Arcade of Struthers

The arcade of Struthers is a thin fibrous aponeurotic band extending from medial head of triceps to medial intermuscular septum situated approximately 6-10 cm proximal to medial epicondyle of the humerus. In most cases this structure is due to a thickening of brachial fascia .

NB: This structure should not be confused with the ligament of Struthers.

Gross anatomy

Relations

• roof and medial border
  • thickened deep investing fascia of the arm
• anterior border
  • medial intermuscular septum
• posterior border
  • internal brachial ligament
• lateral border
  •  humerus covered by deep fibers of the medial head of triceps, minor posterior to the long head of triceps near its origin

Variant anatomy

• the arcade may be absent 
• the arcade may come from the internal brachial ligament
• the arcade may be due to a thickened medial intermuscular septum

Related pathology

​Under normal conditions, the arcade is not a site for ulnar nerve entrapment, but following anterior transposition procedures, the arcade of Struthers can cause entrapment as the ulnar nerve remain tethered proximally and in some cases implicated as a cause for failed cubital tunnel surgery.

History and etymology 

The arcade of Struthers was not actually documented by Sir John Struthers  who described the ligament of Struthers. Later researchers found the structure, however, the discovery was not without controversy, with some groups claiming it did not exist .