Portsmouth sign

Portsmouth Sign

Portsmouth Sign (pronunciation: /ˈpɔːrtsməθ saɪn/) is a medical term used to describe a specific clinical sign in neurology. The term originates from the city of Portsmouth in the United Kingdom, where it was first described.

Definition

The Portsmouth Sign is a clinical sign observed in patients with certain neurological disorders, particularly those affecting the motor neurons. It is characterized by an involuntary flexion of the thumb into the palm when the patient's hand is at rest.

Clinical Significance

The Portsmouth Sign is often indicative of a lesion in the corticospinal tract, a part of the central nervous system that plays a key role in motor control. It is particularly associated with conditions such as Amyotrophic Lateral Sclerosis (ALS) and Primary Lateral Sclerosis (PLS).

Related Terms

Babinski Sign: A similar neurological sign, characterized by the upward movement of the big toe and fanning of the other toes when the sole of the foot is stimulated.
Hoffmann's Sign: Another neurological sign, characterized by the involuntary flexion of the thumb and index finger when the middle finger is flicked.

Etymology

The term "Portsmouth Sign" is named after the city of Portsmouth, where it was first described by neurologists in the early 20th century. The exact origin of the term is not known, but it is believed to have been coined by a local physician who noticed the sign in several of his patients.