If your lower back aches after walking or your knees feel stiff on stairs, your feet may be where it starts. When a narrow shoe pins the big toe inward, you stop pushing off straight. The foot rolls. The lower leg turns. The knee follows. The hip tilts. The lower back tightens.
Repeat that step thousands of times and it becomes knee pain on stairs, hip pain after a short walk, back pain at night, and errands that need a rest halfway through. This shoe removes the squeeze and keeps your heel and forefoot level, so every joint above your feet has less to fight.