Morphological features in the lumbar multifidus in athletes with chronic non-specific low back pain (CNSLBP): A systematic review & meta-analysis

Authors: Wai Keung WONG1, Allan C.L. FU2, Sharon M.H. TSANG1,

1 Department of Rehabilitation Sciences, Faculty of Health and Social Science, The Hong Kong Polytechnic University, Hong Kong, China

2 Faculty of Medicine and Health, The University of Sydney, Australia

Presenting author: Wai Keung Wong

Email address: [email protected]

Title: Morphological features in the lumbar multifidus in athletes with chronic non-specific low back pain (CNSLBP): A systematic review & meta-analysis

Introduction

Thirty-two to 89% of athletes suffered from CNSLBP resulting in causing the loss of playing times for up to one year. Lumbar multifidus is the key main stabiliser. The diminished size and increased side-to-side asymmetry of lumbar multifidus have been reported as contributing factors to fatigue in individuals with CNSLBP. In the general population, imaging studies demonstrated the association between the morphological features of the lumbar multifidus. Athletes are suspected to have a higher risk due to high-intensity training and frequency matches but the compositions of lumbar multifidus between athletes with and without CNSLBP, remain unknown.

Aims:

To examine the cross-sectional area (CSA), muscle thickness (MT) and echo intensity (EI) of the lumbar multifidus, and to identify parameter(s) that offers valid assessment in athletes with CNSLBP.

Methods:

This systematic review and meta-analysis (PROSPERO registration: CRD42023404357) was conducted in PubMed/MEDLINE, CINAHL, Embase and Web of Science. Studies included were those with outcome measures correlated with the morphological features of lumbar multifidus in the athletes with and without CNSLBP. Newcastle Ottawa Scale (NOS) was used to assess the quality of the included studies. All relevant data of the included studies were pooled and analysed.

Results and Discussion:

Nineteen studies were included in the analysis. CSA (p=0.022; ES=-1.312), MT in contraction status (p=0.010; ES= -0.770) and EI (p<0.001; ES=-2.296) were shown statistically significant differences between athletes with and without CNSLBP. The conflict between the results of EI in meta-analysis and the included studies may be due to an unprecise estimation of the fatty infiltration in EI measurement of lumbar multifidus and high heterogenicity. Further studies may be required to establish the relationship between EI and CNLBP. Small sample size and lacking correlation reported between the morphology of lumbar multifidus and pain intensity were the limitations in the study.

Conclusion:

Three morphological features, including CSA and MT in contraction status showed negative relationship and EI, showed a positive relationship in the athletes with CNSchronic non-specific LBP. Studying of discriminative validity of EI measurement is recommended for its potential application in objectively quantifying the relative compositions within muscle in athletes with chronic non-specific LBP, for comparative and longitudinal studies.