_Surgical Anatomy_--FRACTURE OF LOWER END OF FEMUR: _Supra-condylar_; _T- or Y-shaped_; _Separation of epiphysis_; _Either condyle_--FRACTURE OF UPPER END OF TIBIA: _Of head_; _Separation of epiphysis_; _Avulsion of tubercle_--DISLOCATIONS OF KNEE: _Dislocations of superior tibio-fibular joint_--INTERNAL DERANGEMENTS OF KNEE--INJURIES OF PATELLA: _Fractures_; _Dislocations_--INJURIES OF LEG: _Fracture of both bones_; _Fracture of tibia alone_; _Fracture of fibula alone_. INJURIES IN THE REGION OF THE KNEE These include the supra-condylar fracture of the femur, the T- or Y-shaped fracture opening into the joint, separation of the lower femoral epiphysis; fracture of the head of the tibia, and separation of its upper epiphysis; the various sprains and dislocations of the knee, as well as its internal derangements; and fractures and dislocations of the patella. #Surgical Anatomy.#--Of the two epicondyles the medial is the more prominent and palpable. The adductor tubercle, which is situated on the upper and back part of the medial epicondyle, gives attachment to the round tendon of the adductor magnus, and marks the level of the epiphysial line and of the upper limit of the trochlear surface of the femur. Between the medial condyle of the femur and the medial condyle (tuberosity) of the tibia, when the limb is in the flexed position, the line of the joint can be recognised as a groove or cleft, and this is made use of in measuring the length of the tibia. The lateral condyle (tuberosity) of the tibia can also be palpated, and must not be mistaken for the head of the fibula, which lies farther back and at a slightly lower level, and can readily be identified by tracing to it the tendon of the biceps. The tuberosity of the tibia, into which the quadriceps extensor tendon is inserted, lies on the same level as the head of the fibula. In the extended position of the limb, the patella is loose and movable on the front of the trochlear surface of the femur, while in the flexed position it sinks between the condyles, resting chiefly on the lateral one and becoming fixed. The popliteal artery and vein and the tibial (internal popliteal) nerve lie in close relation to the posterior aspect of the joint; and the common peroneal (external popliteal) nerve passes behind and to the medial side of the biceps tendon.