Open midline decompression with ligament reconstruction is a benefical surgical approach for treating lumbar spinal stenosis and instability. This technique helps preserve the facet joints and maintain spinal stability, but postoperative hematoma remains one of its most important complications. Postoperative epidural hematoma can cause serious neurological problems if not recognized early. Most hematomas are asymptomatic, but in some cases, they compress the dural sac or nerve roots, leading to neurological deficits that may require urgent evacuation. Considering some risk factors, preventive measures focus on thorough preoperative evaluation, proper management of anticoagulant medication, and meticulous bleeding control during surgery. The use of advanced hemostatic agents such as gelatin–thrombin sealants and careful placement of drainage tubes are also key steps. Overall, careful surgical technique and close postoperative monitoring are essential to reduce the risk of hematoma and improve patient outcomes.