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The following is a summary of “Pain catastrophizing and trunk co-contraction during lifting in people with and without chronic low back pain: A cross sectional study,” published in the August 2024 issue of Pain by Ippersiel et al.

Trunk co-contraction during lifting was considered a guarded motor response to tasks perceived as threatening, which is believed to stabilize the trunk and protect the body in the face of potentially risky or challenging movements. 

Researchers conducted a retrospective study to estimate the impact of pain catastrophizing effects on trunk co-contraction during lifting, comparing individuals with low back pain to those without pain. 

They performed 10 repetitions of a lifting task in adults with high pain catastrophizing (back pain: n = 29, healthy: n = 7) and low pain catastrophizing (back pain: n = 20, healthy: n = 11). Data on the rectus abdominis, erector spinae, and external oblique muscles were collected using electromyography. Co-contraction indices were calculated for the rectus abdominis/erector spinae and external oblique/erector spinae pairings. Pain catastrophizing was measured using the Pain Catastrophizing Scale, and task-specific fear was measured using the Photograph Series of Daily Activities Scale. Three-way mixed ANOVAs were used to analyze the effects of back pain vs. healthy group, pain catastrophizing (high vs. low), lifting phase (lifting vs. replacing) groups, and their interactions.

The results showed no significant effects of pain catastrophizing, lifting phase, or interactions (P> 0.05). Group effects revealed that individuals with back pain revealed greater co-contraction in the bilateral erector spinae/rectus abdominis pairings compared to healthy participants, regardless of pain catastrophizing and lifting phase (P< 0.05). Additionally, Spearman correlations indicated that greater task-specific fear was associated with increased erector spinae-left external oblique co-contraction, but only in individuals with back pain (P< 0.05).

They concluded that greater co-contraction in the back pain group occurred independently of pain catastrophizing, as measured with a general questionnaire. 

Source: onlinelibrary.wiley.com/doi/full/10.1002/ejp.4717