Date	Event	Description
28 July 2016	Review declared as stable	See Published notes.
7 March 2016	New citation required but conclusions have not changed	The conclusions of the review remain unchanged.
16 October 2015	New search has been performed	This updated review used refined exclusion criteria (exclude studies with follow‐up of <48hrs) (see Differences between protocol and review). This resulted in the exclusion of 4 studies from this update that had been included in previous versions of this review (Meier 2009; Raja 1991; Verdugo 1995; Wehnert 2002). We also updated the data analysis that included consideration of the minimally important difference (as per OMERACT 12 group recommendations) and evaluation of the quality of evidence using the GRADE approach.
26 June 2013	New search has been performed	This updated review used an expanded search strategy, updated Risk of Bias assessment, and updated inclusion criteria. These changes resulted in inclusion of 10 additional studies compared with the initial review (n = 363 additional participants); two studies compared LASB to a placebo/inert treatment (Aydemir 2006; Price 1998), the remaining nine studies compared LASB with an active treatment [Bonelli 1983; Carroll 2009; Meier 2009; Nascimento 2010; Raja 1991; Toshniwal 2012; Wehnert 2002; Zeng 2003) or investigated the effect of adding LASB to an active treatment (Rodriguez 2005). Despite these methodological updates and inclusion of new studies, the conclusions of the review remain unchanged; there is a dearth of published evidence for LASB and the available evidence suggests lack of efficacy. Readers of the original review would benefit from reading this update as new evidence is provided for treatment comparisons between LASB and other active interventions (for example, intravenous regional anesthesia).
26 June 2013	New citation required but conclusions have not changed	Despite methodological updates and inclusion of new studies, the conclusions of the review remain unchanged; there is a dearth of published evidence for LASB and the available evidence suggests lack of efficacy.
3 October 2011	Amended	The following changes have been made to the methodology of the protocol. We have made them all to bring the protocol up to date with the current PaPaS author guidelines: We have chosen to adopt a modified version of the Cochrane ROB tool with additional criteria added in response to the recommendations of Moore et al. (2010). As such we have added 2 additional criteria “Size” and “Duration” using the thresholds for judgement suggested by Moore 2010. We have not added the “Outcome” criteria as this is covered already by our choice of primary outcome measures. We have rewritten the data synthesis/ analysis sections to fit the current RevMan headings. We now specify that we will calculate Risk Ratio for achieving a moderately important benefit (30% or more) or a substantially important benefit (50% or more) and have specified time windows for short, medium and long term follow up. We suggest the following preplanned subgroup analyses where adequate data allow: CRPS I vs II, Adults vs children and single vs continuous blockade. We have added a planned sensitivity analyses, where data are sufficient, to allow testing of the effect of including/ excluding studies whose risk of bias is unclear or high.
3 October 2011	Amended	The Background section has been substantively rewritten to fit the headings now suggested in RevMan.
22 September 2011	Amended	Searching other resources ‐ unpublished studies: We have expanded this search strategy to also include clinical and controlled trial registers, such as http://www.controlledtrials.com/, the Australian New Zealand Clinical Trials Register (http://www.anzctr.org.au/), and a European Clinical Trials Register (https://www.clinicaltrialsregister.eu/).
21 September 2011	Amended	We have inserted a new Table (under other Tables) that provides the new Budapest criteria for diagnosing CRPS.
21 September 2011	Amended	We have added new search terms to the search strategy that will make it more sensitive and conforms to updates in treatment (for example, Botox now being used for sympathetic chain blockades). Also attached is an updated search strategy for Medline, created in collaboration with Jane Hayes from PaPaS.
21 September 2011	Amended	Methods: selection of studies. Two independent reviewers will screen the titles and abstracts of the search results in order to determine which full text articles to retrieve. This is changed from one reviewer.
21 September 2011	Amended	Addition of new criteria for considering studies for this review (Types of interventions).
21 September 2011	Amended	Addition of new criteria for considering studies for this review (Types of participants).
9 November 2009	Amended	Contact details updated.
30 October 2008	Amended	Converted to new review format.