Thalamic Pain Syndrome
Thalamic pain syndrome (also called Dejerine-Roussy syndrome or central post-stroke pain) is a severe, chronic neuropathic pain condition affecting 2-8% of stroke patients, characterized by burning or aching pain with allodynia in the body region corresponding to a lesion in the spinothalamic tract, most classically from thalamic stroke but possible from any lesion along the spinothalamic-thalamocortical pathway. 1, 2
Clinical Presentation
Pain characteristics:
- Burning or aching quality, typically severe and treatment-resistant 1, 3
- Allodynia (pain from normally non-painful stimuli like touch, cold, or movement) 1
- Hyperpathia (exaggerated pain response) 1
- Affects the face, arms, and/or legs in a distribution corresponding to the CNS lesion 1, 2
Timing and impact:
- Onset typically within days to weeks after stroke, with most patients symptomatic within the first month 1
- Can be chronic or lifelong, dramatically hindering activities of daily living, sleep, and quality of life 1, 2, 3
Anatomical Basis
Lesion locations:
- Classically associated with thalamic stroke, particularly involving the anterior pulvinar nucleus (a major spinothalamic target) 1, 4
- Can result from lesions anywhere along the spinothalamic and thalamocortical tracts within the CNS 1
- Lesions involving the anterior pulvinar nucleus combined with spinothalamic dysfunction have 93% sensitivity and 87% positive predictive value for developing thalamic pain 4
Diagnostic Criteria
Required elements for diagnosis:
- Pain occurs after stroke 1
- Pain located in body area corresponding to the CNS lesion 1
- Pain not accounted for by nociceptive or peripheral neuropathic causes 1
Common diagnostic pitfall: CPSP is often underdiagnosed or misdiagnosed as musculoskeletal or visceral pain—always exclude other serious causes before attributing all post-stroke pain to CPSP 2, 5
Treatment Algorithm
First-Line Pharmacotherapy
Amitriptyline 75 mg at bedtime is the most strongly recommended initial therapy, demonstrating proven efficacy in lowering daily pain ratings and improving global functioning 1, 6, 2
Alternative first-line option:
- Lamotrigine reduces daily pain ratings and cold-induced pain, though only 44% of patients achieve good clinical response 1, 6, 5
Second-Line Pharmacotherapy
When first-line agents fail or are not tolerated:
- Gabapentin or pregabalin should be tried next 1, 6, 2, 5
- SNRIs, particularly duloxetine, are also reasonable second-line options 1, 2, 5
Important caveat: Be cautious with anticholinergic side effects of amitriptyline, particularly in elderly patients 5
Treatment-Resistant Cases
Reserve for refractory pain only:
- Opioids or tramadol should be used only for treatment-resistant cases due to significant risk of physical dependency 1, 6, 2, 5
Interventional Options
Motor cortex stimulation is reasonable for intractable pain unresponsive to pharmacotherapy, achieving >50% pain reduction on visual analog scale in 50-83% of patients, with effectiveness lasting up to 2 years 1, 6, 2, 5
Deep brain stimulation targeting specific thalamic nuclei (such as nucleus ventrocaudalis parvocellularis internis) may provide relief for severe hemi-body pain, though evidence is limited to case reports 7, 8
Avoid TENS: Transcutaneous electrical nerve stimulation is not effective for central post-stroke pain and should not be used 1, 5
Essential Non-Pharmacological Components
All pharmacotherapy must be combined with:
- Therapeutic exercise 1, 6, 2, 5
- Psychosocial support 1, 6, 2, 5
- Individualized patient-centered approach implemented by an interdisciplinary team with expertise in mental health and central pain management 1, 2, 5
Monitoring Treatment Response
Assess response using standardized serial measurements:
Emerging Therapies
Hyperbaric oxygen therapy has been reported in a single case report to resolve symptoms and markedly improve quality of life in thalamic pain syndrome, though this requires further investigation before routine recommendation 3