BACKGROUND: Although clinical investigations indicate that the limit of reversibility of rotator cuff muscles fibers type I and II @entity194 is grade 2 of @entity528 ( @entity528 ) according to the Goutallier computed tomography classification, little is known about the morphometric verification of these findings. METHODS: The supraspinatus tendon was detached from the greater tubercle and the infraspinatus and subscapularis in 12 @entity95 , and a 12-week observation period followed. This proved to be sufficient for development of grade >2 @entity528 of the supraspinatus tendon. The tendon was then reinserted. The animals were euthanized 24  weeks after tendon reconstruction. The sections of middle part of supraspinatus were stained for @entity859 triphosphatase reaction, and morphometric measurements were taken of type I and II muscle fiber diameters. The contralateral shoulders served as controls. RESULTS: The macroscopic inspection of the supraspinatus tendons revealed complete healing in all cases. No statistically significant differences were found between controls and operated-on shoulders for type I (P  =  .13) and type II (P  =  .55) muscle fibers. CONCLUSIONS: @entity194 and II muscle fibers in @entity95 supraspinatus muscle, characterized by grade >2 @entity528 according to the Goutallier computed tomography classification, is reversible after 24  weeks from reattachment of its tendon. A requirement for type I and II muscle fibers @entity1184 is a change in the biomechanical and functional conditions of the muscle after its tendon is reconstructed.

XXXX and II muscle fibers is reversible in the case of grade >2 fatty degeneration of the supraspinatus muscle: an experimental study in @entity95 .

@entity859 :: ('MESH:D000241', 'Chemical') :: ['adenosine'] @entity1184 :: ('MESH:D006984', 'Disease') :: ['hypertrophy'] @entity95 :: ('9986', 'Species') :: ['rabbits', 'rabbit'] @entity194 :: ('MESH:D001284', 'Disease') :: ['atrophy', 'Atrophy of type I'] @entity528 :: ('MESH:D009410', 'Disease') :: ['FD', 'fatty degeneration']
@entity194 :: (MESH:D001284,Disease) :: ['Atrophy of type I']
