True neurogenic thoracic outlet syndrome (nTOS) is a rare condition resulting from brachial plexus compression, frequently associated with congenital anomalies such as cervical ribs or fibrous bands. We report a unique case of nTOS involving both a cervical rib and fibrous band, complicated by an incidental intraoperative finding of a fascicular rupture in the lower part of lower trunk. Notably, the patient had no history of trauma but had undergone multiple sessions of manual therapy and a single extracorporeal shockwave therapy to the cervical region, raising concerns about a potential iatrogenic contribution.