Lower Limb Flashcards
lateral rotator group
musculature of the gluteal region
- primarily involved in lateral rotation of femur at hip
- lateral (external) rotator muscles
- located deep to gluteal muscles
what are the 6 lateral rotator muscles that run from the bony pelvis to the greater trochanter and upper posterior femur?
piriformis obturator internus superior and inferior Gemelli quandratrus femoris obturator externus
piriformis
- originates from pelvic surface of lateral part of sacrum
- leaves pelvic cavity through the greater sciatic foramen to attach to femur
obturator internus
- originates on obturator membrane of pelvis
- tendon exits pelvis through lesser sciatic foramen to insert onto femur
- pudendal canal formed with obturator membrane and carries structures that supply the perineum
superior gemelli
- the superior gemellus runs above the obturator internus
inferior gemelli
runs below the obturator internus
quadratus femoris
runs from ischial tuberosity to femur
obturator externus
runs from outer surface of the obturator membrane to the femur
blood supply of gluteal muscles
- branches of internal iliac artery
- primarily the superior and inferior gluteal arteries
- enter gluteal region through greater sciatic foramen (superior and inferior to the piriformis muscle)
- continue to travel along posterior surface of ilium (deep to gluteus maximus)
venous drainage of gluteal muscles
each arterial branch has a corresponding venous branch that travels alongside it – venous branches drain into internal iliac vein
innervation of the gluteal region arises from which plexus
the sacral plexus
- located deep to gluteus maximus
- pass through greater sciatic foramen
superior gluteal nerve
supplies motor innervation to gluteus medium, gluteus minimus and tensor fasciae latae
inferior gluteal nerve
supplies motor innervation to the gluteus maximus
posterior femoral cutaneous nerve
supplies sensory info to the skin of the posterior thigh
sciatic nerve
supplies the muscles that make up the posterior thigh – largest nerve in the body
pudendal nerve
supplies motor innervation to the anal sphincters and the urethral sphincters and sensory innervation to the perineum, penis, scrotum, labia majora and clitoris
what is the pathway of the sciatic nerve (L4-5 and S1-3)
- after forming the sacral plexus, leaves pelvis via greater sciatic foramen and emerges below piriformis muscle
- runs deep to gluteus maximus
- passes superficial to lateral rotator muscles where it enters the posterior thigh deep to hamstring muscles
- innervates muscles of posterior thigh (biceps femoris, semimembranosus and semiteninosus) and the hamstring portion of the adductor magnus
hip joint
ball and socket synovial joint between head of femur and acetabulum of hip bone
acetabular labrum
- rim of fibrocartilage that deepens the cavity of the acetabulum
- by deepening the acetabulum, more than half of the femoral head can fit
- greatly improves stability
ligamentum teres
- acts as a secondary stabilizer of the hip joint
- supplements work of capsular ligament
fibrous capsule
- thick and strong group of ligaments that help hold the femoral head in the acetabulum
- ligaments oriented in spiral fashion around the hip joint (tighten during extension and go slack during flexion)
- capsule is weakest in its posteroinferior region
compartments of the thigh
- compartments formed by intermuscular septa
- anterior compartment = quandriceps muscle group and sartorius muscle
- posterior compartment = hamstring
- medial compartment = adductors
adductors
- most are triangular in shape
- originates from pubis
- insert onto linea aspera of femur
- pectineus, adductor brevis, adductor longus, gracilis, adductor magnus
adductor magnus
- deepest and largest muscle of the medial compartment
- inserts along the length of the linea aspera
- adducts the thigh, can also extend and medially rotate the thigh at the hip joint
- at most distal insertion site, a smaller “hamstring” part inserts on the adductor tubercle of the femur (forms adductor hiatus)
- adductor hiatus allows passage of vessels between anterior and posterior thigh
hamstrings
- 3 muscles that originate from ischial tuberosity of ischium and insert on posterolateral (fibula) and posteromedial (tibia) aspects of knee
- extend hip and flex knee
the femoral triangle
- area in upper anterior thigh that contains major neurovascular structures
- bounded superiorly by inguinal ligament, laterally by sartorius muscle and medially by adductor longus muscle
- has a muscular floor (iliopsoas and pectineus) and roof formed mainly by fascia lata
blood supply of hip and thigh originates from which artery?
supplied by external iliac artery which passes deep to the inguinal ligament and continues as femoral artery
arterial branches to the hip
- deep femoral artery (profunda femoris) and circumflex arteries
- multiple branches that anastomose around neck of femur
arterial branches to the thigh
- profunda femoris artery (deep femoral artery) and superficial femoral artery
- profunda femoris artery is the main source of blood to thigh, femoral artery supplies the rest
venous drainage of thigh and lower limb
femoral vein
what is the longest tributary of the femoral vein
great saphenous vein (drains superficial tissues of most of the lower limb and empties into femoral vein in upper thigh)
pathway of femoral artery and vein
- the femoral triangle contains the femoral artery and vein
- descend through femoral triangle to its apex where they pass into the adductor (Hunter’s) canal deep to sartorius and superficial to adductor magnus
- from canal they pass through the adductor hiatus to the posterior knee where they become the popliteal artery and vein