The carpal tunnel, a narrow space closed distally by the anterior annular 
ligament of the wrist, and containing flexor tendons and the median nerve, is 
the most frequent site of tunnel syndromes, compression in the canal leading to 
medium nerve lesion. The carpal tunnel syndrome usually affects women aged 
between 40 and 60 years, and presents typically as parasthesia of the fingers, 
mainly at night, in the regions served by the median nerve, sometimes associated 
with hypoesthesia and difficulty in movements. Motor disorders, particularly 
affecting the thumb, occur during the advanced stages. Electrical tests may 
confirm diagnosis and enable assessment of severity. More than half the cases 
are idiopathic in nature, presenting as hypertrophy of the annular ligament and 
fibrous thickening in the canal, but other forms may be observed including those 
due to wrist injuries, anatomical anomalies, rheumatic affections, or tumours. 
Associated disorders may be Dupuytren's disease, cubital nerve compression in 
Guyon's canal, or nodular tendinitis leading to a trigger finger. Surgical 
treatment is simple and should be employed when medical measures fail. The nerve 
should therefore be liberated if parasthesia persists after two or three local 
corticoid infiltrations. After a wide exploratory incision, the nerve is freed 
along the total length of the canal and up to the distal extremity of the 
forearm. Results are excellent, 98 p. cent of patients being relieved of their 
pain. Persistent motor disorders require surgical intervention before amyotrophy 
and muscle weakness develops.