Prenatal diagnosis of congenital femoral deficiency and fibular hemimelia

Prenatal diagnosis of tibial hemimelia type I and omphalocele, a rare entity and postnatal correlation

Hemimelia is a rare anomaly affecting the distal long bones of extremities, with an occurrence of 1–20 cases per million of live births depending on the affected bone. Hemimelia can be an isolated defect or be part of complex syndromes that affect extra skeletal structures. Prenatal detection by routine ultrasound imaging is difficult and yields low detection rates. The prenatal diagnosis of hemimelia should prompt a complete and detailed study of the fetal anatomy, since it can be associated with defects in other structures and systems, as the reported in this case. The prognosis depends upon the associated anomalies.

Support, information, and integration of genetics for children with congenital lower limb deficiencies in British Columbia, Canada

Objectives

Children and families affected by congenital limb deficiencies (CLD) require a unique level of emotional support from diagnosis through to adolescence. The following study aims to collect data on Canadian paediatric patients affected by a CLD followed at BC Children's Hospital (BCCH), Department of Orthopaedics.

Methods

Parents of children with a CLD were asked to complete a written questionnaire examining their experiences. Qualitative and quantitative data were collected concerning parent satisfaction with patient referrals, emotional support, and knowledge of their child's diagnosis.

Results

Twenty-five completed questionnaires were returned. Fifty per cent of the parents reported they were either very satisfied, or satisfied, with the emotional support provided by health care providers (HCPs). Twenty-five per cent of the parents were unsatisfied with the emotional support received by HCPs. Forty-eight per cent of the parents could not recall the specific name of their child's diagnosis; 20% of the parents reported their child did not have diagnosis. All the patients in our study had received a clinical diagnosis. Twenty-eight per cent of the parents in this study were also seen in medical genetics.

Conclusions

Families require additional resources for emotional support, peer support, and referrals to support organizations. Gaps in parent knowledge regarding their child's CLD suggest the need for formalized communication strategies for HCPs. Furthermore, patients with CLDs and their families may benefit from improved communication between orthopaedic and medical genetic services at the time of diagnosis. Integration of genetic counsellors may improve emotional supports and education for families with regards to testing and reproductive planning.

Constant inhibition in congenital lower extremity shortening: does it begin in utero?

BACKGROUND

Limb-length discrepancy (LLD) in children with congenital lower extremity shortening is constant in proportion from birth to skeletal maturity (known as constant inhibition), but its developmental pattern in utero is unknown. The popular prenatal multiplier method to predict LLD at birth assumes constant inhibition in utero to be true. Verifying the in utero developmental pattern of LLD, and thus confirming the validity of the prenatal multiplier method, is crucial for meaningful prenatal parental counseling.

OBJECTIVE

To elucidate the in utero developmental pattern of LLD in fetuses with congenital lower extremity shortening.

MATERIALS AND METHODS

Clinical indications for 3,605 lower extremity radiographs performed on infants (<1 year old) at a large tertiary hospital over a 17-year period were reviewed. Inclusion criteria were (1) diagnosis of congenital lower extremity shortening, (2) bilateral lower limb postnatal radiographs documenting LLD and (3) fetal ultrasound (US) documenting LLD. Available measurements of femoral, tibial and fibular lengths on fetal US and postnatal radiographs were collected. Prenatal and postnatal length ratios of shorter-to-longer bones were calculated and compared.

RESULTS

Eighteen infants met inclusion criteria. Diagnoses were proximal focal femoral deficiency=4, congenital short femur=2, tibial hemimelia=3, posteromedial tibial bowing=6 and fibular hemimelia=3. The correlations between postnatal and prenatal length ratios were high for the femur, tibia and fibula (R>0.98, P<0.0001). The relative differences in the postnatal and prenatal length ratios of these bones were small (|average|<0.026, standard deviation <0.068).

CONCLUSION

Our data indicate that the postnatal and prenatal length ratios were equivalent, supporting the constant inhibition pattern of LLD in utero, thus validating the prenatal multiplier method for predicting LLD.