A Study Concerning The Relationship Between Knee Skin Temperature And Serum Inflammatory Markers Following Unilateral Primary Total Knee Arthroplasty

Objective To observe the dynamic changes of knee skin temperature and serum inflammatory markers following unilateral primary total knee arthroplasty and study the relationship between them.MethodsFrom 2013 August to 2014 October, patients who have undergone unilateral primary total knee arthroplasty because of serious knee osteoarthritis were concluded in our study. The doctor of traditionanal Chinese medicine dialectical to "liver ad kidney deficiecy".The excluded criteria included patients who were suffering from knee skin diseases such as scleroderma, psoriasis, neurodermatitis and erythromelalgia, taking part in other clinical trials, with patellar replacement and other out of control factors. We measured and observed the bilateral knee skin temperature on preoperative day and postoperative1,3,5,7,14 days,1,3,6,12 months. A comparison of knee skin temperature was made between the operated knee and the control one. The temperature were measured at fore points at the level of upper and lower border of the patella, the mean of the four readings was taken as the final temperature. We also monitored and analyzed the changes of CRP and ESR on the preoperative day and postoperative 1,3,5,7,14 days,1,3months. According to the results, we analyze the relationship between the knee skin temperature and serum inflammatory markers.ResultsAccording to the diagnostic of Chinese and western medicine, there were 86 patients received our study. The result showed that the knee skin temperature and serum inflammatory markers were significantly raised at the 5-7 days. The changes of CRP level is most sensitive, it will reached to the peak 2-3 days postoperative and gradually decreased.ESR level raised slower compared with CRP, it will reached to the peak 5-7 days postoperative and returned to the pre-operative level at 3 months. The operated knee skin temperature began to rise 1 day postoperative and gradually decreased 1 month later, it returned to the pre-operative level about 6-12 months after operation. The control knee skin temperature will reached to the peak 2-3 days postoperative and gradually decreased, it returned to the pre-operative level about 3months postoperative. Difference in knee temperatures was significantly elevated at the 5-7 days (= 3℃) and returned to the pre-operative level at 6-12 months(=1℃).There was a slight-middle increased in other periods of time (1℃-3℃).ConclusionThe mechanism of elevated knee skin temperature following TKA is still unclear.The acute trauma post-operation and then increased infiltration of the inflammation may contributed to the development of this symptom. In the early stage post operation (1-2 weeks), acute trauma occupies the leading factor because of the acute inflammatory reaction. In the middle stage post operation (1-2 months), there are many compound factors affect the knee skin temperature.In the late stage period (6-12 months), chronic inflammation caused by implant material wear particles may be attributed to the knee skin temperature increase.