Reliability and Reproducibility of Sacro-Femoro-Pubic Angle Measurements on Anteroposterior Pelvis Radiographs

Angel M. Reyes, MD; Charles S. Carrier, MD; Adam E. Roy, MD; Pierre-Emmanuel Schwab, MD; Elena Losina, PhD; Antonia F. Chen, MD, MBA; Jeffrey N. Katz, MD, MSc; Jeffrey K. Lange, MD

Arthroplasty Today (Dec 2021)

Reliability and Reproducibility of Sacro-Femoro-Pubic Angle Measurements on Anteroposterior Pelvis Radiographs

Angel M. Reyes, MD,
Charles S. Carrier, MD,
Adam E. Roy, MD,
Pierre-Emmanuel Schwab, MD,
Elena Losina, PhD,
Antonia F. Chen, MD, MBA,
Jeffrey N. Katz, MD, MSc,
Jeffrey K. Lange, MD

Affiliations

Angel M. Reyes, MD: Orthopaedic and Arthritis Center for Outcomes Research, Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Corresponding author. 11 Littell Rd, Brookline, MA 02446, USA. Tel.: + 1 360 487 6858.
Charles S. Carrier, MD: Harvard Combined Orthopaedic Residency Program, Boston, MA, USA
Adam E. Roy, MD: Harvard Combined Orthopaedic Residency Program, Boston, MA, USA
Pierre-Emmanuel Schwab, MD: Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA
Elena Losina, PhD: Orthopaedic and Arthritis Center for Outcomes Research, Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA; Section of Clinical Sciences, Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, Boston, MA, USA; Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
Antonia F. Chen, MD, MBA: Harvard Medical School, Boston, MA, USA; Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA
Jeffrey N. Katz, MD, MSc: Orthopaedic and Arthritis Center for Outcomes Research, Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA; Section of Clinical Sciences, Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, Boston, MA, USA; Departments of Epidemiology and Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
Jeffrey K. Lange, MD: Harvard Medical School, Boston, MA, USA; Department of Orthopaedic Surgery, Brigham and Women’s Hospital, Boston, MA, USA

Journal volume & issue: Vol. 12
pp. 29 – 31

Abstract

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Background: The sacro-femoro-pubic (SFP) angle is a surrogate measurement for pelvic tilt obtained on anteroposterior (AP) pelvis radiographs. It is unknown whether the SFP angle can be measured reliably by senior surgeons and trainees alike. Methods: We conducted an intrareader and interreader reliability study using preoperative AP pelvis radiographs. Using our hospital electronic database, we randomly selected 31 subjects undergoing primary total hip arthroplasty. An attending orthopedic surgeon and two orthopedic surgery residents performed two separate SFP angle measurements for each subject. Intrareader and interreader agreement were measured using intraclass correlation coefficients (ICC). Results: Pairwise intrareader and interreader ICCs ranged from 0.91 to 0.99. Overall ICC was 0.94. Interreader ICCs between the attending surgeon and each orthopedic resident were 0.93 and 0.98, and the ICC between orthopedic residents was 0.91. Interreader mean differences for SFP angle measurements were 2.32 degrees or less: -2.03 (standard deviation: 2.23) and 0.29 (1.64) between the attending surgeon and each orthopedic resident, and 2.32 (2.44) between orthopedic residents. Conclusion: SFP angle may be measured reliably on AP pelvis radiographs by senior clinicians and trainees. SFP angle measurement may prove helpful as an alternative to pelvic tilt measurements when lateral pelvic radiographs are not available.

Published in Arthroplasty Today

ISSN: 2352-3441 (Online)
Publisher: Elsevier
Country of publisher: United States
LCC subjects: Medicine: Surgery: Orthopedic surgery
Website: https://www.journals.elsevier.com/arthroplasty-today/

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