Surface anatomy of thigh.pdf

Surface anatomy of Lower limb (thigh) Skeletal surface landmarks An oblique skin crease, the fold of the groin, marks the junction of the front of the thigh with the anterior abdominal wall It corresponds fairly accurately to the inguinal ligament. The anterior superior spine of the ilium lies at...

Surface anatomy of Lower limb (thigh) Skeletal surface landmarks An oblique skin crease, the fold of the groin, marks the junction of the front of the thigh with the anterior abdominal wall It corresponds fairly accurately to the inguinal ligament. The anterior superior spine of the ilium lies at the lateral end of the fold and can always be palpated. At its medial end, the fold reaches the pubic tubercle Skeletal surface landmarks From the anterior superior spine, the iliac crest is easily palpable along its entire length It terminates posteriorly as the posterior superior iliac spine Loading… This can be felt in the depression seen just above the buttock. This lies at the level of the second segment of the sacrum at the level of the middle of the sacroiliac joint and the level of the termination of the spinal dural sac  Skeletal surface landmarks The ischial tuberosity is palpated in the lower part of the buttock It is covered by the gluteus maximus when the hip joint is extended, but can be identified without difficulty when the hip is flexed, as in the sitting position The ischial tuberosity then emerges from under cover of the lower border of the gluteus maximus and is then subcutaneous separated from the skin only by a pad of fat and the ischial bursa. The weight of the body is supported by the ischial tuberosities in the sitting position.  Skeletal surface landmarks The greater trochanter of the femur lies a hand's breadth inferior to the midpoint of the iliac crest It can be both seen and felt as a prominence in front of the hollow on the side of the hip Loading… indeed, it is the only part of the proximal portion of the femur which is palpable  Skeletal surface landmarks The lower end of the femur is less deeply placed when the knee is flexed passively, the medial surface of the medial condyle and the lateral surface of the lateral condyle of the femur can be palpated, and portions of the femoral articular surface can be examined on each side of the lower part of the patella.  Skeletal surface landmarks The patella can be identified readily and, when the quadriceps is relaxed in the fully extended knee, it can be tilted and moved on the lower end of the femur The lower limit of the patella lies more than 1 cm above the line of the knee joint.  Soft tissues landmarks The femoral artery enters the thigh at the fold of the groin at a point midway between the anterior superior iliac spine and the pubic symphysis Its course can be represented by the upper two-thirds of a line which joins that point to the adductor tubercle when the flexed thigh is abducted slightly and rotated laterally At its origin, the pulsations of the femoral artery can be felt and in this situation the vessel can be compressed against the superior ramus of the pubis.  Soft tissues landmarks The femoral pulse constitutes an important landmark; immediately medial to it is the surface marking of the femoral vein and the termination of the great saphenous vein The course of this vein can be marked out in the thigh by a line passing from this point downwards and backwards to a hand's breadth behind the patella. Soft tissues landmarks Immediately lateral to the femoral pulse is the surface marking of the femoral nerve A finger placed on the femoral pulse and then slid upwards immediately above the groin fold lies on the internal inguinal ring. Pressure at this point will control the descent of a reduced indirect inguinal hernia but not a direct hernia, which passes medial to the inferior epigastric artery.  Soft tissues landmarks The shallow depression which lies immediately below the fold of the groin corresponds to the femoral triangle It is bounded on its lateral side by the strap-like sartorius muscle, which can be both seen and felt in a reasonably Loading… thin and muscular subject when the hip is flexed in the sitting position while keeping the knee extended, especially when the thigh is slightly abducted and rotated laterally The muscle can be traced downwards and medially from the anterior superior spine of the ilium to approximately half-way down the medial side of the thigh. Distally, it may be identified as a soft longitudinal ridge passing towards the posterior part of the medial femoral condyle Soft tissues landmarks The bulky, fleshy mass at the upper part of the medial side of the thigh is formed by the adductor group of muscles The medial border of adductor longs forms the medial boundary of the femoral triangle and can be felt as a distinct ridge when the knee is adducted against resistance At its upper end, its tendon of origin can be identified immediately below the pubis and felt between the finger and thumb. Its origin is immediately below the pubic tubercle and the tendon forms a useful guide to this bony landmark. Soft tissues landmarks The forward convexity of the front of the thigh is caused by the curvature of the femur which is covered by the fleshy mass of the quadriceps femoris. Three of its four components can be identified: rectus femoris may be seen as a ridge passing down the anterior aspect of the thigh when the sitting subject flexes the hip with the knee extended vastus medialis constitutes the bulge above and medial to the patella vastus lateralis forms the elevation above and lateral to the patella, more proximal and less pronounced than that of vastus medialis. Soft tissues landmarks The fourth component, vastus intermedius, is hidden by the other three muscles. The flattened appearance of the lateral aspect of the thigh is produced by the iliotibial tract, the thickened portion of the deep fascia of the thigh, or fascia lata, which stands out as a strong, visible groove on the anterolateral aspect of the knee when the leg is extended against gravity. The tract extends from its origin on the iliac crest to its insertion at the upper end of the tibia.  Soft tissues landmarks The bulky prominence of the buttock is caused by three factors: the forward tilt of the pelvis, which throws the ischium backwards the size of gluteus maximus the large amount of subcutaneous fat. Soft tissues landmarks The horizontal gluteal fold marks the upper limit of the posterior aspect of the thigh; it does not correspond to the lower border of the gluteus maximus, but is caused by fibrous connections between the skin and the deep fascia. The natal cleft, which separates the buttocks inferiorly, commences above at the third or fourth sacral spine Soft tissues landmarks The upper border of gluteus maximus commences on the iliac crest about 3 cm lateral to the posterior superior spine and runs downwards and laterally to the apex of the greater trochanter. Its lower border corresponds to a line drawn from the ischial tuberosity, through the midpoint of the gluteal fold, to a point about. Although this muscle overlaps the ischial tuberosity in the standing position, on sitting, the muscle slides superiorly posterior to the tuberosity leaving it free to weight-bear. The muscle can be felt to contract when the hip is extended against resistance. Soft tissues landmarks Gluteus medius completely covers the underlying gluteus minimus. They lie in the slight depression superolateral to gluteus maximus and inferior to the anterior portion of the iliac crest. Soft tissues landmarks Gluteus medius and minimus constitute the major abductors of the hip and are demonstrated by asking the subject to stand on one limb The ipsilateral muscles contract and tilt the pelvis in order to stabilize the centre of gravity. In this action, the contralateral gluteal fold will rise. If the hip abductors are paralysed, in congenital dislocation of the hip or in a long-standing fracture of the neck of the femur, this mechanism is disturbed and the normal tilting of the pelvis does not occur. Indeed, when the patient stands on the affected hip, the pelvis tilts downwards on the contralateral side (Trendelenburg's sign).  Soft tissues landmarks The surface markings of the sciatic nerve can be represented by a line which commences at a point midway between the posterior superior iliac spine and ischial tuberosity, which curves outwards and downwards through a point midway between the greater trochanter and the ischial tuberosity and then continues vertically downwards in the midline of the posterior aspect of the thigh to the upper angle of the popliteal fossa. Here it divides into the tibial and common peroneal nerves, if it has not already done so at a higher level.