anterior compartment of thigh• sartorius• four large quadriceps femoris muscles(rectus femoris, vastus lateralis, vastusmedialis, and vastus intermedius).• the terminal ends of the psoas major• and iliacus muscles pass into the upperpart of the anterior compartment fromsites of origin on the posterior abdominalwall.
• The posterior compartment of thighcontains three large muscles termed thehamstrings. All are innervated by thesciatic nerve.
20.(L2-L4)largest branchboth motor and sensory.Emerges from the lateralborder of the psoas majorFlexors of the hip andextensors of the kneeSkin of the anterior andlateral thigh, medial legand foot
21.largest cutaneousbranch of the femoralnervecontinuation of thefemoral nerveSkin of medial aspectsof leg and foot
22.Emerges from the medialborder of the psoasmajorLeaves the lesserpelvis throughthe obturator canalSkin on the superiormedial thighAdductor muscles of theleg
Gluteal regiondeep group of small muscles,• piriformis, obturator internus, gemellussuperior, gemellus inferior, and quadratusfemoris;superficial groupgluteus minimus, gluteus medius, andgluteus maximus-• the tensor fasciae latae,
44.o Leaves thegluteal region bypassing deep tothe long head ofthe bicepsfemoris,at thelower margin ofthe quadratusfemoris muscleo Divides into thecommon peronealand tibialnerves, at avariable siteabove thepopliteal fossa
L4L5S1S2S3SemitendinosisBiceps femorissemimembranosusHamstringsGastrocnemiusand posteriorcompartment ofthe leg and footTibialnerveCommonperonealnerve Deep peronealnerveAnteriorcompartment oflegLateralcompartment of legSuperficial peronealnerveMotor Branches of theSciatic Nerve
Greater sciatic foramen• The greater sciatic foramen is formed on the posterolateral pelvic wall and is the major route forstructures to pass between the pelvis and the gluteal region of the lower limb . The margins of theforamen are formed by:• the greater sciatic notch;• parts of the upper borders of the sacrospinous and sacrotuberous ligaments;• the lateral border of the sacrum.••• The piriformis muscle passes out of the pelvis into the gluteal region through the greater sciaticforamen and separates the foramen into two parts, a part above the muscle and a part below:• the superior gluteal nerve and vessels pass through the greater sciatic foramen above thepiriformis;• the sciatic nerve, inferior gluteal nerves and vessels, pudendal nerve and internal pudendal vessels,posterior cutaneous nerve of thigh, nerve to the obturator internus and gemellus superior and thenerve to the quadratus femoris and gemellus inferior pass through the greater sciatic foramenbelow the muscle.•49
Lesser sciatic foramen• The lesser sciatic foramen is inferior to the greater sciatic foramenon the posterolateral pelvic wall .It is also inferior to the lateralattachment of the pelvic floor to the pelvic wall and thereforeconnects the gluteal region with the perineum:• the tendon of obturator internus passes from the lateral pelvic wallthrough the lesser sciatic foramen into the gluteal region to inserton the femur;• the pudendal nerve and internal pudendal vessels, which first exitthe pelvis by passing through the greater sciatic foramen below thepiriformis muscle, enter the perineum below the pelvic floor bypassing around the ischial spine and sacrospinous ligament andmedially through the lesser sciatic foramen.•51
Trendelenburgs Test• – assesses functioning of hip abductors• Stand behind patient and ask to stand onone leg for 30 seconds• Pelvis should tilt up on side of unsupportedleg = Trendelenburg negative (normal)• If pelvis tilts down towards unsupported leg =Trendelenburg positive (pathological)• Repeat for other leg53
A 51-year-old man experiences a loss ofskin sensation along the medialcompartment of the thigh. No otherareas of skin are affected. Which of thefollowing best describes the area of deficit?A. L2 dermatomeB. L3dermatomeC. L4 dermatomeD. Cutaneous field of the femoral nerveE. Cutaneous field of the obturator nerveF. Cutaneous field of the saphenous nerve
27. A 55-year-old man has difficultyextending his hip while walking up a flightof stairs.He experiences no cutaneousdeficits. Which damaged nerve is mostlikely responsiblefor causing this man’s symptoms?A. Inferior gluteal nerveB. S1 nerve rootC. S2 nerve rootD. Superior gluteal nerve
28. A 33-year-old man’s pelvis drops onthe right side whenhe steps with his right foot. He has nocutaneous deficits.Which nerve lesion is most likely causingthis problem?A. Femoral nerveB. Inferior gluteal nerveC. Obturator nerveD. Superior gluteal nerveE. Tibial nerve