Establishment and characterization of ZJUCHi003: an induced pluripotent stem cell line from a patient with Temple-Baraitser/Zimmermann-Laband syndrome carrying KCNH1 c.1070G > A (p.R357Q) variant

Pathogenic variants of the KCNH1 gene can cause dominant-inherited Temple-Baraitser/Zimmermann-Laband syndrome with severe mental retardation, seizure, gingival hyperplasia and nail hypoplasia. This study established an induced pluripotent stem cell (iPSC) line using urinary cells from a girl with KCNH1 recurrent/hotspot pathogenic variant c.1070G > A (p.R357Q). The cell identity, pluripotency, karyotypic integrity, absence of reprogramming virus and mycoplasma contamination, and differential potential to three germ layers of the iPSC line, named as ZJUCHi003, were characterized and confirmed. Furthermore, ZJUCHi003-derived neurons manifested slower action potential repolarization process and wider action potential half-width than the normal neurons. This cell line will be useful for investigating the pathogenic mechanisms of KCNH1 variants-associated symptoms, as well as for evaluating novel therapeutic approaches.

Potassium Channel KCNH1 Activating Variants Cause Altered Functional and Morphological Ciliogenesis

The primary cilium is a non-motile sensory organelle that extends from the surface of most vertebrate cells and transduces signals regulating proliferation, differentiation, and migration. Primary cilia dysfunctions have been observed in cancer and in a group of heterogeneous disorders called ciliopathies, characterized by renal and liver cysts, skeleton and limb abnormalities, retinal degeneration, intellectual disability, ataxia, and heart disease and, recently, in autism spectrum disorder, schizophrenia, and epilepsy. The potassium voltage-gated channel subfamily H member 1 (KCNH1) gene encodes a member of the EAG (ether-à-go-go) family, which controls potassium flux regulating resting membrane potential in both excitable and non-excitable cells and is involved in intracellular signaling, cell proliferation, and tumorigenesis. KCNH1 missense variants have been associated with syndromic neurodevelopmental disorders, including Zimmermann-Laband syndrome 1 (ZLS1, MIM #135500), Temple-Baraitser syndrome (TMBTS, MIM #611816), and, recently, with milder phenotypes as epilepsy. In this work, we provide evidence that KCNH1 localizes at the base of the cilium in pre-ciliary vesicles and ciliary pocket of human dermal fibroblasts and retinal pigment epithelial (hTERT RPE1) cells and that the pathogenic missense variants (L352V and R330Q; NP_002229.1) perturb cilia morphology, assembly/disassembly, and Sonic Hedgehog signaling, disclosing a multifaceted role of the protein. The study of KCNH1 localization, its functions related to primary cilia, and the alterations introduced by mutations in ciliogenesis, cell cycle coordination, cilium morphology, and cilia signaling pathways could help elucidate the molecular mechanisms underlying neurological phenotypes and neurodevelopmental disorders not considered as classical ciliopathies but for which a significant role of primary cilia is emerging.

Fibrodysplasia ossificans progressiva in a young adult with genetic mutation: Case report

RATIONALE

Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal dominant disorder characterized by congenital skeletal deformities and soft tissue masses that progress into heterotopic ossification. Deformities of the great toes are distinctive and heterotrophic ossification usually begins in the first decade of the patient's life. Any invasive procedure could potentially trigger a flare and heterotopic calcification. The diagnosis is difficult and there is no effective treatment for FOP and the approximate life expectancy is 4 decades.

PATIENT CONCERNS

A 22-year-old male patient who had suffered from pain and movement limitations for 14 years. At the early stage of disease, the child underwent an operation on both thighs with a diagnosis of myophagism. He had serious stiffness and multiple bony masses with the characteristic bilateral hallux valgus deformity and microdactyly.

DIAGNOSES

The patient was diagnosed with FOP by the help of characteristic great toe malformations and widespread heterotopic ossification throughout the body. Deoxyribonucleic acid sequencing demonstrated that the patient had a de novo heterozygous mutation (c.617G>A; p.R206H) in activin A receptor/activin-like kinase 2.

INTERVENTIONS

We administered a co-therapy of glucocorticoids, NSAIDs to relieve pain, and montelukast for 2 months. Bisphosphonate (5 mg, intravenous) was used once.

OUTCOMES

At the follow-up 12 months later, the patient still felt low back pain sometimes and need take NSAIDs three times a week.

LESSONS

Clinicians and radiologists should realize the characteristic features of FOP and early diagnosis can prevent additional invasive harm to the patient.

Temple-Baraitser syndrome with KCNH1 Asn510Thr: a new case report

Temple-Baraitser syndrome (TMBTS; OMIM: 611816) is a rare developmental disorder characterized by severe mental retardation and anomalies of thumb and great toe with absence/hypoplasia of the nails. Here, we report an additional patient with TMBTS, review clinical and radiological features of previously reported cases and discuss mode of inheritance. The patient exhibited a pattern of anomalies: mild dysmorphic facial features with a wide open mouth, a thick vermilion border of the upper lip and downturned corners of the mouth; nails were absent on both great toes and thumb. Electroencephalogram showed a diffusely slow background. Whole genome sequencing identified one pathogenic missense mutation in KCNH1 (c. 1529 A > C; Asn510Thr) in this TMBTS patient. The mutation was also validated by Sanger sequencing.

Early Recognition of Fibrodysplasia Ossificans Progressiva-Important For the Clinician

Fibrodysplasia ossificans progressiva is a rare disorder of heterotopic ossification. Procedures like biopsy and surgery are known to be aggravating factors in promoting heterotopic ossification Clues to clinical diagnosis may therefore be a great advantage to treating orthopedician. Valgus deformity of great toe is an important diagnostic clue for treating physicians and thus aids in preventing the clinicians from subjecting the patients to unnecessary invasive and traumatic procedures. Hence clinical clues to early diagnosis are important in establishing the correct diagnosis and directing future management.

Two cases of Temple-Baraitser syndrome: natural history and further delineation of the clinical and radiologic phenotypes

This study reports on two individuals with Temple-Baraitser syndrome, manifesting typical hallux and pollex findings, global developmental delay, and seizures. In the five previous cases identified to date, consistent craniofacial and osseous characteristics have been observed. The children described herein exhibit minor differences within this phenotype and are older, highlighting the phenotypic variability and natural history of the clinical and radiographic findings.

Fibrodysplasia ossificans progressiva

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder of the connective tissue characterized by progressive disability as a result of extensive extra skeletal enchondral bone formation and malformed big toes which are often monophalangic. Occasional features include short thumbs, fifth finger clinodactyly, malformed cervical vertebrae and mild mental retardation. Beginning during childhood, FOP progressively immobilizes all the joints through adult life, rendering movement impossible. Currently, there is no effective prevention or cure for this debilitating disease. Since it has an autosomal dominant inheritance, our concern is to highlight prompt genetic counseling in the concerned families although many sporadic cases have also been identified.

Scalp nodules as a presenting sign of fibrodysplasia ossificans progressiva: a register-based study

BACKGROUND

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder characterized by progressive ossification of soft tissues. Clinical diagnosis is important because trauma from lesional biopsies can exacerbate the disease.

OBJECTIVE

We sought to evaluate the frequency of scalp nodules as the presenting manifestation of FOP.

METHODS

We describe 3 infants with FOP who presented with multiple neonatal scalp nodules. We reviewed all 43 cases of this disorder in the French FOP registry.

RESULTS

Scalp nodules were found in 40% of cases and usually represented the first manifestation of the disease. All 43 patients had characteristic skeletal malformations involving the great toes (n = 43), fingers (n = 12), and vertebrae (n = 3). Other abnormalities were cerebral malformations (n = 1) and alopecia (n = 2). Histopathologic analysis did not contribute to the differential diagnosis and was interpreted as cranial fasciitis in two patients.

LIMITATIONS

Our study was retrospective, and the presence or absence of scalp nodules was not always recorded.

CONCLUSION

Neonatal scalp nodules associated with a characteristic malformation of the great toes are a common presentation of FOP. Physicians should be aware that lesional biopsies can exacerbate the disease and must therefore be avoided. A diagnosis of classic FOP can be confirmed by molecular genetic studies.

Incomplete development of the nail of the hallux in the newborn

Between March and October 2008, the nails of 541 (252 females, 289 males) consecutively born neonates with an average age of 3.2 days were examined in the Neonatology Unit. Of these newborns with nail disorders, 36 were re-examined after a period that ranged from seven days to six months. The most frequent nail alteration was the incomplete development of the hallux nail, which was triangular - sometimes trapezoidal - shaped. This alteration, which had been previously reported in the literature as congenital hypertrophy of the lateral folds of the hallux, spontaneously regressed within one to three months in the infants re-examined. There was no associated inflammation or onychocryptosis at any time. The apparent hypertrophy of the nail folds seemed to be secondary to the lack of pressure of the nail lamina.

Prenatal diagnosis of a case probably with Oral-Facial-Digital Syndrome--Gabrielli type

We report here a case with microcephaly, preauricular pits, cleft lip-palate, hypertelorism, multiple frenula and preaxial polydactyly. The clinical picture overlaps with many syndromes, but it is mostly consistent with oral-facial-digital syndrome, Gabrielli type. There are no previously reported cases of this syndrome presenting also with microcephaly. On the other hand, it is hard to differentiate this clinical picture from Goldenhar syndrome (Oculo-auriculo-vertebral spectrum), and oculo-auriculo-fronto-nasal syndrome because of many overlapping features.

Short humerus: an additional antenatal sonographic feature of OFDS type II

The prevalence of skeletal dysplasia in the neonatal period is 2.4/10,000 births; it accounts for 1-2% of perinatal deaths, mainly stillbirths. A long bone measurement of less than -4 standard deviations is a definitive indication of skeletal dysplasia, whereas measurement between -2 and -4 standard deviations warrants detailed sonographic examination for other associated anomalies to arrive at a diagnosis. We report a case of oral-facial-digital syndrome type II that presented antenatally with polyhydramnios, short humerus, polydactyly, and duplicated thumb.

Correction of clawed hallux deformity: comparison of the Jones procedure and FHL transfer in a cadaver model

BACKGROUND

A clawed hallux is defined as extension of the first metatarsophalangeal (MTP) joint combined with flexion of the interphalangeal (IP) joint. Two operative procedures, the modified Jones procedure and flexor hallucis longus (FHL) transfer, are indicated for correction. The purpose of this study were to evaluate the overall effectiveness of these two procedures in correcting both the clawed hallux deformity and its mechanical consequences and to compare their effect on postoperative plantar pressures.

METHODS

The modified Jones procedure and FHL transfer were done on cadaver specimens that were tested before and after surgery in a specialized foot-loading frame. We quantified the angular correction of the MTP and the IP joints, as well as the plantar pressures under the head of the first metatarsal and the hallux.

RESULTS

Both surgeries were equally effective in correcting the angular deformity at the MTP and IP joints (p = 0.037 and 0.0020, respectively). A significant reduction in the plantar pressure (p = 0.015) beneath the first metatarsal was observed with both the modified Jones procedure and the FHL transfer. Overall, there was no significant difference between preoperative and postoperative pressures beneath the hallux (p = 0.5); however, for the FHL overpull group there was significantly less pressure beneath the hallux after surgery (p = 0.014).

CONCLUSIONS

The two surgeries produced similar results, but the FHL transfer does not require fusion of the hallux, which is considered an undesirable co-morbidity of the modified Jones procedure.

Abnormal first trimester screen in partial deletion of chromosome 6p21: a case-report

In this case-report we describe a 21-year-old primigravida with an abnormal first trimester screen: combined risk for Downs Syndrome was 1:90. Karyotype revealed 46,XX,del(6)(p21). Termination with Cytotec was offered because of the risk of congenital malformations and subsequent abnormalities associated with deletions in chromosome 6p. As to our knowledge no report has been written about the prenatal diagnosis of deletions on the short arm of chromosome six based on the first trimester screen. By publishing our experience we want to create awareness. This case-report shows the importance of combining prenatal screening with the biochemical tests, instead of only measuring nuchal translucency. It also shows the need for full karyotyping when invasive prenatal testing is done.

Difficulty in recognizing multiple sulfatase deficiency in an infant

We describe the difficulty in recognizing multiple sulfatase deficiency (MSD; Online Mendelian Inheritance in Man [OMIM] database No. 272200) in an infant. MSD is a rare autosomal recessive disorder that affects the posttranslational activation of various sulfatase enzymes. It is both biochemically and clinically variable. Currently, there are 12 known sulfatases in humans, and the clinical presentation of MSD is a unique composite of those individual enzyme defects. Here we report a black girl who presented with bilateral broad thumbs and great toes, both with angulation deformities at birth. Rubinstein-Taybi syndrome (OMIM No. 180849) was considered initially. The detection of inclusion bodies in her white blood cells at 37 months of age led to the appropriate diagnostic workups for lysosomal storage diseases. Elevation of urine mucopolysaccharides provided additional clues, and the fibroblast enzyme assays finally established the diagnosis. Broad thumbs and great toes are rare features of MSD, and to the best of our knowledge such a bilateral congenital anomaly with angulation deformities has never been reported before to be associated with MSD.

Pathomorphology and treatment of congenital anterolateral bowing of the tibia associated with duplication of the hallux

Congenital unilateral anterolateral tibial bowing in combination with a bifid ipsilateral great toe is a very rare deformity which resembles the anterolateral tibial bowing that occurs in association with congenital pseudarthrosis of the tibia. However, spontaneous resolution of the deformity without operative treatment and with a continuously straight fibula has been described in all previously reported cases. We report three additional cases and discuss the options for treatment. We suggest that this is a specific entity within the field of anterolateral bowing of the tibia and conclude that it has a much better prognosis than congenital pseudarthrosis of the tibia, although conservative treatment alone may not be sufficient.

Fibrodysplasia ossificans progressiva

A 2-year-old boy presented with low-grade fever and multiple progressive painful swellings over upper dorsal trunk and supraclavicular region with progressive stiffening of skin for the last 2 months. Examination revealed dysmorphic face, proximally placed thumb and bilateral hallux valgus. Hence, a diagnosis of Fibrodysplasia Ossificans Progressiva was entertained.

Island nail transfer in the treatment of macrodactyly of the great toe: a case report

Macrodactyly involving the great toe is difficult to treat when both the functional and cosmetic problems are addressed simultaneously. Partial resection of the distal phalanx is an easy way to reduce the length of the involved toe. However, there are cosmetic concerns with loss of the toenail. The authors report on a clinical case in which shortening and debulking of the toe was performed while preserving the hallux nail. The nail complex was transferred as an island flap to the dorsal aspect of the proximal phalanx. At the 1-year follow-up, the length of the reconstructed toe was significantly decreased, with a normal-looking nail.

[A rare shortening of the first metatarsus of the foot and its treatment with distraction arthrodesis]

Multiple toes may develop on the medial or lateral side of the forefoot or in its middle. This may involve duplication of only the distal phalanx or the whole hallux including the metatarsal. In a duplicated big toe, the phalanx to be maintained, because short muscles of the leg are attached to it, is usually localized medially. A rare case of dysplasia of the first metatarsus, following a resection indicated in childhood for a hallux triples, is described in a 20-year-old girl. In order to remove hallux insufficiency and an overloading of the middle metatarsals, the authors decided to carry out a one-stage prolongation of the first metatarsal, using an autologous tricorticcal graft collected from the pelvis and a dynamic compression plate. No surgical treatment of the middle metatarsals was indicated because a disproportionate, short foot would result. Both the subjective and objective status of the patient at 6 months after the operation showed that the non-standard prolongation procedure was correctly indicated and allowed for physiological loading of the foot and restoration of normal walking.

Variations in the insertion of the extensor hallucis longus muscle

Reports that describe abnormalities of the muscles and tendons of the leg and foot are important with regard to understanding the function of the lower limb and correlating these abnormalities with the clinical aspects. Variations in the insertion of the extensor hallucis longus muscle were studied in 60 adult human cadavers. Three different patterns of insertion were noticed. Pattern I (65%): the extensor hallucis longus muscle had a single tendinous insertion on the dorsal aspect of the base of the distal phalanx of the big toe. Pattern II (26.67%): the muscle terminated in two tendons. Pattern III (8.33%): the muscle terminated in three tendinous slips. Various sites of insertion of the extensor hallucis longus muscle were recorded other than the dorsal aspect of the base of the distal phalanx of the big toe. These were the dorsal aspect of the base of the proximal phalanx of the big toe and the capsule of the first metatarso-phalangeal joint or a connection with the tendon of the extensor hallucis brevis. The frequency of occurrence of lateral deviation of the big toe at the metatarso-phalangeal joint (hallux valgus) was recorded. It is suggested that the presence of these variations in the insertion of the extensor hallucis longus muscle may have a role in explaining its association with hallux valgus.

Broad thumbs and halluces with deafness: a patient with Keipert syndrome

Clinical, radiological, and audiological features are described in a boy whose condition closely parallels the profile of patients previously described with Keipert syndrome. This case represents the fourth report of this rare disorder.

Diagnosing acrocallosal syndrome

A 3-month-old male child presented with typical features of acrocallosal syndrome. He satisfies Courten's diagnostic criteria for acrocallosal syndrome.

[Lengthening of the IV metatarsal in the treatment of the shortened toe of the foot]

The author presents the results of surgical treatment of congenital shortening of the IV metatarsal in 3 girls. In 2 cases the defect was bilateral. A total of 5 feet were operated on the age of the patients at time of operation ranged from 10 years and 1 months to 16 years and 11 months. A one-stage procedure with the use of a Pumed mini-distraction device was performed. The fissure between the bone fragments was augmented with a bone graft from the fibula. It was harvested in such a way as to maintain internal cortical integrity. K-wire fixation of the bony fragments was applied for 7 weeks. Immobilization by means of a plaster cast was applied for 6 to 8 weeks. Follow-up ranged from 7 months to 3 years. In all cases an improvement of the finger shape and it's lengthening was noted, although in 2 cases lengthening wasn't complete. In one case it resulted from an axial deformity of the IV metatarsal, a sequel of early (5 weeks) removal of the K-wire.

Oral-facial-digital syndrome type II (Mohr syndrome): clinical and genetic manifestations

The oral-facial-digital syndromes (OFDS) represent a heterogenous group of disorders characterized by oral malformation, facial anomalies, and digital anomalies. Type II OFDS was reported by Mohr in 1941. Mohr syndrome is an autosomal recessive inherited disease characterized by median cleft lip, poly lobed tongue, absence of medial incisors, and polydactyly of hands and feet. Some other different expressive types of OFDS cases have been reported, and identified with 11 different clinical entities up to the present. Until now, only three cases of OFDS II in Japanese patients have been detected except for our patient. At this time, we observed a Japanese patient of Mohr syndrome with median cleft lip and tongue, hypertrophied frenula, absence of left medial incisor, and bilateral bifidity of great toe. Lip and tongue plasty was performed at 7 months after birth and toe plasty was done at 11 months with good results.

Lethal hydrops fetalis due to congenital dyserythropoietic anemia in a newborn: association of a new skeletal abnormality

Congenital dyserythropoietic anemias (CDAs) are a group of hereditary refractory anemias characterized by ineffective erythropoiesis, typical morphological abnormalities of erythroblasts, a low or no reticulocyte response, hyperbilirubinemia, and splenomegaly. A massive hydropic newborn born with a very severe anemia (Hb 4.8 g/dL), diffuse edema, hepatosplenomegaly, ascites, pulmonary edema and respiratory distress, and shortness and hallux varus deformity of the great toe of the right foot was diagnosed to have congenital dyserythropoietic anemia on the basis of the hematological (macrocytosis, anisopoikilocytosis, fragmented red cells and erythroblastosis in the peripheral blood, and erythroid hyperplasia with erythroblastosis and erythroblasts with double nuclei and thin chromatin bridges connecting these nuclei in the bone marrow) and serological (negative acidified serum lysis test and no agglutination with anti-i antibodies) findings. In this article the seventh case of neonatal congenital dyserythropoietic anemia presenting with a very severe (lethal) form of hydrops fetalis and a new (hallux varus) deformity of the great toe of the right foot is presented. Congenital dyserythropoietic anemia should be considered in the differential diagnosis of hydrops fetalis presenting with a very severe anemia and a skeletal abnormality of the great toe.

Complications after surgery of the hallux

The great toe is affected by many congenital and acquired conditions including arthritis, hallux valgus, and hallux rigidus and disease of the hallucal sesamoids. Many surgical procedures have been described for the treatment of these conditions. With the increased popularity of forefoot surgery comes the potential for complications even when the surgery is done meticulously by an experienced surgeon under well-planned conditions. When a complication occurs, it can present difficult and challenging problems. It is, therefore, important to recognize a complication early so it may be analyzed and treated successfully. When recognized, a plan should be developed to identify, quantify, control, and resolve the problem. The current review defines some common complications and treatment options. Several problems may exist at the same time. A solution addressing all aspects of the problem must be designed so as not to augment the presenting complications. Salvage operations and long-term treatment are included to provide a perspective on treatment of residual deformity. It is important to realize that there often are several solutions to a difficult problem. Many factors influence the surgeon's choice and implementation of a solution, but the ultimate outcome always depends on a well thought out plan.

A new syndrome with craniofacial and skeletal dysmorphisms and developmental delay

We report a 16-year-old boy with multiple craniofacial and skeletal dysmorphic features including brachycephaly, acrocephaly, hypertelorism, wide palpebral fissures, broad nose, anteverted nares, broad columella, long and smooth philtrum, thin upper lip, macrostomia, carp-like mouth, micrognathia, low-set and posteriorly angulated ears with small and abnormal pinnae, a low posterior hairline, a short neck, hypoplastic and widely-spaced nipples, multiple severe pterygia, an umbilical hernia, metatarsus varus, low implantation of the halluces, and delayed motor and language development. An MRI of the head showed bilateral frontal pachygyria but no sign of heterotopia. The unique features of our patient suggest that he represents a new syndrome.

Anterolateral tibial bowing and duplication of the hallux: a rare but distinct entity with good prognosis

Congenital anterolateral bowing of the lower leg usually is a symptom of (impending) fracture because of congenital pseudarthrosis. This article reports a case of anterolateral bowing of the lower leg that is characterized by spontaneous correction and combination with duplication of the hallux. A review of the literature showed 10 comparable cases. This article is the first report on the magnetic imaging of this entity and describes its differentiation from congenital pseudarthrosis.

Congenital hypertrophy of the lateral nail folds of the hallux: clinical features and follow-up of seven cases

Congenital hypertrophy of the nail folds of the hallux describes an abnormality of the periungual soft tissues of the big toe characterized by hypertrophy of the nail fold which partially covers the nail plate and is frequently associated with inflammation and pain due to an ingrowing nail. We describe the clinical picture and follow-up of seven patients with this abnormality. In three patients the affected toe showed an asymptomatic, dome-shaped, hypertrophic lip that partially covered the nail plate. Four patients had acute inflammatory changes due to toenail ingrowth, with considerable swelling and reddening of the hypertrophic lip that was painful on pressure. Topical treatment with steroids was useful to reduce inflammation and produced persistent remission in two patients. Follow-up showed a spontaneous disappearance of the hypertrophic nail fold in one of the seven patients. In two patients the hypertrophic lip partially regressed, but remained clearly visible, while in two patients it remained unchanged. In two patients surgical correction of the soft tissue abnormality was necessary due to painful nail ingrowth unresponsive to topical treatment.

Congenital absence of the lateral metatarso-phalangeal sesamoid bone of the human hallux: a case report

A case of congenital absence of the lateral metatarsophalangeal sesamoid bone of the hallux is reported, in a 47-year-old woman. The lateral sesamoid bone was absent on the right hallux, and extremely reduced on the left hallux. The normal intersesamoidean crest and both sesamoidean grooves of the metatarsal head were absent. Physical examination was normal, and no functional disturbance resulted from this variant. Only two previous cases have been found in the literature. It must be distinguished from a total resorption due to an infectious process, or from an absence due to surgical excision. This absence can be related to the general tendency of disappearance of the sesamoid bones within hominoid primates.

Thumb/hallux duplication and preaxial polydactyly type I

It was recently shown that hand postaxial polydactyly differed from foot postaxial polydactyly. The aim of this work was to test whether thumb and hallux duplication also had different clinical and epidemiological characteristics, depending on limb involvement. We studied 920 newborn infants with first digit duplication, ascertained among 3,444,374 births by the Latin-American Collaborative Study of Congenital Malformations (ECLAMC), from 1967 to 1995. Since biphalangeal thumb duplication or hallux duplication can occur in families with triphalangeal thumb or polysyndactylous propositi, these groups were also analyzed. The 715 isolated (nonsyndromal) cases (prevalence 2.08 per 10,000) were subdivided into five groups: thumb duplication (N = 568; prevalence: 1.65/10,000); hallux duplication (N = 82; prevalence: 0.24); thumb and/or hallux duplication plus syndactyly (polysyndactyly) (N = 37; prevalence: 0.11); triphalangeal thumb (N = 24; prevalence: 0.07), and thumb duplication plus hallux duplication (N = 4; prevalence: 0.01). Both thumb and hallux duplication groups showed a significant excess of males, and right sidedness was also more frequent in both of them, though without statistical significance for hallux duplication. Thumb duplication was more often unilateral (94.7% versus hallux duplication of 81.5%), and its prevalence was higher in Bolivia (3.37/10,000) than in the other 10 Latin-American countries included (1.62/10,000). In a subseries of 405 preaxial polydactylies with matched controls, a logistic regression analysis showed that birth weight and gestational age had an effect on the calculated risk of having an infant with thumb duplication, while first trimester vaginal bleeding had only a borderline effect. None of the polydactyly groups showed abnormal values for twinning, perinatal mortality, ethnicity, maternal education, parental ages, parity, parental subfertility, or consanguinity. There were 70/405 familial cases. Their pedigrees were compatible with autosomal dominant inheritance with a 9% penetrance for thumb duplication and hallux duplication and a 70% penetrance for triphalangeal thumb and polysyndactyly. Inheritance of thumb duplication and probably the untested inheritance of hallux duplication were also compatible with a four-locus multiplicative model. The observed differences in laterality, geographical distribution, birth weight, gestational age, and first trimester vaginal bleeding between thumb duplication and hallux duplication groups suggested that apparent preaxial polydactyly type 1 is a causally heterogeneous group.

Blepharophimosis, hypoplastic radius, hypoplastic left heart, telecanthus, hydronephrosis, fused metacarpals, and "prehensile" halluces: a new syndrome?

We report on the prenatal ultrasound and postnatal findings in an infant born to a healthy, nonconsanguineous couple. The infant had microcephaly, telecanthus, blepharophimosis, cleft palate, micrognathia, abnormally modeled ears, hypoplastic left heart, hypoplastic radii and ulnae with radial subluxation, pseudoarthrotic distal humeri, fused metacarpals, tibial bowing, unusual feet with long halluces, hydronephrosis, patent urachus, abnormal electroencephalogram, and normal karyotype. To our knowledge, this combination of anomalies has not been recognized previously and may represent a new condition.

[Hallux varus congenitus]

INTRODUCTION

The congenital hallux varus is a rare hereditary deformity of the big toe, which often is combined either with polydactylia or with systemic deformities of the skeleton. The congenital hallux varus can be easily diagnosed clinically. The X-ray shows the ossified bony elements and provides information about the shape and number of the digits as well as their axial deviation. An operative treatment is required. So far a standardized surgical technique has not been accepted for all types of hallux varus.

METHODS

The correction of the bony structures and soft tissues is planned by means of preoperative scetches. The amount of correction depends on the degree of the deformity. As consequence of the reorientation of the first ray a soft tissue flap has to be planned and prepared for wound closure which otherwise would need larger grafts.

RESULTS

Based on this series the clinical and radiological appearance of the congenital hallux varus are discussed. The operative treatment is explained step by step illustrated by photographs as well as planing scetches. Our procedures are compared to other operative methods reported in the literature.

CONCLUSIONS

There are no diagnostic problems with the hallux varus deformity. For therapy surgery is mandatory and recommended between 9 and 24 months of age. For microsurgical preparation and correction of the deformity planning of all surgical steps and alternatives is advocated, this allows for good functional and cosmetic results.

Lengthening of short great toes by callus distraction

We lengthened seven first metatarsals in four patients with short great toes by callus distraction using an external fixator. Good clinical and cosmetic results were obtained. Bone lengthening is effective in patients with short great toes not only for cosmesis, but also to relieve pain and callosities on the plantar aspect of the second and third metatarsal heads. Excessive lengthening of the first metatarsal resulted in limitation of the range of movement of the metatarsophalangeal joint of the great toe. To prevent this the amount of lengthening should not exceed 40% of the preoperative length of the metatarsal.

HOX gene links limb, genital defects

The HOX gene family has helped to unlock the intricacies of development in animals from flies to mammals, but its role in humans has been a mystery. Now the second human HOX gene mutation has been found in a Michigan family. It causes abnormalities in both limbs and genitals—and raises some intriguing evolutionary ideas.

Concomitant syndactyly and polydactyly in a pediatric foot

Syndactyly and polydactyly in a child may warrant surgical treatment to avert resultant emotional and psychologic problems. The authors present a unique case report of a bilateral polydactyly of the hallux and bilateral syndactyly of the second and third toes in a normal 6-year-old Hispanic female. The article will discuss the surgical management of these problems, using the skin harvested from resection of the extra hallux for the adjacent side of the lesser toes after desyndactyly.

Multiple lower limb osteophytosis with macrodactyly: a case report

A 39-year-old woman with restriction of movement and macrodactyly of the great toes was found to have severe juxta-articular multiple osteophytosis of the lower limbs. The pathogenesis of this unusual condition is unknown. It may be a variant of diffuse idiopathic skeletal hyperostosis.

Use of titanium grommets in silicone implant arthroplasty of the hallux metatarsophalangeal joint

Double-stem silicone implants protected by titanium grommets were placed in the hallux metatarsophalangeal joints of 32 patients (47 feet). All patients had a painful destroyed joint and most were women. Three patients (six feet) were lost to follow-up. Nineteen patients had a diagnosis of rheumatoid arthritis (25 feet) and 10 had degenerative joint disease (16 feet). The average age for the group was 57 years and the average follow-up was 51 months (range, 34-76 months). Twenty patients (30 feet) were completely satisfied with their result. Eight patients (10 feet), all with rheumatoid arthritis, had some minor postoperative complaints, usually involving the lateral toes. Two patients (three feet) in this group had no pain, but would have preferred more hallux motion. One patient with rheumatoid arthritis (one foot) had a poor result due to implant removal for deep sepsis. Radiographic analysis of these patients showed no evidence of implant fracture and the implant composite appeared to be well tolerated by the surrounding bone in which it was placed. When compared with another, similar group of patients in whom grommets were not used, this implant appeared to be much more stable, as there was significantly less evidence of radiolucency seen around those implants protected by the grommets. It appears that the titanium grommets may protect the silicone implant and may help provide a longer life for the silicone implant.

Biomechanical assessment of a new tenodesis for correction of hallux varus

Each of six below-the-knee amputation specimens were transfixed to a wooden block and mounted to a jig on an amputee testing device preloaded with 5 N applied to the proximal phalanx and displaced at a constant rate of 2 mm/min. Load displacement curves were generated for the intact joint and after sequential incisions of the lateral capsule, the adductor hallucis, and the lateral slip of the flexor hallucis brevis tendon, which caused varus dislocation of the hallux. An extensor hallucis brevis tenodesis was performed after the varus dislocation. Division of the lateral capsule, the adductor, and the flexor brevis reduced the force required to displace the hallux by 42.2%, an additional 25.2%, and a further 14.2%, respectively. Use of the extensor hallucis brevis tenodesis restored the load displacement curves to that of the normal joint. We conclude that the extensor hallucis brevis tendon may be useful as a tenodesis for reconstructing the deformity of acquired hallux varus.

Unilateral duplication of the great toe with anterolateral tibial bowing

A syndrome consisting of unilateral duplication of the great toe in association with anterolateral bowing of the tibia is described. Patients with this syndrome have significant pedal difficulties after surgical management, but the tibial bowing spontaneously resolves without treatment. Tibial shortening is noted relative to the fibula. Associated clinodactyly and dysharmonic maturation of carpals and metacarpals are also seen. Current data are most consistent with a developmental rather than a genetic etiology.

Results of hallux varus correction using an extensor hallucis brevis tenodesis

We have used an extensor hallucis brevis tenodesis procedure to treat symptomatic hallux varus in six patients (five women and one man). Indications for this procedure include the presence of flexible metatarsophalangeal and interphalangeal joints and the absence of arthritis. In this group (mean age, 47 years; range, 18-65 years), hallux varus followed correction of hallux valgus deformity in five patients and traumatic dislocation of the hallux in one patient. Excellent correction was noted and maintained in all patients at a mean interval of 28 months (range, 24-32 months) after surgery. Despite a slight decrease in dorsiflexion following surgery (average, 10 degrees), there were no additional complications noted, and the mean American Orthopaedic Foot and Ankle Society rating score improved from 61 to 85 after surgery.

A large Turkish kindred with syndactyly type II (synpolydactyly). 1. Field investigation, clinical and pedigree data

A very large Turkish family with syndactyly type II (synpolydactyly (SPD)) is described, which originated from and is mainly concentrated in the village of Derbent, Afyon. The kindred consists of 425 subjects over seven generations, of whom 182 are affected. It appears that a founder effect in this village has led to this extensive kindred. This condition is inherited as an autosomal dominant trait with variable expressivity and an estimated penetrance of 96%. Penetrance is different between the upper (96%) and lower (69.5%) extremities. No excess of affected males or females or other associated features were documented in this condition. Variations in the involvement of one or both hands, upper or lower extremities, bone and soft tissue, as well as variation in the affected subjects of two successive generations were documented. We also noted that metacarpal and metatarsal involvement and middle phalangeal hypoplasia of the feet are the consistent features of SPD and, therefore, should be considered as characteristic of this phenotype. We observed four different phenotypes in various branches of the Derbent kindred: (1) subjects presenting typical features of SPD; (2) subjects exhibiting both pre- and post-axial polydactyly simultaneously; (3) persons manifesting postaxial polydactyly type A; and (4) subjects born to two affected parents with severe hand and foot deformities that have not been previously described in any other SPD families (that is, homozygotes). A total of 27 affected offspring were born to two such affected parents, of whom seven are expected to be homozygous for the SPD gene. This group is presented in an accompanying paper in this issue of the Journal. A molecular study is currently under way to identify the chromosomal location of the defective gene.

A metallic hemiarthroplasty resurfacing prosthesis for the hallux metatarsophalangeal joint

Two-hundred seventy-nine arthritic hallux metatarsophalangeal joints treated surgically with a metallic resurfacing hemiarthroplasty over a 40-year period were reviewed. The implant, which is made available in three evenly graded sizes, is designed to replace only the articular surface of the proximal phalanx, with minimal resection of bone stock. The pathologic indications for surgery included classical hallux rigidus, rheumatoid arthritis, and degenerative changes associated with hallux valgus and bunion deformity. Follow-up at 8 months to 33 years after surgery revealed good or excellent clinical results in 95%. The time to follow-up was in excess of 5 years in 101 (36%) of the procedures, beyond 10 years in 62 (22%), and longer than 20 years in 23 (8%). Unlike other available surgical options for this debilitating condition, biomechanics of the hallux metatarsophalangeal joint remained unaffected and problems associated with prosthetic wear or mechanical failure were not encountered.

Preaxial brachydactyly with abduction of thumbs and hallux varus: a distinct entity

We describe a father and his daughter who had a unique pattern of preaxial brachydactyly, and unusual facial appearance. Both had short broad abducted thumbs and halluces. The second digits of both hands were also short and broad and those of feet were medially angulated. The radiographic findings were short first metacarpals and first metatarsals and hypoplastic phalanges of first two digits of hands and feet. A similar pattern of brachydactyly was described by Christian et al. [1972: Am J Hum Genet 24:694-701] and Mononen et al. [1992: Am J Med Genet 42: 706-713]. Our patients differ from those described by Christian et al. in that they did not have any mental retardation and from those of Mononen et al. by the absence of short stature and epiphyseal and metaphyseal changes. The heterogeneity of this new type of brachydactyly remains to be resolved.