The purpose of the study is to evaluate the validity of PROMS after reconstructive surgery or amputation in the leg region. In this context, the German version of the LIMB-Q, a questionnaire-based "Patient-reported outcome measurement" (PROM), will be validated for the German-speaking region and any necessary cultural adaptations will be made for the future use of the questionnaire.

In addition, the aim is to establish a context between the LIMB-Q as a PROM and clinical outcome measurements (Maryland Foot Score, American Orthopedic Foot and Ankle Society Score).

Complex tissue loss in the lower extremities is often a clinical challenge. Many different factors must be considered and weighted in the treatment algorithm, with functional restoration of the leg remaining the primary goal. Surgeon assessment alone is not sufficient to fully describe treatment outcomes. Different outcome measurement tools have been used in the past in an attempt to eval-uate these complex issues. Surgical outcomes that focus on complications and function from the physician's perspective provide valuable information but do not give a complete picture. Therefore, as in other areas of healthcare, patient-reported outcomes have become an integral part of as-sessing the quality and effectiveness of the services provided. Only a combination of clinicians' and patients' perspectives can contribute to obtaining a conclusive picture of the services provided. However, no validated patient reported outcome measure (PROM) instrument exists to date. Lower extremity injuries are life-changing events for patients. While approximately 70% undergo recon-struction, there are currently 200,0000 individuals in the United States living with a lower extremity amputation secondary to trauma. There is currently no PRO instrument in use for patients with limb-threatening lower extremity injuries. Instead, commonly used PRO instruments include the Musculoskeletal Tumor Society and the "Toronto Extremity Salvage Score", both designed for use in musculoskeletal oncology, as well as the Western Ontario and McMaster University Osteoar-thritis Index, designed for arthritis patients". These measures are limited, as they were not de-signed using qualitative interview data of patients with limb-threatening lower extremity traumatic injuries. They therefore, have not proven to be reflective of the important COI relevant to this pa-tient population. PRO instruments focusing on patients who have undergone amputation only are also in use, such as the Trinity Amputation and Prosthesis Experience Scales. However, there is no PRO instrument that is designed for all patients with limb-threatening lower extremity traumatic injuries that measures COI relevant to both reconstruction and amputation patient groups.

PRO instruments designed specifically for a given disease process are important, as they measure concepts such as satisfaction with appearance, body image, function, mobility, and psychosocial wellbeing, providing meaningful, precise, and reliable feedback on important patient- centered out-comes relevant to a specific patient population. This will allow meaningful, precise and reliable feedback on important patient-centered outcomes, with the potential for widespread use in clinical audit for quality improvement, and local, national and international research efforts.

In clinical research the LIMB-Q will have the capability to measure differences in outcomes im-portant to patients, allowing it to compare different treatments for severe lower extremity trauma. While substantial research has focused on identifying the "superior" treatment method between re-construction and amputation, this PRO instrument will be the first research instrument to allow this question to be asked while taking into account COI important to patients. In clinical care the it will provide patients with a structured and reliable method of communicating outcomes to providers, allowing for real-time adjustments in care to improve overall results.

The preliminary LIMB-Q scales have been developed using international standards for PRO in-strument development. Briefly, semi-structured qualitative interviews, combined with expert opin-ion and a literature review were used to generate a conceptual framework and preliminary set of scales. Next, cognitive debriefing interviews and solicitation of expert opinion were performed to further refine the preliminary instrument for clarity and comprehensiveness of content. The prelimi-nary LIMB-Q scales is now undergoing a large-scale, multi-institutional field test..

A comparison of outcomes assessment shows that surgeons tend to overestimate outcomes com-pared with patients. CROMs are well accepted by patients and have a high reliability. It is argued that PROM results are more difficult to interpret than objective CROMs due to higher inter- and intra-observer variability and subjective PROM assessment for cultural and other individual rea-sons. Thus, it is important to establish a context between already established CROMs and PROMs.

The purpose of the study is to evaluate the validity of PROMS after reconstructive surgery or am-putation of the legs due to trauma. The aim of the study is to validate the German version of the LIMB-Q, a questionnaire-based patient-reported outcome measurement (PROM) for the German-speaking region and to make any necessary cultural adaptations for the future use of the question-naire in order to be able to utilize the LIMB-Q in the future for all affected patients who receive re-constructive surgery or amputation of the lower extremity in the context of trauma in order to gain a better understanding of factors that have an influence on patient satisfaction. Furthermore, a con-text between the LIMB-Q as PROM and clinical outcome measures (CROMs) will be established.

Inclusion Criteria:

• Male and female patients after lower extremity reconstructive surgery aged 18 years or older
• Male and female patients aged 18 years or older who have received /suffered a lower extremity amputation in the past.
• Written informed consent from the participating individual.

Exclusion Criteria:

• Patients with a tumor disease affecting the lower extremity.

Patients after reconstructive surgery and/or amputation of the lower extremity of the Department of Plastic Surgery and Hand Surgery, University Hospital Zurich, Switzerland

After encryption and statistical analysis of the data, they are shared anonymously with Duke University, Durham, NC, USA using Qualtrics (www.qualtrics.com) for joint publication. At no time do the involved persons on the Duke University side have access to the original unencrypted data of the patients from the Clinic for Plastic Surgery and Hand Surgery of the University Hospital Zurich. The data will be shared to obtain a larger international study cohort for psychometric analysis and validation of the LIMB-Q.

After statistical analysis

Patient data will be shared after enryption and statistical analysis