Deltoid tuberosity

The deltoid muscle can be used for i.m. injections in older children, but it is not an option for young infants and children because of their limited muscle mass. Although there are few complications associated with this administration route, nerve injury can occur. The technique is shown in Fig. The area for deltoid administration should be fully visible so that the anatomical landmarks can be visualized. Then the needle for deltoid injection should enter the muscle halfway between the acromium process and the deltoid tuberosity to avoid hitting the underlying nerves. The drug volume that can be administered by this route to older children and adults is 0.1-2ml.The recommended needle length for older children is 1 in. (2.5 cm). 

The triangular deltoid ligament is located medially and is attached above to the medial malleolus and below to the tuberosity of the navicular, the sustentaculum tali of the calcaneus, and the medial tubercle of the talus. The deltoid ligament is so strong that trauma often causes fractures of its bony attachments rather than rupture of the ligament itself. 

Fig. 6.27a,b. Normal subscapularis tendon, a Transverse 12-5 MHz US image over the long axis of the subscapularis tendon (arrowheads). This tendon lies deep to the anterior deltoid muscle and just superficial to the humeral head. It has a convex shape and a well-defined fibrillar echotexture. Note the relatively small area (dashed line) of the lesser tuberosity (LT) on which the tendon inserts, b Schematic drawing of a coronal view through the anterior shoulder illustrates the examination technique. Due to the tendon s broad insertion, the transducer should be swept (arrows) up and down to cover its full width. The insert at the upper left side of the figure indicates probe positioning... 

While tears of the infraspinatus tendon are almost invariably associated with rupture of the supraspinatus, subscapularis ruptures can also be encountered as an isolated problem. Subscapularis tendon tears are mainly related to acute traumatic lesions produced with the arm abducted and in external rotation. Similar to other rotator cuff tendons, complete tears of the subscapularis are revealed by the absence of tendon fibers and the concavity of the deltoid over the naked anterior surface of the humeral head. Incomplete tears of the subscapularis tendon often involve the cranial and preserve the caudal portion of the tendon (Fig. 6.90). This pattern should not be mistaken for complete tears. For this purpose, the morphology of the lesser tuberosity as seen on sagittal planes may help to establish the caudal limit of the tendon and avoid any confusion... 

---