Vertigo returning to the sitting position after the Semont manoeuvre. Is it a prognostic symptom?

Benign paroxysmal positional vertigo (BPPV) is a frequent benign vestibular condition usually managed with particle repositioning manoeuvres, such as Semont manoeuvre (SM). Since few authors have described prognostic aspects of liberatory manoeuvres, the purpose of the present study was to investigate the possibility of considering vertigo in the final sitting position of the SM as a prognostic symptom in the outcome of posterior BPPV. One hundred and thirteen patients with diagnosis of unilateral posterior BPPV were taking into account in our retrospective cohort study: 41 men and 72 women, aged 22 to 85 years. All were submitted to one repositioning SM and afterwards controlled 3 to 5 days later by means of an additional Dix-Hallpike manoeuvre. The main outcomes investigated were the occurrence of Ny and vertigo in the different phases of the SM, as well as their characteristics in relation to outcome of the disease. Among all patients, 75 (66%) presented both orthotropic Ny and vertigo in the second SM position and 72% obtained a complete resolution of the disease after the liberatory manoeuvre. Contrarily, 17 subjects (15%) manifested vertigo in the final sitting position of the SM and among these, only 7 (41%) completely recovered from BPPV. According to our data, in case of sudden vertigo returning to the final sitting position of the SM, the failure rate of the liberatory manoeuvre was higher, even though not statistically significant: therefore, it can be considered as a negative prognostic factor of posterior BPPV after SM.