Surgical assemblies which reduce stress on a patient lower extremity while facilitating surgical procedures are disclosed. A surgical table extension is disclosed for positioning lower extremities. The table extension comprises a limb manipulator, a base, a platform support, and a perineal post. In another aspect, a surgical table extension comprises a brace assembly which contacts a patient foot, ankle, lower leg, and thigh. The brace assembly is connected to a limb manipulator, enabling the lower extremity to be rotated and manipulated. Rotation forces are applied to both the foot and the thigh, reducing stress on the patient knee.