The controversial arcade of Struthers.

BACKGROUND: The occurrence, incidence, and relevance of the arcade of Struthers as a point of compression of the ulnar nerve at the elbow region are still controversial. This study was conducted to determine the incidence of the arcade of Struthers on anatomical dissections and to analyze the data from the literature concerning this anatomical structure.

METHODS: The medial surface of the distal third of the arm was dissected in 60 limbs of frozen nonfixed cadavers, and the region was surveyed for the existence of musculotendinous and fibrous structures resembling an arch. When present, its appearance, extension, distance from the medial humeral epicondyle, and relation with the ulnar nerve were recorded.

RESULTS: A musculotendinous arcade, defined as arcade of Struthers, was identified in 8 limbs (13.5%). The extension of the arcade ranged from 2.5 to 5.0 cm (median 3.75 cm), and the distance between its distal limit and the medial humeral epicondyle ranged from 3 to 10 cm (median 6.82 cm). No evidence of ulnar nerve compression was found in the specimens where an arcade was identified.

CONCLUSION: Although the use of the term arcade of Struthers seems to be historically incorrect, this relatively rare anatomical structure does exist. Well recognized as a potential secondary site of compression of the ulnar nerve at the elbow in patients submitted to anterior transposition surgery, its importance as a primary site of compression probably has been underestimated.