Patient: 2-month old female infant
Sites of injection: PCV and Penta - Anterolateral thigh, and OPV - Oral
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: All four heads extend leg at knee joint; rectus femoris muscle acting alone also flexes thigh at hip joint.
How to locate: Divide thigh into three equal parts. The middle part is the ideal location. Palpate for bones and avoid.
Patient: 65 year old grandfather
Preferred site for IM injection: Deltoid muscle
Origin: Acromial extremity of clavicle (anterior fibers), acromion of scapula (lateral fibers), and spine of scapula (posterior fibers)
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: Measure 2-3 finger widths below the shoulder bone and 2-3 finger widths above upper arm bone. Injection site is in the middle.
Reference: Tortora, G. J., & Derrickson, B. (2017). Principles of anatomy & physiology. Fifteenth edition; Wiley Loose-Leaf Print Companion. Hoboken, New Jersey, John Wiley & Sons, Inc.