Association between phase angle and functional disability among patients with lumbar spinal stenosis: The SPSS-OK study

Article type: Research Article

Authors: Wada, Osamu^a | Yamada, Minoru^b | Kamitani, Tsukasa^c | Mizuno, Kiyonori^a | Tadokoro, Kou^d | Kurita, Noriaki^{e; f; g; *}

Affiliations: [a] Anshin Hospital, Chuo-ku, Kobe City, Hyogo, Japan | [b] Graduate School of Comprehensive Human Sciences, University of Tsukuba, Bunkyo-ku, Tokyo, Japan | [c] Department of Healthcare Epidemiology, School of Public Healh, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, Japan | [d] Anshin Clinic, Chuo-ku, Kobe City, Hyogo, Japan | [e] Department of Clinical Epidemiology, Graduate School of Medicine, Fukushima Medical University, Fukushima City, Fukushima, Japan | [f] Department of Innovative Research and Education for Clinicians and Trainees (DiRECT), Fukushima Medical University Hospital, Fukushima City, Fukushima, Japan | [g] Center for Innovative Research for Communities and Clinical Excellence (CiRC2LE), Fukushima Medical University, Fukushima City, Fukushima, Japan

Correspondence: [*] Corresponding author: Noriaki Kurita, Department of Clinical Epidemiology, Graduate School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima City, Fukushima 960-1295, Japan. E-mail: [email protected].

Abstract: BACKGROUND: Whether the lower phase angle associated with worse physical function is a result of pain and muscle weakness in patients with lumbar spinal stenosis (LSS) is unclear. OBJECTIVE: To evaluate the association between phase angle and back pain-specific disabilities in patients with LSS. METHODS: In this single-center, cross-sectional study, 491 participants with LSS were enrolled. The phase angle and back pain-specific disability were measured using bioelectrical impedance analysis and the Oswestry Disability Index, respectively. General linear models were used to examine associations between phase angle and the Oswestry Disability Index with or without adjustment for age, sex, low back and lower limb pain, numbness in the lower extremities, total fat mass, and lower limb muscle mass. RESULTS: The mean (SD) phase angle was 4.4∘ (1.0∘), and the mean Oswestry Disability Index was 36.1 (14.1) points. Greater phase angles were associated with less Oswestry Disability Index points (p= 0.037) independent of fat mass, low back pain, and hip or lower limb pain. CONCLUSIONS: A lower phase angle was associated with worse functional disability. Low phase angle may be an indicator of functional impairment due to low back pain associated with LSS.

Keywords: Phase angle, bioelectrical impedance analysis, functional disability, lumbar spinal stenosis, Oswestry Disability Index

DOI: 10.3233/BMR-220038

Journal: Journal of Back and Musculoskeletal Rehabilitation, vol. 36, no. 2, pp. 399-405, 2023