- For a 2-month-old infant, the recommended sites of injection are the thighs. The muscle targeted here is the vastus lateralis. Its origin is the greater trochanter and linea aspera of the femur, its insertion is the patella via the quadriceps tendon and then the tibial tuberosity via the patellar ligament, and its innervation is the femoral nerve. Moreover, the area can be located at the anterior lateral aspect of the thigh.
- For a 65-year-old adult, the preferred site for the IM injection is the deltoid muscle of the shoulder. Its origin is the acromial extremity of the clavicle, the acromion of the scapula, and the spine of the scapula. Its insertion is the deltoid tuberosity of the humerus, and its innervation is the axillary nerve. More so, the area can be located on the uppermost part of the arm and the top of the shoulder.