The invention relates to the field of orthopaedics medical appliance, especially an external functional 
knee joint fixing rack for early 
knee joint dirigation, which comprises locking pin structure composed of 
steel ball, C-formed tabular clamping 
steel ball rolling mechanism, C-formed tabular clamping 
steel ball slideway, U-formed head wedge steel ball support bar forming steel ball rolling slideway through vertically and horizontally matching, U-shaped rotating wheel comeandgo regulating and stabilizing mechanism, right locking pin mechanism, right adjustable 
arch form rack mechanism, eccentric shaft, left locking pin mechanism, and left adjustable 
arch form rack mechanism. The invention combines functional 
dissection of 
knee joint and 
biomechanics principle, is designed according to the traveling track of the unequal 
semidiameter center point of knee joint center of curvature, and has good stability and safety, good viability and flexibility for performing dirigation. The invention can be used for treating knee joint 
instability caused by ligamentous injury of knee joint, internal lateral 
ligament or ligamentum cruciatum anterius damage common in knee fracture, can effectively control crossrange activity of knee joint and promote 
ligament recovery.