Figure 2: A different fetus with abnormal and rigid position of the knee. The distance between the knee is less than that between the hips. Also note that both feet are inverted.
Genetic anomalies: Several anomalies have been linked to the following site 5q35, 9p21-q21, 11p15.5.
Differential diagnosis: Trisomy 18, renal agenesis and myotonic dystrophy may present with some similar findings.
Associated anomalies: Because of the heterogeneity of the conditions numerous associated anomalies have been described including scoliosis, CNS anomalies even seizures.
Prognosis: The prognosis will depend on associated anomalies (respiratory limitations, scoliosis.)
Management: Termination of pregnancy can be offered before viability. Standard prenatal care is not altered when continuation the pregnancy is opted for. Confirmation of diagnosis after birth is important for genetic counseling.
References:
[1] Lammens M, Moerman P, Fryns JP, Lemmens F, van de Kamp GM, Goemans N, Dom R Fetal akinesia sequence caused by nemaline myopathy. Neuropediatrics 1997 Apr;28(2):116-9
[2] Hyett J, Noble P, Sebire NJ, Snijders R, Nicolaides KH Lethal congenital arthrogryposis presents with increased nuchal translucency at 10-14 weeks of gestation. Ultrasound Obstet Gynecol 1997 May;9(5):310-3
[3] Ajayi RA, Keen CE, Knott PD: Ultrasound diagnosis of the Pena Shokeir phenotype at 14 weeks of pregnancy. Prenat Diagn 1995 Aug;15(8):762-4
[4] Skupski DW, Sepulveda W, Udom-Rice I, Leo MV, Lescale KB, Chervenak FA: Fetal seizures: further observations. Obstet Gynecol 1996 Oct;88(4 Pt 2):663-5