Pain is categorized into acute, subacute, and chronic stages based on how long it lasts and how the body responds. Understanding the differences helps guide treatment and recovery.

Acute Pain (0-6 weeks) – This is immediate pain following an injury, surgery, or medical condition. It serves as a warning signal and usually improves as the body heals.

Example: A person sprains their ankle while running. The pain is sharp and intense at first, accompanied by swelling. With rest, ice, and treatment, the pain gradually decreases as the injury heals.

Subacute Pain (6-12 weeks) – This is the transition phase between acute and chronic pain. The initial injury has started to heal, but pain may persist due to lingering inflammation, muscle weakness, or improper healing.

Example: A person undergoes back surgery and still experiences discomfort eight weeks later. While the surgical site is healing, stiffness and mild pain remain, requiring rehabilitation and physical therapy.

Chronic Pain (Beyond 12 weeks) – Pain that persists beyond the expected healing time is considered chronic. It may no longer be directly tied to an injury and can be influenced by nerve dysfunction, inflammation, or central sensitization.

Example: A person develops knee pain after a minor injury. Months later, even after the original injury has healed, the pain remains, making it difficult to walk or stand for long periods. The pain may stem from nerve changes rather than ongoing tissue damage.

Because the causes and mechanisms of pain change over time, treatment approaches also differ. Acute pain is managed with rest, ice, and short-term medications, while chronic pain requires a comprehensive approach, including physical therapy, interventional procedures, and neuromodulation therapies like spinal cord stimulation (SCS) or peripheral nerve stimulation (PNS). Understanding these stages helps patients and doctors choose the most effective treatments for long-term relief.