- See: Anterior Interosseous Nerve Sydrome:
- Site of Proximal Forearm Compression;
- supracondylar process of the humerus and struther's ligament:
- median nerve may be compressed as it passes under the bondy spur
- pt c/o of weak hand grip and in pronating, & tingling in lateral digits;
- there may be objective weakness in the pronator teres, FCR, FPL, FDS, and lateral half of FDP, and thenar mucles;
- presence of pronator weakness distinguishes this syndrome from pronator and anterior interosseous syndromes;
- nerve conduction studies may have shown slowing in the conduction velocity in the median nerve in the arm;
- ref: Images in clinical medicine. Processus supracondylaris humeri.
- lacertus fibrosus:
- at front of elbow, median nerve lies behind bicipital aponeurosis (lacertus fibrosus) and in front of the brachialis;
- one must suspect the lacertus fibrosis with pain in the forearm w/ resisted elbow flexion beyond 120 deg;
- it can also be caused by pressure from the origin of the FDS;
- pronator teres: (pronator teres compression syndrome)
- w/ compression at this site, pts may complain of pain following resisted flexion of the FDS to the long finger;
- one should suspect compression of meidan nerve by head of pronator teres when a patient complains of pain with increased activity;
- check this with forced pronation and wrist flexion;
- elarged median artery can also cause the pronator syndrome as well as compress the median nerve at the wrist;
- sublimis bridge:
- median nerve then passes under the fibrotendinous arcade that represents the origin of the FDS muscle;
- median nerve descends in the forearm adherent to the undersurface of FDS and lying superficial to the FDP;
- EMG may show denervation potentials in median innervated muscles in the forearm and hand;
- clinical syndrome may be associated with symptoms and signs of ischemia in the distribution of the brachial artery;
- bony process may or may not be palpable;
- tangential or oblique views of humerus may show supracondylar process to greater advantage than routine AP & lateral views;
- brachial arterogram may be necessary if vascular comprimise is possible
- surgical therapy consists of excision of Struther's ligament and removal of the bony spur