The purpose of this systematic review was to determine whether patients diagnosed with posterior canal (PC) BPPV, based on positional testing, and treated with a particle repositioning maneuver will show the resolution of benign paroxysmal positional nystagmus (BPPN) on the Dix-Hallpike Test performed 24 hours or more after treatment. Data were obtained from an electronic search of the MEDLINE, EMBASE, and CINAHL databases from 1966 through September 2009. The study topics were randomized controlled trials (RCTs), quasi-RCTs, the diagnosis of PC BPPV, treatment with the particle repositioning maneuver, and outcome measured with a positional test 24 hours or more after treatment. In 2 double-blind RCTs, the odds in favor of the resolution of BPPN were 22 times and 37 times higher in people receiving the canalith repositioning procedure (CRP) than in people receiving a sham treatment. This finding was supported by the results reported in 8 nonmasked quasi-RCTs. Studies with limited methodological quality suggested that a liberatory maneuver (LM) was more effective than a control; there was no significant difference in the effectiveness of the LM and the effectiveness of the CRP; the self-administered CRP was more effective than the self-administered LM; and the CRP administered together with the self-administered CRP was more effective than the CRP administered alone. The Brandt-Daroff exercises were the least effective self-administered treatments.
Randomized controlled trials provided strong evidence that the CRP resolves PC BPPN, and quasi-RCTs suggested that the CRP or the LM performed by a clinician or with proper instruction at home by the patient resolves PC BPPN. There were no data on the effects of the manoeuvres on outcomes relevant to patients.