1.
Site: Anterolateral thigh
Muscle targeted: Vastus lateralis
Origin: Greater trochanter and linea aspera of femur
Insertion: Patella via quadriceps tendon and then tuberosity via patellar ligament
Action: Extend leg at knee joint
How to locate: Position the patient lying down or being held by a parent. Palpate the muscle below the greater trochanter and above the lateral femoral condyle (knee joint). Divide the muscle into thirds and administer the injection into the middle third of the muscle, in the outer anterolateral aspect, lateral to the midpoint of the thigh.
2.
Site: Upper arm
Muscle Targeted: Deltoid Muscle
Origin: Acromial extremity of a clavicle, acromion of scapula, and spine of scapula
Insertion: Deltoid tuberosity of humerus
Action: Lateral fibers abduct arm at shoulder joint; anterior fibers flex and medially rotate arm at shoulder joint; posterior fibers extend and laterally rotate arm at shoulder joint
How to locate: Approximately 2–3 fingerbreadths (approximately 2 inches) below the acromion process, and sitting just above the level of the armpit, in the central part of the upper arm.