A 55-year-old man has been found lying injured in the road in Whitburn.
Officers found him on the southbound carriageway of Blaeberry Road, 500 yards south of the A705 at around 8.45pm last night.
He had sustained minor injury to his left hip and was taken to the Royal Infirmary of Edinburgh for observation.
Enquiries into how the man came to be on the roadway are ongoing and anyone who can assist police with their investigation is asked to come forward.
Road Policing Sergeant Gary Taylor said: “We do not know at this time how the man has sustained his injury and we are keen to hear from motorists who were on the road on Sunday evening and remember seeing anything that can help establish what has happened.
“Anyone with information in relation to this enquiry is asked to contact police immediately on 101.