Plain Imaging

Fig. 6.1

True-ap view of a right shoulder joint. Normal findings (Reprinted with permission from Lehrbuch der röntgendiagnostischen Einstelltechnik, 6th edition, 2008)

Axial View

Usually the axial view is performed with the patient laying onto the x-ray table with his body axis in parallel to the table, but may also be performed with the patient sitting next to the table. The affected side is abducted to an angle between 60° and 90° and stuffed so that the shoulder joint is positioned in the center of the x-ray film (see Fig. 6.2). The x-ray tube is in a 90° position with cranio-caudal central ray being focused on to the humeral head almost parallel to the body axis (see Fig. 6.3). This view allows for an undistorted view of the coracoid process and the acromio-clavicular joint being projected onto the upper arm. A well adjusted radiograph shows the humeral head and glenoid clearly arranged and without any severe overlap. The shoulder joint region is virtually seen bottom-up like.

Fig. 6.2

Axial view of a right shoulder joint. Normal findings (Reprinted with permission from Lehrbuch der röntgendiagnostischen Einstelltechnik, 6th edition, 2008)

Fig. 6.3

Scapular y-view of a right sighted shoulder joint. Normal findings (Reprinted with permission from Lehrbuch der röntgendiagnostischen Einstelltechnik, 6th edition, 2008)

Alternative: Velpeau View

As alternative to the axial view the technique according to Velpeau should be mentioned. This technique offers in comparison to the axial view the advantage that the affected side does not necessarily need to be taken out of the sling [7]. For this x-ray technique the patient is sitting with his back opposite to the x-ray table leaning backwards for approximately 30°. The central ray hits the center of the shoulder joint running perpendicular to the x-ray film. This radiographic view presents the gleno-humeral joint in an augmented way with the humeral shaft appearing shortened and thus the relation between the humeral head and the glenoid is well evaluatable. However, several bony overprojections might be present so that in general the axial view should preferably be performed.

Lateral View (y-View, Transscapular View)

The patient is standing sideways to the stand with the affected side bearing on with both arms hanging down. The healthy side is tilted ventrally for approximately 45° so that the plain scapular bone is positioned perpendicular to the x-ray film (see Fig. 6.3). The x-ray beam is focussed vertically running latero-medial through the scapula.

In case of a dislocated shoulder joint this radiograph can be performed additionally to the (true) a-p view without any problems since the axial projection is often not possible due to pain. The scapula is pictured as the long bracket of a “y” whereas the short bracket on the ventral side is the coracoid process and on the dorsal side the spina scapulae without overprojection of the ribs. The humeral head is projected onto the glenoid. In case of a dislocation the joint socket looks “empty”.

Trauma Series (True a-p, y-View, Axial-View)

In case a fracture of the proximal humerus is clinically suspected the so-called trauma series consisting of three radiographs as follows:

(a)

(true) a-p view

(b)

y-view

(c)

axial view [8] should be performed (Table 6.1).

Table 6.1

Overview of indications for radiographical examinations of the shoulder joint and proximal humerus respectively

Indication	Choice of x-ray projection
Basic Trauma diagnostics	Shoulder joint in 2 planes:
	1. a-p view in neutral position (standard view)
	2. Axial view
Subcapital humeral fracture	1. a-p view in neutral position (standard view)
	2. Transcapular view
Anterior/posterior dislocation	1. a-p view in neutral position (standard view)
Control after repositioning	2. Transscapular view
Fracture of greater tuberosity	1. a-p view in neutral position (standard view)
Often associated with subcapital humeral fracture	2. a-p view in internal rotation
or dislocation of the shoulder	3. a-p view in external rotation
Minor tuberosity fracture	1. a-p view in neutral position (standard view)
	2. Axial view