The study , observe the effect of releasing the Tourniquet in total knee replacement surgery before closure in comparison with releasing it after wound closure

The effect was assessed by Hb drop post operative and Hematoma formation ( measured by ultrasound ) as well as the wound complication

The study is conducted in tertiary university hospital as a referral hospital for joint arthroplasty , the patients was informed about the study and consent was taken , the same operator , same theater and the same prosthesis company as well as the same radiologist during the study period.

the patient randomly assigned to either group A (Tourniquet release before closure of the wound and hemostasis ensured ) , or a group B ( Tourniquet release after wound closure )

post operative Hb drop was studied between the groups , and each patient underwent ultrasound measurement of the intraarticular hematoma . The wound complication between the groups was also studied .

Inclusion Criteria:

• primary knee osteoarthrosis

Exclusion Criteria:

• Rheumatoid arthritis
• post traumatic arthritis
• revision knee replacement
• patients on anticoagulant/antiplatelet except acetylsalicylic acid 80-100 mg

the study was conducted in University hospital in the Capital city , the patients were from all around the country - Jordan - , as the hospital is as tertiary hospital most of the patients were above 60 , mostly female

the measurement of hemoglobin drop and intra articular hematoma measurement by ultrasound