Degenerative disc disease (DDD) causes the vacuum phenomenon, resulting in the accumulation of air in the disc space. Pneumorrachis refers to the presence of air in the spinal canal, which is sometimes associated with DDD. Air may form pseudocysts and compress the root or thecal sac, causing symptoms similar to those of disc herniation or an osteophyte. Pneumorrachis, which is a rare condition, needs proper preoperative magnetic resonance imaging and computed tomography for an accurate diagnosis and differentiation from other pathologies, such as a discal or facetal cyst. The pathogenesis of pneumorrhachis remains unclear, and treatment guidelines have not been established. Asymptomatic cases need observation. Symptomatic cases may require percutaneous aspiration, which can result in incomplete pain relief and high recurrence rates. Open or microsurgical decompression and excision provide relief, but very few reports have described the role of full-endoscopic management for this condition. Herein, we report the case of a 78-year-old woman with an epidural gas-containing pseudocyst and left-sided S1 radiculopathy, who was managed with endoscopic decompression and excision of the cyst. The case highlights the need for thorough imaging and the establishment of standard guidelines for diagnosing and managing such cases. Endoscopic techniques offer better visualisation and manipulation, leading to significant improvement in symptoms. Advances in endoscopic techniques have made it easier to perform lumbar surgery through the endoscope, making it a viable option.