Abstracts of current literature

S OF CURRENT LITERATURE / 129 ABSTRACTS OF CURRENT LITERATURE Lee LJ, Coppieters MW, Hodges PW. Differential activation of the thoracic multifidus and longissimus thoracis during trunk rotation. Spine 2005;30:870-876. Abstract: Study Design: Cross-sectional study. Objective: To develop a technique to measure electromyographic (EMG) activity of deep and superficial paraspinal muscles at different thoracic levels and to investigate activity of these muscles during seated trunk rotation. Summary of Background Data: Few studies have compared activity of deep and superficial paraspinal muscles of the thorax during trunk rotation, and conflicting results have been presented. Conflicting data may result from recording techniques or variation in activity between thoracic regions. Methods: EMG recordings were made from deep (multifidus/rotatores) and superficial (longissimus) paraspinal muscles at T5, T8, and T11 using selective intramuscular electrodes. Ten subjects rotated the trunk to end of range in each direction. EMG amplitude was measured in neutral, at end of range, and during four epochs, which represented four quarters of the movement. Results: During trunk rotation in sitting, longissimus EMG either increased with ipsilateral rotation (T5) or decreased with contralateral rotation (T5, T8, T11). In contrast, multifidus EMG was more variable and was either active with rotation in both directions (particularly T5) or with one movement direction. Conclusions: The deep and superficial muscles of the thorax are differentially active, and the patterns of activity differ between the regions of the thorax. Data from this study support the hypothesis that multifidus may have a role in control of segmental motion at T5. Variability in multifidus activity at T8 and T11 suggests that this muscle may also control coupling between rotation and lateral flexion. Study Design: Cross-sectional study. Objective: To develop a technique to measure electromyographic (EMG) activity of deep and superficial paraspinal muscles at different thoracic levels and to investigate activity of these muscles during seated trunk rotation. Summary of Background Data: Few studies have compared activity of deep and superficial paraspinal muscles of the thorax during trunk rotation, and conflicting results have been presented. Conflicting data may result from recording techniques or variation in activity between thoracic regions. Methods: EMG recordings were made from deep (multifidus/rotatores) and superficial (longissimus) paraspinal muscles at T5, T8, and T11 using selective intramuscular electrodes. Ten subjects rotated the trunk to end of range in each direction. EMG amplitude was measured in neutral, at end of range, and during four epochs, which represented four quarters of the movement. Results: During trunk rotation in sitting, longissimus EMG either increased with ipsilateral rotation (T5) or decreased with contralateral rotation (T5, T8, T11). In contrast, multifidus EMG was more variable and was either active with rotation in both directions (particularly T5) or with one movement direction. Conclusions: The deep and superficial muscles of the thorax are differentially active, and the patterns of activity differ between the regions of the thorax. Data from this study support the hypothesis that multifidus may have a role in control of segmental motion at T5. Variability in multifidus activity at T8 and T11 suggests that this muscle may also control coupling between rotation and lateral flexion. Bey MJ, Hunter SA, Kilambi N, Butler DL, Lindenfeld TN. Structural and mechanical properties of the glenohumeral joint posterior capsule. J Shoulder Elbow Surg 2005;14:201-206. The purpose of this study was to quantify regional variations in material properties of the glenohumeral joint posterior capsule and to compare these data with the anterior band of the inferior glenohumeral ligament (AB-IGHL). Mechanical properties were determined for individual bands of the AB-IGHL, superior posterior capsule (SUP-PC), middle posterior capsule (MID-PC), and inferior posterior capsule (INF-PC). Significant differences in tissue thickness were found among the 3 posterior capsular regions and the AB-IGHL. The AB-IGHL was thicker than the MID-PC (P = .03) and INF-PC (P = .01), and the SUP-PC was thicker than the INF-PC (P = .02). Except for significant differences in failure strains, material properties were not significantly different among the 4 tissue regions. There were no significant differences between tissue bands in modulus (P = .2), maximum stress (P = .46), or strain energy density (P = .62). Specimens failed primarily near the glenoid insertion (75%), with 4 specimens failing at the humeral insertion and 2 others failing in the tissue’s mid substance. Nilsson-Wikmar L, Holm K, Oijerstedt R, HarmsRingdahl K. Effect of three different physical therapy treatments on pain and activity in pregnant women with pelvic girdle pain: a randomized clinical trial with 3, 6, and 12 months follow-up postpartum. Spine 2005;30:850-856. Abstract: Study Design: A randomized assessor-blinded clinical trial was conducted. Objective: To compare 3 different physical therapy treatments with respect to pain and activity in women with pelvic girdle pain during pregnancy and 3, 6, and 12 months postpartum. Summary of Background Data: In spite of the high prevalence of back pain during pregnancy, documented treatment programs are limited. Methods: Based on a clinical examination, 118 women with pelvic girdle pain diagnosed during pregnancy were randomized into 3 different treatment groups: Information Group, use of a non-elastic sacroiliac belt and oral/written information about pelvic girdle pain (n = 40); Home Exercise Group, same as in the Information Group, with the addition of a home exercise program (n = 41); and the In Clinic Study Design: A randomized assessor-blinded clinical trial was conducted. Objective: To compare 3 different physical therapy treatments with respect to pain and activity in women with pelvic girdle pain during pregnancy and 3, 6, and 12 months postpartum. Summary of Background Data: In spite of the high prevalence of back pain during pregnancy, documented treatment programs are limited. Methods: Based on a clinical examination, 118 women with pelvic girdle pain diagnosed during pregnancy were randomized into 3 different treatment groups: Information Group, use of a non-elastic sacroiliac belt and oral/written information about pelvic girdle pain (n = 40); Home Exercise Group, same as in the Information Group, with the addition of a home exercise program (n = 41); and the In Clinic The Journal of Manual & Manipulative Therapy Vol. 13 No. 2 (2005), 129 130 130 / The Journal of Manual & Manipulative Therapy, 2005 Exercise Group, same as in the Information Group, plus participation in a training program (n = 37). Pain intensity was rated on a visual analogue scale (0-100 mm) and marked on a pain drawing concerning localization. The activity ability was scored using the Disability Rating Index, covering 12 daily activity items. Outcome measures were obtained at inclusion, on average in gestation week 38, and 3, 6, and 12 months postpartum. Results: There was no significant difference among the 3 groups during pregnancy or at the follow-ups postpartum regarding pain and activity. In all groups, pain decreased and the activity ability increased between gestation week 38 and at 12 months postpartum. Conclusions: Women with pelvic girdle pain seemed to improve with time in all 3 treatment groups. Neither home nor in clinic exercises had any additional value above giving a non-elastic sacroiliac belt and information. McAviney J, Schulz D, Bock R, Harrison DE, Holland B. Determining the Relationship Between Cervical Lordosis and Neck Complaints. J Manipulative Physiol Ther 2005;28:187-193. Objective: To investigate the presence of a “functionally normal” cervical lordosis and identify if this and the amount of forward head posture are related to neck complaints. Methods: Using the posterior tangent method, an angle of cervical lordosis was measured from C2 through C7 vertebrae on 277 lateral cervical x-rays. Anterior weight bearing was measured as the horizontal distance of the posterior superior body of the C2 vertebra compared to a vertical line drawn superiorly from the posterior inferior body of the C7 vertebra. The measurements were sorted into 2 groups, cervical complaint and non-cervical complaint groups. The data were then partitioned into age by decades, sex, and angle categories. Results: Patients with lordosis of 20° or less were more likely to have cervicogenic symptoms (P < .001). The association between cervical pain and lordosis of 0° or less was significant (P < .0001). The odds that a patient with cervical pain had a lordosis of 0° or less was 18 times greater than for a patient with a non-cervical complaint. Patients with cervical pain had less lordosis and this was consistent over all age ranges. Males had larger median cervical lordosis than females (20° vs. 14°) (2-sided Mann-Whitney U test, P = .016). When partitioned by age grouping, this trend is significant only in the 40to 49-year-old range (2-sided Mann-Whitney U test, P < .01). Conclusion: We found a statistically significant association between cervical pain and lordosis <20° and a “clinically normal” range for cervical lordosis of 31° to 40°. Maintenance of a lordosis in the range of 31° to 40° could be a clinical goal for chiropractic treatment. Nicklas BJ, You T, Pahor, M. Behavioural treatments for chronic systemic inflammation: effects of dietary weight loss and exercise training. CMAJ 2005; 172:1199-1209. Persistent low-grade inflammation, as indicated by higher circulating levels of inflammatory mediators such as Creactive protein, interleukin-6 and tumor necrosis factor-α, is a strong risk factor for several chronic diseases. There are data indicating that decreasing ener