A randomized control trial was done for low back pain and sciatica that studied the effect of different directional exercises and determined whether a single direction of movement (called a "directional preference) could be found to reduce or eliminate lower back pain &/or sciatica. Those that found relief with an exercise done in a certain direction were split into groups. One group exercised in the direction of their "directional preference", a second group exercised in the opposite of their "directional preference", and a third group exercised in a non-directional exercise. The measured outcomes included pain intensity, location, disability, medication use, degree of recover, depression and work interference.
The group that exercised in their directional preference direction had significantly greater improvements in all outcomes, compared to the other two groups, including a three-fold improvement decrease in medication use. Regardless whether a participants "directional preference was flexion, extension or lateral movement, the results of doing the exercise in their directional preference their pain significantly and rapidly decreased pain and medication use and improved all other outcomes. These findings are consistent with other research on "directional preference" exercises for low back pain and sciatica.
I've Done Exercise in Physical Therapy Before, but They Didn't Help...
Research indicates that repetitively exercising in a single direction that has been shown to reduce or eliminate pain shows a good prognosis for recovery. Therefore, it is likely that exercises done in more than one direction are not as effective, or possibly not effective at all at reducing lower back pain and sciatica. If you have been prescribed exercises that involved this type of multi-directional exercise for back pain, they may not produce the results you are looking for.
How Do I Find My Directional Preference?
In order to determine whether you have a directional preference and what that direction might be, requires an assessment by a Certified Mechanical Diagnosis and Therapy Provider, like Dr. Tracy Norris, DC, Cert. MDT in Wichita Kansas.
Reference: Spine (Phila Pa 1976) 2004 Dec 1;29(23):2593-602. Does it matter which exercise? A randomized control trial of exercise for low back pain. Long A1, Donelson R, Fung T. https://www.ncbi.nlm.nih.gov/pubmed/15564907