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A clinical diagnosis of SCS can be verified by testing the TWIST1 gene (only gene in which mutations are known to cause SCS) for mutations using DNA analysis, such as sequence analysis, deletion/duplication analysis, and cytogenetics/ FISH analysis. Sequence analysis of exon 1 (TWIST1 coding region) provides a good method for detecting the frequency of mutations in the TWIST1 gene. These mutations include nonsense, missense, splice site mutation, and intragenic deletions/insertions. Deletion/duplication analysis identifies mutations in the TWIST1 gene that are not readily detected by sequence analysis. Common methods include PCR, multiplex ligation-dependent probe amplification (MLPA), and chromosomal microarray (CMA). Cytogenetic/FISH analysis attaches fluorescently labels DNA markers to a denatured chromosome and is then examined under fluorescent lighting, which reveals mutations caused by translocations or inversions involving 7p21. Occasionally, individuals with SCS have a chromosome translocation, inversion, or ring chromosome 7 involving 7p21 resulting in atypical findings, such as, increased developmental delay. Individuals with SCS, typically have normal brain functioning and rarely have mental impairments. For this reason, if an individual has both SCS and mental retardation, then they should have their TWIST1 gene screened more carefully because this is not a normal trait of SCS. Cytogenetic testing and direct gene testing can also be used to study gene/chromosome defects. Cytogenetic testing is the study of chromosomes to detect gains or losses of chromosomes or chromosome segments using fluorescent in situ hybridization (FISH) and/or comparative genomic hybridization (CGH). Direct gene testing uses blood, hair, skin, amniotic fluid, or other tissues in order to find genetic disorders. Direct gene testing can determine whether an individual has SCS by testing the individual's blood for mutations in the TWIST1 gene.
Up until recently, experts frequently disagreed on whether a patient had SCS, Crouzon syndrome, isolated craniosynostosis, or some other disease because the symptoms are so closely related, they literally had no way of differentiating between all of them. However, we now have direct gene testing, which allows for a more definitive diagnosis because it allows them to be differentiated from each other based on which gene is mutated in each condition. The following is a list of conditions commonly confused/misdiagnosed for SCS, some of their symptoms, and which mutated gene each contains:
Diagnosis of Crouzon syndrome usually can occur at birth by assessing the signs and symptoms of the baby. Further analysis, including radiographs, magnetic resonance imaging (MRI) scans, genetic testing, X-rays and CT scans can be used to confirm the diagnosis of Crouzon syndrome.
Three main points in diagnosing thumb hypoplasia are: width of the first web space, instability of the involved joints and function of the thumb. Thorough physical examination together with anatomic verification at operation reveals all the anomalies. An X-ray of the hand and thumb in two directions is always mandatory. When the pediatrician thinks the condition is associated with some kind of syndrome other tests will be done. More subtle manifestations of types I and II may not be recognized, especially when more obvious manifestations of longitudinal radial deficiency in the opposite extremity are present. Therefore, a careful examination of both hands is important.
Radiographic analysis by performing a computed axial tomographic scan is the gold standard for diagnosing craniosynostosis.
Plain radiography of the skull may be sufficient for diagnosing a single suture craniosynostosis and should therefore be performed, but the diagnostic value is outweighed by that of the CT-scan. Not only can the sutures be identified more accurately, thus objectively demonstrating a fused suture, but also evaluation of the brain for structural abnormalities and excluding other causes of asymmetric growth are possible at the same time. In addition to this, CT-scanning can visualize the extent of skull deformity, thereby enabling the surgeon to start planning surgical reconstruction.
When it comes to treatment it is important to differentiate a thumb that needs stability, more web width and function, or a thumb that needs to be replaced by the index finger. Severe thumb hypoplasia is best treated by pollicization of the index finger. Less severe thumb hypoplasia can be reconstructed by first web space release, ligament reconstruction and muscle or tendon transfer.
It has been recommended that pollicization is performed before 12 months, but a long-term study of pollicizations performed between the age of 9 months and 16 years showed no differences in function related to age at operation.
It is important to know that every reconstruction of the thumb never gives a normal thumb, because there is always a decline of function. When a child has a good index finger, wrist and fore-arm the maximum strength of the thumb will be 50% after surgery in comparison with a normal thumb. The less developed the index finger, wrist and fore-arm is, the less strength the reconstructed thumb will have after surgery.
Evaluations by certain specialists should be performed following the initial diagnosis of Duane-radial ray syndrome. These evaluations will be used to determine the extent of the disease as well as the needs of the individual.
- Eyes - Complete eye exam by an ophthalmologist especially focusing on the extraocular movements of the eye and the structural eye defects
- Heart - evaluation by a cardiologist along with an echocardiogram and ECG
- Kidneys - Laboratory tests to check kidney function and a renal ultrasound
- Hearing
- Endocrine - evaluation for growth hormone deficit if growth retardation present
- Blood - CBC to check for thrombocytopenia and leukocytosis
- Clinical genetics consultation
MRI imaging can be used to detect whether the abducens nerve is present.
Each child is different and it entirely depends on which sutures are fused and how it is affecting the child as to how it is treated. Some children have severe breathing issues due to shallow mid face and may require a tracheostomy. All should be treated at a specialist centre. Cranio bands are not used in the UK.
Surgery is typically used to prevent the closure of sutures of the skull from damaging the brain's development. Without surgery, blindness and mental retardation are typical outcomes. Craniofacial surgery is a discipline of both plastic surgery and oral and maxillofacial surgery (OMFS) . To move the orbits forward, craniofacial surgeons expose the skull and orbits and reshape the bone. To treat the midface deficiency, craniofacial surgeons can move the lower orbit and midface bones forward. For jaw surgery, either plastic surgeons or OMFS surgeons can perform these operations.
Crouzon patients tend to have multiple sutures involved, most specifically bilateral coronal craniosynostoses, and either open vault surgery or strip craniectomy (if child is under 6 months) can be performed. In the later scenario, a helmet is worn for several months following surgery.
Once treated for the cranial vault symptoms, Crouzon patients generally go on to live a normal lifespan.
There is no standard treatment for the hand malformations in Apert due to the differences and severity in clinical manifestations in different patients. Every patient should therefore be individually approached and treated, aiming at an adequate balance between hand functionality and aesthetics.
However, some guidelines can be given depending on the severity of the deformities.
In general it is initially recommended to release the first and fourth interdigital spaces, thus releasing the border rays.
This makes it possible for the child to grasp things by hand, a very important function for the child's development. Later the second and third interdigital spaces have to be released.
Because there are three handtypes in Apert, all with their own deformities, they all need a different approach regarding their treatment:
- Type I hand usually needs only the interdigital web space release. First web release is rarely needed but often its deepening is necessary. Thumb clynodactyly correction will be needed.
- In type II hands it is recommended to release the first and fifth rays in the beginning, then the second and the third interdigital web spaces have to be freed. The clynodactyly of the thumb has to be corrected as well. The lengthening of the thumb phalanx may be needed, thus increasing the first web space. In both type I and type II, the recurrent syndactyly of the second web space will occur because of a pseudoepiphysis at the base of the index metacarpal. This should be corrected by later revisions.
- Type III hands are the most challenging to treat because of their complexity. First of all, it is advised to release the first and fourth webspace, thus converting it to type I hand. The treatment of macerations and nail-bed infections should also be done in the beginning. For increasing of the first web space, lengthening of the thumb can be done. It is suggested that in severe cases an amputation of the index finger should be considered. However, before making this decision, it is important to weigh the potential improvement to be achieved against the possible psychological problems of the child later due to the aesthetics of the hand. Later, the second and/or third interdigital web space should be released.
With growing of a child and respectively the hands, secondary revisions are needed to treat the contractures and to improve the aesthetics.
The treatment of pansynostosis comprises the expansion of the anterior cranial vault, as well as the posterior cranial vault. This can be accomplished in one procedure, but is generally performed in two.
Because neither of the two thumb components is normal, a decision should be taken on combining which elements to create the best possible composite digit. Instead of amputating the most hypoplastic thumb, preservation of skin, nail, collateral ligaments and tendons is needed to augment the residual thumb. Surgery is recommended in the first year of life, generally between 9 and 15 months of age.
Surgical options depend on type of polydactyly.
In this situation there is an absence of osseous and ligamentous structures. The surgical technique is analogous to radial polydactyly, in which the level of duplication and anatomical components should guide operative treatment.
The pedicled ulnar extra digit can be removed by suture ligation to devise the skin bridge of the newborn child. This might be easier than an excision of the extra digit when the child is 6 to 12 months old. Ligation occludes the vascular supply to the duplicated digit, resulting in dry gangrene and subsequent autoamputation. This must be done with consideration of the presence of a neurovascular bundle, even in very small skin bridges. When the ligation is done inappropriately it can give a residual nubbin. Also, a neuroma can develop in the area of the scar. An excision can prevent the development of a residual nubbin and the sensibility due to a neuroma.
For infants with ulnar type B polydactyly the recommended treatment is ligation in the neonatal nursery. Studies have shown that excision of the extra digit in the neonatal nursery is a safe and simple procedure with a good clinical and cosmetic outcome.
There are multiple classifications for the triphalangeal thumb. The reason for these different classifications is the heterogeneity in appearance of the TPT.
The classification according to Wood describes the shape of the extra phalanx: delta (Fig. 4), rectangular or full phalanx (Table 1). With the classification made by Buck-Gramcko a surgical treatment can be chosen (Table 1). Buck-Gramcko differentiates between six different shapes of the extra phalanx and associated malformations.
Table 1: Classifications of Wood and Buck-Gramcko
Omphalocele has been described in two patients with Apert syndrome by Herman T.E. et al. (USA, 2010) and by Ercoli G. et al. (Argentina, 2014). An omphalocele is a birth defect in which an intestine or other abdominal organs are outside of the body of an infant because of a hole in the bellybutton area. However, the association between omphalocele and Apert syndrome is not confirmed yet, so additional studies are necessary.
Patients with abnormal cardiac and kidney function may be more at risk for hemolytic uremic syndrome
Diagnosis is based on physical examination including radiographs of the hands and feet and imaging studies of the kidneys, bladder, and female reproductive tract. HOXA13 is the only gene known to be associated with HFGS. Approximately 60% of mutations are polyalanine expansions. Molecular genetic testing is clinically available.
The goals of surgical treatment are: reducing length of the thumb, creating a good functioning, a stable and non deviated joint and improving the position of the thumb if necessary. Hereby improving function of the hand and thumb.
In general the surgical treatment is done for improvement of the thumb function. However, an extra advantage of the surgery is the improvement in appearance of the thumb. In the past, surgical treatment of the triphalangeal thumb was not indicated, but now it is generally agreed that operative treatment improves function and appearance. Because an operation was not indicated in the past, there’s still a population with an untreated triphalangeal thumb. The majority of this population doesn’t want surgery, because the daily functioning of the hand is good. The main obstacle for the untreated patients might not be the diminished function, but the appearance of the triphalangeal thumb.
The timing of surgery differs between Wood and Buck-Gramcko. Wood advises operation between the age of six months and two years, while Buck-Gramcko advises to operate for all indications before the age of six years.
- For TPT types I and II of the Buck-Gramcko classification, the surgical treatment typically consists of removing the extra phalanx and reconstructing the ulnar collateral ligament and the radial collateral ligament if necessary.
- For type III of Buck-Gramcko classification proposable surgical treatments:
- For type IV of Buck-Gramcko classification the surgical treatment typically consists of an osteotomy which reduces the middle phalanx and arthrodesis of the DIP. This gives a shortening of 1 to 1.5 cm. In most cases, this technique is combined with a shortening, rotation and palmar abduction osteotomy at metacarpal level to correct for position and length of the thumb. The extensor tendons and the intrinsic muscles are shortened as well.
- For type V of the Buck-Gramcko classification the surgical treatment proposably consists of a "pollicization". With a pollicization the malpositioned thumb is repositioned, rotated and shortened, the above-described rotation reduction osteotomy of the first metacarpal can be performed as well.
- For type VI of the Buck-Gramcko classification, the surgical treatment typically consists of removing the additional mostly hypoplastic thumb(s). Further procedures of reconstruction of the triphalangeal thumb are performed according to the shape of the extra phalanx as described above.
Additional findings that may be present in HFGS according to the latest research are:
- Limited metacarpophalangeal flexion of the thumb or limited ability to oppose the thumb and fifth finger
- Hypoplastic thenar eminences
- Medial deviation of the great toe (hallux varus), a useful diagnostic sign when present
- Small great toenail
- Fifth-finger clinodactyly, secondary to a shortened middle phalanx
- Short feet
- Altered dermatoglyphics of the hands; when present, primarily involving distal placement of the axial triradius, lack of thenar or hypothenar patterning, low arches on the thumbs, thin ulnar loops (deficiency of radial loops and whorls), and a greatly reduced ridge count on the fingers
Radiographic findings
- Hypoplasia of the distal phalanx and first metacarpal of the thumbs and great toes
- Pointed distal phalanges of the thumb
- Lack of normal tufting of the distal phalanges of the great toes
- Fusions of the cuneiform to other tarsal bones or trapezium-scaphoid fusion of the carpals
- Short calcaneus
- Occasional bony fusions of the middle and distal phalanges of the second, third, fourth, or fifth toes
- Delayed carpal or tarsal maturation
- Metacarpophalangeal profile reflecting shortening of the first metacarpal, the first and second phalanges, and the second phalanx of the second and fifth digits
Urogenital Defects
Females may have the following:
- Vesicoureteral reflux secondary to ureteric incompetence
- Ectopic ureteral orifices
- Trigonal hypoplasia
- Hypospadiac urethra
- Subsymphyseal epispadias
- Patulous urethra
- Urinary incontinence (related to structural anomalies and weakness of the bladder sphincter muscle)
- Small hymenal opening
- Various degrees of incomplete Müllerian fusion with or without two cervices or a longitudinal vaginal septum
Males may have the following:
- Retrograde ejaculation (related to structural anomalies and weakness of the bladder sphincter muscle)
There are four levels (or "types") of malformation. The least severe indicates partial deformation (unilateral) of the sacrum. The second level indicates a bilateral (uniform) deformation. The most severe types involve a total absence of the sacrum.
Depending on the type of sacral agenesis, bowel or urinary bladder deficiencies may be present. A permanent colostomy may be necessary in the case of imperforate anus. Incontinence may also require some type of continence control system (e.g., self-catheterization) be utilized. Occasionally if deformities of the knees, legs or feet would prove unresponsive to corrective action, amputation at the knee may be proposed.
Before more comprehensive medical treatment was available, full amputation of the legs at the hip was often performed. More recently, the 'amputation' (actually a disarticulation because no cutting of the bone is involved) is done at the knee for those who have bent knee positions and webbing between thigh and calf to enable more ease of mobility and better seating. Some children with knee disarticulation use prosthetic legs to walk. Prosthetics for children without substantial hip and trunk control is usually abandoned in favor of faster and easier wheelchair mobility as the child's weight and age increases. Children may 'walk' on their hands and generally are able to climb and move about to accomplish whatever they need and want to accomplish. Children more mildly affected may have normal gait and no need for assistive devices for walking. Others may walk with bracing or crutches.
There is typically no cognitive impairment associated with this disability. Adults with this disability live independently, attend college, and have careers in various fields. In 2012, Spencer West, a man with sacral agenesis and both legs amputated, climbed Mt. Kilimanjaro using only his hands.
While there is no cure for BGS, symptoms can be treated as they arise. Surgery shortly after birth can repair craniosynostosis, as well as defects in the hand to create a functional grasp. There are risks associated with untreated craniosynostosis, therefore surgery is often needed to separate and reshape the bones. Since patients with a RECQL4 mutation may be at an increased risk of developing cancer, surveillance is recommended.
The diagnosis depends on appropriate patient history backed by imaging studies like X ray and MRI. Lumbosacral spine radiographs help in the identification of the skeletal abnormality. MRI helps in confirmation.
The incidence of VACTERL association is estimated to be approximately 1 in 10,000 to 1 in 40,000 live-born infants. It is seen more frequently in infants born to diabetic mothers. While most cases are sporadic, there are clearly families who present with multiple involved members.
Males are twice as likely as females to have this characteristic, and it tends to run in families. In its non-symptomatic form, it is more common among Asians and Native Americans than among other populations, and in some families there is a tendency to inherit the condition unilaterally, that is, on one hand only.
The presence of a single transverse palmar crease can be, but is not always, a symptom associated with abnormal medical conditions, such as fetal alcohol syndrome, or with genetic chromosomal abnormalities, including Down Syndrome (chromosome 21), cri du chat syndrome (chromosome 5), Klinefelter syndrome, Wolf-Hirschhorn Syndrome, Noonan syndrome (chromosome 12), Patau syndrome (chromosome 13), IDIC 15/Dup15q (chromosome 15), Edward's syndrome (chromosome 18), and Aarskog-Scott syndrome (X-linked recessive), or autosomal recessive disorder, such as Leaukocyte adhesion deficiency-2 (LAD2). A unilateral single palmar crease was also reported in a case of chromosome 9 mutation causing Nevoid basal cell carcinoma syndrome and Robinow syndrome. It is also sometimes found on the hand of the affected side of patients with Poland Syndrome, and craniosynostosis.
Schmitt Gillenwater Kelly syndrome is a rare autosomal dominant congenital disorder consisting of radial hypoplasia, triphalangeal thumbs, hypospadias, and maxillary diastema.