A classification of cleft hands, based on clinical findings: theory of developmental mechanism

A comprehensive functional classification of cleft hand: The DAST concept

Context:

Phenotypic expressions of the congenital cleft hand are variable and might baffle even the experienced as to the choice of surgery. The morphological parameters defining the anomaly dictate not only the functional capacity of the anomalous hand but also the degree of possible surgical restoration. Despite a large number of classifying systems available, none encompass all the relevant issues.

Aims:

The purpose of this work is to present an all-inclusive and universally acceptable classification of the deformity which would graphically represent the entire gamut of possible presentations; principal and associated. Furthermore, based on such staging, the choice of surgical procedure and the stages of surgical intervention can be standardised to ensure the best results for the patient.

Patients and Methods:

This study is based on a series of 27 patients with a total of 38 cleft hands.

Results and Conclusions:

The necessity to include and to assess all determinants of function and complexity in these hands to standardise the choice of management, gave rise to the DAST system of classification; an acronym for all the morphological determinants of the anomaly (D = Digits missing, A = Associated anomalies in the hand, S = Site of cleft, T = Functional state of the Thumb). Numerical values were assigned to each component in increasing order of complexity. Score for each determinant as well as the aggregate score indicates the degree of complexity in a graphic manner. The DAST classification has a predictive value in choice of procedure and prognosticating surgical outcomes.

Description of Congenital Hand Anomalies: A Personal View

A series of four congenital hand cases exhibiting central clefting are presented. The cases are morphologically similar and exhibit characteristics of both symbrachydactyly and central longitudinal deficiency. The cases demonstrate difficulties in classification by either the IFSSH classification system or the JSSH modification of it. An alternative descriptive approach to classification is suggested.

Over 20-year follow-up of Miura reconstruction of cleft hand

Several techniques have been described for cleft hand closure and web space reconstruction in patients with central deficiency; however, long-term documentation of results is rare. We present a 23-year follow-up of a patient who underwent the Miura procedure for a Manske type IIb cleft hand exhibiting long-term aesthetic and functional success. In addition, early skin flap necrosis and late web space contracture, which have been seen after the Snow-Littler procedure, did not occur in this case.

A new documentation system for congenital absent digits

BACKGROUND

Congenital absent digits continue to be described by many confusing terms and are currently classified in categories I, V, and VI of the International Federation of Societies for Surgery of the Hand classification and seven subclassification systems. Very few classification systems provide any logical basis for surgical reconstruction. The purpose of this study was to develop a simple alphanumerical documentation system to reproducibly describe the morphological or radiographic appearance of congenital absent digits and facilitate communication of these childrens' hand anomalies from one hand surgeon to another.

METHODS

Dorsal and palmar photographs and PA radiographs of 235 hands in 204 children born with congenital absent digits over a 15-year period were analyzed to determine which digital rays were missing and their level of absence. Each hand can be described by three letters, R (radial), C (central), and U (ulnar), as well as numbers 1-5. The first letter and number designate which rays are missing and the second and third letters and numbers designate which rays remain present.

RESULTS

There are 15 morphological phenotypes of congenital absent digits. The three most common phenotypes are U4R1 (a thumb but absence of all four fingers), R1U4 (absent thumb), and R5 (aplastic hand).

CONCLUSIONS

This new documentation system allows hand surgeons to describe the simple morphological or radiographic appearance of congenital absent digits; incorporates all the previous subclassification systems that have attempted to describe congenital absent digits in radial, central, and ulnar deficiencies, symbrachydactyly, and congenital constriction ring syndrome; and has subsequently allowed the development of an algorithm which predicts whether conventional or microsurgical reconstruction is indicated for each specific phenotype.

[Central ray deficiency of the hand]

Cleft hand is an uncommon congenital malformation, which is defined as a deficiency of the central part of the hand. It results from the absence or alteration of development of the central rays. Although the function of the hand is often excellent, the cosmetic appearance drives parents to seek consultation. The goal of this article is to define the different factors that dictate the classification of this anomaly and to facilitate choosing among many surgical procedures. Treatment improves aesthetic aspect of the hand and maintains excellent function. A retrospective review of 33 operated cases is presented.

Occurrence of central polydactyly, syndactyly, and cleft hand in a single family: report of five hands in three cases

Central polydactyly, syndactyly, and cleft hand are categorized separately in the International Federation of Societies for Surgery of the Hand classification. However, some investigators have proposed that these malformations should be classified into a single category: abnormal induction of finger rays. In this article, we report 5 hands with central polydactyly, syndactyly, and cleft hand in 3 patients from the same family and discuss the phenotypes in each hand.

Congenital failure of formation of the upper limb

This article provides an overview of the various classification systems for radial longitudinal, central longitudinal, and ulnar longitudinal deficiencies. It looks specifically at radius deficiency, hypoplastic thumb, index finger pollicization, narrowed thumb web, forearm-elbow deformities, and hand abnormalities. Various surgical approaches to these conditions and their results are explored. The authors conclude that longitudinal failure of formation deformities comprises a substantial portion of the anomalies of the upper limb. Although much of the past and current congenital hand literature has been devoted to these conditions, they continue to be a reconstructive challenge to hand surgeons involved in their care.

[Cleft hand: a review of 33 cases and new ideas about classification]

Cleft hand is an uncommon congenital malformation, which is defined as a deficiency of the central part of the hand. It is the result of the absence or altered development of the central rays. The aim of treatment is to optimise the function of the hand at a young age and to improve its aesthetics. A retrospective review of 33 cases is presented and, with reference to their treatment, ideas about the classifications of cleft hand are discussed. The various anomalies seen and the management for each type of cleft hand are presented.

Early morphological changes leading to central polydactyly, syndactyly, and central deficiencies: an experimental study in rats

PURPOSE

Various combinations of central polydactyly, syndactyly, and cleft hand have been frequently observed in the individual hands and feet in the same patients. Little is known, however, about the early changes of abnormal induction of digital rays during limb development. To determine the early changes and process of formation of central polydactyly, syndactyly, and cleft hand, we experimentally induced these anomalies in the hind limbs of rat embryos and discussed the relationship among these abnormalities.

METHODS

Inbred WKAH/Hkm rats were used for this study. Pregnant females were treated with busulfan at embryonic day (E) 11. The embryos were removed at E12 to E21 and stained with alcian blue and alizarin red S. The abnormal changes in the treated embryos' hind limbs were observed with a microscope.

RESULTS

The edges of the footplates were irregular, and their growth was reduced at E14. By E15, abnormal clefts in the distal edge were present that disrupted the central digits (2 to 4) of the footplates. Because of these abnormal clefts, the digital rays were bent or branched, and the neighboring interdigital spaces were narrowed. These changes led to central polydactyly, syndactyly, and central deficiencies.

CONCLUSIONS

These findings show that central polydactyly, syndactyly, and central deficiencies have the same early morphological changes: abnormal clefts in the central part of the footplate.

Clinical features and teratogenic mechanisms of congenital absence of digits

To have a better understanding of classification of congenital hand anomalies, clinical features and teratogenic mechanisms of congenital absence of digits including ulnar and radial deficiencies, cleft hand, symbrachydactyly and constriction band were reviewed. There seemed to be four different teratogenic mechanisms of congenital absence of digits. Ulnar and radial deficiencies have the same clinical features and the cause of these deficiencies is closely related to a deficit of mesenchymal cells in the limb-bud due to impairment before the formation of the limb-bud. Cleft hand, central polydactyly and osseous syndactyly were induced by the same treatment at the same developmental stage in rats. Roentgenograms of the clinical cases and skeletal changes of the anomalies in rats appear to demonstrate that cleft hand formation proceeds from osseous syndactylies and central polydactylies. The teratogenic mechanism of a cleft hand seemed to be failure of induction of digital rays in the hand plate. The sequence of anomalies from brachysyndactyly, or the atypical cleft hand, to the congenital amputation, can be regarded as equivalent to the category of transverse deficiency that is bony dysplasia of the hand. Congenital constriction ring syndrome appears after the formation of the digital rays.

Genotype-phenotype correlations in mapped split hand foot malformation (SHFM) patients

Split hand foot malformation (SHFM) also known as central ray deficiency, ectrodactyly and cleft hand/foot, is one of the most complex of limb malformations. SHFM can occur as an isolated malformation or in association with other malformations, as in the ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome and other autosomal dominant conditions with long bone involvement, all showing variable expressivity and reduced penetrance. The deficiency in SHFM patients can also be accompanied by other distal limb anomalies including polydactyly and/or syndactyly. This variability causes the phenotypic classification of SHFM to be far from straightforward and genetic heterogeneity, with at least five loci identified to date, further complicates management of affected patients and their families. Although genotypic-phenotypic correlations have been proposed at the molecular level for SHFM4 patients who have mutations in the P63 gene, phenotypic correlations at the chromosomal level have not been thoroughly documented. Using descriptive epidemiology, Chi square and discriminant function analyses, our laboratory has identified phenotypic patterns associated with the mapped genetic SHFM loci. These findings can assist in classification, provide insight into responsible developmental genes and assist in directing mapping efforts and targeted genetic testing, resulting in more accurate information for family members in the clinical setting. Comparison with relevant animal models is discussed.

Radial shift of the ulnar fingers: a new technique for special cases of longitudinal central deficiency

Treatment of central longitudinal deficiencies is well defined, with different techniques established for the classical clefts. However, none of these techniques is easily applied to the treatment of very deep clefts accompanied by a significant divergence of the metacarpal bones. In such cases, the results of current techniques are disappointing. We propose a new technique of "Translocation in the Radial direction of the Ulnar Finger(s)" (TRUF) by intra-carpal osteotomy. The results are illustrated in three clinical cases. The TRUF operation allowed closing of the cleft, alignment of the metacarpal bones and preservation of carpometacarpal mobility. When necessary, a metacarpal synostosis may be treated at the same procedure.

Analysis of anatomic variations in cleft hands

PURPOSE

This study presents an overview of the clinical and x-ray findings observed in 54 cleft hands of 31 patients. The emphasis was on a detailed analysis of typical malformation-associated x-ray patterns such as aplasia and synostosis, with findings arranged as a function of cleft location and of the Manske and Halikis classification.

METHODS

The charts and radiographs of 31 patients with 54 cleft hands were reviewed retrospectively and compared with data reported in the literature. Important clinical and x-ray findings as well as the typical morphology of cleft hands were analyzed. Cleft hands were differentiated according to their location and according to the Manske and Halikis classification. In the different locations the deformities were arranged in teratologic sequences.

RESULTS

In cleft hands syndactylies were seen in 30 of the 54 hands, most commonly between the ring and the small finger. In 3 hands polydactylies were noted. Analysis of the x-ray morphology showed 2 typical patterns: aplasia and synostoses. Location-specific teratologic sequences showed that radial cleft hands were bilateral more frequently and were associated significantly more frequently with cleft feet. Aplasias predominated in radial cleft hands, whereas synostoses were more common in central cleft hands. In terms of the Manske and Halikis classification the unilateral cleft hands often corresponded to type I whereas bilateral cleft hands with cleft feet mainly were type IV and type V deformities. Cleft hands with synostoses often were seen in types I to III whereas cleft hands with aplasias were classified most frequently as type V.

CONCLUSIONS

Analysis of the patients' clinical data and x-rays showed differences between radial and central cleft hands, as well as between the different Manske and Halikis types.

Cleft hands with six metacarpals

PURPOSE

The purpose of this study was to identify children with cleft hands whose radiographs showed metacarpal polydactyly with 6 metacarpals to support the hypothesis that cleft hand develops not as a result of a longitudinal failure of formation but through a process of central polydactyly and osseous syndactyly.

METHODS

We screened the hand radiographs of all children with a transverse or longitudinal deficiency of the upper limb and identified 8 children with cleft hands containing 6 metacarpals.

RESULTS

Six cleft hands had a missing middle finger and consisted of a thumb and index finger separated from the ring and small fingers by a V-shaped central cleft. Two children had a more severe form of cleft hand with absence of both the index and middle fingers but presence of 6 metacarpals.

CONCLUSIONS

These 8 cleft hands containing 6 metacarpals showed progression of polydactyly of the middle finger and osseous syndactyly between the 2 middle finger metacarpals and the adjacent index and ring finger metacarpals. This contradicts a longitudinal failure of formation mechanism and supports the alternative hypothesis that cleft hand, polydactyly, and syndactyly develop through a similar teratogenic mechanism. The 2 cleft hands that had more severe suppression of the index and middle fingers yet had 6 metacarpal polydactyly provided confirmatory evidence that both typical cleft hands and the more severe manifestations of cleft hand with absence of multiple digits develop through a similar failure of induction mechanism.

Congenital anomalies: a 25-year overview

Expansion of the discipline of hand surgery and heightened interest in congenital problems have resulted in major advances in the treatment of congenital hand anomalies over the past 25 years. Increased experience with congenital anomalies of the hand has expanded the hand surgeon's knowledge of patterns and relationships between different anomalies resulting in new methods of classification and more logical approaches to treatment. The principles of treatment of the more common anomalies, such as syndactyly, established by prior generations of hand surgeons have been refined in details of technique. New technologies, such as distraction lengthening and free vascularized transfers, have allowed the surgeon to treat new problems and old problems in new ways. In spite of our successes, much remains to challenge hand surgeons in this new millennium, especially in the construction of joints and the expanding field of fetal surgery.

Congenital anomalies of the hand. The Asian perspective

To have a better understanding of teratogenic mechanisms of congenital absence of digits, ulnar and radial deficiencies, cleft hand, and symbrachydactyly were analyzed in clinical cases. The same anomalies were induced in rat fetuses by busulfan, and their characteristics were investigated. The formation process of longitudinal deficiency also was observed histologically. There seemed to be 4 teratogenic mechanisms of congenital absence of digits. Ulnar and radial deficiencies have the same clinical features, and the cause of these deficiencies is related closely to a deficit of mesenchymal cells in the limb bud caused by the impairment before the formation of the limb bud. Cleft hand, central polydactyly, and osseous syndactyly were induced by the same treatment at the same developmental stage in rats. Cleft hand formation process from osseous syndactylies and central polydactylies was supposed. The teratogenic mechanism of cleft hand seemed to be failure of induction of digital rays in the hand plate. The sequence of anomalies from brachysyndactyly, or the atypical cleft hand, to the transverse deficiency can be regarded as equivalent to the category of bony dysplasia of the hand. Congenital constriction ring syndrome does appear after the formation of the digital rays.

Surgical classification of central deficiency according to the thumb web

A classification for congenital central deficiency is presented. In contrast to previous classification schemes, this proposed classification is based on the characteristics of the thumb web, which are more important to the function of the hand than are the central deficiency features. Five progressive narrowings of the thumb web are identified: normal web (type I), narrowed web (type II), syndactylized web (type III), merged web (type IV), and absent web (type V). Forty-six central-deficient hands were classified and reviewed. The progressive narrowing of the thumb web correlated with progressive severity of the central defects. The proposed classification system guides and directs surgical recommendations.

[Median clefts of the hand. Classification and therapeutic indications apropos of 29 cases]

Based on a series of 29 patients with median clefts of the hand (29 hands), the authors define the place of this malformation, its various clinical features and the therapeutic indications. The series consists of 13 boys and 7 girls, 9 bilateral cases and 11 unilateral cases. Involvement of the feet was observed in 9 cases. Several children also presented other malformations. 16 children were operated (22 hands). Two types of technique were used: simple closure of the cleft (Barsky's operation) and transposition of the index finger according to the Snow-Littler or Miura-Komada techniques. All operated patients were reviewed with a follow-up of more than one year and the results were assessed in terms of three criteria: overall use of the hand, thumb-index finger pinch grip, aesthetic appearance. The authors propose a new classification of median clefts of the hand based on examination of this series of 20 children: simple clefts with more or less complete absence of the middle finger, complex clefts with syndactyly (especially I and II), transverse bone polydactyly, extensive clefts with severe aplasia of the radial segment of the hand. Clinical and radiological examination confirm the experimental studies by Ogino. Barsky's operation gives satisfactory results in simple forms with parallel fingers. Translocation of the index finger to the base of the 3rd metacarpal is necessary in the presence of divergent fingers and syndactyly. Median clefts of the hand are very distinct from median aplasia, which is always unilateral, with no familial nature and no involvement of the feet and which can be classified together with brachysyndactyly. Each case must be studied before deciding treatment, as functional adaptation is always remarkable. The least favourable surgical results are observed in forms with abnormal position of the index finger (malrotation syndactyly). Lastly, the Snow-Littler operation is not devoid of complications.

Cleft hand, syndactyly and hypoplastic thumb

The clinical features of 58 patients with typical cleft hand were examined and compared with 86 patients with syndactyly between the long and ring fingers, 27 patients with syndactyly between the ring, little and other fingers, 53 patients with hypoplastic thumb and 100 patients with symbrachydactyly. The clinical findings of the typical cleft hand resembled those of syndactyly. There were two unusual cases of typical cleft hand associated with hypoplastic thumb, congenital heart anomalies and absence of the axial triradius. One of these also had cleft lip and palate. The critical embryonic period of the heart anomaly is early, while that of the cleft lip and palate is late. These findings suggest that an embryo with typical cleft hand and hypoplastic thumb results from impairments at two different times in the early embryonic period.

Teratogenic relationship between polydactyly, syndactyly and cleft hand

Several investigators have suggested that polydactyly, syndactyly and cleft hand might have arisen from a common teratogenic mechanism. To confirm this hypothesis, 75 hands with these anomalies were analysed. Advanced cases with central polydactyly or osseous syndactyly in which the fusion area extends as far as the proximal phalanx and metacarpus are identical to typical cleft hand. The author has induced the same deformities using myleran in rat foetuses. The clinical features of these anomalies in rats were the same as those in clinical cases and the critical periods of these anomalies were also the same. The findings suggest that these hand anomalies may appear in human beings when the same teratogenic factor acts on the embryo at the same developmental period and that they should belong to the same teratogenic entity.

Congenital hand anomalies in Japan: a family study

During the 20-year period from 1968 to 1987, 1024 patients with congenital anomalies of the hand from 1000 Japanese families were examined in our clinic. Of these patients, 204 had relatives with limb anomalies. While postaxial polydactyly showed a 33% level of familial recurrence, symphalangism and Kirner's syndrome showed about 23% recurrence, syndactyly 18%, radioulnar synostosis 9%, radial ray deficiency 8%, cleft hand 7%, and duplicated thumb 5%. None of the relatives had ulnar deficiency or symbrachydactyly.

[Clinical anatomo-pathologic and surgical considerations in type III central polysyndactylia of the hand (systemization and classification of lesions)]

Central polysyndactyly type III of the hands is a very rare and complicated malformation, since it shows a great number of anatomic and functional lesions. Seven persons belonging to an ethnic original group living in Trapani, in Western Sicily, have been the topic of a very deep and careful study; four of them have been operated on both sides. Our clinical research has allowed us to build up a Pedigree of the elements suffering from the malformation (showing autosomic dominant character) dating back to the beginning of the nineteenth century. The pedigree includes one hundred and fifteen persons of whom seventy healthy and forty five afflicted with central polysyndactyly type III. Numerous operative techniques have been used to face the anatomic, functional and aesthetic difficulties we have found.

Central ray deficiency of the hand. Operative treatment and results

Fifty nine hands were studied in 42 patients with central ray deficiency. Thirty one of the hands were treated surgically and this enabled analysis of the soft tissue abnormalities that were not constant throughout the group, requiring a sub-division of the usual classification. Four major surgical procedures and two minor procedures are described and the importance of creating a substitute for the deficient transverse intermetacarpal ligament and correction of any intrinsic muscle imbalance is emphasized. Of the 31 hands treated all but three gained useful grip and all but two gained useful pinch grip and a satisfactory range of motion. From the cosmetic standpoint all were satisfactory except for one case with a hypertrophic scar and six cases with overlapping of the fingers when grasping.

Cleft hand and central polydactyly in identical twins: a case report

Four hands of a pair of identical twins demonstrated manifestations of both cleft hand deformity and central polydactyly, supporting the concept that a common etiological mechanism is involved in the development of these anomalies.

Congenital hand anomalies, and their association with other congenital abnormalities

Congenital abnormalities of other parts occurring in patients with congenital abnormalities of the hand were studied. Hands and feet often showed similar anomalies, but there were cases in which the hands and feet had different kinds of deformity. Anomalies of the internal organs were associated with anomalies of the thumb. Cleft lip and palate occurred in combination with syndactyly, split hand, preaxial polydactyly and construction ring syndrome. Combined anomalies may be the result of a genetic or environmental factor interfering with parts developing during the same critical period. The critical period and probable pathogenesis are discussed and the conclusion reached that mesenchymal necrosis, abnormal distribution of mesenchyme and tissue necrosis after mesenchymal condensation may be the pathological changes which lead to abnormal development of the hand.

Congenital central ray deficiency in the hand- a survey of 59 cases and subclassification

Eighty-nine hands were studied in 59 patients with central ray deficiency. A subclassification into two subgroups was established based on the clinical and radiological findings-subgroup I: typical type and subgroup II: (atypical type) with type a, syndactylous type, and type b, polydactylous type. In subgroup I, the sequential severity of deficiency ranged from a partial defect of phalanges of the middle finger to a monodigit hand. The central digital elements were fused to adjacent digital rays in subgroup II-type a. Supernumerary bony elements were seen in subgroup II-type b. The close relationship between central ray deficiency, syndactyly, and polydactyly was discussed from the standpoint of development of the hand. The classification of central ray deficiency into the longitudinal deficiency category of the International Classification of Congenital Limb Malformations was recommended.