title: Impact of oxidative stress on early postoperative knee function and muscle injury biochemical markers: Is it possible to create an ischemic preconditioning effect in sequential ischemic surgical procedures?
abstract: OBJECTIVE
  Simultaneous bilateral total knee arthroplasty (TKA) with prolonged tourniquet time has the potential to trigger ischemia-reperfusion injury, which can adversely affect knee function. Studies suggest that the magnitude of injury is less if it occurs following an ischemic event which takes place in another part of the body, known as ischemic preconditioning (IPC). The purpose of this study was to investigate the impact of oxidative stress on muscle injury and knee function and to elucidate if potential IPC effect can attenuate ischemia-reperfusion injury metabolites and prevent poor functional outcomes in single-stage bilateral TKA.
  
  
  METHODS
  Thirty patients who underwent single-stage bilateral TKA under tourniquet were enrolled in the study. All procedures were initiated from the right limb. Upon completion of the procedure, the left tourniquet was inflated 20 minutes after the first tourniquet was deflated. The tourniquet time was noted. Pre- and postoperative levels of malondialdehyde (MDH), creatine kinase (CK), and lactate dehydrogenase (LDH) were evaluated. Knee function was assessed postoperatively at 1 month using WOMAC score.
  
  
  RESULTS
  Postoperative levels of MDH, CK, and LDH were significantly increased in both extremities compared to preoperative levels. Serum MDH, CK, and LDH levels were not found to be correlated with tourniquet time for either extremity. Compared to the left extremity, the right extremity revealed increased postoperative oxidative stress, which was indicated by elevated serum MDH, CK, and LDH levels. Although tourniquet time and postoperative serum MDH, CK, and LDH levels were not found to be correlated with WOMAC index in either knee, the average change in WOMAC score at 1 month postoperatively was found to be higher in the left knee compared to the right.
  
  
  CONCLUSIONS
  The biochemical and functional outcomes can be attributed to potential IPC effect. During bilateral TKA, a 20-minute interval between tourniquets can create IPC effect and attenuate the magnitude of ischemia-reperfusion injury, preserving better functional outcomes.
authors: Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Orthopedics and Traumatology, Ankara, Turkey. drerdem2007@gmail.com.
authors: Erdem
authors: E
authors: Aktaş
authors: Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Biochemistry, Ankara, Turkey.
authors: Çiğdem
authors: Ç
authors: Atay
authors: Çukurova University Faculty of Medicine, Department of Orthopedics and Traumatology, Adana, Turkey.
authors: Mehmet Ali
authors: MA
authors: Deveci
authors: Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Orthopedics and Traumatology, Ankara, Turkey.
authors: Murat
authors: M
authors: Arıkan
authors: Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Orthopedics and Traumatology, Ankara, Turkey.
authors: Güray
authors: G
authors: Toğral
authors: Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Orthopedics and Traumatology, Ankara, Turkey.
authors: Ahmet
authors: A
authors: Yıldırım
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D015415:Biomarkers / Q000097:blood; D006801:Humans; D019194:Ischemic Preconditioning / Q000379:methods*; D007719:Knee Joint / Q000098:blood supply*; D008315:Malondialdehyde / Q000097:blood*; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D011183:Postoperative Complications / Q000503:physiopathology*; D015427:Reperfusion Injury / Q000503:physiopathology*; D014111:Tourniquets
chemical_list: D015415:Biomarkers; D008315:Malondialdehyde