Gluteal Region, Posterior Thigh, and Popliteal Fossa PDF

The Gluteal region, Posterior thigh and Popliteal fossa Mange Manyama, M.D., Ph.D. I do not have financial interest in commercial products or services related to the subject of this lecture...

The Gluteal region, Posterior thigh and Popliteal fossa Mange Manyama, M.D., Ph.D. I do not have financial interest in commercial products or services related to the subject of this lecture PollEv.com/ manyama837 October 22, 2024  Suggested readings: Essential Clinical Anatomy - Moore’s 6th Ed. P. 441-452 Gluteal muscles Posterior thigh muscles Nerves and vasculature of posterior thigh and gluteal region Popliteal fossa Injury to the superior gluteal nerve Hamstring injuries Sciatic nerve injuries Intragluteal injections  Learning objectives Identify the bony landmarks in the gluteal, thigh and popliteal region Identify the muscles of the gluteal region and posterior thigh; describe their attachments, nerve supply and actions Identify the neurovascular structures of the gluteal region and posterior thigh Describe the boundaries and contents of the popliteal fossa Discuss some of the clinical correlations in these regions  Gluteal region The greater sciatic foramen is the passageway for structures entering or leaving the pelvis (e.g., sciatic nerve), whereas the lesser sciatic foramen is the passageway for structures entering or leaving the perineum (e.g., pudendal nerve). Posterolateral surface of ilium serves as an attachment for the gluteal muscles. Ischial tuberosity – serves as a proximal attachment of the hamstring (Semitendinosus, semimembranosus, and long head of biceps femoris) muscles.  The greater trochanter provide attachments to the abductors and medial rotators of the hip. The Gluteal tuberosity – attachment for part of the gluteal maximus muscle.  Muscles of the gluteal region The superficial layer - Consist of three glutei (maximus, medius, and minimus) and tensor fasciae latae muscle –The proximal attachment for the three glutei muscles is on the posterolateral surface of the ilium. –Distal attachment for G. maximus - gluteal tuberosity & iliotibial tract; G. medius and G. minimus - greater trochanter –Innervation: G. maximus – inferior gluteal nerve; G. medius, G. minimus and Tensor fascia latae – superior gluteal nerve Arteries and Nerves of Thigh: Posterior View  Actions of the Glutei muscles Gluteus maximus extends and laterally rotates the thigh. Plays a key role in rising from sitting position and during walking uphill. Gluteus medius and minimus are abductors and medial rotators of the thigh When standing on one limb, the gluteus medius and minimus of the grounded limb fix the pelvis so that it does not sag to the unsupported (lifted) side. This action keeps the pelvis level and enables the non-weight-bearing limb to clear the ground during the swing phase of walking. When a person with paralysis of gluteus medius and minimus is asked to stand on one leg (on the side of the affected muscles), the pelvis on the side of the lifted lower limb descends. This is referred as a positive Trendelenburg sign.  Arteries and Nerves of Thigh: Posterior View The deep layer consists of Piriformis, Obturator internus, Superior and Inferior gemelli, and Quadratus femoris muscles Innervation: Piriformis muscle - Ventral rami S1 and S2 , Obturator internus and superior gemellus - Nerve to obturator internus, Quadratus femoris and inferior gemellus - Nerve to quadratus femoris Actions: Lateral rotators of the thigh and steady femoral head in acetabulum  Muscles of the posterior thigh region Semitendinosus, semimembranosus, and long head of biceps femoris (collectively known as hamstring muscles). Features: –Proximally attached to ischial tuberosity, distally to the bones of the leg; Innervation by the tibial division of sciatic nerve –Act at the hip and knee joints to produce extension at the hip joint and flexion at the knee joint. Short head of the biceps femoris - arises from the lateral lip of linea aspera. Innervated by common fibular division of sciatic nerve Hamstring injuries – Results from tear of proximal attachments of the hamstrings to the ischial tuberosity or tear of muscle fibers Nerves of the Gluteal and Posterior thigh regions Most are branches of the sacral plexus in the pelvis. Reach the gluteal region after passing through the greater sciatic foramen. Sciatic nerve – L4-S3. Divides into the tibial and common fibular nerves in the distal part of the thigh. The sciatic nerve innervates muscles on the posterior thigh, all leg and foot, and skin of most of the leg and foot. Piriformis syndrome - compression of the sciatic nerve by the piriformis muscle Intramuscular injections are usually done on the superolateral quadrant of the buttock because it’s relatively free of nerves and vessels. Damage to sciatic nerve results into weakness in extending the hip, inability to flex the leg. All ankle and foot movements are lost as well.  Arteries of the gluteal and posterior thigh regions Arteries of the gluteal region include the superior and inferior gluteal arteries - branches of internal iliac A. The posterior compartment of the thigh receives arterial supply through the four perforating branches from profunda femoris artery, inferior gluteal, medial circumflex femoral, and popliteal arteries.  Popliteal fossa A compartment posterior to the knee, bordered by posterior compartment muscles of the thigh and leg. The small saphenous vein pierces the deep fascia to drain into the popliteal vein. Popliteal vein Small saphenous vein Contents of the Popliteal Fossa Popliteal artery - Continuation of femoral artery at the adductor hiatus. – Deepest (anterior) structure in the fossa directly on the popliteal surface of the femur. – Genicular branches of the popliteal artery supply the capsule and ligaments of the knee joint. Popliteal vein - Continuation of the posterior tibial vein. Becomes femoral vein at the adductor hiatus Tibial and Common fibular (peroneal) nerves: Terminal branches of sciatic nerve. Termination of the small saphenous vein into the popliteal vein.