Understanding the Dorsal Gluteal Region: Anatomy, Clinical Significance, and Modern Best Practices

Introduction: A Historical Injection Site Reevaluated

For generations, the dorsal gluteal region represented the archetypal location for intramuscular injections. Nurses and clinicians were routinely trained to administer medications in this fleshy area, trusting its substantial muscle mass to absorb therapeutics effectively. Today, this once-standard practice faces increasing scrutiny, replaced by safer, evidence-based alternatives. The dorsal gluteal—also called the dorsogluteal site—specifically targets the upper outer quadrant of the buttock overlying the gluteus maximus. Though historically favored for accommodating large medication volumes, its proximity to critical neurovascular structures demands a thorough understanding of its anatomy and inherent risks to prevent devastating complications like sciatic nerve injury. Modern research and revised guidelines now prioritize patient safety through anatomical precision and site selection, reshaping clinical protocols worldwide.

Anatomical Landscape: Navigating a Complex Terrain

Muscles and Landmarks

The dorsal gluteal region centers on the gluteus maximus, the body’s largest and most superficial buttock muscle. It originates from the posterior iliac crest, sacrum, and coccyx, inserting into the iliotibial tract and femur. Injections here rely on precise surface anatomy:

1. Posterior Superior Iliac Spine (PSIS): The bony prominence at the base of the lower back.
2. Greater Trochanter: The lateral protrusion at the femur’s top.

An imaginary diagonal line connecting these two points bisects the buttock into quadrants. The recommended injection zone resides in the upper outer quadrant—approximately 5–8 cm below the iliac crest—housing the thickest portion of the gluteus maximus. Critically, this site avoids deeper structures like the sciatic nerve, which travels inferomedially, and the superior gluteal artery, which emerges above the piriformis muscle. Failure to landmark correctly risks perforating these vital tissues, turning a routine procedure into a medical emergency.

Fat Distribution Variability

Unlike deeper gluteal muscles, the dorsal site exhibits inconsistent soft-tissue composition. Subcutaneous fat here ranges from 1–9 cm thick across individuals, varying by body habitus, sex, age, and ethnicity. This unpredictability jeopardizes injection efficacy—a needle calibrated for intramuscular delivery may deposit medication into fat in patients with thick adipose layers. Since fat absorbs drugs more slowly than muscle, this can lead to altered pharmacokinetics: delayed onset, reduced bioavailability, or even tissue irritation. Recent ultrasonography studies confirm that up to 20% of dorsogluteal injections miss muscle entirely, particularly in females with wider pelvises or those with obesity.

Technique: Locating the Safe Zone (When Use Is Unavoidable)

1. Positioning: Place the patient prone with toes pointed inward (internally rotated hips). Standing patients may bend over a surface—but muscle flexion increases injury risk.
2. Landmarking:
   • Palpate the PSIS and greater trochanter.
   • Trace an imaginary line between them.
   • Inject only into the outer upper quadrant, medial to the trochanter but above the sciatic nerve pathway.

1. Injection Protocol:
   • Pinch-fat technique is contraindicated—stabilize skin flat.
   • Insert a 1.5-inch (or longer for large adults) needle at a 90° angle.
   • Aspirate before injecting; although debated, this remains a precaution against vascular entry.
2. Post-Procedure: Rotate sites if injections are recurrent to prevent fibrosis.

The "Z-track method" is highly recommended—pulling skin laterally before insertion seals the medication path upon release to minimize leakage and cutaneous irritation.

Complications: Why the Dorsal Gluteal Poses Risks

Sciatic Nerve Injury

The sciatic nerve lies perilously close to the dorsogluteal site. A misplaced injection or deep-drug diffusion can cause transient or permanent paralysis, sensory loss, and chronic neuropathic pain. An estimated 5–14% of patients with sciatic injury trace it to gluteal injections. Diabetics are disproportionately affected due to microvascular vulnerability. Recovery may require months of rehabilitation, nerve grafting, or remain incomplete—an unacceptable outcome for routine care.

Vascular and Infectious Hazards

Inadvertent penetration of the superior gluteal artery causes hematomas or pseudoaneurysms needing surgical intervention. Additionally, quadrant proximity to the rectum heightens contamination risk; improper skin disinfection invites abscesses or necrotizing infections. Studies report higher rates of subcutaneous nodules and granulomas in dorsogluteal sites versus alternatives, indicating chronic tissue damage.

Ventrogluteal Site: The Evidence-Based Alternative

The ventrogluteal site (over the gluteus medius/minimus) emerges as the preferred IM location according to WHO guidelines and recent meta-analyses. Here’s why:

• Enhanced Safety: Located further from major nerves/vessels.
• Consistent Muscle Depth: Uniform fat layer (~2–5 cm) ensures reliable intramuscular deposition across body types.
• Patient Comfort: Reduced pain scores during injection and recovery.

Comparative studies reveal 94% success rates for intramuscular placement in ventrogluteal sites versus 82% in dorsogluteal regions. Countries like New Zealand and UK have largely abandoned dorsogluteal injections in institutional protocols.

Modern Guidelines and Rational Usage

When to Avoid Dorsogluteal Injections

• Pediatric, elderly, or underweight patients
• People with paralysis/neuropathies
• Anticoagulant users (risk of hemorrhage)
• Repeated administration regimens

Contexts Where It May Still Be Used

In resource-limited settings lacking anatomical training tools, practitioners may resort to dorsogluteal injections if landmarks are impeccably identified. Some clinicians cautiously use it for single-dose antibiotics or vaccinations in robust adults with palpable anatomy. Volumes should not exceed 4 mL to mitigate tissue pressure. Nevertheless, upgrading to ventrogluteal techniques with simulation-based training is strongly advocated via guidelines from groups like the Infusion Nurses Society.

Conclusion: Prioritizing Safety Through Anatomy

The dorsal gluteal site retains a fraught legacy in medical history. While its muscle bulk theoretically accommodates large-volume injections, variable landmarks and erratic fat deposits render it anatomically treacherous. The unparalleled risks to neurovascular structures underscore why leading institutions now advocate abandoning it altogether for the ventrogluteal alternative—or at minimum, reserving it for rare scenarios combining perfect patient selection with expert landmarking. As precision medicine evolves, embracing evidence-based techniques minimizes preventable harm, transforming injections from perilous procedures into safer therapeutic gateways. Ultimately, informed anatomical competence defines clinical excellence—protecting patients while optimizing outcomes.