A Case Series of Familial ARID1B Variants Illustrating Variable Expression and Suggestions to Update the ACMG Criteria

ARID1B is one of the most frequently mutated genes in intellectual disability (~1%). Most variants are readily classified, since they are de novo and are predicted to lead to loss of function, and therefore classified as pathogenic according to the American College of Medical Genetics and Genomics (ACMG) guidelines for the interpretation of sequence variants. However, familial loss-of-function variants can also occur and can be challenging to interpret. Such variants may be pathogenic with variable expression, causing only a mild phenotype in a parent. Alternatively, since some regions of the ARID1B gene seem to be lacking pathogenic variants, loss-of-function variants in those regions may not lead to ARID1B haploinsufficiency and may therefore be benign. We describe 12 families with potential loss-of-function variants, which were either familial or with unknown inheritance and were in regions where pathogenic variants have not been described or are otherwise challenging to interpret. We performed detailed clinical and DNA methylation studies, which allowed us to confidently classify most variants. In five families we observed transmission of pathogenic variants, confirming their highly variable expression. Our findings provide further evidence for an alternative translational start site and we suggest updates for the ACMG guidelines for the interpretation of sequence variants to incorporate DNA methylation studies and facial analyses.

Extremity anomalies associated with Robinow syndrome

Robinow syndrome, a rare genetic disorder, is characterized by skeletal dysplasia with, among other anomalies, extremity and hand anomalies. There is locus heterogeneity and both dominant and recessive inheritance. A detailed description of associated extremity and hand anomalies does not currently exist due to the rarity of this syndrome. This study seeks to document the hand anomalies present in Robinow syndrome to allow for improved rates of timely and accurate diagnosis. A focused assessment of the extremities and stature was performed using clinical examination and standard photographic images. A total of 13 patients with clinical and molecular diagnosis consistent with dominant Robinow syndrome or recessive Robinow syndrome were evaluated. All patients had limb shortening, the most common of which was mesomelia; however, rhizomelia and micromelia were also seen. These findings are relevant to clinical characterization, particularly as Robinow syndrome has classically been defined as a "mesomelic disorder." A total of eight distinct hand anomalies were identified in 12 patients with both autosomal recessive and dominant forms of Robinow syndrome. One patient did not present with any hand differences. The most common hand findings included brachydactyly, broad thumbs, and clinodactyly. A thorough understanding of the breadth of Robinow syndrome-associated extremity and hand anomalies can aid in early patient identification, improving rates of timely diagnosis and allowing for proactive management of sequelae.

Congenital radioulnar synostosis presenting in adulthood - a case report

Congenital radioulnar synostosis is a rare developmental skeletal malformation of the upper limb, characterized by the fusion of the proximal ends of the radius and ulna from birth. The failure of prenatal longitudinal segmentation of the adjacent radius and ulna results in a fibrous bony bridge between the radius and ulna. We present a 23-year-old female who presented with pain and restricted mobility of the left elbow joint for 7 years. A plain X-ray was performed for the patient, revealing a diagnosis of congenital radio-ulnar synostosis. Careful evaluation of the anatomical relations and spatial orientation of bony structures is required for the diagnosis and treatment of such cases.

Three additional patients with EED-associated overgrowth: potential mutation hotspots identified?

Variants have been identified in the embryonic ectoderm development (EED) gene in seven patients with syndromic overgrowth similar to that observed in Weaver syndrome. Here, we present three additional patients with missense variants in the EED gene. All the missense variants reported to date (including the three presented here) have localized to one of seven WD40 domains of the EED protein, which are necessary for interaction with enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2). In addition, among the seven patients reported in the literature and the three new patients presented here, all of the reported pathogenic variants except one occurred at one of four amino acid residues in the EED protein. The recurrence of pathogenic variation at these loci suggests that these residues are functionally important (mutation hotspots). In silico modeling and calculations of the free energy changes resulting from these variants suggested that they not only destabilize the EED protein structure but also adversely affect interactions between EED, EZH2, and/or H3K27me3. These cases help demonstrate the mechanism(s) by which apparently deleterious variants in the EED gene might cause overgrowth and lend further support that amino acid residues in the WD40 domain region may be mutation hotspots.

Morphological and neurophysiological impairment of the nerve in type II macrodactyly

Background

Macrodactyly is a congenital malformation characterized by aggressive overgrowth of multiple tissues, including subcutaneous fat, nerves, and bones in digits or limbs. In type II macrodactyly, the peripheral nerve is enlarged; however, the morphological and functional characteristics of the affected peripheral nerves have rarely been evaluated.

Methods

In this research, six macrodactyly patients and three polydactyly patients (control) were studied. Pre-operative sensory nerve action potential and intra-operative nerve action potential tests were performed. The microstructure and ultrastructure of the enlarged nerves were observed and neurofilament (NF) expression was evaluated using immunofluorescent staining.

Results

Axon impairment of the digital nerves originating from the median nerve (MN) was observed. A compensatory reinnervation from the ulnar nerve (UN) was found in two of the six patients, and significant morphological changes were observed in the enlarged nerve. The myelinated nerve fibers decreased, the lamellar structure of the myelin sheath changed, and the density of the NFs of the unmyelinated fibers decreased. There was aberrant distribution of NFs in the macrodactylous nerve tissues. In patients with compensatory UN reinnervation, the number of myelinated and unmyelinated fibers increased to normal levels; however, the diameter of the myelinated fibers apparently decreased.

Conclusions

The morphology and function of the macrodactylous enlarged nerve was impaired in type II macrodactyly patients; however, the unaffected UN partially compensated for the lost function of the affected MN under specific situations. Electrophysiological tests should be performed to determine the function of the affected nerve and surgical treatment for type II macrodactyly could be refined.

A novel microduplication of ARID1B: Clinical, genetic, and proteomic findings

Genetic alterations of ARID1B have been recently recognized as one of the most common mendelian causes of intellectual disability and are associated with both syndromic and non-syndromic phenotypes. The ARID1B protein, a subunit of the chromatin remodeling complex SWI/SNF-A, is involved in the regulation of transcription and multiple downstream cellular processes. We report here the clinical, genetic, and proteomic phenotypes of an individual with a unique apparent de novo mutation of ARID1B due to an intragenic duplication. His neurodevelopmental phenotype includes a severe speech/language disorder with full scale IQ scores 78-98 and scattered academic skill levels, expanding the phenotypic spectrum of ARID1B mutations. Haploinsufficiency of ARID1B was determined both by RNA sequencing and quantitative RT-PCR. Fluorescence in situ hybridization analysis supported an intragenic localization of the ARID1B copy number gain. Principal component analysis revealed marked differentiation of the subject's lymphoblast proteome from that of controls. Of 3426 proteins quantified, 1014 were significantly up- or down-regulated compared to controls (q < 0.01). Pathway analysis revealed highly significant enrichment for canonical pathways of EIF2 and EIF4 signaling, protein ubiquitination, tRNA charging and chromosomal replication, among others. Network analyses revealed down-regulation of: (1) intracellular components involved in organization of membranes, organelles, and vesicles; (2) aspects of cell cycle control, signal transduction, and nuclear protein export; (3) ubiquitination and proteosomal function; and (4) aspects of mRNA synthesis/splicing. Further studies are needed to determine the detailed molecular and cellular mechanisms by which constitutional haploinsufficiency of ARID1B causes syndromic and non-syndromic developmental disabilities.

FATCO Syndrome (Fibular Aplasia, Tibial Campomelia, Oligosyndactyly with Talar Aplasia). A Case Study

FATCO syndrome consists of fibular hemimelia, tibial campomelia and oligosyndactyly. FATCO syndrome can also be associated with other congenital anomalies; therefore, every case needs thorough evaluation so as to make the management of the patient easier. A few cases of this syndrome have been described in literature but only two cases have been reported in India so far. We present a 3-year-old male child born of a non-con-sanguinous marriage with FATCO syndrome and ipilateral talar aplasia without any other congenital anomalies.

PERIOPERATIVE CARE OF A CHILD WITH CRISPONI SYNDROME

Crisponi syndrome is an autosomal recessive disorder characterized by intermittent episodes of muscular contraction of the facial muscles with trismus and excessive salivation simulating a tetanic spasm. These episodes occur in response to tactile stimulation or during crying. Associated physical and constitutional findings include characteristic facial anomalies, camptodactyly, intermittent hyperthermia, and feeding difficulties. We present a 15-month-old girl who required anesthetic care during laparoscopic fundoplication and gastric tube insertion. The perioperative implications of the disorder are reviewed and suggestions for anesthetic management provided.

The Use of Composite Tissue Spare Parts to Restore Tripod Hand Function in Post-Traumatic and Congenital Hand Deficiency

The principle aim in complex defects in hand is to restore a functioning tripod pinch. Among the various options, the use of locally available spare parts offers to improve both functions and cosmetics. 10 patients underwent surgeries to restore tripod pinch using this concept of spare parts. Four of them were children with congenital differences and the rest were adults with post traumatic defects. Eight of them underwent on-top plasty out of which four underwent an island pedicled transfer of phalanges and the rest involved distraction lengthening and transfer of metacarpals. One patient underwent a vascularized tenocutaneous joint transfer and another, a non-vascularized metacarpal transfer. At last follow up, eight of them were using hand with tripod pinch and one, using a lateral pinch. A carefully planned use of local tissues as spare part results in satisfactory outcome without the need for additional graft material in hands with absent or poor function.

Congenital Clasped Thumb That Is Forgetten a Syndrome in Clinical Practice: A Case Report

Congenital clasped thumb is a progressive flexion and adduction deformity presenting with heterogeneous congenital anomalies. Although the disease is rare, diagnosis is usually delayed due to natural location of thumb within the palm in first 3 months of life. A 4-year-old girl with congenital clasped thumb deformity due to absence of extensor pollicis brevis tendon whose treatment consisted of extensor indicis proprius (EIP) transfer and z-plasty reconstruction to first web space. The patient was so happy with both cosmetic appearance and functional status. There was not any limitation at interphalangeal or metacarpophalangeal (MCP) joints of the thumb and the result was. Stability of MCP joint was full and power for grasping any object was much better than the original status. In cases of isolated clasped thumb deformity associated with absence of tendon whose treatment attempts with splinting and physical treatment have failed, EIP tendon transfer and reconstruction of contracture in first web space with z-plasty is an easy and successful method to obtain functional improvement.

Mammalian cadherins DCHS1-FAT4 affect functional cerebral architecture

Cortical development is a complex process where a multitude of factors, including cadherins, plays an important role and where disruptions are known to have far reaching effects in neural development and cortical patterning. Cadherins play a central role in structural left-right differentiation during brain and body development, but their effect on a functional level remains elusive. We addressed this question by examining functional cerebral asymmetries in a patient with Van Maldergem Syndrome (VMS) (MIM#601390), which is caused by mutations in DCHS1-FAT4 cadherins, using a dichotic listening task. Using neurophysiological (EEG) data, we show that when key regulators during mammalian cerebral cortical development are disrupted due to DCHS1-FAT4 mutations, functional cerebral asymmetries are stronger. Basic perceptual processing of biaurally presented auditory stimuli was unaffected. This suggests that the strength and emergence of functional cerebral asymmetries is a direct function of proliferation and differentiation of neuronal stem cells. Moreover, these results support the recent assumption that the molecular mechanisms establishing early left-right differentiation are an important factor in the ontogenesis of functional lateralization.

[The effectiveness of combined treatment of the children with congenital radial and ulna club hand]

The purpose of the investigation is the analysis of the treatment results of the children with congenital club hand. The study was based on the treatment results of 35 patients with congenital club hand. All of them have anomaly of the hand. The patients are divided into 2 groups. The first group includes 13 patients who had surgical treatment: centralization or radialization of the wrist, distraction lengthening of the forearm and the correction of the ulna. The second group includes 22 patients who had the combination surgery of the forearm and the hand. The best functional treatment results have the patients of the second group who had the combination surgery of the forearm and the hand.

Treatment of camptodactyly using injection of botulinum neurotoxin

BACKGROUND

Camptodactyly is usually painless, not caused by trauma, often appearing bilaterally, gradually progressive flexion contracture of the proximal interphalangeal joint mainly on the 5th fingers.

OBJECTIVES

The aim of the study was to analyze the efficacy injecting botulinum neurotoxin in short muscles of the hand responsible for the contraction of the proximal interphalangeal joint.

MATERIAL AND METHODS

The clinical material consisted of 12 patients (8 women, 4 men) treated with injections of botulinum neurotoxin in 2009-2012. Patients were monitored respectively for 2 weeks, 3 and 6 months and then every six months after the procedure. The observation period after injection of toxin ranged from 18 to 36 months. Our proposed method of treatment is inducing a temporary paralysis of muscles (lumbrical, interosseous) by means of botulinum neurotoxin (Botox).

RESULTS

In the majority (10) of patients an improvement and stabilization was achieved just after one injection and there were no disease progression in subsequent controlled studies. These patients continued treatment with usage of redressing extensive splints. In case of the other two patients it was required to repeat the injections.

CONCLUSIONS

The preliminary results obtained are promising. This method of treatment requires further studies and long-term follow-ups every six months until release of symptoms of the disease will be achieved. The operative treatment is reserved for severe deformities.

[Posterior interosseous flap in pediatric hand reconstructions]

The results of hand reconstructions with posterior interosseous flap were studied in 10 children (4 males and 6 females) aged from 1 year to 13 years old. In 4 cases flap coverage was performed due to acquired posttraumatic hand deformity, in 6 cases reconstruction was assumed for congenital hand deformities. Combined procedures consisted of posterior interosseous flap coverage and other types of microsurgical reconstructions were suggested in all 10 patients. Preoperative color Doppler visualization of the posterior interosseous vessels was mandatory. All flaps were risen under 3.5-4.5X magnification. All flaps survived completely in 3 weeks postoperatively. There were not postoperative complications such as flap's arterial or venous insufficiency, deep infection, or posterior interosseous nerve palsy. Nearly whole group (9 of 10) of patients and/or their parents were satisfied with the esthetic view of the reconstructed hand and donor site of the forearm 1 year postoperatively.

Weaver syndrome and EZH2 mutations: Clarifying the clinical phenotype

Weaver syndrome, first described in 1974, is characterized by tall stature, a typical facial appearance, and variable intellectual disability. In 2011, mutations in the histone methyltransferase, EZH2, were shown to cause Weaver syndrome. To date, we have identified 48 individuals with EZH2 mutations. The mutations were primarily missense mutations occurring throughout the gene, with some clustering in the SET domain (12/48). Truncating mutations were uncommon (4/48) and only identified in the final exon, after the SET domain. Through analyses of clinical data and facial photographs of EZH2 mutation-positive individuals, we have shown that the facial features can be subtle and the clinical diagnosis of Weaver syndrome is thus challenging, especially in older individuals. However, tall stature is very common, reported in >90% of affected individuals. Intellectual disability is also common, present in ~80%, but is highly variable and frequently mild. Additional clinical features which may help in stratifying individuals to EZH2 mutation testing include camptodactyly, soft, doughy skin, umbilical hernia, and a low, hoarse cry. Considerable phenotypic overlap between Sotos and Weaver syndromes is also evident. The identification of an EZH2 mutation can therefore provide an objective means of confirming a subtle presentation of Weaver syndrome and/or distinguishing Weaver and Sotos syndromes. As mutation testing becomes increasingly accessible and larger numbers of EZH2 mutation-positive individuals are identified, knowledge of the clinical spectrum and prognostic implications of EZH2 mutations should improve.

Tel Hashomer camptodactyly syndrome: a case report

Tel Hashomer camptodactyly syndrome (THCS) is a rare autosomal recessive camptodactyly with muscular involvement. The manifestations of THCS other than camptodactyly are clubbed feet, thenar and hypothenar hypoplasia, abnormal palmar creases and dermatoglyphic ridges, spina bifida and mitral valve prolapse. The syndrome was first described by Goodman et al in 1972 and thereafter two further cases with similar phenotype were seen. Herein, we present another case report and review of the literature of other syndromes associated with camptodactyly and mitral valve prolapse. Further cases with this syndrome need to be reported for mapping of the candidate loci. This will help in planning management and genetic counselling.

TOE-TO-HAND TRANSFER IN SYMBRACHYDACTYLY

Symbrachydactyly, or central atypical cleft, is classified as a failure of formation. For the adactylous or monodactylous forms, free toe transfer is the treatment of choice. We present 18 free toe transfers in 13 patients for symbrachydactyly. Despite abnormal anatomy, the functional building blocks have always been available and transfer technically possible. The result has been improved function and high levels of parental satisfaction.

MLK3 regulates bone development downstream of the faciogenital dysplasia protein FGD1 in mice

Mutations in human FYVE, RhoGEF, and PH domain-containing 1 (FGD1) cause faciogenital dysplasia (FGDY; also known as Aarskog syndrome), an X-linked disorder that affects multiple skeletal structures. FGD1 encodes a guanine nucleotide exchange factor (GEF) that specifically activates the Rho GTPase CDC42. However, the mechanisms by which mutations in FGD1 affect skeletal development are unknown. Here, we describe what we believe to be a novel signaling pathway in osteoblasts initiated by FGD1 that involves the MAP3K mixed-lineage kinase 3 (MLK3). We observed that MLK3 functions downstream of FGD1 to regulate ERK and p38 MAPK, which in turn phosphorylate and activate the master regulator of osteoblast differentiation, Runx2. Mutations in FGD1 found in individuals with FGDY ablated its ability to activate MLK3. Consistent with our description of this pathway and the phenotype of patients with FGD1 mutations, mice with a targeted deletion of Mlk3 displayed multiple skeletal defects, including dental abnormalities, deficient calvarial mineralization, and reduced bone mass. Furthermore, mice with knockin of a mutant Mlk3 allele that is resistant to activation by FGD1/CDC42 displayed similar skeletal defects, demonstrating that activation of MLK3 specifically by FGD1/CDC42 is important for skeletal mineralization. Thus, our results provide a putative biochemical mechanism for the skeletal defects in human FGDY and suggest that modulating MAPK signaling may benefit these patients.

Familial or genetic primary aldosteronism and Gordon syndrome

Salt-sensitive forms of hypertension have received considerable renewed attention in recent years. This article focuses on 2 main forms of salt-sensitive hypertension (familial or genetic primary aldosteronism [PA] and Gordon syndrome) and the current state of knowledge regarding their genetic bases. The glucocorticoid-remediable form of familial PA (familial hyperaldosteronism type I) is dealt with only briefly because it is covered in depth elsewhere.

Unilateral duplication of palmar arterial arches--a case report

Recent progress in hand surgery has engendered a need for precise knowledge of anatomical variations of blood supply of hand. The present paper describes an unusual organization of palmar arterial arches and attempts to discuss its clinical implications. Double superficial palmar arch of the mediano-ulnar variant was observed with a double deep palmar arch of equal caliber, formed by splitting of deep branches of radial artery and ulnar artery. The superficial palmar branch of radial artery was absent.

Differences in the activity of the muscles in the forearm of individuals with a congenital absence of the hand

The spectral content of the myoelectric signals from the muscles of the remnant forearms of three persons with congenital absences (CA) of their forearms was compared with signals from their intact contra-lateral limbs, similar muscles in three persons with acquired losses (AL) and seven persons without absences [no loss (NL)]. The observed bandwidth for the CA subjects was broader with peak energy between 200 and 300 Hz. While the signals from the contra-lateral limbs and the AL and NL subjects was in the 100-150 Hz range. The mean skew of the signals from the AL subjects was 46.3 +/- 6.7 and those with NL of 45.4 +/- 8.7, while the signals from those with CAs had a skew of 11.0 +/- 11. The structure of the muscles of one CA subject was observed ultrasonically. The muscle showed greater disruption than normally developed muscles. It is speculated that the myographic signal reflects the structure of the muscle which has developed in a more disorganized manner as a result of the muscle not being stretched by other muscles across the missing distal joint, even in the muscles that are used regularly to control arm prostheses.

Aplasics Born without Hands Mirror the Goal of Hand Actions with Their Feet

The premotor and parietal mirror neuron system (MNS) is thought to contribute to the understanding of observed actions by mapping them onto "corresponding" motor programs of the observer [1-24], but how would the MNS respond to the observation of hand actions if the observer never had hands? Would it not show changes of blood-oxygen-level dependent (BOLD) signal, because the observer lacks motor programs that can resonate [12, 25, 26], or would it show significant changes because the observer has motor programs for the foot or mouth with corresponding goals [15, 17, 19, 27, 28]? We scanned two aplasic subjects, born without arms or hands, while they watched hand actions and compared their brain activity with that of 16 control subjects. All subjects additionally executed actions with different effectors (feet, mouth, and, for controls, hands). The BOLD signal of aplasic individuals within the putative MNS was augmented when they watched hand actions, demonstrating the brain's capacity to mirror actions that deviate from the embodiment of the observer by recruiting voxels involved in the execution of actions that achieve corresponding goals by different effectors. This sheds light on the functional organization of the MNS and predominance of goals in imitation.

Precision grip function after free toe transfer in children with hypoplastic digits

Although toe-to-hand transfer has a defined role in the management of congenital hand deformities, it remains unclear how well children integrate the transferred digits into physiological grasping. We analysed fingertip forces in the precision grip of 13 patients when lifting a test object more than three years after free toe transfer for absent or hypoplastic digits. Clinically, most patients showed normal sensibility of transferred digits, but active motion and pinch strength were limited as compared to the normal hand. For the control of fingertip forces, two key features of the normal two-digit opposition grip were seen in all operated hands: adaptation of grip force to object weight and parallel coordination of lift and grip forces. These physiological grasping strategies developed independently of the patients' age at the time of operation, which ranged from one to 13 years. In four patients, we observed increased tangential load forces with the operated hand due to misalignments in the application of fingertips on the grasp surfaces. Such forces lead to increased grip force requirements on both fingers that may overload transferred digits with limited motor function. The need for optimal alignment of the grip axis during toe-transfer surgery is emphasised.

Bilateral hands and feet postaxial polydactyly presenting with renal vascular anomalies

The current Observation reports polydactyly of both the hands and feet in a 36 years old male cadaver that presented also with supernumerary renal vessels. The right kidney received the upper and lower supernumerary renal arteries from the abdominal aorta and was drained by the two renal veins. The anterior and posterior supernumerary renal veins opened separately into the inferior vena cava. Observations on the limbs revealed the presence of six digits in the four limbs. In the hands the extra digit contained two phalanges and rudimentary metacarpals that were pear-shaped. The pointed ends of the metacarpals articulated with the soft tissue at the lateral side of the fifth digit and the base articulated with the proximal phalanx. In the feet the proximal phalanges in the extra digits articulated with the anomalous metatarsals. The left foot presented with bifurcated fifth metatarsal and the most lateral part articulated with the extra digit. In the left foot the extra toes was pointing upward away from the plantar surface. Close observations revealed an oblique shaped cavity on the lateral surface of the fifth metatarsal. The cavity was situated about 1cm from the distal end of the fifth metatarsal. It contained short ligaments and its upper part articulated with the head of the proximal phalanx. The current observations has documented for the first time the occurrence of renal vascular anomalies with polydactyly of both hands and feet.

Upper extremity function in children with congenital hand anomalies

The enhancement of function takes priority in the management of children with congenital hand anomalies. The authors conducted a systematic review of studies of pollicization and centralization surgery to examine functional outcome. The search strategy included MEDLINE, CINAHL, and reference lists from secondary resources. The selection criteria included all literature pertaining to the functional outcome of children having either pollicization or centralization surgery. The studies were analyzed according to the levels of evidence for primary research. Ten studies were reviewed; one study was evaluated at level 3 and the remaining were level 4. Rigorous research of functional outcome is needed to validate surgical interventions. Enhancing the quality of functional outcome studies in this population requires improvements in research methodology, sampling, and measurement of function.

Correction of bilateral congenital swan-neck deformity by use of Mitek mini anchor: a new technique

Congenital swan neck deformity is a rare condition, secondary to congenital laxity of the palmar plate of the proximal interphalangeal joint. Here, we describe a new surgical method which is based on the palmar plate reinforcement using the Mitek mini anchor system (Mitek Surgical Products Inc., Norwood, MA, USA). Four fingers of a patient with congenital swan neck deformities were corrected with this technique at two stages. First, the anchor was inserted into the volar surface of the proximal phalanx. The two sutures of the anchor system were then crossed the PIP joint in a V fashion. Two holes, 5mm apart from each other, were created through the middle phalanx distal to both insertion points of superficial flexor tendon. The suture ends of the anchor were passed through these holes from the volar to the dorsal side of the middle phalanx and then turned around the edges of the bone to the volar surface. They were tied to each other as the PIP joint was stabilised at 20 degrees flexion by use of a K-wire. The K-wire was removed 21 days later and a rehabilitation program was then initiated. A second operation for the two fingers of the opposite hand was performed 2 months after the first operation. No postoperative complications were encountered. At 2 years follow-up, the active range of motion was within normal limits at PIP and DIP joints of all four fingers without any recurrence of hyperextension or hyperflexion. The final result was satisfactory regarding both the functional and cosmetic aspects. The Mitek mini anchor offers a practical, reliable and functional reconstruction of the volar plate in the management of congenital swan neck deformities. We believe that it may also be used for the acquired deformities.

Catel-Manzke syndrome: a case report of a female with severely malformed hands and feet. An extension of the phenotype or a new syndrome?

An unusual case of a female infant with Catel-Manzke syndrome is presented. Additional features not previously reported include three accessory ossicles at the bases or associated with the proximal phalanx of the index, middle, ring and little fingers bilaterally. There are also numerous bony abnormalities in both feet. Previous cases have shown no more than 2 accessory ossicles in the hand and these usually involve the index alone. The foot abnormalities are more extensive than any previously seen in this syndrome. This is only the 8th female case out of a total of 27 reported cases.

Hypertrichosis, Fallot tetralogy, growth and developmental delay

We report a female patient with a unique pattern of pre- and postnatal growth deficiency, tetralogy of Fallot, very long eyelashes (trichomegaly), progressive and generalized hypertrichosis lanuginosa, brain atrophy with epilepsy, and puffy hands and feet. This appears to be a "new" entity within the group of syndromal hypertrichoses, possibly pathogenetically related to, but clinically distinct from Ambras or Oliver-McFarlane syndromes.

Mendelian hypertension with brachydactyly as a molecular genetic lesson in regulatory physiology

Mendelian forms of hypertension have delivered a treasure trove of novel genes. To date, the molecular mechanisms of five such syndromes have been largely clarified, including glucocorticoid-remediable aldosteronism, Liddle's syndrome, apparent mineralocorticoid excess, an activating mutation of the mineralocorticoid receptor, and pseudohypoaldosteronism type 2. Each of these conditions features salt sensitivity with increased sodium and volume reabsorption by the kidney and low plasma renin activity. None of the gene loci for these syndromes has been convincingly linked to hypertension in the general population. We are investigating kindreds who have autosomal-dominant hypertension and brachydactyly. Affected persons invariably have both anomalies. The hypertension is severe and results in death at about age 50 years from stroke. The condition resembles essential hypertension, because renin, aldosterone, and norepinephrine responses are normal and no salt sensitivity is present. The response to antihypertensive drugs is general. Another feature is diminished baroreflex sensitivity with markedly impaired blood pressure buffering. Furthermore, the ventrolateral medulla may be compromised in these patients, because neurovascular anomalies are a regular finding. We mapped the gene(s) for this disease to chromosome 12p and narrowed the chromosomal region by studying more affected families. Interestingly, the same locus was recently mapped in Chinese families with essential hypertension. Our 3-centimorgan region contains genes encoding a phosphodiesterase, an ATP-dependent potassium channel, and its regulator the sulfonylurea receptor 2. Screening of the coding regions revealed that none of these candidate genes harbor obvious mutations; however, other genetic mechanisms may nevertheless compromise their function. Our study underscores the importance of regulatory physiology to the understanding of a complex genetic syndrome.

A novel mutation of keratin 9 in epidermolytic palmoplantar keratoderma combined with knuckle pads

Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominantly inherited disease. We studied a family from Shandong, China, having patients suffering from EPPK with a unique symptom-knuckle pads. We noticed that both the hyperkeratosis and knuckle pads in the Chinese family were friction-related. Candidate gene analysis was carried out using linkage analysis and direct sequencing. A novel L160F mutation in keratin 9 was found, and its effects on the secondary structure of keratin 9 were studied. We predict that the L160F mutation is also responsible for the knuckle pads in the family. Our study provides a new clue for the study of the function of keratin 9.

Facial dysmorphism, multiple pigmented nevi, osteoporosis, brachydactyly, and other skeletal changes in a male: a new syndrome?

A adult male is described with facial dysmorphism, multiple pigmented nevi, osteoporosis, and multiple skeletal anomalies. This combination does not fit any known syndromes and may represent a new entity.

A 117-kb microdeletion removing HOXD9-HOXD13 and EVX2 causes synpolydactyly

Studies in mouse and chick have shown that the 5' HoxD genes play major roles in the development of the limbs and genitalia. In humans, mutations in HOXD13 cause the dominantly inherited limb malformation synpolydactyly (SPD). Haploinsufficiency for the 5' HOXD genes has recently been proposed to underlie the monodactyly and penoscrotal hypoplasia in two children with chromosomal deletions encompassing the entire HOXD cluster. Similar deletions, however, have previously been associated with split-hand/foot malformation (SHFM), including monodactyly. Here we report a father and daughter with SPD who carry a 117-kb microdeletion at the 5' end of the HOXD cluster. By sequencing directly across the deletion breakpoint, we show that this microdeletion removes only HOXD9-HOXD13 and EVX2. We also report a girl with bilateral split foot and a chromosomal deletion that includes the entire HOXD cluster and extends approximately 5 Mb centromeric to it. Our findings indicate that haploinsufficiency for the 5' HOXD genes causes not SHFM but SPD and point to the presence of a novel locus for SHFM in the interval between EVX2 and D2S294. They also suggest that there is a regulatory region, upstream of the HOXD cluster, that is responsible for activating the cluster as a whole.

Magnetic resonance angiography of the forearm and hand in children

A two-dimensional time-of-flight magnetic resonance angiography was performed in 29 arms in 25 pediatric patients with congenital hand abnormalities, whose average age was three years and eight months. Venous structures were eliminated with presaturation technique and the remaining arterial system was evaluated. Magnetic resonance angiography demonstrated major arteries in the forearm well but not their branches. Even the biggest branch of the artery sometimes could not be detected. Magnetic resonance angiography and Allen test were consistent in determining patency of the palmar arch in 62% of the cases but the sensitivity was only 28%. Our experience showed that non-invasive, convenient, two-dimensional time-of-flight magnetic resonance angiography was useful for detecting continuity and spatial localisation of the major arteries in a child's forearm. However, it was not a complete alternative to conventional angiography and was unsatisfactory in delineating the vascular anatomy in the hand.

Congenital vascular malformations in the hand and forearm

PURPOSE

To review a single-center experience in the management of symptomatic congenital vascular malformations of the hand and forearm with special attention to embolotherapy.

METHODS

A retrospective chart review was performed to identify patients with vascular malformations referred for arteriography and possible intervention between 1983 and 1998. Arteriography and venography were performed in all patients to differentiate between true high-flow arteriovenous malformations (AVM) and low-flow primary venous malformations (PVM). The clinical and radiological data, procedural results, and follow-up data were retrieved and reviewed.

RESULTS

In a 15-year period, 39 patients (22 men; mean age 22.5 years, range 1-51) had symptomatic vascular lesions diagnosed in the forearm and hand: 21 AVMs, 17 PVMs, and one complex lesion with both AVM and PVM. Thirty-four (87%) lesions were treated with immediate technical success achieved in 31 (91%) cases; 5 (13%) lesions were not amenable to percutaneous treatment. There were no major complications, but 3 embolized AVMs had significant residual flow (81.6% technical success on intention to treat basis). Long-term follow-up ranging to 5 years was available in 26 of the 34 treated patients; the mean symptom-free period was 30 months for the AVM patients and 30.5 months for the PVM group, with an average of 1.5 and 1.2 embolization procedures, respectively.

CONCLUSIONS

Vascular malformations of the hand and forearm are extremely rare lesions that demand a multidisciplinary approach for optimal diagnosis and management. Microembolotherapy with or without surgery has offered the highest level of safety and success to date.

Parent-offspring resemblance of palmar and plantar dermatoglyphic patterns in Down syndrome

With the aim of investigating the influence of trisomy 21 on the expression of heritable morphological features, we recorded the palmar and plantar dermatoglyphic patterns in 48 children with Down syndrome (DS), in both their parents, and, as a control, in 57 of their siblings. Using the Kendall tau rank correlation test, a considerable parental influence on the frequency of true patterns in the interdigital areas (IDA) III and IV of the palms (P = 0.3%) and soles (P = 1.0% and 3.8%, respectively) is demonstrated for the control siblings. In the children with DS, this influence is discernible as well, although with no statistical significance. A greater number of families may be required to settle the question.

Distinct mutations in the receptor tyrosine kinase gene ROR2 cause brachydactyly type B

Brachydactyly type B (BDB) is an autosomal dominant skeletal disorder characterized by hypoplasia/aplasia of distal phalanges and nails. Recently, heterozygous mutations of the orphan receptor tyrosine kinase (TK) ROR2, located within a distinct segment directly after the TK domain, have been shown to be responsible for BDB. We report four novel mutations in ROR2 (two frameshifts, one splice mutation, and one nonsense mutation) in five families with BDB. The mutations predict truncation of the protein within two distinct regions immediately before and after the TK domain, resulting in a complete or partial loss of the intracellular portion of the protein. Patients affected with the distal mutations have a more severe phenotype than do those with the proximal mutation. Our analysis includes the first description of homozygous BDB in an individual with a 5-bp deletion proximal to the TK domain. His phenotype resembles an extreme form of brachydactyly, with extensive hypoplasia of the phalanges and metacarpals/metatarsals and absence of nails. In addition, he has vertebral anomalies, brachymelia of the arms, and a ventricular septal defect-features that are reminiscent of Robinow syndrome, which has also been shown to be caused by mutations in ROR2. The BDB phenotype, as well as the location and the nature of the BDB mutations, suggests a specific mutational effect that cannot be explained by simple haploinsufficiency and that is distinct from that in Robinow syndrome.

An experience of the Snow-Littler procedure

This paper reviews the results of the Snow-Littler procedure performed in twelve hands with classical central longitudinal deficiency and in one hand with symbrachydactyly, cleft type. There were no instances of major flap necrosis although two flaps showed tip ischaemia. The width of the first web was, in the main, satisfactory but four webspace revisions were performed. Supplementary skin grafting at the time of surgery was necessary in complete and/or complex thumb index syndactylies and in the patient with symbrachydactyly. In eight cases, a transverse metacarpal ligament was reconstructed. In the five other cases, no clinical instability or radiological divergence of the index and ring fingers occurred, in spite of no transverse metacarpal ligament reconstruction. Three de-rotational osteotomies of transposed index fingers were performed in patients who had a transverse metacarpal ligament reconstruction. These results indicated significantly improved appearance and improved function following the Snow-Littler procedure.

[Value of a new first web space reconstruction in congenital hand deformities. A study of 54 patients]

INTRODUCTION

Only a few studies are available in the literature on the specific problem of the congenital contracture or absence of the first web in hand deformities, and first web reconstruction.

MATERIAL AND METHODS

Sixty-seven first web plasties in 54 patients were retrospectively analyzed: they included 44 cases of classical plasties, i.e., Z-plasty (21 cases); dorsal flap plasty of the index (19 cases), thumb (1 case), or the hand (10 cases), and 16 cases of' pseudo-kite flap.

RESULTS

The results were difficult to assess, as the syndromes were dissimilar and the deformities were not comparable (e.g., Apert syndrome versus Poland syndrome). However, it was found that the 'pseudo-kite' technique which was applicable to certain cases resulted in a web extension of 3.2 cm without any deepening.

DISCUSSION

No method of classical assessment can be used to comprehensively evaluate the results of first web reconstruction due to the wide variability in clinical characteristics, the lack of patient cooperation in this young age group, the possible MPJ articular thumb instability, and growth factors. Although 4-flap Z-plasty is an adequate technique for non-severe first web deformities, the 'pseudo-kite' flap approach is useful in more severe cases. In 13 cases, a peroperative measurement before and following plasty was made, and a significant increase (205%) in planimetric and stereotactic gain compared to pre-plasty findings was noted.

CONCLUSION

It does not seem logical to have a particular preference for a certain approach when considering first web reconstruction in congenital malformations. Each technique has its advantages and disadvantages, depending on patient age, the type of malformation, the state of the thumb, the extent of the first web deformity and the possible presence of scar tissue.

Precision grip with congenital hypoplasty or hypofunction of the thumb

We tested the grip in four patients with congenital defects of the hand and either a hypoplastic thumb or a thumb with impaired inervation. Small objects were taken by a scissors grip between the fingers. In a hand with radial duction in the manus vara congenita, during strengthening of the wrist, the grip from the ulnar side between the fourth and fifth fingers was changed to the radial side between the second and third fingers. Large objects were gripped by all the three-phalanx fingers into the palm in a horizontal position. In case 4 with hypoplasia of the thumb grade IIIC by the classification of Blauth and Buck-Gramcko, we describe a transposition of the index finger to the site of the thumb and the hypoplastic thumb to the site of the index finger. It is obvious that the precision grip is affected by the thumb length and strengthening of the ulnar side of the wrist. We assume that the scissors grip is the earliest precision grip in the evolution of the primate hand.

Limb mammary syndrome: a new genetic disorder with mammary hypoplasia, ectrodactyly, and other Hand/Foot anomalies maps to human chromosome 3q27

We report on a large Dutch family with a syndrome characterized by severe hand and/or foot anomalies, and hypoplasia/aplasia of the mammary gland and nipple. Less frequent findings include lacrimal-duct atresia, nail dysplasia, hypohydrosis, hypodontia, and cleft palate with or without bifid uvula. This combination of symptoms has not been reported previously, although there is overlap with the ulnar mammary syndrome (UMS) and with ectrodactyly, ectodermal dysplasia, and clefting syndrome. Allelism with UMS and other related syndromes was excluded by linkage studies with markers from the relevant chromosomal regions. A genomewide screening with polymorphic markers allowed the localization of the genetic defect to the subtelomeric region of chromosome 3q. Haplotype analysis reduced the critical region to a 3-cM interval of chromosome 3q27. This chromosomal segment has not been implicated previously in disorders with defective development of limbs and/or mammary tissue. Therefore, we propose to call this apparently new disorder "limb mammary syndrome" (LMS). The SOX2 gene at 3q27 might be considered an excellent candidate gene for LMS because the corresponding protein stimulates expression of FGF4, an important signaling molecule during limb outgrowth and development. However, no mutations were found in the SOX2 open reading frame, thus excluding its involvement in LMS.

Brachydactyly type B: clinical description, genetic mapping to chromosome 9q, and evidence for a shared ancestral mutation

Autosomal dominant brachydactyly type B (BDB) is characterized by nail aplasia with rudimentary or absent distal and middle phalanges. We describe two unrelated families with BDB. One family is English; the other family is Canadian but of English ancestry. We assigned the BDB locus in the Canadian family to an 18-cM interval on 9q, using linkage analysis (LOD score 3.5 at recombination fraction [theta] 0, for marker D9S938). Markers across this interval also cosegregated with the BDB phenotype in the English family (LOD score 2.1 at straight theta=0, for marker D9S277). Within this defined interval is a smaller (7.5-cM) region that contains 10 contiguous markers whose disease-associated haplotype is shared by the two families. This latter result suggests a common founder among families of English descent that are affected with BDB.

[Analysis of hand function with the Millesi examination scale in patients with pollicisation after aplasia or hypoplasia of the thumb]

Pollicisation of a single long finger is the method of choice to treat congenital thumb aplasia or thumb hypoplasia. Using Millesi's scale for the functional analysis of the hand, we examined six patients treated in the years 1983 to 1994 in our service. Average age at the time of surgery was 2.4 years and the follow-up time was seven years on average. Of the six patients, four suffered from additional malformations of the ipsilateral arm. These anomalies required early surgical treatment and therefore delayed the pollicisation procedure. The results of the anatomical part of the examination ranged between 39 and 94% of the achievable value. The final results including sensibility, strength, and skills reached 11 to 50%. Development of skills and muscle strength in the operated hand was dependent on the follow-up time. Millesi's scale could be applied successfully in this special group of children with congenital malformation of hands.

Hand function in children with cerebral palsy after upper-limb tendon transfer and muscle release

Thirty-two children with hand dysfunction due to cerebral palsy were examined before tendon transfer and muscle release, and 9 months postoperatively. All children improved their performance regardless of the degree of impaired hand function. The main advantage of surgery was a more functional position of the hand with increased wrist extension and forearm supination. There were also increased functionality of handgrips, grip strength, and dexterity. Impaired sensibility before surgery did not influence the outcome. Individual goals were set preoperatively. Individual functional goals outlined before surgery were met by most children. Children identified as having mild impairments gained new functional skills related to everyday activity (self-care and leisure), while children with severely impaired hand function demonstrated enhanced grasping ability, as well as a better cosmetic appearance.

Robinow syndrome, vaginal atresia, hematocolpos, and extra middle finger

A 14-year-old girl with Robinow syndrome was admitted with severe abdominal pain that had recurred periodically during the last 6 months. She had been followed by us since age 2 months and she had not experienced menarche yet; hematocolpos related to vaginal atresia was diagnosed. She underwent vaginoplasty with cervical construction. Genital system abnormalities are common in Robinow syndrome, but this kind of malformation has not been reported previously.

New recessive syndrome characterized by increased chromosomal breakage and several findings which overlap with Fanconi anemia

We describe four cases with several findings of Fanconi anemia (FA), but without hypersensitivity to DNA cross-linking that is the distinguishing characteristic of FA. Two of the cases are male and female sibs of Hispanic origin, age 6 years and 11 months, respectively. Both have short stature, failure to thrive, absent thumbs, short palpebral fissures, and skin pigmentation abnormalities. The girl also has developmental "dysplasia" of her hips. Presently, both siblings are hematologically normal. Elevated baseline chromosome breakage was observed in the boy, but not in the girl. Neither sib showed elevated diepoxybutane (DEB)-induced chromosomal breakage. In a subsequent pregnancy, prenatal studies showed slightly elevated baseline and DEB induced chromosome breakage (greater than normal, but lower than the established range for FA). The fetus had intrauterine growth retardation and an absent right thumb. A review of cases referred to the International Fanconi Anemia Registry for DEB testing showed one additional case with similar findings. That patient, a girl, of Caucasian English ancestry, age 14 years, had short stature, a history of failure to thrive, skin pigmentation abnormalities, absent right thumb, hypoplastic left thumb, and hydrocephalus that resolved spontaneously. Elevated baseline chromosome breakage was observed in skin fibroblasts but not in lymphocytes. We postulate that these cases represent a previously undescribed autosomal recessive syndrome. These and other previously reported cases provide evidence for alternative genetic mechanisms that may result in developmental anomalies similar to those seen in FA.