Correlations Analysis of Different Pelvic Tilt Definitions: A Preliminary Study. Issue 2 (May 2023)

• Record Type: Journal Article
• Authors: Chai, Yuan; Boudali, A. Mounir; Walter, William L.
• Is Part Of: HSS journal. Volume 19:Issue 2(2023)
• Page Start: 187
• Page End: 192
• Publication Date: 2023-05
• Subjects: pelvic tilt -- pelvic orientation -- correlation analysis -- hip surgery -- spinal surgery; Musculoskeletal system -- Surgery -- Periodicals; Orthopedic surgery -- Periodicals; Musculoskeletal System -- surgery -- Periodicals; Orthopedic Procedures -- Periodicals; Orthopédie -- Périodiques; Appareil locomoteur -- Maladies -- Périodiques; Appareil locomoteur -- Maladies -- Patients -- Réadaptation -- Périodiques; 617.47005
• DOI: 10.1177/15563316221136128
• Languages: English
• ISSNs: 1556-3316

Abstract

Background: Pelvic tilt (PT) is described as the pelvic orientation along the transverse axis, yet 4 PT definitions were established based on radiographic landmarks: anterior pelvic plane (PTa ), the center of femoral heads to sacral plate (PTm ), pelvic outlet (PTh ), and sacral slope (SS). These landmarks quantify a similar concept, yet understanding of their relationships is lacking, and their differences are sometimes ignored. Purpose : This study aimed to examine the correlations and differences of PT definitions for education and research purposes. Methods : This study reviewed 105 sagittal pelvic radiographs of patients (68 men and 37 women) awaiting hip surgery at a single clinic. Hip hardware and spine pathologies were examined for subgroup analysis. Two observers annotated 4 PTs in a gender-dependent manner and repeated it after 6 months. The linear regression model and intraclass correlation coefficient (ICC) were applied with a 95% confidence interval. Results : The SS showed no correlation to the other 3 PT definitions, except for females in the hip hardware subgroup (n = 17). PTm demonstrated very strong linear correlation to PTh ( r > 0.9) under the linear model PTm = 0.951 × PTh – 68.284. Conclusion : The PTm and PTh can be calculated from each other under a simple linear regression equation, which enables comparisons between them. SS presented poor correlations to the other PT parameters, except for the female subgroup with hip implant that required further analysis; PTa -related comparisons showed high anatomical variations between patients.