No abstract

A number of treatments are widely prescribed for chronic back pain, but few have been rigorously evaluated. We examined the effectiveness of transcutaneous electrical nerve stimulation (TENS), a program of stretching exercises, or a combination of both for low back pain. Patients with chronic low back pain (median duration, 4.1 years) were randomly assigned to receive daily treatment with TENS (n = 36), sham TENS (n = 36), TENS plus a program of exercises (n = 37), or sham TENS plus exercises (n = 36). After one month no clinically or statistically significant treatment effect of TENS was found on any of 11 indicators of outcome measuring pain, function, and back flexion; there was no interactive effect of TENS with exercise. Overall improvement in pain indicators was 47 percent with TENS and 42 percent with sham TENS (P not significant). The 95 percent confidence intervals for group differences excluded a major clinical benefit of TENS for most outcomes. By contrast, after one month patients in the exercise groups had significant improvement in self-rated pain scores, reduction in the frequency of pain, and greater levels of activity as compared with patients in the groups that did not exercise. The mean reported improvement in pain scores was 52 percent in the exercise groups and 37 percent in the nonexercise groups (P = 0.02). Two months after the active intervention, however, most patients had discontinued the exercises, and the initial improvements were gone. We conclude that for patients with chronic low back pain, treatment with TENS is no more effective than treatment with a placebo, and TENS adds no apparent benefit to that of exercise alone.

No abstract

This double-blind, randomized study was designed to compare the effectiveness of intravenous regional sympatholysis using guanethidine, reserpine and normal saline. Twenty-one patients with reflex sympathetic dystrophy of an upper or lower extremity were enrolled and received intravenous regional blockade (IVRB) with one of the three medications. There was significant pain relief in all three groups at 30 min. There were no significant differences among the three groups in the degree of pain relief, the number of patients obtaining pain relief in the 30 min after the block, or the number of patients reporting more than 50% pain relief for more than 24 hr. The saline group's high rate of pain relief could be partially due to a mechanism of tourniquet-induced analgesia.

This double-blind, randomized, multicenter study was designed to determine the short-term and long-term efficacy of intravenous regional block with guanethidine in patients with reflex sympathetic dystrophy (RSD)/causalgia. Sixty patients were enrolled to receive four intravenous regional blocks at 4-day intervals with either guanethidine or placebo in 0.5% lidocaine. Each patient was randomized to receive either one, two, or four blocks with guanethidine. Follow-up visits were scheduled for 4 days, 1 mo, 3 mo, and 6 mo after their final block. At 4 days after the initial block, the group treated with placebo experienced a greater decrease in pain scores than those treated with guanethidine, although this difference was not statistically significant. On long-term followup there was no difference in pain scores between groups receiving one, two, or four guanethidine blocks. Overall, only 35% of patients experienced clinically significant relief on long-term followup even though all were treated early in the evolution of RSD.

No abstract

The present study compares the effectiveness of 0.25% ropivacaine and 0.25% bupivacaine in 44 patients receiving a subclavian perivascular brachial plexus block for upper extremity surgery. The patients were assigned to two equal groups in this randomized, double-blind study; one group received ropivacaine 0.25% (112.5 mg) and the other, bupivacaine 0.25% (112.5 mg), both without epinephrine. Onset times for analgesia and anesthesia in each of the C-5 through T-1 brachial plexus dermatomes did not differ significantly between the two groups. The mean onset time for analgesia ranged from 11.2 to 20.2 min, and the mean onset time for anesthesia ranged from 23.3 to 48.2 min. The onset of motor block differed only with respect to paresis in the hand, with bupivacaine demonstrating a shorter onset time than ropivacaine. The duration of sensory and motor block also was not significantly different between the two groups. The mean duration of analgesia ranged from 9.2 to 13.0 h, and the mean duration of anesthesia ranged from 5.0 to 10.2 h. Both groups required supplementation with peripheral nerve blocks or general anesthesia in a large number of cases, with 9 of the 22 patients in the bupivacaine group and 8 of the 22 patients in the ropivacaine group requiring supplementation to allow surgery to begin. In view of the frequent need for supplementation noted with both 0.25% ropivacaine and 0.25% bupivacaine, we do not recommend using the 0.25% concentrations of these local anesthetics to provide brachial plexus block.

No abstract