MRT-measurements of muscle volumes of the lower extremities of youths with spastic hemiplegia caused by cerebral palsy

After long term of studies from our gait lab, the typical muscular dysbalances by all of our patients with cerebral palsy where pointed out. Now we wanted to examine using the MRT, weather the dysbalances of the hemiparetic musculoskeletal system also show up in discrepancies of the muscle volumes. The MRT slices of the lower extremities were segmented. From this cross sections the muscles volumes were derived. These where analyzed particularly with regard to asymmetries between spastic and healthy side. Hemiparetic patients showed reduced volumes of all muscles on the paretic leg in comparison to the healthy side. The muscles of the thigh of the paretic leg were reduced to 84% in the mean over all muscles and in comparison to the healthy leg. The volume of the muscles of the shank was reduced to 72%, significantly more than the muscles of the thigh. Concerning flexor and extensor muscles located at thigh and shank of the paretic leg there was found significantly the same relative deficit of the muscle volume. Examining the muscle volumes of subjects with different neurogene foot deformities, significant differences of the volume reduction of single muscles appeared within the lower leg.