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Lateral View of Hip

This view demonstrates the femoral neck and the relationship of the femoral head to the acetabulum. Fractures of the femoral neck can again be visualized on this film and, in particular, the degree of angulation can be assessed. Dislocations around the hip are not infrequent in road traffic accidents. In most cases, the displacement is posterior due to the impact a patient receives whilst in the sitting position. Dislocations in an anterior direction are much less common. Associated fracture dislocations must be checked for.

Antero-posterior View of Hip

Shenton's line is formed from the continuity of the inferior aspect of the femoral neck through to the inferior aspect of the superior pubic ramus. This gives a good guide to the normal relationship of the head of the femur to the pelvis. Synovial membrane is very extensive around the hip joint and, like the capsule, comes well down the femoral neck, especially anteriorly. Note the normal pattern of the bone trabeculae in the femoral neck, indicating the lines of stress. Fractures of the femoral neck are common, especially in the old, and as they may be impacted they are sometimes difficult to visualize. If severe separation of the femoral head occurs, then the possibility of avascular necrosis exists and it must therefore be checked on follow-up films.

Antero-posterior View of Pelvis

The bones and soft tissues of the pelvis should be studied in this view. Fractures and dislocations occurring in the pelvic bones are particularly important in relation to their effects on the pelvic contents. As with any fixed bony ring, fractures and dislocations must be checked to make sure there is no further breach of the ring, as commonly occurs. Ramus fractures of the obturator ring are often multiple because of this. Look for dislocation of the femoral head in relation to the acetabular fossa and check the relationship of the sacro-iliac joint. If there is suspected instability of the pubic symphysis, as occurs in professional sportsmen, particularly footballers, then films should be taken with the patient standing on one leg and then the other to see if there is any movement of the joint.

Antero-posterior View of Plain Abdomen

This is a supine view to show the general layout of abdominal viscera. Note the slightly lower position of the right kidney compared to the left, due to the liver mass. Note the position of the spleen and liver edge. Note also the normal gas shadow in the antrum of the stomach. When considering abdominal films in patients with abdominal pathology, it is often essential to have an erect film in addition to the one shown. These two films are complementary in showing abnormalities. Look for bowel gas patterns, renal and gall bladder calculi, the psoas outlines, the normality of the bone structure, and check also the hernial orifices.

Left Lateral View of Chest

The projection demonstrates mediastinal divisions into the superior, anterior, middle and posterior. Note the backwards slant of the trachea from the thoracic inlet to the carina. This slant should be borne in mind when tracheal tomograms are performed. Note the position of the outflow tract of the right ventricle and the high position of the left atrium. Note the position of the lung fissures, the left oblique fissure reaching its inferior limit about 5 cm behind the sternum. The right oblique fissure travels more anteriorly at its lower limit. Note also the apparently translucent anterior mediastinum in the normal.

Postero-anterior View of Chest

This is the commonest radiogram taken and thus it is important that the normal anatomy is known thoroughly. As with any x-ray, a system must be devised so that all the film is looked at in turn. However, certain hidden areas on a chest film warrant special attention and these include: behind the first ribs, behind the heart shadow, the posterior costophrenic angles which are obliterated on this view by the diaphragmatic shadows, and the hilar regions. Note the air in the trachea and main extra-pulmonary bronchi. Note that the hilar shadows are composed only of vessels and the normal intra-pulmonary bronchi cannot be visualized. The right heart border is formed from the superior vena cava, right atrium and inferior vena cava. The left heart border is formed from the aortic knuckle, the pulmonary conus, the left atrial appendage and the left ventricle.

Hand and wrist X-ray examination

Fractures and dislocations are particularly important in the wrist, as considerable incapacitation with osteoarthritis can result from delayed treatment. Note that fractures of the scaphoid may not show for 10 days following the injury. If a fracture of the waist of the scaphoid is mistreated, ischaemic necrosis of the distal fragment may result. It is important to learn the normal appearance of the positions of the carpal bones so that dislocations are not overlooked. Common fracture sites include the following: fracture of the distal radius and ulna with backward displacement (Colles' fracture); forward displacement of this fracture may occur which is relatively rare (Smith's fracture); fracture of the base of the first metacarpal (Bennett's fracture). Spiral fractures of the metacarpals and distal shaft fractures of the fourth and fifth metacarpal bones may follow a punch! Note that many systemic diseases have bony and soft tissue abnormalities which can be seen on a hand x-ray, e.g. hyperparathyroidism, scleroderma and rheumatoid arthritis.

Superoinferior View of Shoulder (Axial with Abduction)

This projection shows the position of the head of the humerus in relation to the glenoid cavity. It also shows, on this normal x-ray, that there is no dislocation. In patients with suspected dislocation, this x-ray may not be possible to obtain and a lateral shoot-through is a further method of evaluating displacement. Fractures of the coracoid process and acromion, although uncommon, can be visualized on this film. Fracture of the greater tuberosity, which may be missed on the antero-posterior projection, can again be seen.

Antero-posterior View of Shoulder

The middle and outer parts of the clavicle are well seen and are common fracture sites. Check the acromio-clavicular joint to see if there is any subluxation or dislocation present. This should be confirmed by a weight-bearing view if suspected. 

Look for fractures and dislocations of the humeral head. Both anterior and posterior dislocations can be missed on this view unless another radiogram at a different angle is performed. Look for supraspinatus tendon calcification. Look for deformities of the rotator cuff, evidence of recurrent dislocation or occasional congenital foramina of the scapula.

Lateral Soft Tissue Film of the Face

The soft tissue projection of the face is mainly taken for nasal spine and nasal bone fractures; however, nasal fracture displacement is best visualized on an axial projection. This soft tissue view is also useful for assessment of dental occlusion or bite.

Lateral Soft Tissue Film of the Neck

This film uses the natural air of the pharynx and larynx as contrast medium. The cartilages of the larynx are seen and undergo true ossification rather than calcification. The retropharyngeal space between the posterior wall of the trachea and the anterior border of the cervical spine should not exceed the AP diameter of one vertebral body. Note the following: the articulation of the thyroid and cricoid cartilages; the air in the ventricle of the larynx between the true and false cords; and the position of the larynx extending from C3 to C6. The pharynx can also be seen in its anatomical divisions of nasopharynx, above the soft palate, oropharynx between soft palate and base of tongue, and hypopharynx from base of tongue inferiorly.

Antero-posterior and Lateral Views of Elbow

Effusions into the elbow joint are commonly associated with undisplaced fractures of the radial head due to trauma. These radial head fractures may be difficult to see unless full projections are taken. The anterior and posterior fat pads are a particularly useful guide in assessing an effusion, as both will be elevated from their resting position against the distal end of the humerus. The two views are again needed in trauma cases to show any dislocation with or without associated fractures. A supracondylar fracture in children is particularly important because of the risk of a Volkmann's contracture due to ischaemic fibrosis. 

When the forearm bones are x-rayed for trauma, it is essential to have views of the joints at either end. This applies to any long bone examination. Fractures of the forearm bones are often paired, and if single fractures with displacement occur, then either wrist or elbow dislocation of the other bone must be looked for. Examples of this are fracture of the ulna with forward dislocation of the radial head (Monteggia) and fracture of the radial shaft with distal radio-ulnar dislocation (Galeazzi).

Tomograms of the Internal Ear

These tomograms demonstrate the anatomy more clearly than the plain films, and are essential when looking for small lesions such as fractures and congenital anomalies of the middle ear and temporal bone. High-quality tomography often of polycycloidal type together with 1 or 2 mm cuts are needed to show these minute structures. The crista transversalis separates the facial from the acoustic nerve and is an important landmark, as it disappears in intracanalicular acoustic neuromata.

Occipito-mental and Occipito-frontal Views of Skull

These two projections show the frontal and maxillary sinuses to their best advantage. The maxillary antrum is seen on the occipito-mental view; in particular, the roof of the antrum, the floor of the orbit, is clearly visualized. The frontal sinus is seen on both views. Look for sinus abnormalities such as mucosal thickening and fluid levels. Also check for facial fractures. The infra-orbital foramen and the foramen rotundum can be seen on these projections.

Submento-vertical View of Skull

This projection is of the base of the skull. The sphenoid air sinus is well shown. The numerous exit foramina from the skull are easily identified. Look for enlargement of the foramen spinosum which can occur in vascular vault meningiomas with a large external carotid arterial supply. Check the petrous apex and the region of the jugular foramen. Check the middle ear and its ossicles. Identify the three bony lines which overlap anteriorly: the greater wing of the sphenoid, the posterior wall of the orbit and the posterior wall of the maxillary antrum.

30° Fronto-occipital View of Skull (Towne's Projection)

This view shows the region of the foramen magnum, the occipital bone and the petrous ridges, which should be checked for any abnormality. 

Check for posterior vault fractures. See if the pineal or the choroid plexuses of the lateral ventricles are calcified and, if they are, check there is no midline shift. This view also demonstrates the zygomatic arch clearly.

Lateral View of Skull

This is probably the most important of the skull views. There are several features which must be checked on this projection: the hypophyseal fossa, both for pituitary tumours and for the effects of raised intracranial pressure; the position of the pineal, if calcified; the width of the soft tissue shadow on the posterior aspect of the nasopharynx and oropharynx, and the posterior walls of the maxillary antra.

Do not confuse vault fractures with vascular markings and suture lines. Look for other physiological calcification sites, e.g. habenular calcification (reverse C-shape), petroclinoid and interclinoid ligament calcification. The frontal, sphenoid and maxillary air sinuses are clearly visualized on this projection, as is the pterygopalatine fossa.

Occipito-frontal View of Skull

This projection allows the orbits to be checked for their equality of size, which is important in patients with proptosis. The floor of the hypophyseal fossa can be seen through the nasal cavity and this should be looked at closely if a pituitary tumour is suspected. Check the supraorbital fissure and the greater and lesser wings of sphenoid for any abnormality. Watch for vault fractures in the frontal region and for blowout fractures through the floor of the orbit. The nasal cavity, the medial wall of the maxillary antrum and the ethmoid air cells are well seen in this projection.