Background

Given the widespread recognition that postsurgical movement-evoked pain (MEP) is generally more intense, and more functionally relevant, than pain at rest (PAR), we conducted an update to a previous 2011 review to re-evaluate the assessment of PAR and MEP in more recent postsurgical analgesic clinical trials.

Methods

We searched MEDLINE and Embase for postsurgical pain randomized controlled trials, and meta-analyses, published between 2014 and 2023 in the setting of thoracotomy, knee arthroplasty and hysterectomy using methods consistent with the original 2011 review. Included trials and meta-analyses were characterized according to whether they acknowledged the distinction between PAR and MEP and whether they included PAR and/or MEP as a pain outcome. For trials measuring MEP, pain-evoking maneuvers used to assess MEP were tabulated.

Results

Among the 944 included trials, 504 (53%) did not measure MEP (vs. 61% in 2011) and 428 (45%) did not distinguish between PAR and MEP when defining the pain outcome (vs. 52% in 2011). Among the 439 trials that measured MEP, selection of pain-evoking maneuver was highly variable and, notably, was not even described in 139 (32%) trials (vs. 38% in 2011). Among the 186 included meta-analyses, 94 (51%) did not distinguish between PAR and MEP (vs. 71% in 2011).

Conclusions

This updated review demonstrates a persistent limited proportion of trials including MEP as a pain outcome, a substantial proportion of trials failing to distinguish between PAR and MEP, and a lack of consistency in the use of pain-evoking maneuvers for MEP assessment. Future postsurgical trials need to: a) use common terminology surrounding PAR and MEP; b) assess MEP in virtually every trial if not contraindicated; and c) standardize MEP assessment with common, procedure-specific pain-evoking maneuvers. More widespread knowledge translation and mobilization is required in order to disseminate this message to current and future investigators.