The goal of this observational study is to verify the association of previously underexplored psychological variables on postoperative pain experience and its progression over time in patients undergoing emergency and elective orthopedic surgeries, including both sexes (age range: 18-65). The main questions it aims to answer are:

1. Do psychological factors such as dysfunctional personality traits and emotional regulation explain the experience of pain after surgery and after six months?
2. Does the experience of the body mediate the relationship between dysfunctional personality traits and the experience of pain after surgery and after six months?
3. Does the experience of pain differ between patients who underwent emergency and elective orthopedic surgery (after surgery and after six months)?

Researchers will compare the pain experience of patients undergoing emergency orthopedic surgery to those undergoing elective orthopedic surgery to see if there are significant differences in pain outcomes and recovery trajectories.

Participants will:

• complete psychological questionnairs to evaluate dysfunctional personality traits, emotional regulation, and body image;
• report their subjective pain level and provide information on their coping strategies for managing pain and information about pain interference in everyday functioning;
• engage in follow-up evaluation (6 months after the surgery) to assess the impact of pain on their daily activities and rehabilitation progress and complete some of the questionnaires again.

The primary goal of the project is to formulate empirically grounded theses on the association of psychological variables and the type of pain experienced preoperatively on shaping the pain experience among orthopedic patients. Psychological variables, selected based on the literature, include dysfunctional personality traits, emotional regulation, and body image, while the pain experience is understood as the subjective level of pain experienced, pain coping strategies, and pain interference in daily functioning. Additionally, the project aims to compare the pain experience of patients undergoing emergency versus elective orthopedic surgeries in a longitudinal perspective, allowing for consideration of the dynamic nature of pain and its development over time. Orthopedic surgeries are considered among the most painful as they involve significant intervention in both the skeletal system and surrounding soft tissues. Postoperative discomfort often extends beyond acute pain, with 19-22% of orthopedic patients developing chronic pain after surgery. Many orthopedic patients experience reduced mobility and require rehabilitation-their pain experience and associated challenges may be unique. Furthermore, orthopedic surgery is invasive and deeply impacts body boundaries. Therefore, the study also seeks to examine the role of body image (as a mediating variable) in shaping the pain experience.

The research questions addressed will provide recommendations for pain management that highlight the importance of a biopsychosocial perspective, as well as recommendations for developing preventive and therapeutic programs for psychological work with orthopedic patients based on the study's findings.

Plan of the project Phase 1 - Data Collection: This will take place at the Department of Orthopedic and Traumatic Surgery of Żeromski Hospital in Krakow. Physicians will identify eligible patients based on inclusion and exclusion criteria, after which the researcher will seek patient consent for participation. A total of 170 patients aged 18-65 years who underwent elective or emergency orthopedic surgery will participate, completing questionnaires within 72 hours post-surgery. The following tools will be used: The Personality Inventory for ICD-11 (PiCD), Difficulties in Emotion Regulation Scale (DERS), The Pain Coping Strategies Questionnaire (CSQ), Visual analogue scale (VAS), Multidimensional Body Self Relations Questionnaire (MBSRQ), and Pain Interference Scale. Relevant medical information will be collected to control for confounding variables. This phase aims to generate empirical data on selected psychological variables and postoperative pain characteristics.

Phase 2 - Follow-up: This will occur six months postoperatively via online questionnaires, where patients will complete some of the previous questionnaires again. This phase aims to collect empirical data to (1) analyze changes in the pain experience over time and (2) analyze changes in body image and pain coping strategies over time post-surgery.

Data Analysis: Analysis of empirical data in SPSS will include mediation analysis, stepwise regression analysis, and analysis of group mean differences. This will support the following research objectives: (1) identification of psychological variables explaining postoperative pain experience and its changes over time; (2) comparative analysis of pain experiences among emergency versus elective surgery patients; (3) identification of the role of body image as a mediator between psychological variables and pain experience.

Interpretation of Results: Formulating conclusions from the analyses to achieve the main research objective: to empirically establish theses on (a) the impact of psychological variables; and (b) the impact of the type of pain experienced preoperatively on shaping the pain experience among orthopedic patients.

Dissemination of Results: Preparing study results in the form of articles, conference presentations, and popularization efforts to achieve the following research objectives: (1) providing recommendations for pain management that emphasize the need to consider a biopsychosocial perspective, particularly for orthopedic patients; (2) providing recommendations for developing preventive and therapeutic programs for psychological work with orthopedic patients based on the study's findings.

Inclusion Criteria:

• age: participants aged 18 years or older;
• surgical procedures: individuals scheduled to undergo either emergency or elective orthopedic surgeries, including but not limited to joint replacements (e.g., hip or knee arthroplasty) and fracture repairs;
• time after operation: undergoing orthopedic surgery up to 72 hours before the psychological examination;
• informed consent: ability to provide informed consent and willingness to participate in the study;
• language proficiency: proficiency in the language of the questionnaires used in the study (Polish).

Exclusion Criteria:

• psychiatric disorders: diagnosed psychiatric disorders (e.g., severe depression, anxiety disorders) that are not managed or stable.

This study focuses on patients who have undergone either emergency or elective orthopedic surgeries, specifically those involving significant interventions on the musculoskeletal system, such as joint replacements or fracture repairs. The source of study participants is Stefan Żeromski Specialist Hospital in Krakow, Department of Orthopedic and Trauma Surgery.

The cohort consists of adult participants (aged 18 years and older) who have been informed about the study and provided their consent to participate. This population will include both males and females. Interventions of interest: psychological questionnaires, pain assessment, longitudinal follow-up.

• data dictionary (a description of the variables)
• demographic data
• outcome measures