The goal of this clinical trial is to determine whether performing total knee replacement surgery (total knee arthroplasty, TKA) without a tourniquet is clinically equivalent to performing the procedure with a tourniquet in adults with symptomatic knee osteoarthritis.

A tourniquet is commonly used during surgery to reduce bleeding and improve the surgeon's view. However, some studies suggest it may be associated with certain complications. It is currently unclear whether using a tourniquet meaningfully changes outcomes compared to not using one. This study aims to assess whether both approaches result in similar outcomes within a clinically acceptable range.

The main question this study aims to answer is:

Is total blood loss during surgery equivalent between TKA performed with a tourniquet and TKA performed without a tourniquet, within a predefined margin of ±100 mL?

Additional questions include:

Are surgical field quality, postoperative pain, functional recovery, and complication rates comparable between the two techniques?

Researchers will compare:

TKA performed with a pneumatic tourniquet TKA performed without a tourniquet

to determine whether outcomes between the two approaches are equivalent rather than whether one is superior to the other.

Participants will:

Be randomly assigned to one of the two surgical groups using a computer-generated process Undergo standard total knee replacement surgery and routine perioperative care Have blood loss assessed during and after surgery Be monitored for pain, recovery of function, wound healing, and complications during hospital stay and follow-up visits

This study is designed as a randomized controlled equivalence trial to determine whether both surgical approaches produce comparable outcomes within clinically acceptable limits, in a standardized local setting.

Inclusion Criteria:

• • Age ≥ 18 years.

  • Clinical and radiographic diagnosis of knee osteoarthritis requiring primary unilateral Total Knee Arthroplasty.
  • Medically fit for elective surgery (typically ASA I-III).
  • Able to provide informed consent.

Exclusion Criteria:

• • Revision TKA or bilateral simultaneous TKA.

  • Preexisting coagulopathy or active anticoagulation that cannot be perioperatively managed per protocol.
  • Known allergy or contraindication to tranexamic acid.
  • Active infection or immunosuppression.
  • Severe peripheral vascular disease in the operative limb.
  • BMI > 45 kg/m²
  • Inability to provide informed consent or comply with follow-up