Upweighting Proprioceptive Information for Treatment of Mal de Mer: A Case Report

This case report describes a 46 year old female with complaints of dizziness and decreased ability to complete activities of daily living although aboard a U.S. Navy ship. She was unable to walk unsupported and her ability to work at a computer was severely limited because of the severity of her symptoms. She had a long history of motion sickness, predominantly seasickness (mal de mer), Eustachian tube dysfunction, and bilateral tympanic membrane perforations. Finding minimal benefit from pharmacological interventions, she was evaluated and diagnosed with seasickness by a physical therapist. The initial interventions focused on gaze stabilization exercises, but were limited in efficacy because of the continuous nature of shipboard motion resulting in needing extended times in a supine position with a foot grounding her on the floor for symptom resolution. Through the application of a sensory reweighting system improvised from available clinic supplies, the patient's symptoms reduced to the point of being able to walk unsupported and engage with VOR habituation exercises although on the ship. This case is unique in that the patient's seasickness did not resolve with typical pharmacologic or physical therapy interventions, so innovative strategies were used to modify her sensory weighting to mitigate her symptoms. This case report may provide other clinicians in austere settings (shipboard) with a non-pharmacological option for the treatment of unresolving seasickness.