Chronic post-surgical pain: causes and treatments

Name: Chronic post-surgical pain: when pain doesn't go away after surgery
Creator: Dr. Mauricio Casarsa
Published: 2026-05-18

What chronic post-surgical pain is

Chronic post-surgical pain is defined as pain that persists for more than three months after surgery, related to the operated area, without evident surgical complications to explain it and without any other identifiable cause.

It is not "imagined" pain. It is a recognized, well-studied complication with clear neurobiological underpinnings. The vast majority of patients who develop it had poorly controlled acute postoperative pain or nerve injury during surgery — the two main factors in its genesis.

The typical features:

Pain that begins with the surgery and never fully resolves.
It frequently has a neuropathic component: burning, electric shocks, tingling, allodynia (the scar hurts when brushed).
It can worsen with cold, weather changes, fatigue or stress.
Left untreated, it tends to have a significant impact on quality of life.

A technical nuance: a large share of chronic post-surgical pain has a neuropathic component, caused by nerve injury or irritation during the operation. That is why it responds poorly to standard painkillers and better to medications specifically designed for neuropathic pain, combined with image-guided procedures when there is a clear target: blocks of the affected peripheral nerves, scar injections, pulsed radiofrequency in selected cases. Identifying this component completely changes the strategy and avoids cycling through regimens that are never going to work.

Why it happens

The main mechanisms are:

Nerve injury during surgery: even in well-performed procedures, small nerves can be cut or compressed, generating chronic neuropathic pain.
Central sensitization: when acute postoperative pain is severe and poorly controlled, the central nervous system "learns" that pain pattern and perpetuates it.
Abnormal scarring: keloid or retractile scars, or scars containing neuromas, can cause persistent local pain.
Chronic inflammation: in some cases, sustained low-grade inflammation in the operated area contributes to the pain.
Genetic and psychosocial factors: individual susceptibility and factors such as preoperative anxiety or misaligned expectations also play a role.

Surgeries with the highest risk

The incidence of chronic post-surgical pain varies widely by procedure:

Thoracotomy (open chest surgery): 30 to 50% of patients develop chronic pain, frequently with an intercostal neuropathic component.
Mastectomy: 20 to 50% have some degree of chronic pain, often with a neuropathic component from injury to the intercostobrachial nerve.
Inguinal hernia repair: 10-30%, with neuropathic pain from injury to the ilioinguinal, iliohypogastric or genitofemoral nerves.
Knee surgery (joint replacement, ligament repair): 15-20% may have significant persistent pain despite a mechanically successful procedure.
Spine surgery: so-called "post-laminectomy syndrome" or "failed back surgery syndrome" affects a significant percentage of patients operated on for lumbar disc herniation or stenosis.
Cardiac surgery: chronic sternal pain or pain at the saphenous vein graft site.
Amputations: phantom limb pain or stump pain.

How it is treated

Treatment depends on the predominant type of pain (neuropathic, nociceptive, mixed), its location and its functional impact. The approach is usually multimodal:

Targeted pharmacological treatment for neuropathic pain: gabapentinoids, dual-action antidepressants, low-dose tricyclic antidepressants, topical lidocaine patches for localized areas.
Selective blocks of the affected nerve: intercostal block for post-thoracotomy pain, ilioinguinal/iliohypogastric nerve blocks for pain after hernia repair, paravertebral block, erector spinae plane block.
Pulsed radiofrequency: a neuromodulation technique useful in post-surgical neuropathic pain when blocks confirm the source but the relief is short-lived.
Injection of scar neuromas: when there is a localized painful point in the scar that reproduces the pain.
Targeted physical therapy: scar release, joint mobility work, postural re-education.
Addressing the emotional component: anxiety, frustration at not regaining the quality of life you expected. Cognitive behavioral therapy adds value when there is a significant psychosocial component.
Neuromodulation: in cases refractory to conventional treatment, spinal cord stimulators or dorsal root ganglion blocks are an option.

My approach is twofold. On one hand, intervening as early as possible when a patient has had persistent post-surgical pain for more than two or three months, because the longer it becomes chronic, the harder it is to reverse. On the other, working on prevention when a patient is headed for surgery with a high risk of chronification: proper perioperative pain management, anesthetic techniques that reduce the risk, and attentive follow-up afterwards. Pain medicine does not begin once the condition is already established; whenever possible, it anticipates it.

Can it be prevented

Yes, to a large extent. Preventing chronic post-surgical pain is one of the current priorities of perioperative medicine. The strategies with the best evidence:

Effective control of acute postoperative pain: poorly controlled pain in the first days promotes sensitization and increases the risk of chronification.
Preventive multimodal analgesia: a combination of paracetamol (acetaminophen), NSAIDs (when indicated), perioperative gabapentinoids in high-risk surgery, and regional techniques (nerve blocks, epidural analgesia).
Regional anesthetic techniques: when the procedure allows it, regional techniques (image-guided blocks, epidural or intrathecal anesthesia) significantly reduce the incidence of chronic post-surgical pain.
Identifying at-risk patients: high preoperative anxiety, pre-existing chronic pain, female sex and younger age are risk factors. In these patients, a more careful perioperative strategy changes outcomes.
Early consultation with Pain Medicine: if pain persists with unusual features 1-3 months after surgery, seeking care early improves the prognosis. Waiting "to see if it goes away on its own" until the condition is 6 months old makes later treatment more difficult.

When a patient with chronic post-surgical pain comes back and tells me they can wear certain clothes again, sleep on a certain side or return to activities they had given up, I know the plan worked. Success is not always the complete disappearance of pain, but it does mean a meaningful improvement in function and quality of life. The most important thing with these conditions is not to give up: behind an 'it's normal after surgery' there is often a treatable entity that just needs to be identified and addressed with the right tools, integrated into a coherent plan.

Is the pain from your surgery not going away?

Chronic post-surgical pain has specific treatments. Seeking care early significantly improves your chances of recovery.

💬 I still have pain after surgery

Post-surgical pain — frequently asked questions

When is post-surgical pain considered chronic?

When it persists for more than three months after surgery and is not explained by an active surgical complication. From that point on, the pain mechanisms differ from those of acute postoperative pain and require a specific approach.

Does it mean the surgery was done badly?

Not necessarily. Chronic post-surgical pain is a recognized complication that can occur even after technically flawless surgery, due to injury to small nerves, individual predisposition or perioperative factors. It is not the surgeon's "mistake" but an expected complication in a percentage of patients.

Does it make sense to reoperate if the pain persists?

Almost never. Reoperating for chronic post-surgical pain without a clear structural cause usually makes things worse by adding tissue injury and potentially affecting new nerves. The exception is when a specific, treatable scar neuroma is identified. Before any reoperation, an evaluation by a Pain Medicine specialist is always worthwhile.

How much improvement is possible?

It depends on the type of pain, how long it has been present and the response to treatment. With a well-executed multimodal approach, most patients achieve a significant reduction in pain and a better quality of life, although the pain does not always disappear completely.

References and further reading

Schug SA, Lavand'homme P, et al. The IASP classification of chronic pain for ICD-11: chronic postsurgical or posttraumatic pain. Pain. 2019;160(1):45-52.
Kehlet H, Jensen TS, Woolf CJ. Persistent postsurgical pain: risk factors and prevention. Lancet. 2006;367(9522):1618-1625.
Macrae WA. Chronic post-surgical pain: 10 years on. Br J Anaesth. 2008;101(1):77-86.
Werner MU, Kongsgaard UE. Defining persistent post-surgical pain: is an update required? Br J Anaesth. 2014;113(1):1-4.

Dr. Mauricio Casarsa

Anesthesiologist, specialist in Pain Medicine and Interventional Pain Management. Postgraduate training at UBA (Fundación Dolor) and UNLP (CAIDBA). Staff physician at Hospital Alemán de Buenos Aires.

MN 137756 · San Isidro · Villa Urquiza