Concordance of qualitative bone scintigraphy results with presence of clinical complex regional pain syndrome 1: meta-analysis of test accuracy studies

Background: To date, no attempt has been made to investigate the agreement between qualitative bone scintigraphy (BS) and the presence of complex regional pain syndrome 1 (CRPS 1) and the agreement between a negative BS in the absence of CRPS 1.

Aims: To summarize the existing evidence quantifying the concordance of qualitative BS in the presence or absence of clinical CRPS 1.

Data sources: We searched Medline, Embase, Dare and the Cochrane Library and screened bibliographies of all included studies.

Study eligibility criteria: We selected diagnostic studies investigating the association between qualitative BS results and the clinical diagnosis of CRPS 1. The minimum requirement for inclusion was enough information to fill the two-by-two tables.

Results: Twelve studies met our inclusion criteria and were included in the meta-analysis. The pooled mean sensitivity of 12 two-by-two tables was 0.87 (95% CI, 0.68-0.97) and specificity was 0.69 (95% CI, 0.47-0.85). The pooled mean sensitivity for the subgroup with clearly defined diagnostic criteria (seven two-by-two tables) was 0.80 (95% CI, 0.44-0.95) and specificity was 0.73 (95% CI, 0.40-0.91).

Conclusions: Based on this study, clinicians must be advised that a positive BS is not necessarily concordant with presence of absence or CRPS 1. Given the moderate level of concordance between a positive BS in the absence of clinical CRPS 1, discordant results potentially impede the diagnosis of CRPS 1.