"The available evidence neither supports nor refutes that advice to stay active is better than resting in bed for people with sciatica," Dahm said. "However, considering that bed rest is associated with potential harmful side effects, we think it is reasonable to advise people with sciatica to stay active."
In general, Press said, "we're almost always better moving than not moving. Structures in your back get their nutrition from movement; they have no real vascular system and are supplied with blood by motion, soaking it up like little sponges."
Negative changes associated with immobility "manifest right away," he said. Studies done in the 1950s showed that people lose 2 percent to 5 percent of their strength per day of complete bed rest.
The reviewers also compared bed rest and activity with other treatments. Pooled data of three studies including 931 low-back pain patients found little or no difference in pain or ability to function between patients on bed rest and those prescribed exercises.
Similarly, results of a single trial with 186 patients suggested that "exercises add no clinically relevant benefit for patients with acute low-back pain when compared to advice to stay active," the authors wrote.
They came to the same conclusion about physiotherapy compared to either bed rest or activity for sciatica, from a single study involving 167 patients.
Press emphasized the need for future research to categorize back pain more precisely. "Not all back pain is the same; there are lots of different causes," and the chances of finding a single treatment to benefit all patients are not good, he said. The goal should be defining subgroups "so we can predict from symptoms, physical examination and imaging studies which patients will respond to which types of treatment."
SOURCE The Cochrane Library