Why the Phase of Pain Matters Foot pain while walking is one of the most common reasons people seek physical therapy. Understanding when and where it hurts can reveal the true cause. Its actually diagnostic. (If you want to read more about how we think about diagnostics, read How to Find the Real Cause of Pain: Our 4-Pillar Diagnosis Process). This means we can figure out the pain generator. That is a large list. It can be the fat pad, your fascia (the most common, incorrect diagnosis), plantar intrinsics (muscles on the bottom of the foot which is primarily the flexor digitorum brevis, abductor hallucis, and abductor digiti minimi), the flexor hallucis longus, the tibial nerve, the medial or lateral plantar nerve, the calcaneus, the talus, the bones of the midfoot and forefoot, the foot and ankle joints, ligaments, the hallux (big toe), or the little toes. It does not