Chronic limb sensory abnormalities caused by retained intraspinal metallic foreign body: a case report.

Intraspinal foreign body retention is a rare clinical entity, usually resulting from trauma, surgery, or invasive procedures, and may lead to progressive neurological dysfunction. We report a patient who presented with burning pain in the right sole and bilateral lower limb weakness, and was diagnosed with a retained metallic foreign body in the thoracic spinal canal by imaging examinations. We discuss the clinical features, imaging diagnosis, and surgical management based on the diagnostic and therapeutic process of this case. This report indicates that invasive therapies such as acupuncture carry the potential risk of needle breakage, migration, and subsequent intraspinal foreign body retention, which deserves clinical attention. Strict standard operation during acupuncture is crucial to avoid such iatrogenic complications.