Biphosphonates for the therapy of complex regional pain syndrome I--systematic review.
OBJECTIVE
Several studies found that biphosphonates counteract locally increased bone resorption and associated pain in patients with complex regional pain syndrome I (CRPS I). We performed a systematic review of all randomised controlled trials to assess the benefit of biphosphonates in the treatment of CRPS I patients with bone loss.


METHODS
We searched Medline, Embase (April 2007) and the Cochrane Library and screened bibliographies of included studies.


METHODS
We selected randomised trials comparing biphosphonates with placebo, with the goal of improving pain, function and quality of life in patients with CRPS I. Two reviewers independently assessed trial eligibility and quality, and extracted data. Where data were incomplete or unclear, conflicts were resolved with discussion and/or trial authors were contacted for further details. We calculated the study size weighted pooled mean reduction of pain intensity (measured with a visual analogue scale (VAS)).


RESULTS
Four trials of moderate quality fulfilled our inclusion criteria. In respect to function and quality of life there was a trend in favour of biphosphonates but differences in outcome assessment impeded pooling of results. Two trials provided sufficient data to pool pain outcomes. Biphosphonates reduced pain intensity by 22.4 and 21.6mm on a VAS after 4 and 12 weeks of follow-up. Data on adverse effects were scarce.


CONCLUSIONS
The very limited data reviewed showed that bisphosphonates have the potential to reduce pain associated with bone loss in patients with CRPS I. However, at present there is not sufficient evidence to recommend their use in practice.
Brunner
Florian
F
Department of Physical Medicine and Rheumatology, Balgrist University Hospital, Forchstrasse 340, 8008 Zurich, Switzerland. florian.brunner@balgrist.ch
Schmid
Annina
A
Kissling
Rudolf
R
Held
Ulrike
U
Bachmann
Lucas M
LM
D003627:Data Interpretation, Statistical; D004164:Diphosphonates / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic / Q000592:standards; D012019:Reflex Sympathetic Dystrophy / Q000188:drug therapy* / Q000523:psychology
D004164:Diphosphonates