The Role of Dexamethasone in Total Knee Arthroplasty: Effects of Oral and Intravenous Administration on Early Postoperative Pain and Mobilization
Conditions: Knee Osteoarthritis, Gonarthrosis; Primary, Total Knee Arthroplasty
Sponsor: Haseki Training and Research Hospital

STUDY PROTOCOL 
 
COVER PAGE 
Official Title: 
The Role of Dexamethasone in Total Knee Arthroplasty: Effects of Oral and Intravenous 
Administration on Early Postoperative Pain and Mobilization 
Brief Title: 
Oral vs Intravenous Dexamethasone in Total Knee Arthroplasty 
Acronym: 
TKA 
Study Type: 
Observational  
NCT Number: 
Not yet assigned 
Document Type: 
Study Protocol 
Protocol Version: 
Version 1.0 
Document Date: 
01 March 2026 
 
 
 
 
 
 
 
 
 
 

Study Site: Istanbul Haseki Training and Research Hospital – Department of Orthopaedics 
and Traumatology 
Study Design 
This is a single-center, prospective observational cohort study. Participants are assigned to 
cohorts based on the routine perioperative dexamethasone protocol of the surgeon they 
voluntarily choose. No randomization or masking is performed. The time perspective is 
prospective. 
Study Population 
Patients aged 50–80 years undergoing elective primary total knee arthroplasty due to 
advanced knee osteoarthritis will be included. All participants must provide written 
informed consent.  
Inclusion Criteria: 
• 
Age 50–80 years 
• 
ASA I–II 
• 
Primary unilateral TKA 
• 
Ability to provide informed consent  
Exclusion Criteria: 
• 
Revision TKA 
• 
Rheumatoid arthritis 
• 
Chronic corticosteroid use 
• 
Uncontrolled diabetes mellitus 
• 
Uncontrolled hypertension 
• 
Active infection or endocrine disorder 
Study Groups (3 Cohorts) 
• 
Control Group – Routine perioperative care without dexamethasone. 
• 
Intravenous Group – 8 mg IV preoperatively, 4 mg IV postoperative day 1. 
• 
Oral Group – 8 mg oral preoperatively, 4 mg oral postoperative day 1. 
Primary Outcome Measures 
• 
Postoperative pain (VAS (Visual Analog Scale) 0–10,  preoperatively and every 6 
hours for postoperative 48 hours). 

• 
Functional mobility (TUG (Time Up and Go) test, preoperatively and daily during 
postoperative 48 hours). 
• 
Knee Range of Motion – Flexion and Extension degrees (preoperatively and daily 
during the first 2 postoperative days.) 
 
 
 
Secondary Outcome Measures 
• 
Postoperative nausea and vomiting (Numeric Rating Scale (NRS) 0–10, measured 
daily) 
• 
White Blood Cell Count (expressed in ×10³/µL, measured daily) 
• 
C-Reactive Protein Level (expressed in mg/L, measured daily) 
• 
Opioid requirement (Cumulative tramadol dose in mg, first 48 hours). 
• 
Postoperative Glycemic Response (mg/dL, first 48 hours) 
 
 
 
Statistical Analysis Plan 
Normality will be assessed using Shapiro–Wilk testing. Continuous variables will be 
compared using ANOVA or Kruskal–Wallis tests. Repeated measures will be analyzed 
using repeated-measures ANOVA or linear mixed models. Categorical variables will be 
analyzed using Chi-square or Fisher’s exact test. Multivariate regression analysis will 
adjust for confounders. Statistical significance is defined as p < 0.05. 
Ethical Considerations 
The study is conducted in accordance with the Declaration of Helsinki. Ethics Committee 
approval has been obtained. Participation is voluntary and does not alter standard clinical 
management.