Pelvis and Hip Flashcards
What are the 6 landmarks that designate an intact acetabulum?
- acetabular roof
- anterior rim
- posterior rim
- iliopubic line
- ilioischial line
- radiographic teardrop
The iliopubic line represents the _____ column and the ilioischial line represents the _____ column
anterior
posterior
What does the anterior lip of the acetabulum represent?
The anterior margins of the acetabular cup
What does the posterior lip of the acetabulum represent?
The cortical rim of the acetabular cup
What does the acetabular roof represent?
The superior cortical aspect of the acetabular cup, which corresponds to the major weight-bearing portion of acetabulum
What is Klein’s line?
The line drawn along the lateral femoral neck intersecting the femoral head bilaterally
What is the most common disease affecting the hips?
Degenerative joint disease (DJD), aka osteoarthritis
What is the clinical presentation of hip DJD?
- increased pain upon weight-bearing
- loss of ROM
- loss of joint congruity
What are the 5 radiographic hallmarks of hip DJD?
- Joint space narrowing
- Sclerotic subchondral bone
- Osteophyte formation at joint margins
- Cyst or pseudocyst formation
- Migration of femoral head
Cysts associated with hip DJD are the result of what?
The degeneration of articular cartilage which results in microfractures in the subchondral bone which permits the intrusion of joint synovial fluid into periarticular bone
Cysts in the acetabulum are called what?
Egger’s cysts
In what direction does the femoral head migrate in DJD?
superomedial
What are 5 surgical interventions that may be necessary in patients with hip DJD?
- Wedge osteotomy
- Femoral head and neck resection
- Hemiarthroplasty
- Total hip arthroplasty
- Hip resurfacing
When can hip resurfacing be used over hip arthroplasty?
In younger patients with good bone density
What is RheumatoidArthritis?
a progressive, systemic, autoimmune inflammatory disease primarily affecting synovial joints
Does RA affect men or women more often?
Women, 3 times more
When is RA onset most common?
In young adulthood
What are the 6 clinical features of RA?
- Morning joint stiffness
- Bilateral and symmetrical swelling of joints
- Pain and functional disability
- Rheumatoid nodules
- Positive rheumatoid factor test
- Radiographic changes consistent with RA
RA of the hip is characterized by what 7 things?
- Osteoporosis of periarticular areas
- Symmetrical and concentric joint space narrowing
- Articular erosions located either centrally or peripherally in joint
- Synovial cysts located within nearby bone
- Periarticular swelling and joint effusions
- Axial migration of femoral head
- Acetabular protrusion
Where is osteoporosis seen first in the hip joint?
In the femoral head
As hip joint spaces narrow in what direction does the femoral head migrate?
Axially into the acetabulum, which can cause acetabular protrusion (an expansion of the acetabulum into the pelvis)
When do articular erosions become evident?
When joint surfaces lose their optimal congruity
- Spherical shape of femoral head becomes distorted and acetabulum loses its cuplike appearance
What is the distinct difference between DJD and RA?
RA has minimal or absent reparative processes which means radiographic features such as sclerotic subchondral bone and osteophyte formation (hallmarks of DJD) are not features of RA
What are 5 treatment options for RA patients?
- Non-steroidal anti-inflammatories (NSAIDs)
- Corticosteroids
- Gold salts
- Immunosuppressive drugs
- Rehab to focus on pain relief modalities, splinting, adaptive functional and ambulatory devices, and exercise to promote strength/ROM to minimize deformity
What causes AVN of the hip?
An interruption of blood supply to the femoral head causing bone tissue death
If AVN affects local segments of bone what is it called?
osteochondritis dissecans
If AVN affects an entire epiphysis in a growing child what is it called?
epiphyseal ischemic necrosis
Where is the most common location for epiphyseal ischemic necrosis to occur?
In the proximal femur
What are the 3 categories in which disruption of blood supply to the femoral head is divided?
- Conditions that result in external blood vessel compression or disruption near/within bone such as trauma, infection, or steroid administration
- Conditions that result in blood vessel occlusion because of thickening of vessel wall such as radiation therapy, systemic lupus erythematosus, or giant cell arteritis
- Conditions that result in blood vessel blockage from thromboembolic process such as alcoholism, diabetes, or sickle cell disease
Epiphyseal ischemic necrosis is aka what?
Legg-Calvé-Perthes disease
What type of patient is Legg-Calvé-Perthes disease seen predominantly?
in young boys with average age around 6 years
What is the clinical presentation of Legg-Calvé-Perthes disease?
Non-specific dull pain in joint, thigh, or leg
- waddling-type gait may be seen
What is one of the earliest radiographic signs of Legg-Calvé-Perthes disease?
A radiolucent crescent
What does the radiolucent crescent represent?
A collapse of necrotic subchondral bone of the femoral head
Where does the crescent sign typically appear?
Parallel to the superior rim of the femoral head subjacent to the articular surface
Because both OA and AVN are both represented with sclerotic lesions how can you tell the difference between the two?
AVN has normal preservation of radiographic joint space that are not involved in necrotic processes
What is the most appropriate imaging technique to evaluate AVN?
MRI or bone scans
How are patients with AVN treated?
- Prolonged avoidance of weight-bearing
- Traction
- Bracing
- Casting
- Exercise
