Evaluating Spinal Cord Stimulation for Stiff Person Syndrome

Inclusion Criteria: * Is 18 years of age or older at the time that the Informed Consent Form (ICF) is signed. * Has been clinically diagnosed with stiff person syndrome * Has clinical symptoms of muscle rigidity and spasms in the truncal (including abdominal, thoracic paraspinal, and pectoral) or proximal lower limb musculature * Has Cerebrospinal fluid (CSF) Anti-glutamic acid decarboxylase 65 (anti-GAD65) antibodies or serum anti-GAD65 antibodies present at any titer * Is currently trying or has tried in the past at least two conventional therapies with insufficient symptomatic relief or intolerable side effects (such as nonsteroidal anti- inflammatory drugs, topical patches/creams/gels/ointments, physical therapy, acupuncture, bracing, assistive devices, and lifestyle modification). * If taking oral medications, is willing to maintain a stable regimen for the duration of the study period. * Is cleared for an implantable medical device by licensed mental health provider. * Is an appropriate candidate for the surgical procedures required in this study based on clinical judgement of the study physician. * Is willing to and capable of giving written informed consent. * Is willing and able to comply with study-related requirements and procedures and attend scheduled visits. Exclusion criteria: * Is less than 18 years of age at the time at the time that the Informed Consent Form (ICF) is signed. * Has a Body Mass Index (BMI) \> 45. * Has a history of spine surgery or is plann…