Difference in Return to Sports Activity After Hip Arthroplasty by THR or Resurfacing

The literature is very scarce on Total Hip Arthroplasty(THA) in young patients. To date, there is no comparison on activity resumption based on prosthesis type on a national scale. Total Hip Arthrosplaty (THA) has been subject to a French registry since 2015 for patients operated by resurfacing , but no analysis of prosthesis wear has been conducted. A retrospective study with a follow-up exceeding 10 years is required to address this point and is the subject of another ongoing research. Resurfacing allows the preservation of anatomical elements but remains limited in France. The primary cause of THA revision identified is periprosthetic fracture. After resurfacing, a THA is performed, while after THA, only revision THA is possible but entails a longer operative time with a significant financial impact.

The aim of the research is to compare the level of physical activity at 1 year follow-up, according to the type of prostheses in adult patients under 50. It is part of presenting the practices of THA in young individuals in France during a symposium organized by the SFHG for 2025.

Research Hypothesis Regardless of the type of implants used, total hip arthroplasty yields excellent results in young patients with early resumption of activities, including sports. A meta-analysis of 11 studies comprising 2297 patients shows that 70%-90% of patients resumed sports activities within 6-12 months post-THA . A more recent systematic literature review confirms that 82% of patients have resumed sports activity on average at 6 months .

The research hypothesis is that there is no difference in physical activity at 1 year between patients operated with different types of prostheses, including dual mobility.

Justification of Methodological Choices Given the number of young patients undergoing THA per year in France , and considering a 5% margin of error and a 95% confidence interval, the sample size to be included is 500 patients.

A retrospective monocentric study is proposed given the scarcity of data in this young population. It will include adult patients under 50 operated on from 2015 to 2020. Participants will be divided into three groups according to the type of prosthesis: hip resurfacing, ;soft-hard THA, and hard-hard THA.

A comprehensive review of the medical records will be conducted to collect data.

Physical activity will be assessed at 1 year post-surgery using the International Physical Activity Questionnaire (IPAQ), a reliable and validated tool . The primary outcome is the level of physical activity at 1 year, and secondary outcomes include functional scores (HHS, WOMAC), complications, and prosthesis survival rate.

Ethical Considerations This study complies with the ethical principles outlined in the Declaration of Helsinki. Participant data will be anonymized to ensure confidentiality. Informed consent will be obtained from all participants.

Expected Results It is expected that there will be no significant difference in physical activity level at 1 year between patients operated with different types of prostheses. The results will provide valuable information on the optimal type of prosthesis for young patients undergoing THA and contribute to improving patient outcomes and satisfaction.

Primary objective The primary objective of the research is to compare the level of physical activity of participants at 1 year between those operated by resurfacing and those operated for a THA, taking into account their usual level.

Secondary objectives

The secondary objectives of the study are to:

1\. Compare physical and professional activity:

* Compare the level of physical activity of patients at 1 year between the 4 studied prosthesis groups, taking into account their usual level. * Compare the level of physical activity at 1 year to the preoperative level between the 2 groups and then between the 4 prosthesis groups. * Compare the change in physical activity level between the 2 groups and then between the 4 prosthesis groups in relation to usual level and preoperative level * Compare the time to return to physical and sporting activity in the year following hip arthroplasty. * Compare the time to return to usual professional activity. * Evaluate the quality of return to activity. * Evaluate early complications after total hip arthroplasty.

* Compare the participants postoperative experience. * Analyze the factors influencing the return to physical activity. * Describe the type of implant, surgical approach and clinical parameters in each group Evaluation criteria Main evaluation criterion The main evaluation criterion is the 1-year difference in the UCLA score measuring participants physical activity in relation to their usual level for the resurfacing group and for all THAs.

Secondary evaluation criteria

The secondary evaluation criteria corresponding to the secondary objectives are:

1. For each prosthesis group:

* The 1-year difference in the UCLA score measuring the participants physical activity in relation to their usual level * The 1-year difference in the UCLA score measuring physical activity in relation to the preoperative level * The UCLA score at different times (usual level, preoperative, 6 weeks, 3 months, 6 months, 12 months). * The time to return to activities and sports * The time to return to usual professional activity * The quality of return to activity is evaluated by the Oxford hip functional scores. * Complications and the rate of revision surgery (if applicable) .Participants experience is measured by the SHV (Subjective Hip Value) Score and the Forgotten Hip Score (/100, 100=normal) at all study visits compared to the preoperative value.

* The factors influencing the time to return to physical activity at the usual level in the year following prosthetic surgery taken into account for the analysis are patient-related parameters (rehabilitation or not, age, physical activity, medical history including inflammatory diseases), surgery-related parameters (type of implant, surgical approach and length of hospitalization) * The type of implant, surgical approach and clinical outcomes Research design Research scheme Observational, non-inferiority, non-randomized, prospective, multicenter, national study.

Patients operated on the hip will be classified into 4 groups according to the type of prosthesis: * The resurfacing group * The THA group (hard-soft) * The THA group (dual mobility) * The THA group (hard-hard) Methods to limit bias Choice of centers Inclusion control Research Procedure The research procedure consists of collecting data from the medical records of patients followed in the context of current practice (demographics, anthropometry, comorbidities, medical history, etiology, surgery-related data, first mobilization, length of stay, discharge, type and duration of rehabilitation). In addition to current practice, patients will be asked to complete questionnaires on their return to activity (daily, professional and sports) with a systematic collection of postoperative events and any complications. No medical procedures or visits have been added in the context of this research.

Questionnaires Assessing Physical Activity The patients; level of activity is assessed by the Devane score: it assesses work-related and/or sports activities. It is a score that gives an overall assessment of the participants level of activity or sedentary lifestyle rather than their actual sports practice. The score ranges from 1 to 5 depending on the participants answers, with 5 corresponding to the most intense activities .

The participants pre-operative sports profile is assessed by 3 questions asked to the participant.

Post-operative return to sports activity is assessed by 1 question (yes/no with 4 modalities to explain the reason for no). If the participant has resumed sports activity, 4 additional questions are asked about the frequency per week, whether it is the same activity, whether it is at the same level as before the intervention and the type of activity.

The participant level of physical activity is assessed by the UCLA score, from the University of California, Los Angeles . This scale was originally developed by surgeons to assess the physical activity levels of patients who had undergone hip and knee arthroplasty . It is a 10-level, single-item scale, ranging from 10, for a patient who regularly participates in impact sports, to 1, for a patient who is completely inactive, dependent on others and unable to leave their home.

Questionnaires Assessing Hip Function

The functional results of the hip are assessed by the participant with the following questionnaires:

. The Oxford Hip Score; (OHS-12 Delaunay et al, 2009) questionnaire is composed of 12 questions. It measures pain (on 6 items) and hip function (on 6 items) in relation to activities of daily living such as walking, the ability to dress, and sleep disturbances. Each question has 5 possible answers. Each corresponds to a value of 0 (= highest severity) to 4 (= total or almost total absence of symptoms). The sum of the answers to the questions is normalized on a scale between 0 and 100.

The SHV (Subjective Hip Value) questionnaire is an analog evaluation scale coded from 0 to 100 (= Normal hip)

The FJS (Forgotten Joint Score) HIP or Forgotten Hip Score is set at 100, with 100 corresponding to a normal hip .

Other Questions Asked of the Patient Patients will be asked questions about bleeding, swelling, and wound healing in the days and weeks after surgery. Immediate complications and reoperation, if applicable, will be collected.

In addition, patients will be asked about the duration of work stoppage and sports cessation before and after surgery.

Treatments and Associated Procedures Authorized Associated Treatments/Procedures Any treatment necessary for the routine care of the participant is authorized.

Prohibited Associated Treatments/Procedures No associated treatment or procedure is prohibited during the study.

Conduct of the Research Research Schedule Duration of the inclusion period: 6 months Duration of participation for each participant: maximum 15 months Total duration of the research: 21 months

Visit 1

Visit 1 is the inclusion visit, corresponding to the pre-operative visit with the surgeon. It is conducted by the investigator physician and usually takes place between 3 and 1 month before the surgical procedure (D0). This visit includes:

Providing the information sheet and explaining the research Verifying all eligibility criteria Obtaining the participants non-opposition by the physician Collecting demographic and anthropometric data (age, sex, height, weight) Collecting comorbidities and history of the hip and spine, etiology Visit 2

Visit 2 corresponds to the sending of questionnaires by email to the participant 14 days before the surgical procedure D0 (Visit 3):

• Subjective Hip Value (SHV) Score [Срок оценки: Days 14 and 3,6, 12 mounths]
• The Forgotten Joint Score (FJS) [Срок оценки: Day 0, and 3 ,6,12 mounths]
• Oxford Hip Score (OHS) [Срок оценки: Day 0, and 3 ,6,12 mounths]
• The DEVANE Score [Срок оценки: Day 0, 12 mounths]
• Age [Срок оценки: Day 0]
• Gendre [Срок оценки: Day 0]
• Implant type [Срок оценки: Day 0]
• Surgical approach [Срок оценки: Day 0]
• Rehabilitation [Срок оценки: 12 mounths]
• medical and surgical history [Срок оценки: Day 0]