We studied the MRI findings of a frozen shoulder in three different phases. Forty-one frozen shoulders were available for this study. The mean age of the patients was 58 years (range,43 to 77 years). The mean range of elevation of the shoulders was 118 degrees (range,80 to 140 degrees). There were 10 shoulders in the acute phase (less than 2 months),16 in the subacute plase (2 to 3 months),15 in the chronic phase (4 to 12 months). Oblique coronal, oblique sagittal, and axial sequences were made with the fast spin-echo technique using a 0.5-tesla MR Vectra unit. On T2-weighted images, high signal intensities (HIS) in the glenohumeral joint (GHJ), the subacromial bursa (SAB) and the bicipital groove (BG) were analyzed, and then the contraction of the axillary pouch was evaluated.
HIS at the GHJ was moderate in 40%, slight in 20% and none in 40% of the shoulders in the acute phase; in 0%, in 63% and in 37%, respectively, in the subacute phase; and in 7%, in 40% and in 53%, respectively, in the chronic phase. HIS at the SAB was moderate in 0%, slight in 30% and none in 70% of the shoulders in the acute phase; in 0%, in 25% and in 75%, respectively, in the subacute phase; and in 0%, in 27% and in 73%, respectively, in the chronic phase. HIS at the BG was moderate in 30%, slight in 60% and none in 10% of the shoulders in the acute phase; in 25%, in 19% and in 56%, respectively, in the subacute phase; and in 13%, in 40% and in 47%, respectively, in the chronic phase. Contraction of the axillary pouch was observed in 20% of the shoulders in the acute phase,69%in the subacute phase, and 73% in the chronic phase.
In conclusion, there were increased amounts of fluid at the GHJ and BG in the acu, t eb upt haosnely a small amount at the SAB. Shoulder stiffness may be caused by contraction of the GHJ capsule which develops as the intraarticular synovitis resolves.
