Reliability of Spinopelvic Measurements That May Influence the Cup Position in Total Hip Arthroplasty

Lindsay T Kleeman-Forsthuber; Jacob M Elkins; Todd M Miner; Charlie C Yang; Jason M Jennings; Douglas A Dennis

doi:10.1016/j.arth.2020.06.056

Reliability of Spinopelvic Measurements That May Influence the Cup Position in Total Hip Arthroplasty

J Arthroplasty. 2020 Dec;35(12):3758-3764. doi: 10.1016/j.arth.2020.06.056. Epub 2020 Jun 24.

Authors

Lindsay T Kleeman-Forsthuber¹, Jacob M Elkins², Todd M Miner¹, Charlie C Yang¹, Jason M Jennings¹, Douglas A Dennis³

Affiliations

¹ Colorado Joint Replacement, Denver, CO.
² University of Iowa Hospitals & Clinics, Iowa City, IA.
³ Colorado Joint Replacement, Denver, CO; Department of Biomedical Engineering, University of Tennessee, Knoxville, TN; University of Colorado Health Sciences Center, Denver, CO.

PMID: 32888750
DOI: 10.1016/j.arth.2020.06.056

Abstract

Background: Spinopelvic pathology has been identified as a potential risk factor for instability after total hip arthroplasty. Spinopelvic radiographic parameters used to diagnose spinopelvic disease may also impact optimal cup placement. The purpose of this study was to assess the arthroplasty surgeon accuracy in making spinopelvic measurements.

Methods: Five fellowship-trained or in-training arthroplasty surgeons reviewed 44 lateral lumbar radiographs in two sessions. All evaluators were instructed how to perform measurements but had little experience in doing so. Traditional measurements included the pelvic tilt (PT), pelvic incidence (PI), and sacral slope (SS), and novel measurements included the acetabular ante-inclination (AI) and pelvic femoral angle. Surgeon measurements were compared with those made by experienced engineers. intraclass coefficients (ICCs) were calculated and interpreted.

Results: The interobserver reliability for 4 of 5 of the spinopelvic parameters was good to excellent (ICC >0.75) with the highest reliability seen for PI measurement (ICC = 0.939). Only moderate interobserver reliability was observed for AI measurement (ICC = 0.559). Intraobserver reliability was the highest for the PI and SS, ranging from moderate to good (ICC, 0.718 to 0.896). The lowest intraobserver reliability was seen for the AI (ICC range, 0.026 to 0.545) and pelvic femoral angle (ICC range, 0.035 to 0.828). Surgeon measurements of PT and SS were compared with engineer measurements with extremely poor correlation observed (ICC <0 for all).

Conclusion: Surgeon intraobserver and interobserver reliability in making novel radiographic measurements was low compared with traditional radiographic measurements. Surgeon reliability in making traditional measurements of the PT and SS was very poor compared with experienced assessors using software-based measurements.

Keywords: ante-inclination; pelvic femoral angle; reliability; spinopelvic measurements; total hip arthroplasty.

MeSH terms

Acetabulum
Arthroplasty, Replacement, Hip*
Humans
Radiography
Reproducibility of Results
Sacrum