Study Design: Cross-sectional study of isokinetic trunk and knee muscle strength in women who are obese.

Objective:To provide reference values, to identify variables that affect peripheral muscle strength, and to provide recommendations for isokinetic testing of trunk and knee muscles in women who are obese and morbidly obese.

Background: The assessment of peripheral muscle strength is useful for the quantification of possible loss of strength, for exercise prescription, and for the evaluation of the effect of training programs in obese individuals.

Methods and Measures: Isokinetic trunk and leg muscle strength was assessed in 241 women who were obese (18–65 years, body mass index (BMI) = 30 kg/m2). Trunk flexion and extension peak torque (PT) were measured using the Cybex TEF dynamometer; trunk rotation (TR) PT was measured using the Cybex TORSO dynamometer; and knee flexion/extension (KFE) PT was measured using the Cybex 350 dynamometer. Body composition was assessed using the bioelectrical impedance method; physical activity was assessed using the Baecke questionnaire; and peak VO2 was assessed using an incremental exercise capacity test on a bicycle ergometer. To identify variables related to muscle strength, Pearson correlations were computed and a stepwise multiple regression analysis was performed.

Results: Pearson correlation coefficients of all strength measurements at 60°/s revealed low-to-moderate negative associations with age and positive associations with mass, height, fat free mass (FFM), and peak VO2 (P < 0.05), except for gravity-uncorrected trunk extension strength, which was not related to mass. The sports index of the Baecke questionnaire was associated with TR PT (r = 0.20, P < 0.01) and KFE PT (r = 0.18, P < 0.05).

Conclusion: The weight of the trunk accounts largely for the measured trunk extensor and flexor strength in women who are obese. Contributing variables of isokinetic trunk flexion and extension strength in women who are obese are age, height, and FFM; whereas sports activities and aerobic fitness are contributing factors for trunk rotational and knee extension strength. Recommendations for measuring isokinetic muscle strength in individuals who are obese are provided.

J Orthop Sports Phys Ther. 2002; 32(7):347–356.

Key Words: isokinetic muscle strength, obesity, reference values, women

Study Design: Repeated measures design of active spinal position sense in individuals with and without low back pain (LBP).

Objectives: Reproducibility and validity evaluation of thoracolumbar proprioception measurement.

Background: Proprioception studies in peripheral joints and the spine suggest that there may be proprioception deficits due to injury, pain, or degeneration. Kinesthetic retraining may be useful in rehabilitation of patients with LBP, but appropriate measures are required to quantify spinal proprioception objectively.

Methods and Measures: Active-target reproduction in the sagittal, horizontal, and coronal planes was assessed (3 separate occasions for 18 asymptomatic volunteers and 2 occasions for 62 patients with LBP). Repositioning accuracy was expressed as absolute errors (AE) and variable errors (VE). Reliability was analyzed with intraclass correlation coefficient (ICC) and precision with standard error of measurement (SEM) and calculation of the smallest detectable difference (SDD) index. Repeated measures ANOVA and correlations were used for within-group comparisons and discriminant analysis for between-group comparisons.

Results: Reproducibility was better for the asymptomatic group, with AE for flexion and rotation being the most reliable (ICC = 0.76–0.80, SEM = 0.91°–1.34°). SDDs were high for all tests, suggesting limited clinical applicability. Reproducibility for the same tests was poor-moderate (ICC = 0.31–0.64, SEM = 0.45°–3.90°) for the patient group. AE for right-side rotation could discriminate between subject groups with 83.3% specificity but only 54.8% sensitivity.

Conclusions: Proprioception testing, with the methods employed, did not demonstrate good measurement properties in a sample of patients with recurrent LBP. Neither could it sufficiently discriminate between individuals with and without LBP. Possible reasons for these findings are discussed.

J Orthop Sports Phys Ther. 2002; 32(7):327–335.

Key Words: electrogoniometer, muscle spindle, neuromuscular dysfunction, position sense

As a clinician treating musculoskeletal conditions, one is continually in search of safe and more effective treatment methods that will hasten tissue healing. Chronic inflammation has been shown to cause connective tissue degradation. Typically, nonsteroidal anti-inflammatory drugs (NSAIDs) and/or corticosteroids are used to control the inflammatory process, however, long-term use has been associated with potentially serious side effects. The purpose of this article is to introduce and describe literature on 2 natural compounds, namely, proanthocyanidin (PCO) and quercetin, which are 2 specific types of bioflavonoids, and to discuss their potential benefits in treating musculoskeletal conditions. There is evidence to suggest that flavonoids may be beneficial to connective tissue for several reasons, which include the limiting of inflammation and associated tissue degradation, the improvement of local circulation, as well as the promoting of a strong collagen matrix. An overview of bioflavonoids as well as relevant research, safety issues, absorption, and specific sources of PCO and quercetin in foods and through supplementation is included.

J Orthop Sports Phys Ther. 2002; 32(7):357–363.

Key Words: connective tissue, inflammation, proteolytic enzymes