We tend to think that the legs alone control walking. In fact, walking is the result of thousands of small spinal movements as well, especially in the low back. It makes sense, then, that patients whose low backs are impaired might have a harder time walking.
Patients often develop styles of movement to compensate for back problems. Research has shown that patients with chronic low back pain tend to take relatively shorter strides. These patients may walk more cautiously than the average person to prevent or reduce pain.
Patients with low back pain also show more variability in movement. For patients with low back pain, one stride may be different from the next. Spinal movement itself actually fluctuates quite a bit in these patients. Researchers think that low back pain reduces patients' control over movement, possibly by interfering with the body's information systems. This no doubt makes it hard for patients to maintain a consistent, effective gait.