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The Reconstructive Pelvic Anatomy classification system

Bone & Joint Open, vol. 7, pp. 871–881

Abstract

Aims: Pelvic reconstruction in the setting of significant bone loss has become increasingly complex, with advancements such as custom 3D-printed prostheses now used in both large oncological resections and revision total hip arthroplasty (rTHA) with massive bone loss. Surgeons must consider how to best reconstruct the pelvis to optimize patient outcomes. The Reconstructive Pelvic Anatomy (RPA) classification system is proposed to aid in communication, reconstructive planning, and developing research cohorts suitable for modern pelvic reconstructions. This study aimed to 1) describe the development of the RPA classification as a novel classification system for pelvic reconstruction; 2) demonstrate the content and construct validity of the system; and 3) investigate its interobserver and intraobserver agreement. Methods: A group of orthopaedic surgeons and researchers, based in Sydney, Australia, developed the system's four domains, which together form the overall classification. A total of 23 pelvic reconstruction surgeons provided an assessment of each domain's clarity and relevance, producing an Item-Content Validity Index (I-CVI). They then applied the classification to the surgical plan and postoperative radiograph of 20 pelvic reconstructions twice, at a minimum of two weeks apart. Construct validity was assessed by agreement between observers and authors. Interobserver and intraobserver agreement was assessed using the kappa statistic. Results: A total of 23 surgeons completed the assessment of content validity, and 18 surgeons completed both surveys. Each domain demonstrated content validity for both relevance and clarity (I-CVI > 0.78). Authors and observers had moderate agreement on the classification supporting construct validity (k = 0.6) with a median agreement of 90% for individual domains. Interobserver agreement was moderate overall (k = 0.54), with individual domains having substantial or better agreement (k = 0.73 to 0.82) except for anterior fixation (k = 0.57). Intraobserver agreement of individual domains was substantial or almost perfect (k = 0.76 to 0.84) with moderate agreement for the overall classification (k = 0.6). Conclusion: This study establishes the content and construct validity of the RPA classification system as a novel classification system for pelvic reconstruction, and its reliability to support its use as a communicative tool, and in research and surgical planning.

Authors 15

  1. Royal Prince Alfred Hospital

    Affiliation as printed

    Department of Orthopaedic Surgery, Royal Prince Alfred Hospital, Sydney, Australia

  2. Royal Prince Alfred Hospital · UNSW Sydney

    Affiliation as printed

    Department of Orthopaedic Surgery, Royal Prince Alfred Hospital, Sydney, Australia

    School of Clinical Medicine, UNSW Medicine & Health, Sydney, Australia

  3. Royal Prince Alfred Hospital

    Affiliation as printed

    Department of Orthopaedic Surgery, Royal Prince Alfred Hospital, Sydney, Australia

  4. Royal Prince Alfred Hospital

    Affiliation as printed

    Department of Orthopaedic Surgery, Royal Prince Alfred Hospital, Sydney, Australia

  5. Royal Prince Alfred Hospital

    Affiliation as printed

    Department of Orthopaedic Surgery, Royal Prince Alfred Hospital, Sydney, Australia

  6. The University of Sydney · Institute for Musculoskeletal Health

    Affiliation as printed

    Institute for Musculoskeletal Health, Faculty of Medicine and Health, University of Sydney, Sydney, Australia

  7. Royal Prince Alfred Hospital

    Affiliation as printed

    Surgical Outcomes Research Centre (SOuRCe), Royal Prince Alfred Hospital, Sydney, Australia

  8. The University of Sydney · Royal Prince Alfred Hospital

    Affiliation as printed

    Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, Australia

    Surgical Outcomes Research Centre (SOuRCe), Royal Prince Alfred Hospital, Sydney, Australia

  9. Royal Prince Alfred Hospital · Chris O’Brien Lifehouse · Sydney Local Health District

    Affiliation as printed

    Integrated Prosthetics and Reconstruction, Chris O’Brien Lifehouse, Sydney, Australia

    Royal Prince Alfred Institute of Academic Surgery, Sydney Local Health District, Sydney, Australia

  10. Princess Alexandra Hospital

    Affiliation as printed

    Department of Orthopaedics, Princess Alexandra Hospital, Brisbane, Australia

  11. Flinders University

    Affiliation as printed

    Flinders University, College of Medicine & Public Health, Adelaide, Australia

    South Australian Bone & Soft Tissue Tumour Unit, Adelaide, Australia

  12. The University of Western Australia · Sir Charles Gairdner Hospital

    Affiliation as printed

    Department of Orthopaedics, Sir Charles Gairdner Hospital, Perth, Australia

    Faculty of Medicine, The University of Western Australia, Perth, Australia

    Perth Orthopaedic & Sports Medicine Centre, Perth, Australia

  13. Leiden University Medical Center

    Affiliation as printed

    Department of Orthopaedic Surgery, Leiden University Medical Center, Leiden, The Netherlands

  14. Royal Prince Alfred Hospital · UNSW Sydney · Wagga Wagga Base Hospital

    Affiliation as printed

    Department of Orthopaedic Surgery, Royal Prince Alfred Hospital, Sydney, Australia

    University of New South Wales Rural Clinical School, Wagga Wagga, Australia

  15. Royal Prince Alfred Hospital

    Affiliation as printed

    Department of Orthopaedic Surgery, Royal Prince Alfred Hospital, Sydney, Australia

    School of Medicine, University of Notre Dame, Sydney, Australia

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References 55