PURPOSE Obesity poses challenges to preoperative mobility and functional recovery for arthroplasty patients, yet postoperative weight loss remains elusive. This study aims to investigate postoperative weight changes and their impact on functional scores following knee and hip arthroplasty, exploring factors influencing these changes.

METHODS A total of 459 knee and hip arthroplasty cases with a 2-year follow-up were analyzed. BMI and Oxford scores were tracked, alongside factors including comorbidities, corticosteroid use, physiotherapy, and unilateral vs. bilateral surgery.

EXPECTED OUTCOMES Based on the study's design and the data available, we anticipate observing the impact of changes in patients' BMI on clinical scores as an independent variable. Additionally, we aim to elucidate the effects of comorbidities, corticosteroid use, physiatrist follow-up, and the type of surgical procedure on both BMI and clinical outcomes. Through this analysis, we expect to gain a comprehensive understanding of how these factors interplay to influence postoperative recovery and overall patient health.

Inclusion Criteria:

• Patients who underwent primary TKA and THA with a 2-year follow-up were included

Exclusion Criteria:

• Patients who underwent bariatric surgery before or after the surgery
• Incomplete 2-year follow-up
• Whom BMI or Oxford scores could not be accessed

Yes All demographic data, clinical scores, and BMI measurement results will be shared.