was studied by application of a test of the trend across ordered groups (patterns). RESULTS: Pain, paraestesiae and subjective weakness was reported for 67, 23, and 7 mouse-operating limbs, respectively, with the summarized pain scores exceeding 4 in 33 limbs. Abnormal physical findings were prevalent. The summarized pain was significantly related to a reduced function in five muscles, to mechanical allodynia at one location and to elevated threshold to vibration in two territories. Brachial plexopathy was diagnosed in 9/2, median neuropathy in 13/5 and posterior interosseous neuropathy in 13/8 mouse operating/contralateral limbs, respectively. The summarized pain was significantly higher in the mouse-operating limbs and in limbs with any of the defined patterns. There was a significant trend between the summarized pain and the summarized scores for the items contained in each pattern. CONCLUSION: This small-scale study of a group of computer-operators currently in work and with no or minor upper limb symptoms has indicated in symptomatic subjects the presence of peripheral nerve-afflictions with specific locations