The structure of peripheral nervous system diseases is reviewed by analyzing 941 in- and outpatient case histories. Of this number, 57.34% of the patients had radicular syndromes, 16.17%, acute injuries of nerves and plexuses, and 22.66%, tunnel and other compression syndromes. Cases of polyneuropathy and other disorders accounted for only 3.83%. A total of 21.46 cases with nontraumatic mechanical damage to nerves are analyzed in detail. In 87.88%, these syndromes involved upper and in 12.12% lower extremities. Syndromes of the carpal canal (43.01%), ulnar canal (14.72%), cervical neurovascular compression (12.95%), and tarsal canal (5.08%) occurred most frequently. A wide variety of other syndromes made up only 24.24% of all compression syndromes.