良性腱鞘巨细胞瘤文献报告不多 ,而发生于膝关节及臀部的更属罕见。在临床上往往认识不足被误诊为囊肿或关节鼠等。近 5年来作者遇到 3例 ,2例术前诊断为膝关节赘生物 ,其中 1例术后出现持续关节积液 ,经多次抽液无效 ,再次行关节滑膜大部切除而愈 ,1例术前诊断坐骨结节囊肿 , Benign tendon sheath cell tumor report little literature, but occurred in the knee and buttocks is even rare. In clinical practice, often misunderstood as misdiagnosed as cysts or joint mice. In the past five years, the authors encountered 3 cases, 2 cases of preoperative diagnosis of knee neoplasms, including 1 case of persistent joint effusion after repeated pumping invalid, again synovial resection of the majority and more, 1 Cases of preoperative diagnosis of ischial tuberosity,