PEDIATRIC Section 13: MSK (Hip Dysplasia) Flashcards
Developmental Dysplasia of the Hip (DDH)
asymmetric skin or gluteal folds
leg length discrepancy
palpable clunk
delayed ambulation.
Developmental Dysplasia of the Hip (DDH)
This is seen more commonly in females, children bom breech, and oligohydramnios.
Developmental Dysplasia of the Hip (DDH) on USD
On ultrasound the alpha angle, should be more than 60 degrees.
Anything less than that and your cup is not deep enough to hold your ball.
“AlphaAngleistheAlphaMale”- and therefore the bigger of the two angles.
Developmental Dysplasia of the Hip (DDH) on CXR
acetabular angle, which is the complimentary angle (and therefore should be less than 30).
The acetabular angle should decrease from 30 degrees at birth to 22 degrees at age 1. DDH is the classic cause of an increased angle, but neuromuscular disorder can also increase it.
Where the the position of the femoral epiphysis (or where it will be) should be
Below the Hilgenreiner’s line
Medial to Perkin’s line
Shenton’s line “S” Shoud be continusous
This is a congenital zebra, which ranges from absent proximal femur to hypoplastic proximal femur.
Proximal Focal Femoral Deficiency:
“weird fucked up looking tiny Frankenstein leg. “
+ varus devormity
Proximal Focal Femoral Deficiency:
This is described as a mimic of DDH
Proximal Focal Femoral Deficiency
Proximal Focal Femoral Deficiency vs DDH (Developmental Dysplasia of the HIP)
This is described as a mimic of DDH,
but DDH will have normal femur leg length (not a fucked up looking tiny Frankenstein leg).
fat African American adolescent (age 12-15) with hip pain.
This is a type 1 Salter Harris, through the proximal femoral physis. What makes this unique is that unlike most SH Is, this guy has a bad prognosis if not fixed.
Slipped Capital Femoral Epiphysis (SCFE)
wht View on Xray should be done after suspecting Slipped Capital Femoral Epiphysis (SCFE)
Drawn along the edge of the femur and should normally intersect with lateral superior femoral epiphysis. This line is used to evaluate for SCFE (Slipped Capital Femoral Epiphysis)
“Klein’s Line”
When the line doesn’t cross the lateral epiphysis think SCFE.
View on Xray more sensitive when measurement “Klein’s Line”
Frog leg
This is AVN of the proximal femoral epiphysis.
Legg-Calve-Perthes
Where is Legg-Calve-Perthes seen?
Boys (4:1)
5-8 y.o
Bilateral 10% of the time
Subchondral lucency (crescent sign) in the femoral epyhysis seen on frog leg
Legg-Calve-Perthes
Legg-Calve-Perthes
flat collapsed femoral head
This is serious business , and considered the most urgent cause of painful
hip in a child.
Septic arthritis
What should prompt USD and Joint tap in a child with painflul hip?
Wide joint spaces (Lateral displacement of the femoral head)
This is a sterile (reactive) hip effusion that occurs in the setting of
a systemic illness (usually viral URI or GI).
Transient Synovitis
Mot common hip disorder in growing child (peak age is around 5)
Transient Synovitis
What is the Kocher Criteria?
4 parts:
Ferver
Inability to walk
Elevated ESR (or CRP)
WBC > 12k
If 3/4 + = Septic
IF (-) CRP + the kid can bear weight = NOT septic
What is the strongest independent risk factor for septic arthritis?
CRP
Work up fo Transient Synovitis vs Septic Arthritis?
Medial joint widening on Xray + Effusion on USD + (>2) Kocher criteria score + MRI when hip aspiration hasn’t been performed
