US of nerve entrapments in osteofibrous tunnels of the upper and lower limbs.
The diagnosis of nerve entrapment at osteofibrous tunnels relies primarily on clinical and electrodiagnostic findings. Recently, the refinement of high-frequency broadband transducers with a range of 5-15 MHz, sophisticated focusing in the near field, and sensitive color and power Doppler technology have improved the ability to evaluate peripheral nerve entrapment in osteofibrous tunnels with ultrasonography (US). In the upper limb, osteofibrous tunnels amenable to US examination include the carpal tunnel for the median nerve and the cubital and Guyon tunnels for the ulnar nerve. In the lower limb, these tunnels include the fibular neck for the common peroneal nerve, the tarsal tunnel for the posterior tibial nerve, and the intermetatarsal spaces for the interdigital nerves. High-resolution US allows direct imaging of the involved nerves, as well as documentation of changes in nerve shape and echotexture that occur in compressive syndromes. A spectrum of extrinsic causes of entrapment, such as tenosynovitis, ganglia, soft-tissue tumors, bone and joint abnormalities, and anomalous muscles, can also be diagnosed with US. With continued experience, it is likely that this technique will be increasingly used to evaluate nerve entrapment syndromes.
Martinoli
C
C
Department of Radiology R, University of Genoa, Largo Rosanna Benzi 8, I-16132 Genoa, Italy. martinoli@zeus.newnetworks.it
Bianchi
S
S
Gandolfo
N
N
Valle
M
M
Simonetti
S
S
Derchi
L E
LE
D001132:Arm / Q000294:innervation*; D002349:Carpal Tunnel Syndrome / Q000000981:diagnostic imaging; D004568:Electrodiagnosis; D006801:Humans; D007866:Leg / Q000294:innervation*; D008682:Metatarsal Bones / Q000000981:diagnostic imaging; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging; D009408:Nerve Compression Syndromes / Q000000981:diagnostic imaging*; D010543:Peroneal Nerve / Q000000981:diagnostic imaging; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging; D013581:Synovial Cyst / Q000000981:diagnostic imaging; D013641:Tarsal Tunnel Syndrome / Q000000981:diagnostic imaging; D013717:Tenosynovitis / Q000000981:diagnostic imaging; D014034:Toes / Q000294:innervation; D014159:Transducers; D017769:Ulnar Nerve Compression Syndromes / Q000000981:diagnostic imaging; D018608:Ultrasonography, Doppler; D018615:Ultrasonography, Doppler, Color