Diferenciación clínica de la espasticidad y la distonía espástica tras ictus crónico con electromiografía de superficie: una serie de casos

Introduction: Spasticity affects a large number of stroke patients, limiting their mobility and autonomy. Surface electromyography (sEMG) is the most suitable option for quantifying spasticity and differentiating it from other phenomena. Despite evidence of dry needling's effect on spasticity, it has not been quantified using sEMG, nor have other patterns of muscle overactivity been explored. Case presentation: Four cases of patients with chronic stroke and spasticity are presented, who received intensive therapy for 4 weeks, combined with a weekly session of ultrasound-guided dry needling in the medial gastrocnemius muscle. Muscle activity was evaluated using sEMG at rest and during stretching, the Modified Ashworth Scale (MAS), and walking tests at the start of the study (T0), after the first dry needling session (T1), and at the end of the treatment (T2). Different phenotypes were identified based on electromyographic activity: high activity during stretching, high variability, high activity at rest and during stretching, and a combination of the above. Results: Electromyographic activity during stretching was reduced in cases with high response and variability to stretching without spastic dystonia, while resting activity was reduced in those cases that did present spastic dystonia. The MAS scale improved in all patients, and walking tests exceeded clinically significant thresholds. No adverse effects were reported. Conclusion: A theoretical-practical framework is proposed for assessing muscle tone with sEMG, describing different clinical phenotypes in patients with chronic stroke and supporting the combination of dry needling and intensive therapy to improve both spasticity and gait.