The Correlation Between Pelvic Motion and Lumbar Motion in Patients Presenting With a Lumbar Spinal Pathology: Implications for Assessing Dislocation Risk in Total Hip Arthroplasty

Emily S. Mills, MD; Jennifer C. Wang, BS; Joshua Sanchez, BA; Andy Ton, BS; Ram K. Alluri, MD; Nathanael D. Heckmann, MD; Raymond J. Hah, MD

Arthroplasty Today (Apr 2023)

The Correlation Between Pelvic Motion and Lumbar Motion in Patients Presenting With a Lumbar Spinal Pathology: Implications for Assessing Dislocation Risk in Total Hip Arthroplasty

Emily S. Mills, MD,
Jennifer C. Wang, BS,
Joshua Sanchez, BA,
Andy Ton, BS,
Ram K. Alluri, MD,
Nathanael D. Heckmann, MD,
Raymond J. Hah, MD

Affiliations

Emily S. Mills, MD: Corresponding author. Department of Orthopaedic Surgery, Keck Medical Center of USC, 1200 N. State St., GH 3900, Los Angeles, CA 90333, USA. Tel.: + 1 303 905 1123.; Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA
Jennifer C. Wang, BS: Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA
Joshua Sanchez, BA: Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA
Andy Ton, BS: Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA
Ram K. Alluri, MD: Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA
Nathanael D. Heckmann, MD: Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA
Raymond J. Hah, MD: Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA

Journal volume & issue: Vol. 20
p. 101105

Abstract

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Background: Arthroplasty surgeons use the change in sacral slope (ΔSS) from sitting to standing as a measure of spinal motion. The relationship between ΔSS and the change in lumbar lordosis (ΔLL), an established spinal motion measure, has not been well studied. This study aims to determine the correlation between ΔSS and ΔLL. Methods: Consecutive patients presenting to a spine clinic from 2020 to 2021 at a single institution were retrospectively studied. Standing and sitting lateral radiographs were measured for SS and LL. Patients were divided using ΔSS and ΔLL into stiff (0°-9°), normal (10°-30°), or hypermobile (>30°) category. Patients with a ΔSS-determined normal or hypermobile spine but a ΔLL-determined stiff spine were compared to the rest of the cohort. Results: Overall, 100 patients were included. Of these patients, 47% had the same classification when looking at ΔSS and ΔLL, whereas 53% had conflicting classifications. Twenty percent of patients had a ΔSS-determined normal or hypermobile spine but ΔLL-determined stiff spine. The correlation between ΔSS and ΔLL was 0.510 (P < .001). When isolating patients who underwent lumbar fusion, the correlation between ΔSS and ΔLL was 0.345 (P < .001). Conclusions: ΔSS has a moderate correlation with ΔLL in patients presenting for evaluation of their lumbar spine but low correlation in patients with lumbar fusion. In our cohort, 20% of patients had a ΔSS-determined normal or hypermobile spine but a ΔLL-determined stiff spine, representing a potential high-risk dislocation cohort not captured by ΔSS alone. Arthroplasty surgeons should revisit classifying spinal motion based solely on ΔSS.

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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Abstract

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