Enhancing the examiner's resisting force improves the validity of manual muscle strength measurements: application to knee extensors and flexors.

The purposes of this study were to test whether an examiner's strength may affect the validity of the knee muscle strength measurements using a hand-held dynamometer (HHD) and whether enhancing the forces applied by an examiner using a resistance-enhanced dynamometer (RED) would improve measurement validity. Twenty-five young male volunteers (mean [±SD] age: 22.5 ± 1.7 years) without a history of injury to the test limb and 6 male and 6 female experienced examiners participated in this study. Maximum resisting forces of the knee flexors and extensors were measured using RED, HHD, and a dynamometer (Kin-Com). For all testing conditions, poor to moderate associations were found between the HHD and Kin-Com, whereas there was a good to excellent relationship between RED and Kin-Com. The systematic variations between RED and Kin-Com were also smaller than those between HHD and Kin-Com. The force values measured by RED were very close to those measured by Kin-Com. An examiner's strength affects the validity of the measurements using HHD. Enhancing the forces applied by the examiner to the tested segment using RED appeared to improve the validity of muscle strength measurements.

Enhancing the examiner's resisting force improves the reliability of manual muscle strength measurements: comparison of a new device with hand-held dynamometry.

OBJECTIVE: To develop and determine the reliability of a newly -designed resistance-enhanced dynamometer for muscle strength measurement, and to test the hypothesis that enhancing the examiner's resisting force improves the reliability of manual muscle strength measurements. DESIGN: An intra-examiner, inter-examiner, intra-session and inter-session reliability study. SUBJECTS: Twenty-five men (mean age 22.5 (standard deviation (SD) 1.7) years) were tested separately by 2 examiners using the resistance-enhanced dynamometer and a traditional hand-held dynamometer for an intra- and inter-examiner reliability study. Twenty-seven volunteers (mean age 22.1 (SD 0.8) years) were tested by a female examiner using the resistance-enhanced dynamometer for an intra- and inter-session reliability study. METHODS: Maximum resisting forces for the knee flexors and extensors were measured using the resistance-enhanced dynamometer and the traditional hand-held dynamometer. RESULTS: The traditional hand-held dynamometer had good intra-examiner reliability (intra-class correlation coefficient (ICC) = 0.79-0.93) but poor inter-examiner reliability (ICC = 0.11-0.28). The resistance-enhanced dynamo meter had very good intra-examiner (ICC = 0.91-0.94), inter-examiner (ICC = 0.98), intra-session (ICC = 0.93-0.99) and inter-session (ICC = 0.91-0.92) reliability. The resistance-enhanced dynamometer also had better inter-examiner agreement (smallest real difference (SRD) 9-16% for resistance-enhanced dynamometer, 21-43% for traditional hand-held dynamometer). CONCLUSION: The resistance-enhanced dynamometer had very good reliability. Enhancing the examiner's resisting force appeared to improve the reliability of manual muscle strength measurements. The resistance-enhanced dynamometer is useful for muscle strength measurements in clinical practice.

Inhibition of tobacco smoke-induced lung inflammation by a catalytic antioxidant.

Cigarette smokers experience airway inflammation and epithelial damage, the mechanisms of which are unknown. One potential cause may be free radicals either in tobacco smoke or produced during persistent inflammation. Inflammation may also be a driving force to cause airway epithelium to undergo changes leading to squamous cell metaplasia. To test whether tobacco smoke-induced inflammation could be reduced by a catalytic antioxidant, manganese(III)meso-tetrakis(N,N'-diethyl-1,3-imidazolium-2-yl) porphyrin (AEOL 10150) was given by intratracheal instillation to rats exposed to filtered air or tobacco smoke. Exposure to tobacco smoke for 2 d or 8 weeks (6 h/d, 3 d/week) significantly increased the number of cells recovered by bronchoalveolar lavage (BAL). AEOL 10150 significantly decreased BAL cell number in tobacco smoke-treated rats. Significant reductions in neutrophils were noted at 2 d and macrophages at 8 weeks. Lymphocytes were significantly reduced by AEOL 10150 at both time points. Squamous cell metaplasia following 8 weeks of tobacco smoke exposure was 12% of the total airway epithelial area in animals exposed to tobacco smoke without AEOL 10150, compared with 2% in animals exposed to tobacco smoke, but treated with AEOL 10150 (p <.05). We conclude that a synthetic catalytic antioxidant decreased the adverse effects of exposure to tobacco smoke.