1.
Sites of Injection: Anterolateral thigh
Muscle Targeted: Vastus lateralis
Origin: Greater trochanter and linea aspera of femur
Insertion: Patella via quadriceps tendon and then tibial tuberosity via patellar ligament
Action: Extend leg at knee joint
How to Locate: Place the infant either lying down or held by a parent with their leg relaxed. Locate the greater trochanter and above the lateral femoral condyle (knee joint). Determine the middle third of the muscle, palpate it, and administer the vaccine.
2.
Sites of Injection: Deltoid
Origin: Acromial extremity of clavicle, acromion of scapula, and spine of scapula
Insertion: Deltoid tuberosity of the humerus
Action: Lateral fibers abduct the arm at the shoulder joint; anterior fibers flex and medially rotate the arm at the shoulder joint; posterior fibers extend and laterally rotate the arm at the shoulder joint
How to Locate: Make sure that the patient sits comfortably with their arm exposed at their side. Locate the acromion (the outer edge of the scapula) and visualize an inverted triangle below the shoulder. Administer the injection 3-5 cm below the acromion, in the center of this triangle.