The NHS warns that if you experience 'tingling', particularly in two specific areas, it could be time to dial 999. In their guidance about back pain, they warn that this discomfort - combined with a tingling sensation - could be a sign of a serious condition. Back pain is frequently triggered by injuries such as muscle strains or medical conditions like slipped discs, sciatica (a trapped nerve), or ankylosing spondylitis. Whilst back pain is commonplace and often clears up on its own, in rare