The Back of the Thigh.

The hamstring muscles are thrown into prominence by standing on tiptoes, or by flexing the leg against resistance; at the same time a well-marked furrow indicating the external intermuscular septum of the thigh is seen; behind this furrow is the biceps, and in front of it the vastus externus.

The course of the great sciatic nerve corresponds to the upper half of a line extending from a point midway between the ischial tuberosity and the great trochanter to the middle of the popliteal space; the small sciatic nerve, indicated by the same line, descends superficial to the biceps, while the great sciatic nerve lies under cover of it.

The external popliteal nerve can be felt as it descends immediately behind the tendon of biceps and the head of the fibula.

The internal popliteal nerve and popliteal vessels are indicated by a line drawn from a point a little internal to the upper angle of the popliteal space, to a point midway between the condyle of the femur, and thence down the middle of the space to the level of the lower part of the tubercle of the tibia.

The Front of the Thigh.

Poupart's ligament, in the fold of the groin, divides the front of the thigh from the abdomen. Comparative measurements of the length of the limbs are made from the anterior superior spine of the ilium to either of the malleoli with the pelvis horizontal.

The long saphenous vein is indicated by a line drawn from the adductor tubercle of the femur to the lower part of the saphenous opening (1 1/2 inches below and external to the pubic spine).

The course of the femoral artery is mapped out, with the thigh slightly flexed and rotated outwards, by a line drawn from a point midway between the anterior superior spine and the symphysis pubis, to the adductor tubercle of the femur; the upper third of this line corresponds to the part of the artery in Scarpa's triangle, and the middle third to that in Hunter's canal.

The Knee.

The patella can be easily outlined and moved from side to side with the knee extended and the quadriceps relaxed; with the quadriceps contracted the patellar ligament can be traced to its insertion. In semiflexion, the inner margin of the internal condyle, the upper border of the inner tuberosity of the tibia, and the lower part of the patella, are distinctly visible, and together bound a triangular depression which overlies the line of the joint and the anterior part of the internal semilunar cartilage.

The Leg.

The inner surface of the tibia is subcutaneous throughout.

The shaft of the fibula, somewhat posterior to the tibia, is only subcutaneous just above the malleolus.

The extensor and peroneal muscles, when thrown into action, are mapped out on the surface by grooves corresponding to the intermuscular septa.

The cutaneous part of the musculo-cutaneous nerve corresponds to the lower half of a line drawn from the anterior border of the head of the fibula to the anterior border of the external malleolus.

The anterior tibial artery enters the leg two inches below the tubercle of the tibia; in the upper two-thirds of its course it lies on the interosseous membrane; in its lower third it lies on the front of the tibia and terminates in front of the ankle-joint midway between the two malleoli.

The short saphenous vein, which lies a little to the outer side of the tendo Achillis, gradually reaches the middle of the calf and ascends to the popliteal space. The internal saphenous vein and nerve lie along the inner border of the tibia.

The course of the posterior tibial artery is indicated by a line drawn from the lower angle of the popliteal space to a point midway between the internal malleolus and the tendo Achillis. The peroneal artery, beginning three inches below the head of the fibula, is indicated by a line from that point to one midway between the external malleolus and the tendo Achillis.