Centralpoststrokepain:somatosensoryabnormalitiesandthepresenceofassociatedmyofascialpainsyndrome

Central poststroke pain (CPSP) is a challenging neuropathic pain condition that develops after stroke, affecting areas where patients have somatosensory deficits. While CPSP is well-recognized, patients after stroke can also develop other types of pain, including myofascial pain syndrome (MPS) - a musculoskeletal condition characterized by trigger points and referred pain patterns. Despite being part of the broader post-stroke pain spectrum, no one had systematically studied how often MPS occurs alongside CPSP. This matters because MPS could complicate diagnosis (since both conditions can cause pain in areas with neurological deficits) and treatment planning.

Researchers evaluated 40 patients with confirmed CPSP using standardized clinical examinations and brain imaging. All patients had documented strokes affecting somatosensory pathways and met strict criteria for neuropathic pain. The team performed comprehensive sensory testing (temperature, vibration, touch, pain sensitivity) and systematically examined patients for MPS by palpating specific muscle groups for trigger points. They used validated pain scales (Visual Analog Scale, McGill Pain Questionnaire) and depression measures, and classified stroke locations based on brain scans.

The examination protocol was standardized to ensure consistent evaluation across all patients.

The results revealed that MPS was surprisingly common, affecting 67.5% (27 of 40) of CPSP patients. Most patients (90%) had ischemic strokes, and pain typically began within three months of the stroke in 75% of cases. All patients showed thermo-sensory abnormalities (problems sensing hot and cold), which is a hallmark of central pain. MPS was most frequent in patients with supratentorial extra-thalamic lesions (92.9%) and thalamic-capsular lesions (100%), compared to pure thalamic (50%) or brainstem (37.5%) lesions.

The most commonly affected muscles were the trapezius (50% of patients), followed by various neck and back muscles. Importantly, patients with and without MPS showed no significant differences in pain intensity, depression scores, or other pain characteristics.

This study challenges the idea that CPSP should be diagnosed only when other pain conditions are ruled out, since most CPSP patients actually have mixed pain syndromes. The high prevalence of MPS suggests that 'pure' central neuropathic pain is actually the exception rather than the rule. For clinicians, this means they should routinely assess stroke patients for both conditions, as treating only the neuropathic component while ignoring trigger points could leave patients with ongoing pain. For patients, this research suggests that comprehensive pain management addressing both central and myofascial components may be more effective than focusing on neuropathic pain alone.

The findings also highlight the need for multidisciplinary care teams that can address both neurological and musculoskeletal aspects of post-stroke pain.