Inclusion Criteria:  Age ≧ 20 year-old the patient has been confirmed ACL rupture and the reconstruction is indicated sign IRB and operation consent  Exclusion Criteria:  combined other ligament or extremities injury prior the same knee surgery open wound or operation history at knee joint Severe knee osteoarthritis history of multiple joint arthritis or rheumatoid arthritis Systemic diseases (infections, malignancies, immunodepression) patients with bleeding tendency, anticoagulant or antiaggregant therapies patients with Hb values < 11 g/dl and/or platelet values < 150,000/mm refuse to sign Informed Consent Form and operation consent