What causes pain in the back of the left foot sole?

Pain in the back of the left foot may be caused by overexertion, inappropriate footwear, plantar fasciitis, Achilles tendinitis, or heel spurs. It can be improved through rest, changing shoes, medication, and physical therapy. If pain persists or is accompanied by swelling or limited mobility, prompt medical attention is recommended.

1. Overexertion: Prolonged standing, walking, or intense physical activity can place continuous strain on the muscles and fascia at the rear of the left foot sole, leading to fatigue-related pain. Symptoms may temporarily improve with rest but often worsen upon resuming activity. It is advised to reduce weight-bearing activities, elevate the affected limb when possible, and soak the feet in warm water to promote local blood circulation and relieve muscle fatigue.

2. Inappropriate Footwear: Wearing shoes with overly thin, soft soles or poor fit over time fails to provide adequate support for the foot arch, resulting in uneven pressure and repeated friction or compression at the back of the left foot sole, causing pain and possibly a sensation of soreness or heaviness. It is recommended to switch to comfortable shoes with sufficient sole thickness and structural support, and to avoid high heels or pointed-toe shoes to reduce foot stress.

3. Plantar Fasciitis: Repeated microtrauma to the plantar fascia leads to aseptic inflammation, which causes pain at the back of the left foot sole. Pain is typically most noticeable upon waking or after prolonged inactivity, and may slightly improve with movement. Under medical guidance, patients may use medications such as diclofenac diethylamine gel, celecoxib capsules, or eperisone hydrochloride tablets to alleviate symptoms.

4. Achilles Tendinitis: Inflammation occurs due to repetitive strain and injury to the Achilles tendon, affecting the posterior aspect of the left foot sole and causing localized pain. Pain intensifies during walking or jumping, and there is significant tenderness upon pressing the tendon insertion site. Under medical supervision, medications such as ibuprofen sustained-release capsules, naproxen sodium tablets, or flurbiprofen gel patches may be used to relieve discomfort.

5. Heel Spurs: Localized bone overgrowth (osteophyte) on the calcaneus forms a bony spur that irritates surrounding soft tissues, causing pain at the back of the left foot sole. During walking, friction between the spur and soft tissue increases with activity, worsening the pain. Medications such as etoricoxib tablets, enteric-coated diclofenac sodium tablets, or Huoxue Zhitong plasters may be used under medical advice to manage symptoms.

Daily care includes limiting daily walking distance and avoiding prolonged standing; choosing breathable shoes with proper arch support; soaking feet in warm water before bedtime, and gently massaging the soles to relax muscles.