The movement seems to be necessary for normal growth of the limbs and joints during intrauterine life. If the fetus stops moving, the joints become stiff. It is then difficult for them to stretch and resume normal movement in utero [7
]. This is the pathogenesis of congenital arthrogryposis. The time point during development at which the limitation of movement begins is probably critical in determining the degree, the type of contractures, and the involvement of other organ systems [3
]. The earlier and longer the duration of decreased movements during fetal development, the more severe the contractures will be. Associated with the lack of fetal movement, extraconnective tissue develops around the joints. This fixes the joint in place, limiting the joint movement and aggravating the contractures [2
]. In our case, according to the decreased fetal movement due to space limitation in uterus, this connective tissue in joints was the more significant histopathological finding, in addition to the edema between muscle fibers in limbs.
Congenital arthrogryposis usually occurs as a sporadic event, but a proportion of cases have a genetic origin involving autosomal dominant, recessive, or X-ligated mechanisms, being a component of a number of genetic syndromes. So it is important to try to determine a specific diagnosis with the objective of establishing the mode of inheritance and risk of recurrence for the purpose of counseling family members and also in following the natural history, which may be quite variable within a family [2
Prenatal ultrasound diagnosis of arthrogryposis is focused on diminished fetal movements and the presence of fixed articular contractures and abnormal positioning of extremities. Nevertheless, these signs are very difficult to detect during the first trimester of pregnancy. For this reason, multiple congenital contractures are usually diagnosed during the second trimester. Ultrasound diagnosis of them is based on observation of scarce or absent fetal movements, which should lead to careful examination of the joints and detection of the anomalies that allow prenatal diagnosis. When the joints of the upper limbs are affected, the shoulders are usually in internal rotation, the forearms are pronated, and there is congenital wrist and radius dislocation with flexion of the hands in a fixed position. If the legs are affected, there may be hip flexion with congenital dislocation. The knee joints may be closed to each other in a hyperextended position and the feet are in varus position. The classical image is that of strongly flexed hands, pes equinovarus and the fetus in a Buddha-like position [8
]. Prenatal ultrasound can also be used to identify associated abnormalities. The lungs are the most frequent site of involvement, besides the limbs. In utero, the fetus has respiratory movements, which are necessary for normal development of the lungs. If the fetus has not moved much, the lungs may be hypoplastic, which is the most common cause of intrauterine and neonatal elevated mortality with congenital contractures [7
Space restriction in uterus, mainly, secondary to oligohydramnios, has been reported as a cause of fetal deformities, but very few cases related to the presence of leiomyomas have been described until now. Leiomyomas of the uterus are detectable in approximately 2% of pregnancies and cause complications in the course of pregnancy or delivery in 1 of 10 diagnosed cases. These complications include premature rupture of membranes, premature birth, placental abruption, necrosis, postpartal hemorrhage, puerperal sepsis, compression on the maternal organs, fetal malpresentation, and increased incidence of abortions and cesarean sections [9
]. Less well known are the potential fetal complications associated with special restriction of the uterine cavity caused by uterine leiomyomas, causing limb reduction, caudal dysplasia, and head deformation and congenital torticollis [10
]. The size and location of the fibroids accompanying a pregnancy have been reported as the most important factors causing these complications. Concerning changes in size during pregnancy, although there are significant differences between scientific papers, some of these papers describe a great increase in volume of myomas during the first trimester of gestation [10
]. Probably this occurred in our case and the previous 47
mm fibroid in anterior uterine wall grow-up quickly during the year before and, specially, in the course of the first trimester of pregnancy protruding into the uterine cavity.
The medical literature generally advocates conservative therapy for leiomyomas during pregnancy. Nevertheless, it is important to be aware of the possibility of complications and to consider myomectomy prior to the gestation because the growth of the leiomyoma cannot be predicted. Even, surgical intervention in pregnant patients should be assessed because, in addition to classical complications, spatial restrictions could have a deleterious effect on human embryos and fetuses.