Vibration imaging for localization of functional compartments of the extrinsic flexor muscles of the hand.
OBJECTIVE
To develop and test an MRI-based imaging technique for the localization of the functional compartments of the functionally finger-specific, yet anatomically indistinct, flexor muscles of the hand.


METHODS
A total of six normal healthy volunteers were involved in five studies in which individual fingers were vibrated with mechanical actuators and the resultant motion within the corresponding functional compartments of the flexor muscles, mechanically transferred through the structurally connected tendons, was imaged with a phase-contrast MR imaging technique that is highly sensitive to cyclic motion. The motion amplitude and relative phase relationship between the functional compartments of various muscles and fingers were obtained and analyzed from these images as a means to differentiate the various subcompartments.


RESULTS
The results show that this technique provides a detailed mapping of the regions of the complex flexor muscle compartments that correspond to each digit for both the flexor digitorum profundus and the flexor digitorum superficialis. The results also demonstrate the presence of mechanical interdependence between the flexor muscles.


CONCLUSIONS
It is concluded from the results that localization of the finger-specific subcompartments of the forearm flexor muscles can be performed with this technique.
Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Yogesh K
YK
Mariappan
Armando
A
Manduca
Kevin J
KJ
Glaser
Jun
J
Chen
Kimberly K
KK
Amrami
Richard L
RL
Ehman
D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D005385:Fingers / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D009038:Motion; D009068:Movement / Q000502:physiology; D018482:Muscle, Skeletal / Q000473:pathology*; D013710:Tendons / Q000473:pathology / Q000502:physiology; D014732:Vibration