Several components of postural control are affected by benign paroxysmal positional vertigo but improve after particle-repositioning maneuvers: A systematic review and meta-analysis.

Only 9 of the 37 included studies used vestibular function tests to rule out another vestibular disorder, and 12 reported no screening at all, so the pooled patients include people with additional vestibular problems that can affect balance and the response to treatment - the authors name this as a limitation. Studies varied widely in how soon they first measured after treatment (from immediately to two weeks), how long people had had symptoms, and how many maneuvers were given. Age ranges were broad, and the authors could not always separate younger from older patients even though postural control changes with age. Small samples and different measurement methods blocked many analyses: several parts of the framework (biomechanical constraints, reactive postural responses, transitions and anticipatory control, and postural control with vestibular changes alone) rest on one or a handful of studies. Eight studies of treatment used a single-group pre-test/post-test design with no control group, so improvement after a maneuver could reflect natural recovery, repeated testing or the passage of time rather than the maneuver itself. The review took the earliest measurement after treatment, so it says nothing about whether gains hold in the longer term. Six case-control and quasi-experimental studies were excluded for high risk of bias, and in four of the included case-control studies the controls were not checked with diagnostic maneuvers for BPPV.

The authors declared no potential conflicts of interest with respect to the research, authorship and publication of the article. The work was funded by the Special Research Fund of Hasselt University (one grant for each of two authors), and by Maastricht University and Ziekenhuis Oost-Limburg Genk. No company that makes or sells a treatment or device is named as a funder.

Do not read this as showing that repositioning maneuvers restore balance. One-leg stance and older patients' limits of stability did not improve after treatment in this review, and the authors note that balance can stay poor even when positional testing is negative, which points to a coexisting vestibular disorder or persistent postural-perceptual dizziness.