In operation vena saphena magna in 1 case was injured.7 cases felt knee joint pain after operation.

术大隐静脉1例，术后痛7例。

Conclusion Clinical dignosis of traumatic patella metachoresis is based on trauma and knee joint arthrocele and patella metachoresis.

结论外性滑动髌骨诊要注意外、膝部肿胀青紫史，屈膝髌骨向外移位。

For knee joint ache: The focus of the knee joint is on the both side of the knee, pointed out by binger in the following pictures.

六、膝痛患者：膝痛的病灶在膝盖骨的两侧，手指的地方。