Horizontal semicircular canalith jam mimicking acute vestibular syndrome: physiotherapy-guided diagnosis and treatment in three cases

Canalith jam (CJ) is a rare variant of benign paroxysmal positional vertigo (BPPV), resulting from otoconial obstruction of endolymph flow. It causes persistent, direction-fixed nystagmus (DFN) and can mimic acute vestibular syndrome (AVS), including vestibular neuritis (VN) or stroke. To describe the clinical and infrared video-Frenzel (IRVF) based diagnosis of horizontal semicircular canal (HSC) canalith jam (HSCCJ), a subtype of CJ, and to highlight the role of physiotherapy-guided bedside maneuvers in its successful management. Three patients (aged 50, 55, and 62) presented with positionally triggered acute vertigo. Patients 1 and 3 had sustained DFN consistent with AVS, whereas patient 2 developed persistent DFN during positional testing. The diagnosis of HSCCJ was established through positional tests [supine roll test (SRT), bow and lean test (BLT)] and assessment of DFN using IRVF goggles. All patients underwent a physiotherapist-administered head-shaking maneuver (HSM) in the yaw plane, performed with 30° of neck flexion. One patient also received the Gufoni maneuver (GM). Maneuvers were guided by real-time oculomotor responses recorded via videonystagmoscopy. All patients experienced complete resolution of symptoms and nystagmus within 4 hours, confirmed by repeat testing at 4 and 24 hours. Transient nausea and vomiting were the only adverse effects observed. Although the diagnosis of HSCCJ depends on clinical and oculographic evaluation, physiotherapy-guided HSM is a simple, safe, and effective bedside intervention. Incorporating this approach into vestibular rehabilitation (VR) protocols may enhance outcomes in atypical BPPV.