will be all right. Dislocation of the knee is rare, though it may occur in any direction. Often the bursæ of the joint are irritated, as by kneeling to scrub floors, and bursitis or housemaid's knee results. Fracture of the patella may be caused by muscular traction or by direct violence, and is generally repaired by making an incision and sewing the parts of the bone together. Tumor albus or white swelling is tuberculosis of the knee and is fairly common in children. Specific knee means syphilis of the knee and generally occurs in both knees.
The Tibia.—The tibia or shin bone is next longest to the femur and is on the inner side of the leg, corresponding to the ulna in the arm. The shaft is prismoid and is more slender for the lower quarter, where fracture is consequently most frequent. The anterior border forms the crest or shin and can be felt for its upper two-thirds. The lower extremity, which is smaller than the upper, articulates with the astragalus bone of the ankle and with the fibula. Its head or upper extremity is expanded into two lateral tuberositis for articulation with the femur and for muscular attachment, both of which can easily be felt just below the bend of the knee. Their upper surfaces are smooth and concave, with a vertical bifid spine in the middle and a prominent tubercle for the attachment of the semilunar cartilages on either side. On the anterior surface of the head, below, is a rough eminence or tubercle, which also can be felt. The lower part of this is for the attachment of the ligamentum patellæ, while the upper part, which is smoother, is for the bursa that is placed under the tendon to prevent friction. On the back of the outer tuberosity is a facet for the head of the fibula. At the lower end there projects downward on the inner side, overhanging the arch of the foot, the internal malleolus, the prominent part of the ankle. It is on a higher level and somewhat farther forward than the external malleolus.
The Fibula.—The fibula is the most slender of all the bones in proportion to its length and is on the outer side
