抄録
Purpose: The circadian rhythm in deep body temperature is characterized by a lower temperature at night. The purpose of this study was to analyze the skin temperature of normal shoulders and those with rotator cuff tears (RCTs), and to determine the relationship between the shoulder skin temperature and night pain in shoulders with RCTs.
Methods: The subjects were 13 hospitalized patients with RCTs: 12 patients were unilateral and one bilateral. Eight of the 12 contralateral shoulders of unilateral RCTs showed no abnormalities on MRI without any clinical symptoms, and thus were used as normal shoulders. We attached the probe of a TL 72 portable thermometer to the anterior aspect of each shoulder and measured the temperature every 5 minutes from 12: 30 in the afternoon to 9: 30 the next morning. After the moving averages over a one-hour range were calculated, the differences between temperatures at one-hour intervals from 13: 00to 9: 00 were evaluated with an ANOVA. Eight patients reported night pain during the temperature measurements.
Results: Both in the normal and RCT shoulders, skin temperatures at night were significantly lower than those during the daytime(p<0.05). Night pain was frequently observed between midnight and early in the morning when the temperature was at its lowest.
Conclusion: The shoulder skin temperature of both the normal and RCT shoulders showed a circadian rhythm with a low temperature during the night. Night pain was frequently observed at and around the lowest skin temperature. Low temperature during the night may be related to the occurrence of night pain.
