Are pain-related psychological variables associated with postural control in low back pain?

Abstract

BACKGROUND: One of the biological contributors to low back pain (LBP) is an altered postural control, particularly during challenging postural tasks. Moreover, in individuals with LBP, higher levels of pain-related fear and pain catastrophizing are (weakly) associated with reduced spinal movement, increased trunk muscle activity and worse maximal physical performance. It remains unknown whether pain-related psychological variables are associated with postural control, as measured by center of pressure (CoP) variables, in individuals with LBP.

METHODS: A systematic review and meta-analysis was conducted. The protocol was registered on PROSPERO (CRD42021241739). Pubmed, Web of Science and PsycInfo were searched until November 2022. Studies were eligible for inclusion if they evaluated postural control during bipedal upright standing by measuring CoP parameters and reported at least one pain-related psychological variable. Correlation coefficients between pain-related psychological variables and CoP parameters were extracted from the studies or obtained through author contact in case they were not originally reported. Random-effect models were used to calculate pooled correlation coefficients between pain-related psychological variables and CoP parameters during different postural tasks with increasing difficulty. Subanalyses were performed regarding either positional, dynamic or frequency CoP parameters.

RESULTS: Sixteen studies (n= 723 participants) were included. Pain-related fear (16 studies) and pain catastrophizing (three studies) were the only reported pain-related psychological variables. Results indicated that both pain-related fear (-0.04 < pooled r < 0.15) and pain catastrophizing (0.28 < pooled < 0.29) were weakly associated with CoP parameters during different postural difficulties (e.g. vision occluded). For all associations, the certainty of evidence was rated very low.

CONCLUSIONS: Overall, there is very low certainty of evidence for weak, overall positive, associations between pain-related psychological variables and postural control during bipedal standing in individuals with LBP, regardless of the difficulty of the postural task.