Xie-Xie Dr. Xiaoming Zhang, Professor Dr. Ji-cheng Li, and Professor Dr. Lizhong Du

Teaching ObjectivesTeaching Objectives Gluteal Region Discuss the functional and clinical importance of the gluteal regionDiscuss the functional and clinical importance of the gluteal region Illustrate the muscles, nerve supply, and vasculature of the gluteal region, in the context of their clinical importanceIllustrate the muscles, nerve supply, and vasculature of the gluteal region, in the context of their clinical importance

Functional and clinical importance of the gluteal region?Functional and clinical importance of the gluteal region? Gluteal Region LocomotionLocomotion Site for intramuscular injectionSite for intramuscular injection Site for nerve injurySite for nerve injury Gateway for neurovascular structures to the perineumGateway for neurovascular structures to the perineum

LocationLocation Posterior region of the os coxae (pelvic bone or hip bone)Posterior region of the os coxae (pelvic bone or hip bone) Overview of the Gluteal Region

ContentsContents Gluteal muscles (three)Gluteal muscles (three) Nerves for the gluteal musclesNerves for the gluteal muscles Nerves for the lower limb, including the sciatic nerve (largest nerve in the body), and the perineumNerves for the lower limb, including the sciatic nerve (largest nerve in the body), and the perineum Vessels to the gluteal muscles and perineumVessels to the gluteal muscles and perineum

Gluteus maximusGluteus maximus Gluteus mediusGluteus medius Gluteus minimusGluteus minimus PiriformisPiriformis Superior gemellusSuperior gemellus Obturator internusObturator internus Inferior gemellusInferior gemellus Quadratus femorisQuadratus femoris Muscles of the Gluteal Region Gluteus maximus Gluteus medius

Deep musclesDeep muscles Gluteus minimusGluteus minimus PiriformisPiriformis Superior gemellusSuperior gemellus Obturator internusObturator internus Inferior gemellusInferior gemellus Quadratus femorisQuadratus femoris Muscles of the Gluteal Region

1. Gluteus maximus (cut) 2. Gluteus medius (cut) 3. Gluteus minimus Muscles of the Gluteal Region

Deep musclesDeep muscles 4. Piriformis 5. Superior gemellus 6. Obturator internus 7. Inferior gemellus 8. Quadratus femoris 8. Quadratus femoris Muscles of the Gluteal Region

Muscle Proximal attachment DistalattachmentActionInnervation Gluteus maximus Ilium behind the posterior gluteal line, sacrum, coccyx, and sacrotuberous ligament Iliotibial tract and gluteal tuberosity of the femur Powerfully extends the flexed femur at the hip joint; laterally stabilizes the hip and knee joints Inferior gluteal n. [L5,S1,S2] Gluteus medius Ilium between the anterior and posterior gluteal lines Greater trochanter Abduct the femur at the hip joint; hold the pelvis secure over the stance leg; prevent pelvic drop on the opposite swing side during walking; hip internal rotation Superior gluteal n. [L4,L5,S1] Gluteus minimus Ilium between the anterior and inferior gluteal lines Muscles of the Gluteal Region

Muscle Proximal attachment DistalattachmentActionInnervation Piriformis Anterior surface of the sacrum Greater trochanter Laterally rotate the hip joint N. to piriformis [S1,S2] Superior gemellus Ischial spine Superior gluteal n. [L4,L5,S1] Obturator internus Deep surface of the obturator membrane and surrounding bone Nerve to the obturator internus and sup. gemellus [L5,S1,S2] Inferior gemellus Ischial tuberosity Nerve to the inf. gemellus and quadratus femoris [L4,L5,S1] Quadratus femoris Lateral aspect of the ischium, just anterior to the ischial tuberosity Intertrochanteric crest Nerve to the inf. gemellus and quadratus femoris [L4,L5,S1] Muscles of the Gluteal Region

Functional and clinical importance of the gluteal regionFunctional and clinical importance of the gluteal region Gluteal Region LocomotionLocomotion Site for intramuscular injectionSite for intramuscular injection

Gluteal Region - Locomotion - Gluteus medius and minimus are key musclesGluteus medius and minimus are key muscles Hold the pelvis secure over the stance legHold the pelvis secure over the stance leg Prevent pelvic drop on the opposite swing-side during walkingPrevent pelvic drop on the opposite swing-side during walking

Gluteal Region - Site of Intramuscular Injection - Safe area for injections

Gluteal Region - Site of Intramuscular Injection - Tubercle of the iliac crest Anterior superior iliac spine Safe area (Gluteus medius) Location of the sciatic nerve

Gluteal Region Sciatic nerveSciatic nerve Largest nerve in the bodyLargest nerve in the body Located deep to the gluteus maximus and piriformis* musclesLocated deep to the gluteus maximus and piriformis* muscles * >87% of cadavers Spinal segments L4-S3Spinal segments L4-S3

Sciatic Nerve

Superior Gluteal Nerve

Functional and clinical importance of the gluteal regionFunctional and clinical importance of the gluteal region Gluteal Region LocomotionLocomotion Site for intramuscular injectionSite for intramuscular injection Site for nerve injurySite for nerve injury

Gluteal Region - Injury - Injury to the superior gluteal nerveInjury to the superior gluteal nerve Gluteus medius limp and gluteal gateGluteus medius limp and gluteal gate

Superior gluteal a and vSuperior gluteal a and v Inferior gluteal a and vInferior gluteal a and v Gluteal Vessels

Internal pudendal a and vInternal pudendal a and v Gluteal Vessels Internal pudendal a

Perineum - Today’s Word & Intellectual Challenge - The region that closes the pelvic outletThe region that closes the pelvic outlet Divided into two spaces (triangles)Divided into two spaces (triangles) Ischioanal (Anal) triangleIschioanal (Anal) triangle Urogenital (UG) triangleUrogenital (UG) triangle Means “modest or private”Means “modest or private” Relevant to the gluteal regionRelevant to the gluteal region Thoroughfare for the internal pudendal a and v, and pudendal nThoroughfare for the internal pudendal a and v, and pudendal n

Abdominopelvic Region Perineum

Perineum – 2 Triangles Sacrotuberous ligament

Coccyx Gluteus max m. Ext. anal sphincter m. Levator ani m. Sacrotuberous lig. Ischial tuberosity Scrotum Int. pudendal a. Pudendal n.

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