The dorsogluteal site refers to a specific area within the buttocks, primarily used for intramuscular injections. This method delivers medication deep into muscle tissue for rapid absorption into the bloodstream. Understanding its precise anatomical placement is important for safe and effective administration.
Anatomical Location
Accurate identification of the dorsogluteal site involves locating specific bony landmarks. One common method involves mentally dividing the buttock into four equal quadrants using imaginary lines. The target area for injection is the upper, outer quadrant, selected to avoid major nerves and blood vessels.
For more precise identification, two key bony landmarks are used: the posterior superior iliac spine (PSIS) and the greater trochanter of the femur. The PSIS is a prominent bony point at the top of the hip bone, near the dimples often visible on the lower back. The greater trochanter is a large, bony prominence on the upper thigh bone (femur), felt on the side of the hip.
An imaginary line can be drawn between these two points. The safe injection zone within the upper outer quadrant is typically considered to be above and lateral to this imaginary line. Some guidelines suggest locating the site about 5-8 cm below the iliac crest.
The muscle layers beneath the dorsogluteal site are primarily the gluteus maximus and, to a lesser extent, the gluteus medius. The gluteus maximus is the largest and most superficial of the gluteal muscles, forming a significant portion of the buttock’s shape. The gluteus medius lies deeper, beneath the gluteus maximus, and is a thick, fan-shaped muscle.
Considerations for Injections
Historically, the dorsogluteal site was a frequently chosen location for intramuscular injections due to its perceived large muscle mass and accessibility. Healthcare professionals traditionally used this site for various medications requiring deep muscle administration. However, contemporary medical practice has seen a significant decline in its recommendation and use for routine injections. The primary reason for this shift is the notable risk of complications associated with injections in this area.
A major concern is the close proximity of the sciatic nerve, the body’s longest and widest nerve. Accidental injection into or near the sciatic nerve can lead to severe pain, nerve damage, muscle weakness, and even paralysis or foot drop. Beyond nerve damage, the dorsogluteal area also contains major blood vessels, including the superior gluteal artery and vein. Injecting into a blood vessel can cause bleeding, hematoma formation, or lead to the medication being absorbed too quickly or inefficiently. Another challenge is the variable thickness of the subcutaneous fat layer in the dorsogluteal region. If the needle is not long enough or inserted improperly, the medication might be deposited into the fatty tissue rather than the muscle, leading to poor absorption and reduced effectiveness.
Due to these significant risks, safer and more consistently recommended intramuscular injection sites are now preferred. The ventrogluteal site, located on the side of the hip, is widely considered the safest option for adults and children over seven months old because it is deep and generally free of major nerves and blood vessels. Other alternative sites include the deltoid muscle in the upper arm and the vastus lateralis muscle in the thigh, which offer more predictable and safer injection environments.