MSK Lower Limb Clinical Flashcards
Fractures of the pelvis (2)
Fracture of the pubic rami or avulsion fracture of the ischial tuberosity (hamstring muscles tear off a piece of the ischial tuberosity- rapid contraction/relaxation sports like sprinting)
Intracapsular fracture of the femur
Description
Causes
Presentation
Fracture within capsule of hip joint (fracture of the neck of femur/ broken hip)
Causes: elderly women post menopausal osteoporosis, minor trip/stumble
Presentation: distal fragment pulled upwards and laterally (shortened leg, laterally rotated)
Damage to medial femoral circumflex artery leads to avascular necrosis
Extracapsular fracture of the femur Description and types Causes Presentation Treatment
Description: fracture of the femur, outside of the joint capsule.
Trochanteric fracture, subtrochanteric fracture (fracture of femur below lesser trochanter), intercondylar fracture (damage to popliteal artery and misalignment of knee joint)
Causes: high energy road traffic accident
Presentation: blood supply to head of femur remains intact (no AVN), leg shortened and laterally rotated due to distal fragment being pulled upwards and laterally
treatment: dynamic hip screw
Surgical hip replacement
Plastic socket replaces acetabulum
Stainless steel femoral stem and head replaces femur
1/3 of people die within a year of hip replacement
Medial malleolus fracture
Spiral fracture.
Causes: twisting/rotating ankle, tripping/falling, car accident, over inversion
Presentation: if fibula is not fractured it supports the tibia -> minimal displacement
Tibial shaft fractures
Shaft is narrowest at junction between middle and inferior third (little blood supply -> poor healing)
If nutrient artery is damaged: predisposes patient to non union of bone fragments
Transverse stress fracture: indirect force applied to tibial shaft with bone turns with a fixed foot during a fall
Diagonal fracture: high speed forward fall. Limb shortens due to overriding bone fragments
Lateral malleolus fracture
Causes: twisting/rotating ankle, tripping/falling, car accident, over eversion (transverse fracture), external rotation of ankle (spiral fracture)
Talus fracture
Neck is fractured during dorsiflexion (neck pushed into tibia)
Body is fractured when jumping from height
The malleoli hold the fragments together -> minimal displacement
Avascular necrosis due to poor blood supply
Calcaneal fracture
Jumping from height, large force on heel.
Talus driven into calcaneus -> crushes it -> comminuted fracture
Presentation: disabling as it disrupts talocalcaneal joint
Metatarsal fractures
Blow to foot (drop heavy object on foot), stress fracture (athletes), excessive inversion (fibularis brevis causes an avulsion fracture of the base of metatarsal 5)
Presentation: usually 2nd, 3rd, or 4th metatarsal. Pain and swelling
Congenital dislocation of hip joint
8x more common in girls (1.5/100 births)
Femoral head not placed correctly within acetabulum during development-> dislocated joint
Presentation: inability to abduct, affected leg is shorter, positive trendelenburg sign due to superior gluteal nerve damage
Acquired dislocation of femoral head
Posterior more common than anterior as it is the weakest part of the joint capsule (less ligaments)
Posterior: traumatic accidents. Femoral head forced posteriorly through inferior and posterior parts of joint capsule. Leg is shorter and medially rotated. Potential damage to sciatic nerve -> paralysis of hamstrings/all muscles distal to knee (and sensory loss)
Anterior: caused by extension, abduction and lateral rotation in traumatic accidents. Femoral head ends up anterior and inferior to acetabulum and pulls acetabulum labrum with it.
Palpation of femoral artery
Continuation of external iliac artery (becomes femoral after passing under inguinal ligament). Branches into profunda femoris in femoral triangle (profunda femoris supplies most of thigh)
Femoral pulse can be palpated at the midinguinal point (halfway between pubic symphysis and ASIS)
Pulled groin (pulled adductor muscle)
Muscle strain in the medial compartment of the thigh
Cause: sports that require explosive movements/extreme stretching
Proximal part of muscle usually most vulnerable. Tears near the origin
Hamstring strain
Strain- excessive stretching or tearing of muscle fibres
cause: athlets (running, kicking sports)
Causes damage to muscle fibres and may rupture surrounding blood vessels -> forms a haematoma but remains contained by overlying fascia lata
Saphenous vein
Great saphenous vein graph (reversed due to valves) used for coronary artery bypass grafting
Stripping of the saphenous vein- procedure done if varicose veins are particularly bad. Prevents stasis of blood and formation of venous ulcers, typically near the medial malleolus.
May damage saphenous nerve in procedure. Pain/paraesthesia.complete loss of sensation in medial lower leg
Trendelenberg sign
Superior gluteal nerve damage/lesion -> paralysis of gluteus medius and gluteus minimus, so when contralateral leg si raised, the pelvis becomes unsupported and drops.
Ie. With SG nerve damage on your right side, if you lift your left leg your right glut med/min wont be able to contract as they are paralysed so your left pelvis drops
Intramuscular injection in the gluteal region
Divide one buttock into 4
Injection should be given in the upper outer quadrant
High risk of hitting sciatic nerve, blood vessel or bone
Ligament injuries of the knee
Presentation:
Swelling, pain and instability over site of damage. PCL and ACL damage causes difficulty walking
Assess:
Medial and lateral collateral ligament damage is assessed by passively rotating the a flexed lower limb. Pain on medial rotation- medial damage. Pain on lateral damage- lateral damage.
Anterior and posterior cruciate ligament damage is assessed by anterior/posterior drawer test (pull tibia forward- ACL damage, push tibia posteriorly- PCL damage)
Causes:
MCL- force applied to lateral side of knee when foot is fixed on ground
LCL- force applied to medial side of knee when foot is fixed on ground
ACL- force applied to back of knee when joint is partially flexed
PCL- dashboard injury (force applied to shins when knee is flexed, tibia pushed posteriorly) or hyperextension
Medial meniscus tear
Medial collateral ligament is firmly attached to medial meniscus
If one gets damage, its likely to cause damage to the other
Unhappy triad
Blow to lateral side of knee or lateral twisting of a flexed knee
Causes ACL damage as ACL is taut during flexion-> medial shift of unstable femur -> MCL tear -> medial meniscus tear
Housemaids knee
Prepatellar bursitis (swelling on the anterior side of knee) Due to friction between skin and patella
Clergymans knee
Infrapatellar bursitis due to friction between skin and tibia
Coronary angiography
Catheterise femoral artery within femoral triangle (midinguinal point)
Tube is navigated up external iliac artery, common iliac artery, aorta and into coronary vessels
Dye used to identify coronary occlusions
