REIDER PART 216

176__Chapter 5_Pelvis, Hip, and Thigh

Figurę 5-19. Normal standing position.

examiner is another way to observe the patient s natural foot placement.

Femoral Version. When in-toeing or out-toeing is observed, additional tests may help the examiner deter-mine whether the abnormality lies in the femur, tibia, or the foot. Rotational malalignment of the femur is usuaily due to yariations in the version of the femoral neck. 'The version of the femoral neck refers to the angle that the femoral neck makes in relation to the coronal piane of the rest of the femur. This coronal piane is usuaily taken to be the piane defined by the posterior aspcct of the two femoral condyles, and it may be estimated from the flex-ion axis of the knee. A normal femoral neck is anteverted about 8° to 15°; that is, it angles forward 8° to 15° from the piane defined by the posterior aspcct of the femoral condyles.

When the femoral neck angles forward morę than this, the patient is said to have increased femoral antever-sion. A patient with increased femoral anteyersion tends to stand with the limb in an internally rotated position, producing in-toeing. If, however, an increased femoral anteyersion is compensated by increased cxternal rotation of the tibia, the patient docs not exhibit in-toeing but rotational malalignment of the knee instead. This is described in Chapter 6, Knee.

If the femoral neck is anglcd less than 8° to 15° ante-rior to the coronal piane of the femur, the patient is said to have decreased femoral anteyersion or femoral retroversion. The patient with decreased femoral anteyersion tends to stand with the limb in an cxternally rotated position, producing out-toeing. Decreased femoral anteyersion is less common than increased femoral anteyersion; it may be found among ballet dancers, who are required to perform with their feet in the turned-out position.

The amount of femoral anteyersion present is most precisely assessed by complex radiographic methods. However, Craig’s test may be used to estimate the amount of femoral anteyersion present. To perform Craig s test, the patient is positioncd prone on the exam-ining tablc, with the ipsilateral knee flexed 90°. The exam-iner palpates the lateral prominence of the greater trochanter with one hand while controlling the rotation of the limb with the other. An imaginary vertical linę serves as the reference for this test. The limb is then rotated until the lateral prominence of the greater trochanter is felt to be maximal (Fig. 5-20). The angle madę betwecn the axis of the tibia and the vertical is con-sidered an approximation of the femoral anteyersion. It normally varies between 8° and 15". This is also known as the Ryder method for measuring femoral anteyersion. Tibial Torsion. Rotational abnormalitics of the tibia may also produce in-toeing or out-toeing. In the normal individual, about 20° of external tibial torsion is present. This means that the axis of the ankle joint is externally rotated about 20° compared with the axis of the knee joint. Uncompcnsated external tibial torsion bcyond this amount favors out-toeing, whereas less external tibial torsion, or actual internal tibial torsion, favors in-toeing. Tibial torsion can also be estimated with the patient lying prone on the examination table, the knees flexed 90°, and the tibias held yertical. The patients ankles are held in a neutral position at right angles to the tibias. In this position, the flexion axis of the knees should be

Figurę 5-20. Craig’s test for measuring femoral anteyersion.