Degenerative lumbar spinal stenosis (DLSS) is a common spinal disease in elderly patients. For elderly patients, midline decompression surgery for DLSS is a more suitable approach, as it preserves the disc, lamina, and facet joints while reconstructing the posterior tension bands. In this context, we discuss ligament reconstruction using interspinous artificial ligaments for soft stabilization after microsurgical fenestration to prevent post-decompression segmental instability. Foreign body reaction is a very rare postoperative complication following artificial ligament reconstruction surgery. However, if such a reaction occurs, it can be managed with antihistamines or steroids to control the allergic response. Artificial ligaments are typically made of polyethylene terephthalate, a material with a minimal risk of foreign body reaction; thus, its occurrence is extremely rare. In most cases, removal is unnecessary, as favorable outcomes are observed even in the presence of a foreign body reaction.