Effect of postural angle on back muscle activities in aging female workers performing computer tasks

[Purpose] This study investigated the effects of postural angle on back muscle activity during a computer task in aging women. [Subjects] Seventeen women ≥50 years old participated. [Methods] The participants were instructed to perform computer-related tasks for 20 minutes on a workstation that simulated typical office working conditions. Back posture was measured from the measured trunk and pelvic angles. Electromyography activities were recorded simultaneously from the cervical erector spinae, longissimus, and multifidus muscles. [Results] The lowest mean percentages of maximum voluntary contraction for the cervical erector spinae and longissimus muscles were obtained when the upper trunk and pelvic angles were between 0° to −5° from the sagittal plane. The back muscle activities increased as the upper trunk and pelvic angles exceeded 0°. Statistical analysis showed significant correlations between upper trunk angle and cervical erector spinae and longissimus muscle activities. Similarly, pelvic angle was significantly correlated with cervical erector spinae and multifidus muscle activities. [Conclusion] A neutral back posture minimizes muscle activities in aging women performing computer tasks.Key words: Postural angle, Muscle activity, Aging     

A case of polymicrobial endocarditis due to anaerobic organisms in an injection drug user

Endocarditis is a serious complication of injection drug use most commonly due to Staphylococcus aureus. We report a case of tricuspid valve polymicrobial bacterial endocarditis in an injection drug user from 3 oral anaerobes: Actinomyces odontolytica, Veilloenlla species, and Prevotella melaninogenica. The patient was believed to have acquired these organisms due to his habit of licking the needle in order to gauge the strength of the cocaine prior to injection. The patient was successfully treated with a 6-week course of penicillin G and metronidazole. This case demonstrates the importance of a detailed history in designing empiric therapy. The authors have no conflicts of interest to declare for this case study or this research. This case study was presented as a poster at the 27th Annual SGIM Meeting, May 12–15; 2004.