but, in making use of this term, remember that the shape it presents is that of an inverted A.

The pubo-femoral band (ligamentum pubocapsulare) is the name applied to several fasciculi of no great strength, which spring from the pubic bone and the thyroid membrane, and join the lower and anterior aspect of the capsule. In cases where the bursa under the ilio-psoas is continuous with the synovial membrane of the joint, the aperture of communication is placed between this band and the ilio-femoral band.

The ischio-capsular band (ligamentum ischio capsulare) is stronger. It takes origin from the ischium below the acetabulum, and passes into the lower and posterior aspect of the capsule.

The zonular band (zona orbicularis) is composed of circular fibres, and will be observed on the posterior aspect of the capsule. It encircles the neck of the femur behind and below, but is lost as it is traced forwards towards the upper part and the front of the capsule.

The dissector has already observed the close connection which is exhibited between the capsule of the hip-joint and the tendons of the gluteus minimus, and the reflected head of the rectus. Reinforcing fibres are contributed to the capsule by both of these tendons.

Movements permitted at the Hip-joint.-Before the capsule of the joint is opened the range of movement which is permitted at the hipjoint should be tested. Flexion, or forward movement, is very free, and is only checked by the anterior surface of the thigh coming into contact with the abdominal wall. Extension, or backward movement, is limited by the ilio-femoral band. This powerful ligament has a most important part to play in preserving the upright attitude with the least possible expenditure of muscular exertion. In the erect posture the line of gravity falls slightly behind the line joining the central points of the two hip-joints. In this position the ilio-femoral bands are tight, and prevent the pelvis from rolling backwards on the heads of the femora. Abduction, or outward movement of the thigh, is checked by the pubo-femoral band. Adduction, or inward movement (e.g., as in crossing one thigh over the other), is limited by the upper portion of the ilio-femoral band and the upper part of the capsule. Rotation inwards tightens the ischio-capsular band, and is therefore in a measure

restrained by it. Rotation outwards is limited by the outer portion of the ilio-femoral band. In circumduction, which is combination of the movements of flexion, abduction, extension, and adduction, different parts of the capsular ligament are tightened at different stages of the

movement.

The flexor muscles, which operate on the femur at the hip-joint, are chiefly (1) the ilio-psoas, and (2) the pectineus; the extensors are-(1) the gluteus maximus, and (2) the gluteus medius; the abductors(1) the upper part of the gluteus maximus, (2) the gluteus medius, (3) the gluteus minimus; the adductors—(1) the three adductors, (2) the pectineus, (3) the lower part of the gluteus maximus, and (4) the obturator externus; the inward rotators—(1) the anterior part of the gluteus medius, (2) the anterior part of the gluteus minimus, (3) the tensor fascia femoris, and (4) the ilio-psoas; the outward rotators—(1) the two obturator muscles, (2) the gemelli, (3) the pyriformis, (4) the quadratus femoris, and (5) the gluteus maximus.

Dissection. The hip-joint may now be opened, and in doing this it is advisable to remove in the first instance the whole capsule, with the exception of the ilio-femoral band. The enormous strength of this portion of the capsule can in this way be appreciated. It is fully a quarter of an inch thick, and a strain varying from 250 lbs. to 750 lbs. is required for its rupture (Bigelow). It is very rarely torn asunder in dislocations, and consequently the surgeon is enabled in most cases to reduce the displacement by manipulation. The ilio-femoral band may now be removed.

The Cotyloid Ligament (labrum glenoidale) is a firm fibro-cartilaginous ring, which is fixed to the brim or margin of the acetabulum. It bridges across the notch, and thus completes the circumference of the cavity, deepens it, and at the same time narrows slightly its mouth. The cotyloid ligament fits closely upon the head of the femur, and acting like a sucker, exercises an important influence in retaining it in place. Both surfaces are covered by synovial membrane; its free margin is thin, but it is much thicker at its attachment to the acetabular brim.

The Transverse Ligament (ligamentum transversum acetabuli) is composed of some transverse fibres which bridge across the notch in the inferior part of the acetabulum, and are attached to its margins. The more superficial of these fibres are more or less directly connected with the deep surface of the cotyloid ligament as it

stretches across the notch, but they do not fill up the entire gap; a narrow interval is left between the transverse ligament and the bone for the entrance of blood-vessels and nerves into the joint.

The Ligamentum Teres (ligamentum teres femoris) is not round, as its name might lead one to expect, but somewhat flattened and triangular in shape. Its narrow femoral extremity is implanted into the upper margin of the pit which marks the head of the femur, whilst its flattened acetabular end is bifid, and is fixed to the margins of the notch in the lower part of the acetabulum, and also to the transverse ligament. This attachment can be defined by removing the synovial membrane and some areolar tissue. The ligamentum teres is completely surrounded by synovial membrane, and a small artery runs along it to the head of the femur. It is difficult to understand the part which the ligamentum teres plays in the mechanism of the hip-joint. It presents very different degrees of strength in different individuals. It becomes very tense when the thigh is slightly flexed and then adducted.

Synovial Membrane and Interior of the Joint.-A mass of soft fat occupies the non-articular bottom of the acetabular cavity. Upon this the ligamentum teres is placed, and blood-vessels and nerves enter it by passing through the notch under cover of the transverse ligament. The vessels come from the internal circumflex and the obturator arteries, and the nerves come from the anterior division of the obturator nerve and from the accessory obturator, when it is present. A nerve-twig is also supplied to the back of the joint by the nerve to the quadratus femoris.

The synovial membrane lines the interior of the capsule. From this it is reflected on to the neck of the femur, and it clothes the bone as far as the margin of the articular cartilage which covers the head. Along the line of reflection some fibres of the capsular ligament proceed upwards on the neck of the femur and raise the synovial

membrane in the form of ridges. These fibres are termed the retinacula or cervical ligaments.

These ligaments are of some surgical importance. In intracapsular fracture of the neck of the femur they may escape rupture, and they may then to some extent help to retain the fragments in apposition. Hence examinations of this class of fracture must be conducted gently, lest by rupturing this ligamentous connection, the fragments be permanently displaced.

At the acetabular attachment of the capsular ligament the synovial membrane is reflected on to the cotyloid ligament and invests both its surfaces. It also covers the articular surface of the transverse ligament and the cushion of fat which occupies the bottom of the cavity. Lastly, it gives a tubular investment to the ligamentum teres.

Removal of the Limb.-The limb may now be removed from the trunk by dividing the ligamentum teres. It should then be taken to one of the tables set aside for the dissection of separate parts. Before proceeding to the dissection of the leg it is advisable to study the attachments of the various muscles to the femur. The bulk of these may be removed, but a small portion of each should be left, so that their connections may again be revised, should it be found necessary to do so at a later period.

THE LEG.

Surface Anatomy.-The relation of the tibia and fibula to the surface should be carefully investigated. The sharp anterior border of the tibia or shin does not form a projection visible to the eye, but nevertheless it is subcutaneous, and can be very distinctly felt when the finger is passed along it. It pursues a slightly sinuous course, and in its lower part becomes rounded-off and indistinct. The broad flat internal surface of the shaft of the tibia is also subcutaneous below the level of the insertion of the sartorius, and the inner border of the bone can be followed by the finger very readily throughout its entire length. The fibula is more deeply placed, and the upper

half of its shaft cannot be felt from the surface owing to the manner in which it is surrounded by muscles. The head of the bone, however, is very evident where it articulates with the outer and back part of the tuberosity of the tibia and for a short distance above the external malleolus the shaft of the fibula is subcutaneous over a triangular area which is interposed between the peroneus tertius muscle in front and the peroneus longus and peroneus brevis muscles behind.

The two malleoli form marked projections in the region of the ankle. The internal malleolus is the oroader and more prominent of the two; it does not descend so low down, however, and when viewed from the front it is observed to reach further forwards. This latter appearance is due to its greater breadth, because when examined from behind the posterior borders of the two projections are seen to occupy very nearly the same plane.

On the posterior aspect of the leg the prominence known as the "calf of the leg" is visible. This is largely due to the fleshy bellies of the gastrocnemius muscle. Below the calf and immediately above the heel the powerful tendo Achillis can be felt. In front of this tendon a slight hollow is apparent on either side of the limb.

As the skin is reflected from the dorsum of the foot during the dissection of the leg, the present opportunity should be seized for studying the surface anatomy of the foot. The individual tarsal bones cannot be recognised through the integuments which cover the dorsum of the foot; but if the foot be powerfully extended the head of the astragalus will be brought into view in the shape of a slight prominence. The margins of the foot require very careful study, because it is by the recognition of certain bony projections in these that the surgeon is enabled to determine the point at which to enter the knife when he is called upon to perform partial amputation of the foot. Examine the inner margin first. Begin behind at the projection formed by the internal tuberosity of the os calcis, and proceed forwards. About one inch below the internal