Radiology Lower Limb Flashcards
3 types of fractured hips?
- Intertrochanteric fracture: greater to lesser trochanter
- Femoral neck: below head of femur
- Subtrochanteric Fracture: below lesser trochanter, entire bone must be stabilized
-most fractured hips are externally rotated, muscles pull on broken bones, shorten and rotate leg
Blood supply to femoral head? Danger of fracturing it?
- Medial Circumflex Femoral Artery comes off Deep Femoral and gives most blood supply to femoral head and neck
- could cause death to head, or inability to fully heal
How to test for Gluteus Medius and joint stability?
- stand on one leg, if there is a problem the hip will drop down (Trendelenberg Sign)
- if the person is old, it might be because the articular cartilage is worn down
- can happen if Superior Gluteal Nerve is damaged during surgery
Last bone to ossify? Clinical significance?
- iliac crest
- get X-ray of hand and pelvis to determine how much more growth a child has, wait to treat scoliosis
Why do women generally have genu valgus?
- women have wider pelvis
- femur is more angled to compensate
- affects knees over time
Hallux Valgus?
- lateral deviation of big toe
- medial deviation of 1st metatarsal
- adductor muscles pull
- develop exostoses (cartilage) or bunion on medial side of metatarsal head
- also called metatarsus primus varus
- surgery to correct: release adductors, take off exostoses, and realign bone
- may require arthroplasty: surgical reconstruction of proximal MP joint
Spina bifida in infants and risk of hip dislocation? How to fix it?
- posterior vertebrae don’t close during development, spinal cord is exposed
- nerves don’t work properly and femoral head dislocates
- Surgery to cut hole in pelvis and take Psoas Major and attach it to Greater Trochanter to prevent dislocation
- it becomes an abductor muscle instead of flexor
Order of vessels from lateral to medial that go under inguinal ligament?
- femoral nerve
- artery
- vein
- lymphatic
Risk of clot in femoral vein?
- Pulmonary Embolism
- anticoagulants to help
- put cage in there to prevent clot from reaching heart
Largest sesamoid bone in body? Function?
- Patella
- used as fulcrum in leg to help the quads do their job of extending the knee
How do you check to see if a baby hip is dislocated?
- femoral head not yet ossified so X-ray doesnt help
- Barlow Test to check for dislocation
- abduct too much and medial circumflex will be kinked and lead to necrosis of femoral head
Innervation of Pes Anserinus?
- Sartorius: Femoral
- Gracilis: Obturator
- Semitendinosus: Tibial division of Sciatic
-they function to internally rotate knee
ACL surgery?
- take Semitendinosus and Gracilis, cut the long tendon and fuse these muscles together
- use tendon as new ACL, drill holes in femur to feed it through
- bone fibers need to fuse into new tendon, could take one year
Osteochondritis desicans?
bone under cartilage dies due to lack of blood flow
Which direction does the patella want to dislocate?
- laterally
- valgus stance increases chance of patella moving laterally
- strengthen Vastus Medialis to pull patella more medially
What imaging technique shows meniscal or ACL tears?
MRI
How to test an achilles tendon tear?
- lie on stomach
- flex knee and squeeze gastrocnemius and soleus
- if the foot moves, the tendon is not torn
- if pain, could be plantaris tear
Outcome of Tibial fracture?
- hard to heal because superficial to skin, may lose leg
- supports most body weight (Fibula is not weight bearing- can remove bone for graft)
- if patient is smoker it may never heal
- need long leg cast to immobilize knee and foot joints
- if cannot fix with cast, put rod through medullary canal
Mangled extremity index?
- based on bone, muscle, skin lost and amount of contamination in wound
- used to see if you can save leg or need to amputate
What supports the lateral knee?
- Biceps Femoris
- LCL
Attachments of MCL?
adductor tubercle and goes deep to Pes Anserinus
Function of Sartorius?
Sartorial Slender:
- flex hip
- externally rotate
- abduct
Ankle Mortise?
- Medial Malleolus of Tibia and Lateral Malleolus of Fibula designed to keep Talus in place
- allows ankle to dorsi and plantar flex
- must be carefully fixed if fractured, lateral malleolus is more important
- AP xray to see relationship
- Fibula sits more posterior to Tibia, to really see relationship, need to internally rotate ankle to bring Fibula and malleoli into view
What goes under sustentaculum tali of calcaneus?
Flexor Hallucis Longus
-holds talus up
Fall from height, what’s fractured?
- Calcaneus fractured
- evaluate for compression fracture in thoracolumbar spine because they roll forward into flexion when they fall and compress vertebral bodies (lateral xray)
Role of Navicular bone? What supports it
- top of arch, supports arch
- Posterior Tibialis Tendon and Fibularis Longus
Jones Fracture
- Fibularis Brevis attaches to 5th metatarsal
- during ankle roll, can break tuberosity off
March Fracture?
- crack in 2nd or 3rd metatarsal
- stress fracture from jogging or marching
Function of Quadratus Plantae?
- Flexor Digitorum Longus comes around medial malleolus and attaches to toes at an angle
- Quadratus plantae attaches to the tendons at an oblique angle to pull the digitorum straight
Sesamoid bones in foot?
- medial and lateral, or fibular and tibial
- form under metatarsal head of big toe in the tendon of Flexor Hallucis Brevis
- Flexor Hallucis Longus tendon runs through these bones
Lisfranc Fracture?
- injury at base of metatarsals where cuboid and cuneiforms are
- difficult to diagnose because hard to get a lateral view
How to see if problem with arch on xray?
must be weight bearing xray
Pes planus?
- flat arch
- most are born with it, some athletes have it
- can be pathological due to tearing of Tibialis Posterior or ligaments in foot
- can be due to abnormal or fusion of tarsals
- problem because you walk and put weight on inside of arch, pronating foot on navicular bone, will stretch ligament over time
Plantar Fasciitis?
- help support arch
- need good arch support if on feet a lot
- can cause bone spur off calcaneus
- due to inflammation of fascia
Foot deformities in babies?
- Congenital club foot (Talipes Equinovarus)
- Talus becomes vertical and toes go against Tibia
- may need to cut ligaments and put them in place, put in a cast and change it every week
Compartment Syndrome?
- pressure within crural fascia compartments is high
- bleeding and swelling will squeeze muscles
- blood cannot leave, waste products remain, low O2
- could be from severe crush injury or Tibial injury
- could become necrotic and lose leg
- need to release pressure with surgery, muscle squeezes through incisions
- cover with skin grafts
