W10 lower extremity anatomy and pathologides Flashcards
what compose the knee joint?
femur, tibia, fibula, patella
what are two knee joint ligaments and where are they?
ACL – lateral femoral condyle to medial tibial condyle
PCL – antero-lateral femoral condyle to tibial plateau
what do meniscus in the knee do? what material and what shape?
Cushion join space= fibrocartilaginous and crescent shaped
what are two meniscus in the knee? what shape and where are they?
Medial – c-shaped, between femur medial condyle and tibial medial aspect
Lateral – circular and more mobile. Arises ligaments of Wrisberg and Humphry
what are the three gluteus muscles and where are they?
Gluteus maximus – from external ilium, dorsal sacrum and lateral coccyx, into gluteal tuberosity of femur. Posterior to iliotibial tract. Covers gluteus medius.
Gluteus minimus – from external ilium b/w ant and post gluteal lines, into lateral greater trochanter
Gluteus medius – from external ilium b/w inf and ant gluteal lines, into antero-lateral greater trochanter
what are two deep muscles and where are they?
Piriformis – superior deep muscle. From ant sacrum b/w ant sacral foramina, into medial superior greater trochanter
Quadratus femoris – most inferior deep muscle. From lateral sacrum, ant to ischial tuberosity, into intertrochanteric crest of proximal femur
what are the quadriceps and where are they?
Vastus medius – from anteromedial intertrochanteric line, into patella via quadriceps tendon Vastus intermedius – from upper 2/3 anterolateral femur, into patella via quadriceps tendon Vastus lateralis (largest) – from greater trochanter and linea aspera, into patella via quadriceps tendon Rectus femoris – from anteroinferior iliac spine into patella via quad tendon
what is the patellar tendon?
continuation of quadriceps tendon below patella.
where is the sartorius?
most superficial in anterior thigh. From asis, into tibial medial surface
where is the gracilis?
most superficial in medial thigh, descends vertically. From pubic ramus and body, into tibial body medial surface.
what are the three hamstrings muscles? where are they?
Biceps femoris – short head from ischial tuberosity, long head from femoral linea aspera, both into fibula head and tibial lateral condyle
Semitendinosus – from ischial tuberosity, into tibial medial surface proximal part
Semimembranosus – from ischial tuberosity, into tibial medial condyle
what are the three lower leg muscles?
Soleus – from fibula head and tibial medial border, into calcaneus via Achilles tendon
Gastrocnemius – from femur medial and lateral condyles and knee capsule, into calcaneus via Achilles tendon
Tibialis anterior – from tibial lateral condyle and body, and interosseous membrane, into first metatarsal and first cuneiform
what is the ankle composed of?
tibia, fibula, talus
what is the achilles tendon formed by? Where does it attach to?
junction of plantaris, gastrocnemius and soleus. Attaches to calcaneus posteriorly.
what bones are in the foot?
= calcaneus, navicular, cuboid, three cuneiform bones, metatarsals, phalanges and distal phalanges
what is especially prone to stress fractures in the foot?
base of 5th metatarsal
what are the four types of meniscal tear?
Horizontal tear= parallel to tibial plateau, divides meniscus into superior and inferior.
Longitudinal tear= perpendicular to tibial plateau, divides meniscus into medial and lateral.
Complex= combination of both horizontal and longitudinal.
Bucket handle= displaced longitudinal tear.
what are the two types of ACL tear?
Complete tear= ACL coils, fluid within and surrounding.
Partial tear= ACL thicken and frayed, fluid within and surrounding.
rare disease of joint lining (membranes, tendons or bursae) that can cause hemosiderin= ? affect what joints?
Pigmented villonodular synovitis (PVNS)
knee, shoulder, hip and elbow
inflammation of skeletal muscles (voluntary muscles)= ? cause? appearance in T1, T2 and T1 post-gad?
myositis
- cause: autoimmune (eg. lupus, scleroderma, rheumatoid arthritis), infection (HIV, drug), injury
- T1= hypo due to fluid, edema surrounding bone marrow, cortical bone destruction
- T2= hyper due to edema
- T1 post-gad= hyper due to bone marrow and abscess
thickening of tissue around nerve (nerve tumor) in bottom of the foot,
most between 3rd and 4th toes= ? symptoms? treatment?
morton’s neuroma
- feels like walking on marbles/ pebbles
- treatments cortisone injections, special footwear, surgery
cartilage and thin layer of the bone becomes loose from bone= ? cause? common population? affects what joint?
Osteochondritis dissecans
- caused by poor blood flow
- mostly in young men, post-injury
- affects knee, elbow, shoulder, hip, ankle
loss of blood in bone= ? common in what part of the bone? common sites?
Avascular necrosis
- common near a joint, mostly epiphysis of long bones (eg femur)
- common sites knee and hip joints
malignant bone tumor (femur common, also tibia and humerus)= ? appearance on T1, T1 post-gad, T2?
osteosarcoma
- T1= intermediate signal, solid component enhancing post-gad
- T2= surrounding edema
malignancy in bone mostly in children= ? What part of bone does it invade? appearance on T1 and T2?
Ewing’s sarcoma
affects pelvic bone, long bones, scapula, ribs, vertebrae
- invade bone cortex, destroy bone - weaken, pathological fractures
- T1= hypointense
- T2= hyperintense
= benign bone growth in epiphyseal plate (children)
What type of bone tissues in the growth?
Cartilage cap thickens becomes?
Cause?
What’s common? One or more?
Osteochondroma
- additional bone portion may contain bone cortex and medullary component with cartilage cap
- cartilage cap thickens= malignancy
- can be congenital
- one lesion in knee common
= benign growth in distal femur or proximal tibia metaphysics region, once epiphyseal plate closed
Common population?
Does it involve joint?
giant cell tumor/ osteoclastoma
- common in young adults
- do not involve joint
- MRI determines extend of bone marrow involvement and soft tissues
small (<1.5 cm) round lesion from osteoblastic cells= ? common bones?
osteoma/ osteoid
in mostly femur and tibia
- lucent center, dense outer layer of cortical thickening
- T1= center similar signal to musle
glenoid fossa not supporting femoral head - dislocated superiorly= ? what is seen surrounding the joint?
hip dysplasia
acetabular edema
bone bruises with edema= ? what technique useful to distinguish from fat? appearance on T1 and T2?
bone contusions
- fat sat tells fatty lesion vs bone marrow pathology
- T1= hypointense
- T2= hyperintense
Fracture from disease (eg. osteosarcoma) weakening bone cortex= ?
What type of bones more prone?
pathological fractures
weight-bearing bones more prone
overuse, sports, weigh-bearing (ie. calcaneus and base of 5th) fractures= ? appearance on T2?
stress fractures
- T2 (non fat sat) show fracture line within edema
excessive fluid in joint space due to age, arthritis, trauma, HIV, drug= ? where does excess fluid travel in the ankle?
bone effusion
- normal joint space show synovial fluid
- excess fluid travel upward pushing on muscles and tendons (Achilles)
synovial sac with fluid in popliteal fossa, at/ below knee joint= ?
baker’s cyst
what are three grades of collateral ligament tear and their appearances?
grade 1 - strain, high signal along ligament
grade 2- strain with fiber damage
grade 3- strain with destruction of fibers
What does diabetic foot lead to?
- in patients with diabetes mellitus (type 2)
- can lead to osteomyelitis and destroys bones due to inflammation
- neuropathic joint affect intertarsal joints causing erosion and possible dislocation
intraosseous cyst with pus, common in children= ? what is it related to? common in what bones?
osteomyelitis/ Brodie cyst
- realted to chronic osteomyelitis
- common in tibia (metaphysis), carpals, tarsal
