central post-stroke pain
/ CPSP /
Most pain has an obvious cause out in the body — a cut, a sprain, a burn — and a nerve faithfully reports it. Central post-stroke pain is the unsettling opposite: there is nothing wrong with the painful body part at all, yet it burns, aches, or stings constantly. The fault lies inside the brain itself, in the very circuits that are supposed to process sensation. The alarm is sounding with no fire, and it can be relentless.
This pain comes from the stroke damaging the brain's sensory pathways — classically a small stroke in the thalamus, the relay station for body sensation, though other locations can do it. Weeks to months after the stroke, the affected side begins to hurt in odd ways. The pain is usually described as burning, freezing, aching, or pins-and-needles, and it is often paired with strange sensations: a light touch or even a cool breeze can feel painful (allodynia), or the limb may feel oddly numb and painful at the same time. Because the painful area looks and tests normal, the pain is sometimes wrongly dismissed as imagined.
In rehabilitation central post-stroke pain matters because it is genuinely hard to treat and can dominate a person's life, wreck sleep, and sap the energy needed for therapy. It generally does not respond to ordinary painkillers (the kind used for a sore joint); instead it is approached with medicines aimed at calming overactive nerve signalling, alongside the wider toolkit of a pain program — pacing, mood support, and education. The honest caveat is that complete relief is uncommon; the realistic goal is to turn the pain down enough to live and to keep rehabilitating, not to switch it off entirely.
A few weeks after a small thalamic stroke, a woman's left arm and leg begin to burn constantly, and the brush of a bedsheet on that side feels sharply painful even though the skin is unharmed. Standard painkillers do little; her team starts a nerve-calming medicine and pacing strategies, aiming to make the pain bearable rather than to abolish it.
The painful limb is physically normal; the fault is in the brain's sensory circuits.
Central post-stroke pain is real, not imagined, even though the limb tests normal — and it usually does not respond to ordinary painkillers, which leads to it being missed or dismissed. It is distinct from the mechanical pain of a subluxed shoulder, which has a physical cause.