Overview

Femoral Facies Syndrome (FFS), also known as Femoral hypoplasia-unusual facies syndrome, isn’t a term you hear very often, However, a few significant groups of physical features are associated with this syndrome, hence, it must be identified quickly to come up with an effective treatment plan.¹

What is femoral facies syndrome?

It is an uncommon congenital syndrome, characterised by a collection of anatomical differences from normal bone structure. The name itself provides insight into the condition:

• "Femoral" refers to the thigh bone (femur).
• "Facies" relates to distinctive facial features or expressions.

FFS is classified as a congenital musculoskeletal disorder. The definite causative factor hasn’t been determined yet, but there is a noted correlation with maternal diabetes in a third of the cases.²

Most cases have been noted to be random (sporadic), meaning there is no specific genetic, demographic, or clinical relation to infants diagnosed with FFS. It has been observed that more persons assigned male at birth (AMAB) are affected in comparison to persons assigned female at birth (AFAB). There is still a lot of research to be done concerning whether there is a specific genetic component.

Only having a record of just over 70 cases since 1975, when it was first described, the characteristic features that should be noted are the anomalies in the thigh bone, mostly underdeveloped bilaterally, and facial structure. This condition is particularly interesting because it draws similarities to other conditions in children such as Pierre Robin Syndrome, Camptomelic syndrome, and Caudal regression syndrome.³ Other organs and organ systems, the central nervous system, reproductive system, and cardiovascular system, have shown multiple differences as well.

There isn’t a lot of literature on people living with this syndrome, and because of this, the life expectancy associated with FFS is unknown as well. This could be due to a plethora of reasons, the more common ones being misdiagnosis or late diagnosis. Most cases, unfortunately, report that the cause of death is termination during pregnancy or death shortly after birth, which reaffirms the need to diagnose it early on.

Physical characteristics of femoral facies syndrome

As aforementioned, the most notable physical characteristics are bilateral underdeveloped thigh bones and atypical facial structure.⁴

The common thigh bone (femoral) irregularities associated with FFS are:

• Thigh bone (femur) absent or anatomically abnormal
• Dwarfed limbs, especially the lower limb (micromelia)
• Thigh bone neck anomaly (Coxa vara)

The common facial irregularities associated with FFS are:

• Smaller or retracted jaw (micrognathia/retrognathia)
• Gap or split in the upper lip and/or roof of the mouth (cleft palate)
• Upward slanting of the space between the eyelids (Up-slanting palpebral fissures)
• Short nose
• Thinner lips
• Elongated groove in the middle of the upper lip (long philtrum)
• Low-set and poorly-formed ears or absence of ears (microtia/anotia)

Other anatomical anomalies associated with Femoral Facies syndrome-

• Congenital hip dislocation (hip dysplasia)
• Abnormal spinal bone structure (vertebral deformities)
• Extra toes (preaxial foot polydactyly)
• Foot pointing downward and inward, clubfoot (talipes equinovarus)
• Short stature (dwarfism)

According to research, there are a myriad of other noted physical attributes, but these are the most commonly observed.

How is femoral facies syndrome diagnosed?

The conclusion of FFS is mostly clinical, meaning that the baby's physical characteristics usually help determine the diagnosis.  It is possible to detect the syndrome during ultrasound screenings and check-ups, however, the number of cases detected “in utero” has been very few.⁵ It is because this is a collection of signs that accumulate to form FFS but are also presentations found in other pediatric conditions, making it very difficult to form a concrete diagnosis until birth or, regrettably, in autopsies.

Usually, if one long bone or skull bone deformity is noticed during prenatal assessments, it is dwelled with more scrutiny but so far only a few cases in that circumstance have been reported.⁶

Treatment options for femoral facies syndrome

There isn’t a standard practice for FFS because it is so uncommon; the treatment is usually case-based and approached by a group of specialist doctors like paediatricians, dental specialists, surgeons, speech therapists, and others. These specialists will determine the best course of action, and there will be steps put in place for long-term care and monitoring for any deficiency, physical or otherwise.

There will be an orthopaedic approach to the patient in hopes of correcting the anatomical problem. This includes the use of orthotic devices, such as specialised boots, braces, limb-correcting devices, and long-term physiotherapy.  Genetic counselling and supportive treatment will also be offered.

There is a dire need for more research into FFS to help patients and families understand the condition better. With the advancement of science, it is safe to assume that advancement in genetic research is on its way. This opens up possibilities for genetic therapies and understanding gene-environment interactions better. The future of surgery looks towards minimally invasive surgical techniques and innovation that support speedier recovery and better outcomes for patients. This also opens doors for potentially improved prosthetic and orthotic designs, allowing a better and longer quality of life for those affected.

Summary

Femoral Facies Syndrome, though rare, presents with distinct physical anomalies requiring early and accurate diagnosis. The syndrome's complexity and overlap with other conditions pose significant diagnostic challenges. Multidisciplinary approaches and continued research are essential for improving patient care and outcomes.