Functional recovery after bilateral globus pallidus internus deep brain stimulation in primary dystonia: A prospective clinical evaluation

Background: Primary dystonia is a disabling movement disorder often refractory to medical therapies. While bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) is established for motor symptom control, broader functional outcomes are less well characterized. To evaluate motor and real-world functional improvements following bilateral GPi DBS in patients with primary dystonia. Methods: A prospective observational study was conducted on 20 patients (mean age 34.7 years) with medically refractory primary dystonia. All underwent stereotactically guided bilateral GPi DBS. Functional outcomes assessed included skeletal deformity, facial twitching severity, wheelchair dependence, self-feeding ability, and bladder control. Evaluations were conducted at baseline and 6 months postoperatively. McNemar’s test and the Wilcoxon signed-rank test were used for statistical analysis. Results: Significant improvements were observed across all domains. Skeletal deformity rates decreased from 95% preoperatively to 10% postoperatively ( P < 0.001). Facial twitching improved significantly ( P = 0.005). Wheelchair dependence dropped from 50% to 5% ( P = 0.007). Self-feeding ability increased from 30% to 95% ( P < 0.001), and bladder control improved from 10% to 95% ( P < 0.001). No serious adverse events related to surgery or stimulation were reported. Conclusion: Bilateral GPi DBS in primary dystonia significantly improves motor symptoms and critical functional domains such as mobility, independence in self-care, and bladder control. These findings support the broader benefits of DBS, emphasizing its role in enhancing quality of life. Further studies with larger samples and longer follow-up are needed to confirm these outcomes.