Biomechanical properties of the patellar tendon in children with heritable connective tissue disorders.

PURPOSE: Hereditary connective tissue disorders (HCTDs), such as classic Ehlers-Danlos syndrome (cEDS) and Marfan syndrome (MS) share overlapping features like hypermobility and tissue fragility. In clinical practice it remains a challenge to distinguish children and adolescents with HCTD from healthy children. The purpose of this study was to investigate the biomechanical properties of the patellar tendon and joint laxity (Beighton score) in children with HCTDs (n = 7) compared to healthy controls (n = 14). METHODS: The mechanical properties of the patellar tendon were assessed using simultaneous force and ultrasonographic measurements during isometric ramp contractions. Ultrasonography was also used to measure tendon dimensions. The HCTD children were matched with 2 healthy controls with regard to age, body mass index (BMI), sex and physical activity level. RESULTS: The HCTD children had a greater degree of joint laxity (P < 0.01). Although, the patellar tendon dimensions did not differ significantly between the two groups, the HCTD children showed a tendency toward a larger patellar tendon cross-sectional area (CSA) (35%, P = 0.19). Moreover, stiffness did not differ between the two groups, but secant modulus was 27% lower in children with a HCTD (P = 0.05) at common force and 34% lower at maximum force (P = 0.02). CONCLUSIONS: The present study demonstrates for the first time that children with HCTDs have lower material properties (modulus) of their patellar tendon, which may be indicative of general impairment of connective tissue mechanics related to their increased joint laxity.

Facial Asymmetry in Children with Unicoronal Synostosis Who Have Undergone Craniofacial Reconstruction in Infancy.

OBJECTIVE: Quantitatively assess 3D spatially detailed soft-tissue facial asymmetry in children who had undergone craniofacial reconstruction for Unicoronal Synostosis (UCS), and compare the facial asymmetry to control patients. It was hypothesized that there would be no significant differences in the facial asymmetry between the groups. DESIGN: Clinical, retrospective follow-up study. Methodological study. SETTING: Primary care center. PATIENTS/PARTICIPANTS: Twenty-two children with UCS were selected after review of records. INCLUSION CRITERIA: isolated UCS; surgically treated for UCS within the first 19 months of life, without secondary reconstruction; and DNA analysis for the Muenke mutation. An age- and sex-matched control group was employed. INTERVENTIONS: The UCS group had undergone bilateral craniotomy of the frontal bone with unilateral supraorbital rim advancement. MAIN OUTCOME MEASURE(S): Using 3D surface scanning, a detailed map of 3D asymmetry presenting the amount of asymmetry in the sagittal, vertical, and transverse directions was calculated for six facial subregions. RESULTS: The facial asymmetry in the UCS group was significantly larger than in the control group for all regions, to the largest extent in the sagittal direction (level of significance: 5%). The regions with the most pronounced asymmetry were cheeks (mean: 5.45 mm; SD: 1.83 mm), forehead (mean: 5.00 mm; SD: 1.57 mm), and eyes (mean: 4.26 mm; SD: 1.44 mm). CONCLUSIONS: Ninety percent of the UCS patients in the study had significant facial asymmetry throughout the facial area. The study demonstrates a methodology of facial asymmetry quantification well suited for soft-tissue surgical outcome evaluations and long-term follow-up studies in patients with craniofacial anomalies.

A study of the clinical and radiological features in a cohort of 93 patients with a COL2A1 mutation causing spondyloepiphyseal dysplasia congenita or a related phenotype.

Type 2 collagen disorders encompass a diverse group of skeletal dysplasias that are commonly associated with orthopedic, ocular, and hearing problems. However, the frequency of many clinical features has never been determined. We retrospectively investigated the clinical, radiological, and genotypic data in a group of 93 patients with molecularly confirmed SEDC or a related disorder. The majority of the patients (80/93) had short stature, with radiological features of SEDC (n = 64), others having SEMD (n = 5), Kniest dysplasia (n = 7), spondyloperipheral dysplasia (n = 2), or Torrance-like dysplasia (n = 2). The remaining 13 patients had normal stature with mild SED, Stickler-like syndrome or multiple epiphyseal dysplasia. Over 50% of the patients had undergone orthopedic surgery, usually for scoliosis, femoral osteotomy or hip replacement. Odontoid hypoplasia was present in 56% (95% CI 38-74) and a correlation between odontoid hypoplasia and short stature was observed. Atlanto-axial instability, was observed in 5 of the 18 patients (28%, 95% CI 10-54) in whom flexion-extension films of the cervical spine were available; however, it was rarely accompanied by myelopathy. Myopia was found in 45% (95% CI 35-56), and retinal detachment had occurred in 12% (95% CI 6-21; median age 14 years; youngest age 3.5 years). Thirty-two patients complained of hearing loss (37%, 95% CI 27-48) of whom 17 required hearing aids. The ophthalmological features and possibly also hearing loss are often relatively frequent and severe in patients with splicing mutations. Based on clinical findings, age at onset and genotype-phenotype correlations in this cohort, we propose guidelines for the management and follow-up in this group of disorders.

The cardiac phenotype in patients with a CHD7 mutation.

BACKGROUND: Loss-of-function mutations in CHD7 cause Coloboma, Heart Disease, Atresia of Choanae, Retardation of Growth and/or Development, Genital Hypoplasia, and Ear Abnormalities With or Without Deafness (CHARGE) syndrome, a variable combination of multiple congenital malformations including heart defects. Heart defects are reported in 70% to 92% of patients with a CHD7 mutation, but most studies are small and do not provide a detailed classification of the defects. We present the first, detailed, descriptive study on the cardiac phenotype of 299 patients with a CHD7 mutation and discuss the role of CHD7 in cardiac development. METHODS AND RESULTS: We collected information on congenital heart defects in 299 patients with a pathogenic CHD7 mutation, of whom 220 (74%) had a congenital heart defect. Detailed information on the heart defects was available for 202 of these patients. We classified the heart defects based on embryonic cardiac development and compared the distribution to 1007 equally classified nonsyndromic heart defects of patients registered by EUROCAT, a European Registry of Congenital Anomalies. Heart defects are highly variable in patients with CHD7 mutations, but atrioventricular septal defects and conotruncal heart defects are over-represented. Sex did not have an effect on the presence of heart defects, but truncating CHD7 mutations resulted in a heart defect significantly more often than missense or splice-site mutations (χ², P<0.001). CONCLUSIONS: CHD7 plays an important role in cardiac development, given that we found a wide range of heart defects in 74% of a large cohort of patients with a CHD7 mutation. Conotruncal defects and atrioventricular septal defects are over-represented in patients with CHD7 mutations compared with patients with nonsyndromic heart defects.

Microdeletion in distal 17p13.1: a recognizable phenotype with microcephaly, distinctive facial features, and intellectual disability.

Array comparative genomic hybridization has led to the identification of new syndromes by identifying genomic imbalances not detectable by standard karyotyping methods and by allowing correlations with physical findings. Deletions in the 17p13.1 region have been reported in patients with dysmorphic features and developmental delay but a consistent phenotype has yet to emerge. This report describes two unrelated patients with a characteristic phenotype associated with overlapping de novo deletions in the distal region of 17p13.1 detected with array comparative genomic hybridization and confirmed by real-time PCR. These patients share remarkably similar clinical features including microcephaly, mild developmental delay, generalized joint laxity, and a body posture with knee and elbow flexion and hands held in midline. They have distinctive facial features which include long midface with retrognathia with overbite, and protruding ears. The deletions in both patients are the smallest ever reported in this region (approximately 252 and 219 kb). The overlapping region contains 18 genes. Various isolated deletions of the 17p13.1 region have been reported previously without delineation of a consistent phenotype. We propose that the described microdeletions in the distal portion of 17p13.1 represent a novel microdeletion syndrome.

Plexiform neurofibroma of the eye region occurring in patients without neurofibromatosis type 1.

PURPOSE: The purpose of the present study was to investigate the correlation between Plexiform Neurofibroma (PN) of the eye region and Neurofibromatosis type 1 (NF1). According to the textbooks of ophthalmology, PN and NF1 are very closely linked. Our clinical experience raised doubts about this, however. METHODS: All biopsy reports from the Eye Pathology Institute, Copenhagen, for the 10-year period from 1999 to 2008 with PN as the histological diagnosis were identified. From the pathology referral forms, we determined whether the patients had had a history of NF1, and the medical records were reviewed for symptoms and signs of NF1. Patients with no known NF1 were invited for a clinical examination and a blood test for mutation analysis. RESULTS: 13 patients had been given the histological diagnosis of PN of the eye region during the 10-year period. Of these, 10 patients fulfilled the National Institute of Health (NIH) diagnostic criteria for NF1, but 3 patients had PN of the eye region as the only sign, and thus did not have NF1. In 2 of these patients, mutation analysis was performed on blood, and was negative. CONCLUSION: PN of the eye region is suggestive of NF1 but not pathognomonic of this disease.

Deficiency of the cytoskeletal protein SPECC1L leads to oblique facial clefting.

Genetic mutations responsible for oblique facial clefts (ObFC), a unique class of facial malformations, are largely unknown. We show that loss-of-function mutations in SPECC1L are pathogenic for this human developmental disorder and that SPECC1L is a critical organizer of vertebrate facial morphogenesis. During murine embryogenesis, Specc1l is expressed in cell populations of the developing facial primordial, which proliferate and fuse to form the face. In zebrafish, knockdown of a SPECC1L homolog produces a faceless phenotype with loss of jaw and facial structures, and knockdown in Drosophila phenocopies mutants in the integrin signaling pathway that exhibit cell-migration and -adhesion defects. Furthermore, in mammalian cells, SPECC1L colocalizes with both tubulin and actin, and its deficiency results in defective actin-cytoskeleton reorganization, as well as abnormal cell adhesion and migration. Collectively, these data demonstrate that SPECC1L functions in actin-cytoskeleton reorganization and is required for proper facial morphogenesis.

Craniofacial morphology in Muenke syndrome.

The purpose of this study was to test whether the severity of the cranial phenotype in Muenke syndrome infants with unicoronal synostosis is greater than in infants with nonsyndromic unicoronal synostosis. A total of 23 infants were included in the study. All infants included in the study had a computed tomography (CT)-verified synostosis of the coronal suture. The patients were either placed into the "Muenke" group (n=11) or the "non-Muenke" control group (n=12) on the basis of a test for the P250R mutation in the FGFR3 gene. On the basis of CT scans, a three-dimensional surface model corresponding to bone was created for each individual. The sutures were inspected for synostosis, and the degree of synostosis was assessed. Increased digital markings were recorded for both groups. Craniofacial morphology was assessed quantitatively using bony landmarks and recording of the midsagittal surface of the calvaria, cranial base, and maxillary complex. Increased digital markings were more severe posteriorly in Muenke patients than in non-Muenke patients. The Muenke patients with unilateral coronal synostosis showed a somewhat more severe asymmetry in the anterior part of the skull than the non-Muenke patients. The study indicates differences with regard to severity of increased digital markings and craniofacial asymmetry between the infants with Muenke syndrome and the infants with nonsyndromic unilateral coronal synostosis.

[Life-threatening subgaleal bleeding in a newborn infant]. / Livstruende subgaleal blødning hos nyfødt.

Subgaleal haematoma, also called subaponeurotic haemorrhage, is a serious but rarely seen form of bleeding that can occur as a complication to vacuum-assisted delivery. Subgaleal haemorrhage may be much more copious than the more common subperiostal bleeding, and can almost exsanguinate the infant. A pressure bandage applied to the upper head can be lifesaving.