Gross Anatomy
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Lower Limb
Lower Limb Forum 1) Describe the content of the subinguinal hiatus Lacuna musculonervosa Iliopsoas covered by fascia Femoral nerve Lateral cutaneous femoral nerve Femoral sheath – lateral vasorum Femoral artery Femoral nerve Lacuna lymphatica 2) Describe the borders and content of the femoral triangle Superiorly by the inguinal ligament, Laterally by the sartorius muscle, and Medially by the adductor longus (brevis is deep). 3) Describe the walls and content of the adductor canal Borders are Sartorius muscle (anteromedial), Adductor longus and magnus (posterior), and Vastus medialis (lateral). The canal contains the end of the femoral artery and vein, deep lymph vessels, the saphenous nerve, the nerve to vastus medialis, and the end of the obturator nerve. 4) Describe the adductor hiatus The gap in adductor magnos so the adductor canal vessels can get to the politeal space. Contains the politeal vein and arteries. James Lamberg 5) Describe the borders and contents of the popliteal fossa Contains NeVA: Tibial nerve (sciatic nerve), the common perineal nerve branches lateral from sciatic nerve, politeal artery, and popliteal vein.
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Gross Anatomy
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Lower Limb
6) Describe the pathogenesis of the Baker’s cyst and the prepatellar bursitis Prepatellar bursitis: Fluid filled bursa protrusion on the front of the patella from working on your knees a lot (e.g. kneeling for gardening work) Baker’s cyst: Popliteal cyst, so protrusion of capsule of knee joint, posteriorly. Check for a pulse to make sure it isn’t a popliteal aneurysm. 7) Describe the pathogenesis of the foot drop Damage to the common peroneal (fibular) nerve. No dorsiflexion or eversion anymore, thus food will be plantar flexed and inverted (dragged) while walking. A common injury would be trauma to the lateral knee causing the fibular head to break, and thus damaging the peroneal nerve. 8) Describe the unhappy triad and the Pott fracture Unhappy (terrible) triad: Injury to the knee while the foot is flexed and the hips are rotated. It wrecks the “money maker” (ATM): ACL, Tibial collateral ligament, Medial meniscus Pott’s fracture: Injury to the ankle by falling onto an everted foot while twisting. It wrecks the fibula (fracture), tears the anterior tibiofibular ligament, and fractures the medial maleolus above the deltoid ligament 9) Describe the cutaneous innervation of the lower limb
10) Describe the borders of the femoral canal and the symptoms of the femoral hernia The femoral canal goes from the inguinal region to the femoral triangle. The femoral sheath Version: 09Apr2009
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Gross Anatomy
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covers the triangle except for the saphenous hiatus. Bowel would travel through the femoral ring and out the saphenous hiatus. The femoral hernia would show a bulge below the inguinal line/ligament and is more common in women.
11) Describe the pes anserinus The insertion point on the lateral knee for the sartorius (femoral inneration), gracilis (obturator innervation), and semitendinous (sciatic innervation). 12) Describe the course of the saphenous nerve and the descending genicular artery The saphenous nerve is a cutaneous posterior branch of the femoral nerve, which runs through the adductor canal and pierces the vastoadductor membrane as it is leaving the canal. It runs inferiorly and medially where it passes between the tendons of sartorius and gracilis. It then runs inferior down the medial side of the leg in company with the great saphenous vein. It passes in front of the medial malleolus and along the medial border of the foot, where it terminates in the region of the ball of the big toe. The descending genicular artery runs in the adductor canal with the femoral artery. It perforates the vastoadductor membrane, leaving the adductor canal and descends on the medial side of the knee passing between the sartorius and gracilis to the knee. 13) Describe the venous circulation of the lower limb The great saphenous vein arises from the medial side of the dorsal venous arch and passes upward directly in front of the medial malleolus. It continues to run superiorly on the medial side of the thigh and passes through the lower part of the saphenous hiatus where it drains into the femoral vein. Version: 09Apr2009
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The small saphenous vein arises from the lateral part of the dorsal venous arch and runs behind/posterior to the lateral malleolus. It continues superiorly on the lateral side and up the middle of the posterior side of the leg where it runs between the two heads of the gastrocnemius muscle at the lower part of the politeal fossa, draining into the popliteal vein. 14) Describe the anatomy of the lesser and greater sciatic foramina The greater sciatic foramen is formed by the greater sciatic notch of the hipbone and the sacrotuberous and sacrospinous ligaments. It provides an exit from the pelvis into the gluteal region. It contains: Piriformis Sciatic nerve Posterior cutanous nerve of the thigh Superior and inferior gluteal nerves Nerves of the obturator internus and quadratus femoris Pudendal nerve Superior and inferior gluteal arteries and veins Internal pudendal artery and vein The lesser sciatic foramen is formed by the lesser sciatic notch of the hipbone and the sacrotuberous and sacrospinous ligaments. It provides an enterance into the perineum from the gluteal region. It contains: Tendon of the obturator internus muscle Nerve to obturator internus Pudendal nerve Internal pudendal artery and vein 15) Describe the ligaments supporting the plantar arch Medial arch – plantar calcaneonavicular ligament (spring arch) With hyaline cartilage that prevents talus from sinking between the calcaneus and navicular bones Connects anterior margin of sustentaculum tali of calcaneus to plantar surface of navicular Also supports head of talus Helps maintain the medial longitudinal arch of the foot Strengthened by deltoid ligament of the ankle joint and supported inferiorly by the tendon of tibialis posterior Lateral arch – two ligaments span the calcaneocuboid joint Long plantar ligament (long calcaneocuboid ligament) Longest of all ligaments of tarsus Attached behind to plantar surface of calcaneus in front of tuberosity on the plantar surface of cuboid bones (Linfranc’s joint line) Ligament converts groove on plantar surface of cuboid into canal for the tendon of fibularis longus Short plantar ligament (plantar calcaneocuboid ligament) Deep to long plantar ligament Short but wide band of great strength From calcaneus to tuberosity of cuboid bone 16) Describe the arterial supply of the femoral head and the possible fracture sites Version: 09Apr2009
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The femoral head is supplied by the: * Artery of the ligamentum capitis femoris into the fovea and acetabular branch of the obturator artery; it is a branch of the internal iliac artery * Ascending branch of the medial circumflex femoral artery from the deep femoral artery; anastamotic ring around the femoral neck * Ascending branch of the lateral circumflex femoral artery from the deep femoral artery; anastamoses with ascending branch of lateral circumflex; mainly supplies the head and neck of femur If the femoral neck breaks, blood supply distally may be lost. From the descending branch of medial and lateral circumflex femoral artery and from the deep femoral artery. If fractured below the neck, circumflex arteries will supply the head of the femur. If fractured within the capsule, necrosis may occur.
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