Specific trunk and general exercise elicit similar changes in anticipatory postural adjustments in patients with chronic low back pain : a randomized controlled trial

Study Design. A randomized controlled trial. Objective. To compare changes in self-rated disability, pain, and anticipatory postural adjustments between specific trunk exercise and general exercise in patients with chronic low back pain. Summary of Background Data. Chronic low back pain is associated with altered motor control of the trunk muscles. The best exercise to address altered motor control is unclear. Methods. Sixty-four patients with chronic low back pain were randomly assigned to a specific trunk exercise group (SEG) that included skilled cognitive activation of the trunk muscles in addition to a number of other best practice exercises, whereas the general exercise group performed only seated cycling exercise. The training program lasted for 8 weeks. Self-rated disability and pain scores were collected before and after the training period. Electromyographic activity of various trunk muscles was recorded during performance of a rapid shoulder flexion task before and after training. Muscle onsets were calculated, and the latency time (in ms) between the onset of each trunk muscle and the anterior deltoid formed the basis of the motor control analysis. Results. After training, disability was significantly lower in the SEG (d = 0.62, P = 0.018). Pain was reduced in both groups after training (P < 0.05), but was lower for the SEG (P < 0.05). Despite the general exercise group performing no specific trunk exercise, similar changes in trunk muscle onsets were observed in both groups after training. Conclusion. SEG elicited significant reductions in self-rated disability and pain, whereas similar between-group changes in trunk muscle onsets were observed. The motor control adaptation seems to reflect a strategy of improved coordination between the trunk muscles with the unilateral shoulder movement. Trunk muscle onsets during rapid limb movement do not seem to be a valid mechanism of action for specific trunk exercise rehabilitation programs

Pilates exercise or stationary cycling for chronic nonspecific low back pain : does it matter? : a randomized controlled trial with 6-month follow-up

Study Design.: Randomized controlled trial. Objective.: This is the companion study to a previous publication that presented 8-week pain, disability, and trunk muscle motor control results. The objective of this study was to compare the effect of 8 weeks of specific trunk exercises and stationary cycling on outcomes measures of catastrophizing and fear-avoidance beliefs (FAB) in patients with chronic nonspecific low back pain, and provide 6-month outcome data for all self-report measures. Summary of Background Data.: It is thought that any form of moderate-to-vigorous physical activity is sufficient to address catastrophizing and FAB, and concomitant levels of pain and disability. Methods.: Sixty-four patients with low back pain were randomly assigned to 8 weeks of specific trunk exercise group (SEG), or stationary cycling group (CEG). Self-rated pain, disability, catastrophizing and FAB scores were collected before, immediately after (8 wk), and 6 months after the training program. Clinically meaningful improvements were defined as greater than a 30% reduction from baseline in pain and disability scores. "Intention-to-treat" principles were used for missing data. Per-protocol analysis was performed on participants who attended at least two-thirds of the exercise sessions. Results.: At 8 weeks, disability was significantly lower in the SEG compared with the CEG (d = 0.62, P = 0.018). Pain was reduced from baseline in both the groups after training (P < 0.05), but was lower for the SEG (P < 0.05). FAB scores were reduced in the SEG at 8 weeks, and in the CEG at 6 months. No between-group differences in FAB scores were observed. Similar reductions in catastrophizing in each group were observed at each time point. At 6 months, the overall data pattern suggested no long-term difference between groups. Per-protocol analysis of clinically meaningful improvements suggests no between-group differences for how many patients are likely to report improvement. Conclusion.: Inferential statistics suggest greater improvements at 8 weeks, but not 6 months, for the SEG. Inspection of clinically meaningful changes based on a minimum level of adherence suggests no between-group differences. If a patient with low back pain adheres to either specific trunk exercises or stationary cycling, it is reasonable to think that similar improvements will be achieved