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Chapter 8
The lower limb
THE BONES OF THE LOWER LIMB CHAPTER CONTENTS
The The The The The
bones 273 joints 280 muscles 299 arteries 302 veins 305
The femur (Fig. 8.1; see Fig. 6.1) The femur is the longest and the strongest bone of the body. It has a head, neck, shaft and an expanded lower end. The head is more than half of a sphere and is directed upwards, medially and forwards. It is intra-articular and covered with cartilage apart from a central pit called the fovea, where the ligamentum teres is attached. The blood supply of the femoral head is derived from three sources as follows: • Vessels in the cancellous bone from the shaft; • Vessels in the capsule of the hip joint, which reach the head in synovial folds along the neck; • Negligible supply via the fovea from vessels in the ligamentum teres. The neck of the femur is about 5 cm long and forms an angle of 127° with the shaft. It is also anteverted, that is, it is directed anteriorly at an angle of about 10° with the sagittal plane. Its junction with the shaft is marked superiorly by the greater trochanter and inferiorly and slightly posteriorly by the lesser trochanter. Between these anteriorly is a ridge called the intertrochanteric line, and posteriorly a more prominent intertrochanteric crest. The capsule of the hip joint is attached to the intertrochanteric line anteriorly but at the junction of the medial two-thirds and the lateral third of the neck posteriorly. The shaft of the femur is inclined medially so that whereas the heads of the femurs are separated by the pelvis, the lower ends at the knees almost touch. It also has a forward convexity. The shaft is cylindrical with a prominent ridge posteriorly, the linea aspera. This ridge splits inferiorly into medial and lateral supracondylar lines, with the popliteal surface between them. The medial supracondylar line ends in the adductor tubercle. The lower end of the femur is expanded into two prominent condyles united anteriorly as the patellar surface, but separated posteriorly by a deep intercondylar notch.
