Double-blind randomized trial on the efficacy in a short-time follow-up of the “Quick Liberatory Rotation” maneuver in treating posterior canal BPPV

This double-blind randomized study evaluates the efficiency of the Quick Liberatory Rotation maneuver (QLR) in solving signs and symptoms of Posterior Canal BPPV in a short time follow-up comparing the efficiency of QLR vs. a sham maneuver (“Fake QLR”).The study was performed at an input-output tertiary center for balance disorders. From January to September 2012, 200 patients with signs and symptoms of Posterior Canal BPPV respected the inclusion criteria in the study. The diagnosis was based on observation with binocular infrared videonystagmoscopy of the paroxysmal torsional and upbeat nystagmus evoked through the Dix-Hallpike test (DHT). Patients were divided in two groups, 100 in the group treated by QLR (Group 1) and 100 in the control group treated by “Fake QLR” (Group 2). Before the treatment, they self-evaluated a Visual Analogue Score on their vertiginous complaints (V-VAS). Patients were controlled one hour after the treatment by a blinded examiner about the first phase of the study through DHT, the Straight head-hanging positioning test and the Head Roll test in supine position and assessed again with V-VAS. Patients with a persisting positive DixHallpike test were subsequently treated through QLR. The main outcome measure is the number of patients treated through QLR or “Fake QLR” with a negative DHT one hour after the first treatment. At the post-procedure check, 79 patients from Group 1 presented a negative DHT with little or no subjective symptoms, whereas all the patients of Group 2 presented persistence of a positive DHT. The presence of the secondary nystagmus during QLR (“liberatory” nystagmus) was significantly correlated with a negative DHT at the post-procedure control. In Group 1 preand posttreatment V-VAS differences were significant; post-treatment V-VAS differences were significant in Group 1 vs. Group 2. In a short time follow-up QLR is an effective treatment for Posterior Canal BPPV when compared to a sham maneuver. DOI : 10.14302/issn.2379-8572.joa-14-418 Running title: Double-blind randomized trial on QLR Corresponding Author: Luigi Califano Via A. Lepore a4 bis 82100 Benevento 0039 0824 311467 luigi.califano@tin.it vertigobn@hotmail.com Key-words: Posterior canal BPPV; Quick Liberatory Rotation maneuver; Canalolithiasis; BPPV therapy Freely Available Online www.openaccesspub.org | JOA CC-license DOI : 10.14302/issn.2379-8572.joa-14-418 Vol-1 Issue 1 Pg. no.2 Introduction. Benign Paroxysmal Positional Vertigo (BPPV) is the most common vertiginous syndrome. Adler (1) first described it; Barany reported a case citing his assistant Carlefors . The concept of positional vertigo was finally introduced into the clinical practice by Dix and Hallpike: "Two things are quite clear. Firstly, the pathological process, wherever or whatever it is, is essentially a benign or self-limiting one. Secondly, the lesion, whatever its nature, is limited to the vestibular apparatus and here the term "vestibular" is used in its widest sense, to include the labyrinth, vestibular nerve and its central connexions". The pathogenetic mechanism was postulated by Shucknecht (4) who first described the presence of basophile elements (otoliths) adhering to the cupula of the posterior semicircular canal in individuals who had suffered from this disease. From this observation the word "cupulolithiasis" was born. In 1979 Hall hypothesized the mechanism of "canalolithiasis"; in 1985 Pagnini and McClure described, individually, lateral canal BPPV. In 1980 Brandt and Daroff (8) introduced a therapeutic maneuver for BPPV based on repetitive lateral positioning of the body passing each time from the sitting position and Epley (9) formulated the Canalith Repositioning Procedure for Posterior Canal BPPV; in 1988 Semont introduced his maneuver for Posterior Canal BPPV ; in 1989 Toupet (12) optimized the Semont Maneuver (SM). Epley Maneuver (EM) and SM allow an effective treatment, sometimes in a single session, of Posterior Canal BPPV, thus affirming the concept of "liberatory therapy"; both EM and MS are widespread, since they are very effective, easy to perform, with minor side effects compared to therapeutic benefits. Furthermore, in most cases BPPV evolves towards a spontaneous resolution in few days or weeks ; therefore, at least a part of the successes attributed to therapeutic maneuvers could be effects of the natural benign evolution of the disease. In 1992 Guyat (14) introduced the concept of “Evidence Based Medicine” (EBM): any treatment should be evaluated on the basis of clinical evidence by the comparison with other treatments, with placebo and with no treatment regimen; clinical evidence is classified in a grade system as “levels of evidence” . The Cochrane Collaboration, an international network which collaborates to help healthcare providers, policymakers, patients, their advocates and carers, prepares the largest collection of records of randomized controlled trials in the world, published as part of The Cochrane Library. Cochrane reviews stressed that EM and SM were often not analyzed through studies that reflect the EBM criteria for the validation of such treatments; the last Freely Available Online www.openaccesspub.org | JOA CC-license DOI : 10.14302/issn.2379-8572.joa-14-418 Vol-1 Issue 1 Pg. no.3 review (16) analyzed only five trials involving 292 participants for EM. It concludes that "There is evidence that Epley maneuver is a safe, effective treatment for posterior canal BPPV, based on the results of five mostly small randomized controlled trials with relatively short follow-up". A recent double-blind randomized trial on short-term efficacy of SM , on the intentions of the authors, has brought the level of effectiveness rating of SM for posterior canalolithiasis to level B, defined as evidence based on “randomized controlled trials or diagnostic studies with minor limitations; overwhelmingly consistent evidence from observational studies" . In 2003 we proposed the "Quick Liberatory Rotation Maneuver" (18) (QLR) for treating posterior canal BPPV; QLR uses the speed of execution of SM but performs the movement in the frontal plane, as in EM (Fig.1). In a comparative study of efficacy in the short and medium term between QLR, Parnes maneuver and SM, we demonstrated the equal clinical efficacy of these treatments . Our maneuver, based on a quick rotation of the head and the body of the patient, has been replicated by other Authors: “hybrid approach through Gans maneuver” , “hybrid maneuver” . Our original paper is not cited in these articles.

Adler (1) first described it; Barany reported a case citing his assistant Carlefors (2) . The concept of positional vertigo was finally introduced into the clinical practice by Dix and Hallpike: "Two things are quite clear. Firstly, the pathological process, wherever or whatever it is, is essentially a benign or self-limiting one. Secondly, the lesion, whatever its nature, is limited to the vestibular apparatus and here the term "vestibular" is used in its widest sense, to include the labyrinth, vestibular nerve and its central connexions" (3) .
The pathogenetic mechanism was postulated by Shucknecht (4) who first described the presence of basophile elements (otoliths) adhering to the cupula of the posterior semicircular canal in individuals who had suffered from this disease. From this observation the word "cupulolithiasis" was born.
In 1980 Brandt and Daroff (8) introduced a therapeutic maneuver for BPPV based on repetitive lateral positioning of the body passing each time from the sitting position and Epley (9) formulated the Canalith Repositioning Procedure for Posterior Canal BPPV (10) ; in 1988 Semont introduced his maneuver for Posterior Canal BPPV (11) ; in 1989 Toupet (12)  Furthermore, in most cases BPPV evolves towards a spontaneous resolution in few days or weeks (13) ; therefore, at least a part of the successes attributed to therapeutic maneuvers could be effects of the natural benign evolution of the disease.
In 1992 Guyat (14) introduced the concept of "Evidence Based Medicine" (EBM): any treatment should be evaluated on the basis of clinical evidence by the comparison with other treatments, with placebo and with no treatment regimen; clinical evidence is classified in a grade system as "levels of evidence" (15) . A recent double-blind randomized trial on short-term efficacy of SM (17) , on the intentions of the authors, has brought the level of effectiveness rating of SM for posterior canalolithiasis to level B, defined as evidence based on "randomized controlled trials or diagnostic studies with minor limitations; overwhelmingly consistent evidence from observational studies" (15) .

In 2003 we proposed the "Quick Liberatory Rotation
Maneuver" (18) (QLR) for treating posterior canal BPPV; QLR uses the speed of execution of SM but performs the movement in the frontal plane, as in EM (Fig.1). In a comparative study of efficacy in the short and medium term between QLR, Parnes maneuver (19) and SM, we demonstrated the equal clinical efficacy of these treatments (18) . Our maneuver, based on a quick rotation of the head and the body of the patient, has been replicated by other Authors: "hybrid approach through Gans maneuver" (20) , "hybrid maneuver" (21) . Our original paper is not cited in these articles.

Objectives.
The aim of the present study is to evaluate through a controlled, randomized, double-blind study the shortterm (one hour) efficacy of QLR compared with a "fake QLR" which does not cause a significant shift of otoliths from the position in which they are located after the Dix-Hallpike Test (DHT): therefore, the "fake-QLR" (Fig.2) can be considered a sham-maneuver with a possible placebo effect.
Outcomes were evaluated one hour after the treatment with QLR or "fake QLR": 1. Primary outcome: conversion of a positive DHT into a negative DHT by each maneuver.
2. Secondary outcome: reduction of subjective can also interfere. We included in the study only patients with no prior history of BPPV to minimize these factors, which may already be structured in patients with previous, similar experiences.

Patients and methods
From January to September 2012, 298 patients with a diagnosis of Posterior Canal BPPV were observed.
The clinical examination consisted of the execution of a  After the post-treatment check, patients were informed which maneuver they had received and, in cases of persisting positive DHT, QLR was performed.
All patients were invited to further check-ups every two days until a negative DHT was observed and thirty days after the last maneuver, but these points are not included in the objectives of the present study.
The statistical analysis was conducted using the Wilcoxon test and the Pearson's chi-square Test (22) via SPSS software.
Results 112 women and 88 men, mean age 58.7 ± 9.76 years, were included in the study.
There were no significant differences between the two groups in mean age (p = 0. Clinical data are summarized in Table I.

Phase I: Therapy
Group 1. 100 patients were treated with a single session  The difference of the primary outcome among patients who presented or did not present the secondary nystagmus during QLR was statistically significant, in the sense that patients with secondary nystagmus resulted disease-free more frequently than those who did not (χ 2 =45.49, df=1, p <0.0001) ( Table II).

Discussion
BPPV is the most frequent vertiginous syndrome, with a life-time prevalence of 2.4% (23) .
The literature emphasizes how early physical therapy reduces the costs related to the management of patients affected by BPPV (36) , decreases relapses and reduces the fear of vertigo, which often influences the quality of life of dizzy patients (37) .
The main objection made to the majority of the existing clinical trials is that they usually do not compare the treatment to other ones, to a placebo treatment or to a no treatment regimen. Although BPPV frequently tends to a spontaneous resolution (13) , the success rate of therapeutic maneuvers is much higher than the effects of the spontaneous resolution (32) . Bhattacharyya et al. (15) (17) . Moreover, QLR improved subjective symptoms, evaluated through V-VAS, when compared to the group treated through "fake QLR" in which, instead, subjective symptoms were largely unchanged.
After QLR, in 79% of cases we observed the resolution of signs and symptoms in a one-hour follow-up, a time frame in which a spontaneous resolution is extremely unlikely, especially considering that patients remained in a locked sitting position for the entire time between treatment and control.
Our study showed the effectiveness of QLR in solving signs and symptoms of Posterior Canal BPPV in a high rate of cases when compared to a sham maneuver: it is our belief that the study provides a Class B evidence of efficiency of QLR in treating Posterior Canal BPPV.