A case of congenital familial short femur diagnosed prenatally

Isolated unilateral proximal focal femoral deficiency presenting in a young woman

Proximal focal femoral deficiency (PFFD) is a rare congenital skeletal abnormality characterised by the partial absence of the proximal femoral segment with shortening of the entire lower extremity. It typically presents as a shortened thigh, which is flexed, externally rotated and abducted. Some other skeletal anomalies, especially fibular hemimelia, usually accompany the disorder. The diagnosis of PFFD is made in early childhood and based mainly on conventional radiography. However, the radiographic appearance of the disease evolves as the child grows. In addition, treatment procedures applied to the child affect the radiographic presentation of the disease in adulthood. Almost all cases of PFFD reported to date are in young children and in the current literature, there is a paucity of radiographic images of PFFD in mature skeleton. The aim of this case report is to present the radiographic appearance of PFFD in an adult patient and to increase awareness among radiologists about this disease.

Unilateral isolated proximal femoral focal deficiency

Objective. To discuss a patient with a prenatal diagnosis of unilateral isolated femoral focal deficiency. Case. Antenatal diagnosis of unilateral isolated femoral focal deficiency was made at 20 weeks of gestation. The length of left femur was shorter than the right, and fetal femur length was below the fifth percentile. Proximal femoral focal deficiency was diagnosed. After delivery, the diagnosis was confirmed with skeletal radiographs and magnetic resonance imaging. In prenatal ultrasonographic examination, the early recognition and exclusion of skeletal dysplasias is important; moreover, treatment plans should be initiated, and valuable information should be provided to the family.

Outcome of fetuses with diagnosis of isolated short femur in the second half of pregnancy

Objectives. To assess the outcome of fetuses with isolated short femur detected at 19-41 weeks and determine to what extent this incidental finding should be a cause of concern in fetuses with a normal previous follow-up. Methods. 156 fetuses with isolated short femur were compared with a control group of 637 fetuses with normal femur length. FL values were converted into Z-scores and classified into 4 groups: control group: Z-score over -2, group 1: Z-score between -2 and -3, group 2: Z-score between -3 and -4, and group 3: Z-score below -4. FL values were plotted with the curves representing Z-scores -2, -3, and -4. To assess fetal outcome, the frequency of SGA, IUGR, abnormal umbilical Doppler (AUD), Down's syndrome, and skeletal dysplasia was determined for each group after delivery, and the relative risk in comparison with the control group was obtained. Finally, ROC curves were drawn in order to evaluate the FL diagnostic ability for the conditions appearing with increased frequency. Results. SGA, IUGR, and AUD were more frequent in the fetuses with short femur. Conversely, none of them presented Down's syndrome or skeletal dysplasia. According to ROC analysis, FL measurement behaved as a good diagnostic test for SGA and IUGR. Conclusions. A short femur diagnosis in a fetus with an otherwise normal follow-up determines just a higher risk of being small (SGA or IUGR).

Prenatal diagnosis of musculoskeletal anomalies

Musculoskeletal anomalies are not uncommon in prenatal life. They can be either sporadic or part of chromosomal syndromes causing prenatal morbidity and mortality. The prenatal diagnosis of musculoskeletal anomalies is based on information assembled from various imaging modalities and from biochemical and genetic workups. The prenatal diagnosis can serve as a prognostic tool and in counseling the parents. Among the imaging methods, ultrasonography is the most popular and cost effective in observing and following fetal development from the very early stages of gestation. Transvaginal sonography can detect and identify most of the normal and the specific pathologic changes very close to the stage of their embryogenic development. From a practical point of view, early detailed transvaginal sonography screening at 14 to 15 weeks of gestation is very useful while late detection at 20 to 23 weeks of gestation may provide some additional information in low-risk pregnancies. Very early screening, even during the ninth week, may be indicated in high-risk pregnancies. Additional genetic counseling is recommended when abnormal findings are suspected. We summarize the diagnostic approach and the information available for the most common musculoskeletal anomalies.