Anders Ingemann Larsen

Manual strength testing in 14 upper limb muscles A study of inter-rater reliability

Background Manual muscle testing has been termed a “lost art” and is often considered to be of minor value. The aim of this investigation was to study the inter-rater reliability of manual examination of the maximal voluntary strength in a sample of upper limb muscles. Patients and methods The material consisted of a series of 41 consecutive patients (82 limbs) who had been referred to a clinic of occupational medicine for various reasons. Two examiners who were blinded as to patient-related information classified 14 muscles in terms of normal or reduced strength. In order to optimize the evaluation, the individual strength was assessed simultaneously on the right and left sides with the limbs in standardized positions that were specific for each muscle. Information on upper limb complaints (pain, weakness and/or numbness/tingling) collected by two other examiners resulted in 38 limbs being classified as symptomatic and 44 as asymptomatic. For each muscle the inter-rater reliability of the assessment of strength into normal or reduced was estimated by κ-statistics. In addition, the odds ratio for the relation to symptoms of the definition in agreement of strength was calculated. Results The median κ-value for strength in the muscles examined was 0.54 (0.25–0.72). With a median odds ratio of 4.0 (2.5–7.7), reduced strength was significantly associated with the presence of symptoms. Interpretation This study suggests that manual muscle testing in upper limb disorders has diagnostic potential.

Diagnostic accuracy of the neurological upper limb examination II: Relation to symptoms of patterns of findings

BackgroundIn a sample of patients in clinical occupational medicine we have demonstrated that an upper limb neurological examination can reliably identify patterns of findings suggesting upper limb focal neuropathies. This further study aimed at approaching the diagnostic accuracy of the examination.Methods82 limbs were semi-quantitatively assessed by two blinded examiners (strength in 14 individual muscles, sensibility in 7 homonymous territories, and mechanosensitivity at 10 locations along nerves). Based on the topography of nerves and their muscular and sensory innervation we defined 10 neurological patterns each suggesting a localized nerve affliction. Information on complaints (pain, weakness and/or numbness/tingling) collected by others served as a reference for comparison. The relation between the presence of pattern(s) and complaints was assessed by κ-statistics. Sensitivity, specificity, and positive/negative predictive values were calculated, and pre-test odds were compared to post-test probability.ResultsThe two examiners identified pattern(s) suggesting focal neuropathy in 34/36 out of 38 symptomatic limbs, respectively (κ = 0.70/0.75), with agreement in 28 limbs. Out of 44 non-symptomatic limbs the examiners agreed on absence of any pattern in 38 limbs. With concordance between the examiners with regard to the presence or absence of any pattern, the sensitivity, specificity, positive and negative predictive values were 0.73, 0.86, 0.93 and 0.90, respectively. While the pre-test odds for a limb to be symptomatic amounted to 0.46 the post-test probability was 0.81. For each examiner the post-test probability was 0.87 and 0.88, respectively.ConclusionThe improved diagnostic confidence is an indication of one aspect of construct validity of the physical examination. For determination of clinical feasibility of the examination further studies are required, most importantly 1) studies of validity by means of comparison with additional references and 2) studies of the potential benefit that can be attained from its use.

Contact allergy to the fungicide benomyl

Benomyl is a widely used fungicide. Contact allergy to benomyl has been reported in a few cases. We describe a group of 62 workers, exposed to benomyl. None had contact dermatitis from benomyl. It appears that benomyl at most is a weak sensitizer. We suggest that earlier‐reported allergy may represent cross‐reactions and/or that the development of contact allergy to benomyl requires previous exposure to other chemically related pesticides.

Allergic contact dermatitis from thiamine.

Case no. 1. A 54-year-old nonatopic former grocer, employed in a pharmaceutical plant, filled and packed thiamine hydrochloride in a dusty process. After I month, he developed an itchy eczema on the forearms and dorsa of the hands, with some spread to the face. His condition did not improve with plastic gloves over most of the affected areas of the upper limbs, but disappeared on treatment with budesonide cream and 3 weeks off work. A severe flare-up followed immediately after resuming work, and he had to stop any work in contact with thiamine. He had had no recent oral intake of thiamine. Patch tests with thiamine 10%, 5% and I% aq. and thiothiamine 5% and I% aq. were applied with Finn Chambers® and read at 48 and 72 h, showing positive reactions to thiamine 10% and 5% aq.: thiamine I% aq. showed erythema only. Positive reactions were also recorded to thiothiamine 5% and 1% aq. A positive reaction was found to the inside of the used, but not the new, gloves. Testing with the European standard series was negative.

Lasting effects of workplace strength training for neck/shoulder/arm pain among laboratory technicians: natural experiment with 3-year follow-up

Objectives. This study investigated long-term effects and implementation processes of workplace strength training for musculoskeletal disorders. Methods. 333 and 140 laboratory technicians from private and public sector companies, respectively, replied to a 3-year follow-up questionnaire subsequent to a 1-year randomized controlled trial (RCT) with high-intensity strength training for prevention and treatment of neck, shoulder, and arm pain. Being a natural experiment, the two participating companies implemented and modified the initial training program in different ways during the subsequent 2 years after the RCT. Results. At 3-year follow-up the pain reduction in neck, shoulder, elbow, and wrist achieved during the first year was largely maintained at both companies. However, the private sector company was rated significantly better than the public sector company in (1) training adherence, (2) training culture, that is, relatively more employees trained at the workplace and with colleagues, (3) self-reported health changes, and (4) prevention of neck and wrist pain development among initially pain-free employees. Conclusions. This natural experiment shows that strength training can be implemented successfully at different companies during working hours on a long-term basis with lasting effects on pain in neck, shoulder, and arm.

Neurological Examination of the Upper Limb: A Study of Construct Validity

Objective: We have previously demonstrated that neurological individual findings and patterns can be reliably assessed in the examination of the upper limb and also that they are related to pain, weakness, and/or numbness/tingling. This study aimed to study further aspects of the construct validity of the neurological examination. Methods: Blinded to patient-characteristics, two examiners assessed the function of 16 muscles, the sensibility in 7 territories, and the nerve-mechanosensitivity at 20 locations in 82 upper limbs. Based on anatomical patterns and pre-designed algorithms, one or both examiners rated neuropathy as “possible” or “definite” in 40 limbs and also determined the location( s). We developed and tested hypotheses on anatomically and regionally related locations of nerve afflictions (a selective vulnerability of neurons, double and multiple crush, and a tendency to regional spread) and examined the stability of the internal structure of the constructs in different situations. The interrelations of findings were analyzed by hypothesis testing and factor analyses, and the homogeneity of location profiles was analyzed by a conditional likelihood test. Results: Out of 30 limbs with related locations of neuropathy, the findings of each examiner correlated positively (gamma > 0.35) in 22/25, respectively. The patterns of the interrelations identified by the two examiners were similar, with no evidence of any heterogeneity of location profiles for either examiner. Conclusions: This study supports the validity of the physical examination. However, feasibility of its application requires the demonstration of further aspects of construct validity and a favorable influence on patient-management and/or prevention.

Practical occupational medicine in "practice"

In Denmark, the practice of occupational medicine tends to be carried out by specialists in occupational medicine and less so by family physicians. The provision of health service to workers is therefore limited. This constraint may also apply in other developed countries and even more in countries with few occupational health resources. This Editorial argues that family physicians are indeed in a position where they can make a major positive difference for their working patients and for the enterprises where they work. Without specialist knowledge in occupational medicine, the family physician’s empiric knowledge in combination with a narrative approach to the patient permits the contribution from family medicine not only with regard to diagnosis and treatment, but also relating to actions targeted to optimize the patient’s future accommodation at work as well as to protect other similarly exposed workers. Such involvement would expand the coverage of occupational health service to patients/workers on a global scale.

Increased pancreas cancer in a bio­technological research laboratory

BACKGROUND Pancreatic cancer is extremely rare among people under 55 years old. Its prognosis is poor, and the causal background remains almost unresolved. A previous study observed an increased occurrence of pancreatic cancer in workers in a French biochemical laboratory. METHODS CASE REPORT During an approximate 10 year period in a Danish bio-chemical laboratory with about 50 stable employees, four cases of pancreatic cancer have been diagnosed at a mean age of 53 years. Approximately 0.02 cases should be expected if the laboratory employees had experienced the same rate of pancreatic cancer as that observed in the respective general Danish populations. RESULT All the four cases had a long-term occupational history of exposure to carcinogens during the early bio-technology period. CONCLUSIONS Causal conclusions cannot be made yet, but observation of former and present workers in biotechnological laboratories and their cancer occurrence is warranted.