Components and Boundaries of the Gluteal Region
The gluteal region is the area posterior to the pelvic girdle between the iliac crest and the gluteal fold. The region comprises the following:
- Superficial gluteal muscles:
- Gluteus maximus
- Gluteus medius
- Gluteus minimus
- Tensor fasciae latae
- Deep gluteal muscles:
- Superior and inferior gemelli
- Obturator internus
- Quadratus femoris
- Superior and inferior gluteal
- Posterior femoral cutaneous
- Superior and inferior gluteal arteries (branches of the internal iliac artery)
- Superior and inferior gluteal veins (drain into the internal iliac vein)
- Greater and lesser sciatic foramina of the pelvis (formed by the sacrospinous and sacrotuberous ligaments)
- Superior: iliac crest
- Medial: intergluteal cleft
- Lateral: a line from the anterior superior iliac spine to the greater trochanter
- Inferior: inferior gluteal cleft
The gluteal muscles can be divided into 2 groups that are responsible for the main movements of the hip joint:
- Superficial gluteal muscles:
- Extension of the hip
- Abduction of the hip
- Stabilizing and maintaining balance of the pelvis during the gait cycle
- Deep gluteal muscles:
- External rotation of the extended hip
- Abduction of the flexed hip
Superficial gluteal muscles
|Gluteus maximus||Ilium posterior to the posterior gluteal line, posterior sacrum and coccyx, and sacrotuberous ligament||Iliotibial tract (75%) and gluteal tuberosity (25%)||Inferior gluteal nerve (S1, S2)|
|Gluteus medius||External ilium between the anterior and posterior gluteal lines||Greater trochanter of the femur||Superior gluteal nerve (L4, L5, S1)|
|Gluteus minimus||External ilium between the anterior and inferior gluteal lines||Greater trochanter of the femur|
|Tensor fasciae latae||Anterior superior iliac spine||Iliotibial tract to the lateral condyle of the tibia|
Deep gluteal muscles
|Piriformis||Greater trochanter (superior surface)||Anterior rami of S1|
|Gemelli||Greater trochanter (medial surface)|
|Obturator internus||Greater trochanter (medial surface)|
|Quadratus femoris||Intertrochanteric crest||N to the quadratus femoris (L5, S1)|
The superior and inferior foramina are formed by the following ligaments inserted into the bony pelvis:
- Sacrospinous ligament: extends from the lateral edge of the sacrum and coccyx to the ischial spine
- Sacrotuberous ligament: extends from the lateral edge of the sacrum and coccyx to the ischial tuberosity
The sacrospinous and sacrotuberous ligaments create the following foramina, or passageways:
|Greater sciatic foramen||Lesser sciatic foramen|
Two branches drain from the internal iliac arteries:
- Superior gluteal artery:
- The largest branch of the internal iliac
- Goes through the greater sciatic foramen and the suprapiriform foramen
- Supplies the gluteus medius, minimus, tensor fasciae latae, and piriformis muscles in the gluteal region
- Also supplies the skin over the sacrum and hip joint
- Inferior gluteal artery:
- Goes through the greater sciatic foramen and the infrapiriform foramen
- Supplies the gluteus maximus, obturator internus, and quadratus femoris muscles in the gluteal region
- Also supplies the sciatic nerve, pelvic floor, and skin of the gluteal and thigh regions
- The veins of the gluteal regions accompany the gluteal arteries and are named accordingly: superior and inferior gluteal veins.
- Drain into the internal iliac vein
- Several important nerves originating from the sacral plexus either traverse or have branches that innervate the gluteal region.
- The sciatic nerve, the largest branch of the lumbosacral plexus and largest nerve in the body, exits just caudally to one of the deep gluteal muscles, the piriformis muscle.
|Sciatic||Anterior and posterior divisions of the nerve roots L4-S3|
|Superior gluteal||L4-S1 (Sacral plexus)|
|Inferior gluteal||L5-S2 (Sacral plexus)|
|Posterior femoral cutaneous||S1-S3 (Sacral plexus)|
|Pudendal||S2-S4 (Pudendal plexus)|
|Sacral plexus||L4-S4 (direct branches)|
The following are clinically relevant to the gluteal region:
- Intramuscular injections: The superolateral region of the gluteal region is relatively free of nerves and vessels and is often used for intramuscular injections.
- Trendelenburg gait: abnormal gait secondary to the weakness of the hip abductors, primarily the gluteus medius and gluteus minimus muscles, which are essential to maintaining the balance of the pelvis during the gait cycle. Weakness of the hip abductors causes a drop of the contralateral pelvis while walking, or a Trendelenburg gait.
- Piriformis syndrome: Also called deep gluteal syndrome or wallet neuritis, piriformis syndrome is characterized by a combination of symptoms involving the hip, buttock, and upper thigh. Described as peripheral neuritis of the sciatic nerve and may be related to irritation of the same at the level of the piriformis muscle. May be caused by trauma, hematoma, excessive sitting, and anatomic variations of the muscle and nerve.
- Superior gluteal nerve palsy: occurs secondary to a peripheral injury of the superior gluteal nerve leading to motor loss, specifically involving the gluteus medius and minimus. Superior gluteal nerve palsy manifests as a Trendelenburg gait. The most common cause is an iatrogenic injury during hip surgery and intramuscular injection.
- Lesions of the inferior gluteal nerve: most commonly occur through iatrogenic injuries (e.g., surgery), trauma, hernias, or pelvic tumors. May lead to a functional deficiency of the gluteus maximus muscle, causing a “gluteus maximus lurch.” Patients present with difficulties walking up stairs or standing up from a chair.
- Drake, R.L., Vogl, A.W., & Mitchell, A.W.M. (2014). Gray’s Anatomy for Students (3rd ed.). Churchill Livingstone.