Henry H. Ong1, Joseph J. Sarver2,
Jason E. Hsu2, Louis J. Soslowsky2, Felix W. Wehrli1
1Laboratory for Structural NMR Imaging,
Department of Radiology, University of Pennsylvania School of Medicine,
Philadelphia, PA, United States; 2McKay Orthopaedic Research
Laboratory, University of Pennsylvania, Philadelphia, PA, United States
Tendons
are comprised of parallel collagen fibers that connect muscles to bone.
Collagen-associated water has anisotropic rotational motion, which gives rise
to residual dipolar splitting in 1H NMR. Double-quantum filtered (DQF) NMR
and MRI can be used to observe the splitting and study the biophysical and
structural properties of tendon. Here, we modified a DQF 1D spectroscopic
imaging sequence to obtain 1H DQF spectra along the axis of the flexor
digitorum profundus (FDP) tendons from rat hind limbs and show spectral
differences in the region that wraps under the calcaneus, which experiences
compressive forces.