Fetal Musculoskeletal part 2 Flashcards
Characterized by rhizomelic shortening of the extremities, more prominent in the upper limbs and, a drop off in femur length during second trimester.
Heterozygous Achondroplastic Dwarfism
The most common form of genetic skeletal dysplasia.
Heterozygous Achondroplastic Dwarfism
Heterozygous Achondroplastic Dwarfism and Osteogenesis Imperfecta Types I, III, IV, are all types of __________ skeletal dysplasia’s.
Non-lethal
80 to 90% of Heterozygous Achondroplastic Dwarfism are _________ genetic mutations. Meaning parents do not pass this gene in 80-90% of cases.
Spontaneous
Because of the later manifestation and the occurrence is spontaneous this diagnosis (Heterozygous Achondroplastic Dwarfism) may be missed in the ______ trimester.
second
Sonographic Findings: - Mild to Moderate rhizomelia - Femur length fall short of the expected length for gestational age compared with biparietal diameter, as early as 21 weeks but as late as 27 weeks. - normal femur length prior to 20 weeks - Macrocrania and frontal bossing - Brachydactyly (short digits) This all describes?
Heterozygous Achondroplastic Dwarfism
Occasional fractures, mild limb bowing, easy bruising and blue sclera are some of the clinical features that arise postnatally with what??
Osteogenesis Imperfecta (OI)
These are the non-lethal of OI and have variable outcomes??
Osteogenesis Imperfecta (OI) Types I, III, IV
Which type of Osteogenesis Imperfecta (OI) is the most common?
Type I
Type ___ and type ____ of OI have a good prognosis.
Type I and IV
Type I of OI will also have ________.
deafness
Sonographic findings:
- limb shortening or bowing usually not until after 24 weeks**
- Normal mineralization or occasional demineralization with type I
- Isolated fractures are sometimes present
What Type of OI is this??
Type I and Type IV of OI
Sonographic Findings:
- Moderate to severe micromelia
- Thickened and irregular lower extremity bones because of healing fractures
What type of OI is this??
Type III
This means more than the normal number of digits of the hand or foot. Extra digits may consist of soft tissue only, or may contain bone.
Polydactyly
This is part of fetal akinesia deformation sequence charaterized by multiple joint contractures. All four limbs are typically involved with severity of the deformities increasing distally.
Arthrogryposis
__________ is associated with lack of fetal movement.
***remember this!
Arthrogryposis
Hyperplasia or aplasia of the radius of the forearm is seen in many syndromes. Including Holt Oram syndrome, and Thrombocytopenia (TAR) - absent radius. In addition, trisomy 18 and some exposure conditions will also have radial abnormalities.
Radial Ray Abnormalities
With cases of Radial Ray Abnormalities you will see inward ________ of the hand.
deflection
The permanent curvature or deflection of one or more digits is called?
clinodactyly
The fusion of digits, either soft tissue or bony fusion is called?
syndactyly
This lower extremity abnormality can be genetic or environmental. It is described as an abnormal relationship between the tarsal bones and the calcaneus with different versions.
Clubfoot Deformity
Environmental causes for Clubfoot Deformity include __________ like with oligohydramnios, _________, uterine tumors or uterine duplication.
uterine constraint
amniotic band syndrome
Approximately 55% of clubfoot deformities are _________.
bilateral
Sonographic diagnosis for clubfoor is based upon knowledge of the relative position of the foot and the long bones and often relies on the _________ of the long axis of the _______ and foot in the same plane.
visualization
lower leg
This lower extremity defect can be associated with Trisomy 18 and other anomalies.
Rocker bottom foot
What is Rocker Bottom Foot?
the bottom of the foot looks like a rocker bottom or convex outward.
This is a lower extremity fusion and abnormal or absent foot structures. This can be part of Caudal Regression Syndrome, seen with severe diabetics**.
Sirenomelia or mermaid syndrome
Sonographic Findings:
- Single femur or two femurs constantly side-by-side
- Oligohydramnios
- Abnormal or absent foot structures
- Associated with bilateral renal agenesis
Sirenomelia or Mermaid Syndrome
