Developmental biology and classification of congenital anomalies of the hand and upper extremity

The Impact on Families of Children With Congenital Upper Extremity Differences

PURPOSE

To investigate the impact on caregivers of caring for a child with congenital upper extremity differences.

METHODS

In this cross-sectional study, caregivers of patients enrolled in the multi-institutional Congenital Upper Limb Difference (CoULD) registry were contacted. Demographic information and the Impact on Family Scale (IOFS), a validated measure of perceived caregiver strain, were collected. Patient-reported outcome measures from the CoULD registry, the Pediatric Outcomes Data Collection Instrument (PODCI), and Patient-Reported Outcomes Measurement Information System (PROMIS) were also analyzed for correlation with IOFS.

RESULTS

Two hundred ninety-nine caregivers participated. Factors with significantly stronger impact on family included public insurance; bilateral upper extremity involvement; household income of $20,000-40,000; additional musculoskeletal diagnosis; and a single adult caregiver household. There was a significantly increased subcategory of IOFS-Finance score for distant travel to see the surgeon. Additionally, all categories of the PODCI (upper extremity, mobility, sports, pain, happiness, and global) demonstrated a negative correlation with IOFS. PROMIS upper extremity and peer relations also demonstrated an inverse relationship with IOFS, whereas PROMIS pain interference had a positive correlation with IOFS. The overall IOFS for children with CoULDs was greater than previously reported for children with brachial plexus birth injury, and less than cerebral palsy and congenital heart disease.

CONCLUSIONS

Caregivers of children with congenital upper extremity differences report a significant impact on family life. Socioeconomic factors, such as economically disadvantaged or single-caregiver households, and clinical factors, such as bilateral upper extremity involvement, correlate with greater family impact. These findings represent opportunities to identify at-risk families and underscore the importance of caring for the whole family through a multidisciplinary approach.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Syndromic Involvement of Patients Presenting With Congenital Upper Limb Anomalies: An Analysis of 4,317 Cases

PURPOSE

This study investigated the patterns of syndromic involvement for patients with congenital upper limb anomalies (CULAs). We hypothesize that patients with CULAs will present with predictable syndromic patterns.

METHODS

This retrospective study queried the multicenter Congenital Upper Limb Differences (CoULD) Registry. Of the 4,317 patients enrolled, 578 (13%) reported one or more syndromes. Syndromes were confirmed to be recognized by the Online Mendelian Inheritance in Man. Demographics were reviewed and compared with the full CoULD registry group. Syndromes reported by five or more patients were examined to determine the type of CULA according to Oberg/Manske/Tonkin classifications.

RESULTS

Of the 578 children with one or more reported syndromes, 517 had Online Mendelian Inheritance in Man recognized syndromes (cohort A), In cohort A, 58 syndromes were each represented by a single patient within the registry. Forty-eight syndromes in cohort A were reported by two or more patients, which accounted for 461 of the total patients with reported syndromes. However, VACTERL and Poland syndromes were the most commonly reported syndromes. Patients with CULAs and syndromes frequently exhibited bilateral involvement (61%), compared with the entire CoULD group (47%) and other orthopedic (50%) and medical conditions (61%) compared with the entire CoULD group (24% and 27%, respectively). Additionally, they exhibited a lower frequency of family history of a congenital orthopedic condition (21%) or a family member with the same CULA (9%) compared with the entire CoULD group (26% and 14%, respectively).

CONCLUSIONS

Associated syndromes were recorded in 578 patients (13%) in the CoULD registry as follows: 58 syndromes represented by a single patient, 48 by 2 or more patients, and 23 syndromes by 5 or more patients. Rare syndromes that are only represented by a single patient are more likely to be unknown by a pediatric hand surgeon, and consultation with a geneticist is advised.

TYPE OF STUDY/LEVEL OF EVIDENCE

Differential Diagnosis/Symptom Prevalence Study IV.

Functional Outcomes and Health-Related Quality of Life of Adults With Congenital Below-Elbow Amputation in North America

PURPOSE

Congenital below-elbow amputation (BEA) is a common upper-extremity anomaly and generally encompasses 2 diagnoses, symbrachydactyly and transverse deficiency. Little is known about the physical, mental, and social well-being of adults with congenital BEA. A deeper understanding of longitudinal outcomes within this population may help guide family conversations and counseling for patients with congenital BEA.

METHODS

The Shriners Hospitals for Children Health Outcomes Network was queried to identify all patients currently >18 years of age who had been seen as a child between 1975 and 2019 for congenital BEA at 1 of 20 Shriners Hospitals across North America. A unique health survey examining physical functioning, mental health, social outcomes, and health-related quality of life was constructed and sent by mail or in electronic form to eligible patients.

RESULTS

A total of 64 questionnaires were completed. Patients ranged between 18 and 34 years of age, and 70% were female. Nearly two-thirds of patients (64%) reported that a prosthesis was not required and only 14% reported daily prosthetic use. Although respondents reported below-average Patient-Reported Outcomes Measurement Information System (PROMIS) upper-extremity scores, there were no differences in Short-Form 12 or Quick Disabilities of the Arm, Shoulder, and Hand scores relative to the US general population. Study participants had lower PROMIS Pain Intensity and higher PROMIS satisfaction with social roles and activities scores than the US general population, translating to clinically meaningful differences.

CONCLUSIONS

Although adults with congenital BEA report lower upper-extremity functional scores than the general population, they report no clear differences from normative values in self-efficacy, psychosocial well-being, health-related quality of life, or global life satisfaction.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

The Oberg, Manske, and Tonkin Classification of Congenital Upper Limb Anomalies: A Consensus Decision-Making Study for Difficult or Unclassifiable Cases

PURPOSE

An ideal classification system promotes communication and guides treatment for congenital upper limb differences (CULDs). The Oberg, Manske, and Tonkin (OMT) classification utilizes phenotypic presentation and knowledge of developmental biology for the classification of CULDs. In this consensus decision-making study, we hypothesized that CULDs that are difficult to classify would be identically classified by a group of experienced pediatric hand surgeons.

METHODS

An international consortium of 14 pediatric hand surgeons in 3 countries contributed a group of 72 difficult-to-classify CULD cases. These were identified from the clinical practices of the surgeons and from associated registries. Through a Delphi-type process, repeated efforts were made to obtain consensus for the correct OMT classification of each case utilizing clinical images and radiographs.

RESULTS

The first round of discussion yielded a universal consensus for 57 cases. The remaining 15 cases continued to be put through additional rounds of the Delphi-type process. The repeat classification and discussion resulted in a final yield of 93% complete consensus in classification by the OMT. The primary challenge in diagnosis was differentiating cleft hand from ulnar longitudinal deficiency, identified as group A. Five cases were in this group, yet 2 remained without a clear consensus. Another controversial group, group B, was termed "brachy-polydactyly" and consisted of 3 cases where diagnoses varied between sympolydactyly, symbrachydactyly, or complex syndactyly.

CONCLUSIONS

The Delphi-type process was feasible and effective and allowed a 93% consensus in the diagnosis of difficult-to-classify cases by the OMT Classification. There remain limitations and controversies with the OMT system, especially when classifying hands with less than 5 skeletal digits, syndactyly, and those with diagnostic overlap between ulnar longitudinal deficiency and cleft hand and those considered "brachypolydactyly." An improved understanding of the underlying etiology may be needed to determine the final diagnosis in difficult-to-classify conditions.

CLINICAL RELEVANCE

A consensus-seeking approach is effective and feasible in addressing difficult-to-classify CULDs.

An Analysis of Associated Conditions and the Relationship Between the Severity of Hand Manifestations With That of the Forearm in Ulnar Longitudinal Deficiency

PURPOSE

A deeper investigation of medical and musculoskeletal conditions in patients with ulnar longitudinal deficiency (ULD) is needed. The association between the severity of the manifestations of ULD in the hands and forearms has not been firmly established. The purpose of this study was to describe the medical and musculoskeletal conditions associated with ULD and examine the relationship between hand and forearm anomalies.

METHODS

The Congenital Upper Limb Differences registry was queried for all patients with a diagnosis of ULD, as defined by the Oberg-Manske-Tonkin classification system, between 2014 and 2020. The patients' demographic information, medical and musculoskeletal comorbidities, radiographs, and clinical images were reviewed. The participants were classified using the Bayne, Cole and Manske, and Ogino classification systems.

RESULTS

Of 2,821 patients from the Congenital Upper Limb Differences registry, 75 patients (2.7%) with ULD (14 bilateral), with 89 affected extremities, were included. Hand anomalies were present in 93% of the patients. Approximately 19% of the patients had an associated medical comorbidity, and 20% of the patients had an associated musculoskeletal condition. Cardiac anomalies were present in 8.0% of the patients, and 12% of the patients had a lower extremity abnormality. Radial head dislocation was observed in 13 of 18 patients with Bayne type II or III ULD compared with 8 of 43 patients with other types of unilateral ULD. There was a significant positive association among the Bayne and Ogino, Bayne and Cole/Manske, and Ogino and Cole/Manske classification systems in patients with unilateral ULD.

CONCLUSIONS

Associated medical and musculoskeletal conditions are common in patients with ULD, of which cardiac and lower extremity abnormalities are most frequently observed. There is a significant positive association between the severity of forearm anomalies and that of hand anomalies in patients with unilateral ULD. All patients with ULD should undergo a thorough cardiac evaluation by their pediatrician or a pediatric cardiologist.

TYPE OF STUDY/LEVEL OF EVIDENCE

Symptom prevalence study III.

Clinical evidence of the association between radial longitudinal deficiency and radial polydactyly: a case series

Radial longitudinal deficiency (RLD) is commonly associated with thumb hypoplasia. The association between RLD and radial polydactyly (RP) is uncommon, but case reports or case series have been reported. We report our experience of managing patients with this association. A total of 97 patients with RLD were seen in our department, of which six were children with concomitant RLD and RP. Four children had both RLD and RP in the same limb; of them, three also had RLD in the contralateral limb. The mean age at presentation was 11.6 months. Awareness of this association alerts the clinician to look for RLD in the presence of RP and vice versa. This case series supports recent experimental and clinical evidence that RP and RLD may be part of the same developmental spectrum. Further studies may guide its inclusion as a possible new category in the Oberg-Manske-Tonkin (OMT) classification of congenital upper-limb anomalies.Level of evidence: IV.

Correction of symbrachydactyly: a systematic review of surgical options

Symbrachydactyly is a rare congenital malformation of the hand characterized by short or even absent fingers with or without syndactyly, mostly unilaterally present. The hand condition can vary from a small hand to only nubbins on the distal forearm. This study aims to systematically review the surgical management options for symbrachydactyly and compare functional and aesthetic outcomes.The review was performed according to the PRISMA guidelines. Literature was systematically assessed searching the Cochrane Library, PubMed, Embase, and PROSPERO databases up to January 1, 2023. Studies were identified using synonyms for 'symbrachydactyly' and 'treatment'. Inclusion criteria were the report of outcomes after surgical treatment of symbrachydactyly in humans. Studies were excluded if they were written in another language than English, German, or French. Case reports, letters to the editor, studies on animals, cadaveric, in vitro studies, biomechanical reports, surgical technique description, and papers discussing traumatic or oncologic cases were excluded.Twenty-four studies published were included with 539 patients (1037 digit corrections). Only one study included and compared two surgical techniques. The quality of the included studies was assessed using the Modified Coleman Methodology Score and ranged from 25 to 47. The range of motion was the main reported outcome and demonstrated modest results in all surgical techniques. The report on aesthetics of the hand was limited in non-vascularized transfers to 2/8 studies and in vascularized transfers to 5/8 studies, both reporting satisfactory results. On average, there was a foot donor site complication rate of 22% in non-vascularized transfers, compared to 2% in vascularized transfers. The hand-related complication rate of 54% was much higher in the vascularized group than in the non-vascularized transfer with 16%.No uniform strategy to surgically improve symbrachydactyly exists. All discussed techniques show limited functional improvement with considerable complication rates, with the vascularized transfer showing relative high hand-related complications and the non-vascularized transfer showing relative high foot-related complications.There were no high-quality studies, and due to a lack of comparing studies, the data could only be analysed qualitatively. Systematic assessment of studies showed insufficient evidence to determine superiority of any procedure to treat symbrachydactyly due to inadequate study designs and comparative studies. This systematic review was registered at the National Institute for Health Research PROSPERO International Prospective Register of Systematic Reviews number: CRD42020153590 and received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.Level of evidenceI.Systematic review registrationPROSPERO CRD42020153590.

Surgical Reconstruction for the Triphalangeal Thumb

The triphalangeal thumb poses a complex reconstructive challenge to the congenital hand surgeon due to its rarity and variable anatomy. We discuss the available evidence, reporting clinical characteristics and outcomes of surgical reconstructive procedures of triphalangeal thumb alongside a representative case. The congenital hand surgeon must approach each patient with triphalangeal thumb individually to optimize the use of available tissues to maximize functional and aesthetic outcomes.

Congenital Upper-Limb Differences: A 6-Year Literature Review

➤ The Oberg-Manske-Tonkin (OMT) classification of congenital hand and upper-limb anomalies continues to be refined as our understanding of the genetic and embryonic etiology of limb anomalies improves.➤ We have conducted an evaluation of graft and graftless techniques for syndactyly reconstruction; strengths and drawbacks exist for each technique.➤ Treatment for radial longitudinal deficiency remains controversial; however, radialization has shown promise in early follow-up for severe deformities.➤ Recent emphasis on psychosocial aspects of care has demonstrated that children with congenital upper-limb differences demonstrate good peer relationships and marked adaptability.

Epidemiology of Congenital Upper-Limb Anomalies in Southern Taiwan Based on the Updated Oberg, Manske, and Tonkin Classification: A Series of 1,335 Anomalies in 1,188 Patients

PURPOSE

This study aimed to investigate the relative frequency of congenital upper-limb anomalies (CULAs) in southern Taiwan using the 2020-updated the Oberg, Manske, and Tonkin (OMT) classification system and evaluate the practicality of the new classification system.

METHODS

We retrospectively reviewed patients with CULAs from 1987 to 2021 at a referral center in southern Taiwan. All patients were analyzed based on medical records, photographs, and radiographs, and the anomalies were classified according to the 2020 OMT classification system.

RESULTS

A total of 1,188 patients with 1,335 CULAs were retrospectively reviewed. The results demonstrated that the most common type of CULA was malformations (1,092 cases), followed by dysplasias (144 cases), syndromes (51 cases), and deformations (48 cases). Among the malformations, radial polydactyly was the most common anomaly (732 cases), followed by simple syndactyly (66 cases). Among the dysplasias, camptodactyly was the most common anomaly (52 cases), followed by thumb-in-palm deformity (45 cases) and vascular tumors (17 cases). In the deformations, constriction ring sequence accounted for all cases. Poland syndrome (21 cases) occurred most often in the category of syndromes.

CONCLUSIONS

The results of this study show that radial polydactyly (732 cases, 55%) is the most common CULA in southern Taiwan, followed by simple syndactyly (66 cases, 5%) and then camptodactyly (52 cases, 4%).

CLINICAL RELEVANCE

The OMT classification system is reasonably practical for precise classification of CULAs and enables easy comparison of studies over different time periods. However, continually updating the OMT classification system is required to better categorize the highly variable presentations of CULAs.

Integrative Role of the SALL4 Gene: From Thalidomide Embryopathy to Genetic Defects of the Upper Limb, Internal Organs, Cerebral Midline, and Pituitary

BACKGROUND

The thalidomide disaster resulted in tremendous congenital malformations in more than 10,000 children in the late 1950s and early 1960s.

SUMMARY

Although numerous putative mechanisms were proposed to explain thalidomide teratogenicity, it was confirmed only recently that thalidomide, rather its derivative 5-hydroxythalidomide (5HT) in a complex with the cereblon protein, interferes with early embryonic transcriptional regulation. 5HT induces selective degradation of SALL4, a principal transcriptional factor of early embryogenesis. Genetic syndromes caused by pathogenic variants of the SALL4 gene phenocopy thalidomide embryopathy with congenital malformations ranging from phocomelia, reduced radial ray, to defects of the heart, kidneys, ear, eye, and possibly cerebral midline and pituitary. SALL4 interacts with TBX5 and a handful of other transcriptional regulators and downregulates the Sonic hedgehog signaling pathway. Cranial midline defects, microcephaly, and short stature due to growth hormone deficiency have been occasionally reported in children carrying SALL4 pathogenic variants associated with generalized stunting of growth rather than just the loss of height attributable to the shortening of leg bones in many children with thalidomide embryopathy.

KEY MESSAGES

Thus, SALL4 joins the candidate gene list for monogenic syndromic pituitary insufficiency. In this review, we summarize the journey from the thalidomide disaster through the functions of the SALL4 gene to its link to the hormonal regulation of growth.

Camptodactyly: From Embryological Basis to Surgical Treatment

Camptodactyly is a relatively rare hand deformity presenting as the proximal interphalangeal joint's nontraumatic and progressive flexion contracture. Most cases are limited to the fifth finger. The severity and type of camptodactyly should be considered to optimize treatment. Since many structures at the finger base can be involved in the pathogenesis of the deformity, surgical treatment for this particular type of deformity is challenging. This paper aims to bring insight into camptodactyly's pathogenesis and treatment options. We discuss the indication and pitfalls of surgical treatment options for particular camptodactyly types and present a case of a fourteen-year-old boy who was admitted to our department with proximal interphalangeal joint flexion contracture of the left fifth digit.

Factors affecting hand cosmesis and the aesthetic impact of surgery on congenital hand differences in Finland

We assessed the appearance and cosmetic impact of surgery in congenitally different hands in Finland. A questionnaire was sent to 1165 respondents (786 female) with a mean age of 33 years (range 3-84). Participants were shown nine image pairs and seven pairs of pre- and postoperative images twice in a random order and asked to choose the more cosmetically pleasing one. We found that the appearance and number of fingers had an important aesthetic role, with higher number and more normal appearing digits consistently scoring higher than its counterpart (range 59-99%). Postoperative appearances were perceived as better than preoperative ones in syndactyly (98%), thumb duplication (92%), cleft hand (93%) and radial dysplasia (99%). Toe transfer and pollicization had little impact on cosmesis. This study demonstrated that surgery could improve cosmesis in congenitally different hands and overall, most respondents prefer an appearance that is as close as possible to normality. Level of evidence: IV.

Congenital Palmar Duplication of the Index Finger: Ventral Polydactyly With Ventral Dimelia

This report describes the case of a 10-month-old boy who presented with a duplicated index finger enveloped by palmar skin on the palmar side of the first web of the left hand. He was healthy without any other abnormalities except the hand anomaly. Surgical resection of the extra finger was performed with triangular flap at 15 months of age. The resected finger was composed of only palmar components: skin without nail or hair; flexor tendons; and digital nerves branching from the median nerve. Histological examination of the specimen demonstrated similar structures on both palmar and dorsal sides, that is, ridged, hairless, and glabrous skin with a high number of epithelial layers and thick corneous stratum and similar shaped tendons inserted into the symmetrical phalanx. This appears to be the first report in literature of an ectopic palmar index finger, a ventral polydactyly with ventral dimelia.

Cutis Calcinosis of the Hand in 2 Patients With Symbrachydactyly

Cutis calcinosis of the hand in the setting of symbrachydactyly is presented in 2 unique patients. Both lesions were treated based on the standard of care protocols with resection of the calcified mass and hand reconstruction, as appropriate. The patients healed uneventfully without recurrence of the calcification at a the 1-year follow-up. The association between symbrachydactyly and calcinosis cutis is discussed along with a hypothesis on the pathophysiologic mechanism that could potentially explain this unusual occurrence and why it might be more common than previously identified.

Inter- and intra-rater reliability of the Oberg-Manske-Tonkin classification of congenital upper limb anomalies

On two occasions, five surgeons classified a cohort of 150 consecutive patients with congenital upper limb anomalies according to the Oberg-Manske-Tonkin classification (2020 update). We estimated reliability for the main anomaly code by means of Cohen's kappa (Κ) for ten rater pairs for five common and easily distinguishable anomalies (Group 1), and for all the other anomalies (Group 2). Inter-rater reliability for all patients (n = 150) was substantial, almost perfect for Group 1 (n = 64), but only moderate for Group 2 (n = 86). Intra-rater reliability was higher for all groups. We suggest simplifications to the Oberg-Manske-Tonkin classification and highlight specific requirements for instructions to increase its reliability.Level of evidence: I.

The Impact of Isolated Versus Multiple Osteochondromas: Analysis of the CoULD Registry

PURPOSE

The burden of upper extremity (UE) osteochondromas on function and self-perception among pediatric patients is unclear. The purpose of our study was to study the impact of osteochondromas in comparison to population norms and to evaluate solitary versus multiple osteochondromas on subjective UE function as measured by patient rated outcomes.

METHODS

We utilized the CoULD (Congenital Upper Limb Differences) Registry to review all pediatric patients presenting with osteochondromas between January 2014 and February 2021. Demographic information was collected and patients were classified as having either single or multiple osteochondromas. Patient-Reported Outcome Measurement Information System (PROMIS) and Pediatric Outcomes Data Collection Instrument (PODCI) tools were utilized for assessment. Scores for PODCI subscales of UE function, Pain/comfort, and Happiness and PROMIS domains of UE Function, Pain, Depression, Anxiety, and Peer Relations were reviewed. Differences between groups were analyzed using the Student t test.

RESULTS

Ninety-nine patients met inclusion criteria for the study with an average age of presentation of 9.3 years and 61 patients (62%) were male. Overall, patients demonstrated worse UE Function as well as greater Anxiety and Depression in comparison to the population normals on PROMIS assessment. Patients also demonstrated worse patient and parent reported PODCI UE, Sports and Physical Functioning, Pain/Comfort and Global Functioning scores compared with population norms but demonstrated better than average happiness scores. Patients with multiple osteochondromas demonstrated greater PROMIS pain interference and more disability in PODCI Sports and Physical Functioning, Pain/Comfort and Global Functioning compared with those with solitary osteochondromas.

CONCLUSION

Patients with UE osteochondromas have worse overall function in comparison to population norms, exceeding established minimally clinically important difference values. In addition, patients with multiple osteochondromas reported more pain and poorer physical function than those with solitary osteochondromas. Physicians should be alert to the physical and psychosocial burden of this disease.

LEVEL OF EVIDENCE

Level II-prognostic.

Congenital Disorders of the Pediatric Thumb

»

Surgical timing for pediatric trigger thumb treatment is controversial for numerous reasons including the potential for spontaneous resolution, the possibility of bilateral involvement, and anesthesia concerns regarding the developing brain. Hence, a reasonable approach is to delay the surgical procedure until the patient is ≥3 years of age.

»

Preaxial polydactyly is usually unilateral and sporadic, with the most common reconstruction method consisting of excision of the diminutive thumb with preservation and soft-tissue reconstruction of the dominant thumb. The surgical procedure is typically performed around the patient age of 1 year to decrease the risks of anesthesia but allow reconstruction prior to the development of a tip-to-tip pinch.

»

Triphalangeal thumb and thumb hypoplasia are often found in the setting of systemic anomalies such as Holt-Oram syndrome, thrombocytopenia absent radius syndrome, Fanconi anemia, VACTERL (vertebral anomalies, anal atresia, cardiac anomalies, tracheoesophageal fistula, renal defects, and limb anomalies), and/or Blackfan-Diamond anemia. As such, patients should receive adequate workup for these entities. A surgical procedure should be performed only once patients have been medically cleared.

»

The status of the carpometacarpal joint in thumb hypoplasia determines whether reconstruction with first web space deepening, collateral ligament stabilization, and opponensplasty compared with index pollicization is performed.

Congenital hand differences: Prevalence among school going children in Mangalore city

Introduction

Congenital upper extremity anomalies are present in 1 in every 626 live births. They are mostly isolated phenomena but can also be associated with other congenital deformities and may be the only external feature of a syndromic entity. A study on it in India, especially the southern part, is limited. As the quality of life gets compromised, there is a need to identify and diagnose the anomalies at the earliest. Current study is aimed to identify congenital hand deformities among the school-going population in the coastal city of Mangalore.A cross sectional study was done in the schools in Mangalore city. By simple random sampling, 35 out of 70 schools were selected, and 10,000 children in age group of 5-15years were included by non-probability sampling after taking their consent from school authorities and parents. Data was analyzed by FISHER's exact test.

Result

41 cases of congenital hand anomalies were identified with 23 boys and 18 girls. Twelve children had bilateral involvement. 28 cases where of polydactyly followed by four cases of acrosyndactyly with constriction band, three cases each of syndactyly and camptodactyly,one case of lobster hand and one case each of transverse deficiency of hand and forearm. Associated lower limb anomalies were seen in 9 cases. Familial associations were seen in 6 cases, and 1 polydactyly child had a downs syndrome association. All cases[4cases] of acrosyndactyly with constriction band syndrome were operated at childhood, and most other deformities were unoperated. Polydactyly[duplication] tops the list and needs further studies to look into genetic, environmental, and regional variations.

Conclusion

The prevalence of congenital hand difference in Mangalore is 41 per 10000 school-going children examined. . A future national registry in India should be the way forward to assess the true prevalence and risk factors.

The Effect of Adoption on Functioning and Psychosocial Well-Being in Patients With Congenital Upper-Extremity Differences

PURPOSE

Adoption status has been investigated in numerous populations, identifying negative and positive effects on patient outcomes. This study compared parent-reported outcomes in adopted and nonadopted individuals with congenital upper-extremity (UE) anomalies to determine whether there was a measurable difference in parent perceptions of psychosocial health and functioning.

METHODS

The Congenital Upper Limb Differences registry identified adopted individuals from a large cohort of patients. Each adopted patient was matched to 2 nonadopted patients by sex, age, and diagnosis of UE difference using the Oberg-Manske-Tonkin classification. Parent-reported scores on functional and psychosocial subjective outcomes were compared between the 2 cohorts using the Pediatric Outcome Data Collection Instrument.

RESULTS

Ninety-one adopted pediatric patients with congenital UE differences were identified. Sixty had complete matches for comparison, and the remaining 31 patients were not able to be matched and were excluded from the analysis. Pediatric Outcome Data Collection Instrument scores for the UE function domain were worse in the adopted cohort as judged by minimally clinically important difference. In contrast, scores for Pediatric Outcome Data Collection Instrument domains of transfer and mobility, sports and physical function, pain and comfort, and happiness did not exceed the minimally clinically important difference, although the adopted cohort scores were all relatively lower than the nonadopted cohort scores.

CONCLUSIONS

In pediatric patients with UE differences, adoption status is seen to affect only the parent-reported domain of UE function. While differences by specific congenital diagnosis call for additional investigation, overall, these findings should be reassuring to families planning to adopt children with UE differences, and they should be supported in their expectations of UE functioning.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic III.

Congenital Upper Limb Differences Registry (CoULD): Registry Inclusion Effect

PURPOSE

To advance the understanding of the epidemiology and treatment outcomes of congenital upper limb differences, a multicenter registry for Congenital Upper Limb Differences (CoULD) was established. After 4 years of recruitment, we sought to examine whether the relative frequency of congenital conditions compares with prior cross-sectional research and how the data have matured over time by (1) comparing our registry population with previous studies in similar populations and (2) evaluating the change over time of relative frequencies of selected conditions within the CoULD registry cohort, specifically to investigate for registry inclusion effects.

METHODS

Data from the 2 founding centers in the CoULD registry were analyzed over a 4-year period. We compared patients included in the CoULD registry against 2 prior studies by matching each condition according to the Oberg-Manske-Tonkin classification system. The relative frequency of 4 representative conditions was calculated to evaluate change over time and to determine when the inception cohort effect diminished.

RESULTS

The CoULD cohort of 1,381 patients was found to have notable differences compared with a 1-year cross-sectional cohort from the U.S. Midwest and a Swedish birth registry. Each of these registries had differences from the CoULD population in prevalence for approximately 33% of the diagnosis categories. The CoULD registry identified and included more pathologies of late presentation and those that do not commonly require surgical care. Changes in relative frequencies of incident and prevalent conditions, the registry inclusion effect, occurred early and stabilized by the third year.

CONCLUSIONS

The CoULD registry captures a different relative frequency of conditions than prior studies in similar populations. The findings highlight the CoULD registry may be a more accurate representation of clinical practice in tertiary referral centers; however, it is important to note that there was a registry inclusion effect identified.

CLINICAL RELEVANCE

Inclusion criteria are an important consideration with any longitudinal data collection method and data should display stability prior to registry reporting.

The Story of the Hand

This review describes the Story of the Human Hand. It traces the functional needs that led to evolution of the human hand as well as its embryological development. The various in utero stages of formation of the human hand are covered along with a description of the various molecular and genetic factors that control this process.

The Classification of VACTERL Association into 3 Groups According to the Limb Defect

The VACTERL association (VA) is defined as the nonrandom co-occurrence of 6 anomalies: vertebral anomalies (V), Anal atresia (A), Cardiac defects (C), Tracheo-esophageal fistula (TE), Renal defects (R), and Limb anomalies (L). The current communication presents an argument that patients with VA should be classified into three district groups based on their limb defects: VACTERL1: patients with normal limbs; VACTERL2: patients with limb anomalies other than radial ray defects of the upper limbs; and VACTERL3: patients with radial ray defects of the upper limbs. The author will demonstrate that the rationale behind the L1-3 classification in patients in VA is based on the embryogenesis of the 6 affected anatomical areas in VA. The pathogenesis of VACTERL1 is secondary to perturbations of Sonic Hedgehog (SHH) interactions. SHH signaling is known to have a major role in the normal development of the vertebrae, ano-rectal area, heart, tracheo-esophageal area, and kidney. However, SHH is not involved in the development of the radial ray; hence, patients present with no limb defects. The pathogenesis of VACTERL2 is variable depending on the type of gene mutation. The pathogenesis of VACTERL3 is related to errors in a group of proteins (namely, the proteins of the TBX5-SALL4-SALL1 loop and the FGF8-FGF10 loop/ pathway). These proteins are essential for the normal development of the radial ray and they interact in the development of the other anatomical areas of VA including the heart and kidney. Hence, VACTERL3 patients present with radial ray deficiency.

Social Deprivation and Congenital Upper Extremity Differences-An Assessment Using PROMIS

PURPOSE

Social deprivation, a measure of socioeconomic status, has been shown to negatively affect perceptions of orthopedic conditions and outcomes of treatment. The objective of this study was to assess whether social deprivation correlates with subjective assessment of function in pediatric patients with congenital hand differences.

METHODS

Patients enrolled in the Congenital Upper Limb Differences (CoULD) registry were assessed using the Patient-Reported Outcomes Measurement Information System (PROMIS). The PROMIS scores for Pain Interference, Peer Relations, Anxiety, Depression, and Upper Extremity (UE) function were obtained for all patients 5 years and older at initial presentation. Social deprivation was determined by the Area Deprivation Index (ADI); the index ranges from 0 to 100 with higher scores being the most deprived. The PROMIS scores were correlated with the ADI for all patients.

RESULTS

Three hundred seventy-five pediatric patients with congenital UE differences were evaluated. Average age was 11 years, 56% were female, and 55% had bilateral involvement. Overall, PROMIS scores were within 1 SD of normal for Peer Relations, Pain, Depression, and Anxiety. However, child-reported scores for UE function (39) were more than 1 SD below the national average (50). The mean ADI for the cohort was lower than the national average, indicative of less deprivation, with 14% of patients in the most deprived national quartile. Children in the highest ADI quartile reported PROMIS scores that reflected higher Pain Interference (41 vs 45), lower Peer Relations (55 vs 50), higher Anxiety (44 vs 49), and higher Depression (43 vs 47) than children in the lowest ADI quartile.

CONCLUSIONS

The PROMIS scores were normal for psychosocial measures in children with congenital hand differences when evaluated as an entire cohort. However, child self-reported PROMIS scores for Pain Interference, Peer Relations, Anxiety, and Depression were worse in more socially deprived areas, suggesting more psychosocial challenges in these children.

CLINICAL RELEVANCE

Pediatric patients with congenital upper extremity differences in areas of higher social deprivation report lower psychosocial well-being. The care of these individuals must be considered within the context of their environment because they may be more at risk for negative outcomes secondary to environmental and societal stressors.

Prevalence and risk factors of radial ray deficiencies: A population-based case-control study

Radial ray deficiency is the most common congenital deficiency of the upper limb. The aim of our study was to investigate maternal risk factors for radial ray deficiencies. We conducted a nationwide population-based case-control study using national registers. All cases with a radial ray deficiency born between 1996 and 2008 were included in the study and compared with five controls without limb deficiency. In total, 115 (10 isolated, 18 with multiple congenital anomalies, and 87 syndromic) cases with radial ray deficiencies were identified and compared with 575 matched controls. The total prevalence in Finland was 1.22 per 10,000 births. No significant risk factors were observed for nonsyndromic cases. In the syndromic group, advanced maternal age (≥35 years) increased the risk of radial aplasia (aOR 2.45, 95% CI 1.37-4.36), and a similar association was observed with multiple pregnancy (aOR 2.97, 1.16-7.62) and male sex (aOR 1.96, 1.18-3.25). Valproic acid was also a risk factor (p = .002). In conclusion, novel associations in the syndromic group of advanced maternal age and multiple pregnancy and increased risk of radial ray deficiencies were observed. Also, early reports on increased risk of RRD associated with valproate and male sex were supported by our results.

Clinical and epidemiological features of heart-hand syndrome, an updated analysis in China

BACKGROUND

The purpose of this study was to prospectively recruit patients treated with limb malformation and to explore the prevalence and the clinical and epidemiological features of Heart-Hand Syndrome (HHS) in China.

METHODS

The consecutive patients treated for congenital upper limb malformation in Beijing Ji Shui Tan Hospital from October 1st, 2016 to October 1st, 2019 were prospectively recruited. We reviewed the patients' medical records and identified patients with abnormal electrocardiogram (ECG) and/or abnormal ultrasonic cardiogram as well as their basic demographic and clinical characteristics.

RESULTS

A total 1653 (1053 male and 600 female) patients with congenital upper extremity malformations were prospectively recruited. Among them, 200 (12.1%) had abnormal ultrasonic cardiogram (181patients, 10.9%) and/or abnormal ECG (19 patients, 1.1%). The commonest type of abnormal heart structure was atrial septal defect (69/181 38.1%), and the commonest abnormal ECG was wave patterns (7/19, 36.8%). HHS patients had a higher comorbidity rate (11%) than non-HHS patients (6.9%). Patients with HHS were classified into four groups by the types of congenital upper extremity malformations, among which the most common group was thumb type (121/200, 60.5%).

CONCLUSIONS

HHS occurred frequently among patients with congenital upper extremity malformation in China, particularly for those with multiple congenital malformations. The commonest type of hand malformations of HHS patients was thumb malformation.

Association of Radial Longitudinal Deficiency and Thumb Hypoplasia: An Update Using the CoULD Registry

BACKGROUND

Deficiency of the radial aspect of the forearm and hand is the most common congenital longitudinal deficiency of the upper limb. Radial longitudinal deficiency is associated with several named syndromes. The purpose of the present study was to explore patterns of radial longitudinal deficiency and thumb hypoplasia in syndromes and to examine the severity of these differences across various syndromes.

METHODS

Data were collected from the Congenital Upper Limb Differences (CoULD) registry. Congenital differences are classified in the registry with use of the Oberg-Manske-Tonkin (OMT) classification system. Diagnosis of a syndrome by a physician as noted in the CoULD registry was recorded. Thumb deficiency and radial deficiency were classified according to the modified versions of the Blauth criteria and the Bayne and Klug criteria, respectively.

RESULTS

We identified 259 patients with 383 affected limbs with radial deficiency. Eighty-three of these patients had a diagnosed syndrome. The severity of radial deficiency was correlated with the severity of thumb deficiency. The Kendall tau coefficient indicated significant correlation between radial severity and thumb severity (tau = 0.49 [95% confidence interval = 0.40 to 0.57]; p < 0.05). Subjects with a syndrome were twice as likely to have bilateral deficiency and 2.5 times more likely to have both radial and thumb deficiency compared with subjects without a syndrome. Subjects with VACTERL syndrome (vertebral defects, anal atresia, cardiac anomalies, tracheoesophageal fistula, renal anomalies, and limb defects) had patterns of thumb and radial deficiency similar to the general cohort, whereas subjects with Holt-Oram syndrome, TAR (thrombocytopenia absent radius) syndrome, and Fanconi anemia demonstrated varied presentations of thumb and radial deficiency.

CONCLUSIONS

The present study investigated the characteristics of patients with radial longitudinal deficiency and thumb hypoplasia. Our results support the findings of previous research correlating the severity of radial deficiency with the severity of thumb deficiency. Furthermore, we identified characteristic features of patients with radial longitudinal deficiency and associated syndromes.

What's New in Congenital Hand Surgery

BACKGROUND

Congenital conditions of the hand and upper extremity are a frequent source of consultation among pediatric orthopaedists and hand surgeons. Advances in the fields of molecular biology and genetics have helped to better understand some of these conditions and redefine previous classification systems. New outcome measurement tools have been used to assess surgical results and have brought into focus a different aspect of the patients' experience.

METHODS

We searched PubMed database for papers related to the treatment of congenital hand anomalies published from January 1, 2015 to October 31, 2018. The search was limited to English articles yielding 207 papers. Three pediatric hand surgeons selected the articles based upon the criteria that the topic was germane, the article fell under the subheadings within the manuscript, and the conclusions were meaningful.

RESULTS

A total of 40 papers were selected for review, based upon their quality and new findings. Research articles with significant findings were included for syndactyly, symbrachydactyly, cleft hand, polydactyly, radial longitudinal deficiency, congenital radio-ulnar synostosis, and macrodactyly.

CONCLUSIONS

Our knowledge of the embryology and pathophysiology of congenital upper extremity conditions continues to evolve. Functional assessments combined with patient and parent-reported outcomes have our understanding of the results following surgical procedures. Further research and standardization of our scientific data will provide better answers and higher quality of evidence.

LEVEL OF EVIDENCE

Level V-literature review and expert opinion.

The Oberg-Manske-Tonkin (OMT) Classification of Congenital Upper Extremities: Update for 2020

A new classification for congenital upper-extremity anomalies was first published in 2010. It has come to be known as the OMT classification highlighting the thought leaders behind it: Kerby Oberg, Paul Manske, and Michael Tonkin. Based on a dysmorphology framework, the OMT has been adopted by the International Federation of Society for Surgery of the Hand and surgeons who treat congenital upper-extremity anomalies. As predicted in the first publication, updates will be necessary based on an improved understanding of morphogenesis; the first update was in 2014 and this represents the second update to the original OMT classification. We carefully reviewed all aspects of the OMT classification, its current stratification, and updated literature on the developmental basis of limb anomalies. We also considered the clinical usefulness and challenges of the classification through discussions with stakeholders and those who care for patients with congenital upper-limb anomalies. These factors guided the current modifications of the OMT classification. In providing the updated classification, we provide the rationale for these changes. The updated OMT classification is by no means final. As our understanding of congenital anomalies progresses, we anticipate subsequent updates in the years to come.

Oberg-Manske-Tonkin Classification of Congenital Upper Extremity Anomalies: The First Report From Turkey

PURPOSE

Although the Oberg-Manske-Tonkin (OMT) classification has been recommended by the International Federation of Societies for Surgery of the Hand owing to some insufficiencies of the Swanson classification system, it has not achieved a universal adoption by hand surgeons. In this study, we hypothesize that the OMT classification can be used easily to classify congenital upper extremity anomalies. We also aim to make epidemiological analysis of congenital upper extremity anomalies with the OMT classification and to compare the applicability of the OMT and the Swanson classifications.

METHODS

We retrospectively analyzed 711 patients and 833 extremities operated on between 2012 and 2017. Photographs, plain x-rays, and brief medical histories of the patients were evaluated by 4 plastic surgeons. Two independent evaluations were made by each surgeon in 1-month interval using these classification systems.

RESULTS

Total number of upper extremity anomalies recorded was 1050. Of the 711 patients operated on, 122 had bilateral anomalies. The anomalies were identified in 833 extremities because many extremities had more than a single diagnosis. We were able to classify all of the anomalies within the OMT classification. The OMT classification gives better reliability results compared with the Swanson classification according to intrarater and interrater reliabilities.

CONCLUSIONS

Compared with the Swanson classification system based on phenotypic evaluation of the extremity, the OMT classification system is easier to apply and the association of the anomaly with the embryologic origin during evaluation is possible. We believe that multiple studies from different centers will boost the international acceptance of the OMT classification.

Radial Longitudinal Deficiency: Severity Differences Between U.S. and Japanese Cohorts

PURPOSE

Radial longitudinal deficiency (RLD) presents on a spectrum of severity and associated diagnoses. The literature is limited in describing patient presentation without comparative data between countries. In a study comparing 2 cohorts of patients, 1 in the United States and 1 in Japan, we hypothesized that there would be a similar presentation of forearm deficiency severity, thumb hypoplasia severity, and associated syndromes between the 2 cohorts.

METHODS

Patients with RLD were identified via a comprehensive chart review at 2 pediatric hospital cohorts, 1 in the United States and 1 in Japan, capturing patients presenting over 15 years. We assessed RLD and thumb hypoplasia severity via a modified Bayne and Klug and modified Blauth classifications. The relationship between these 2 diagnoses and the presence of common medical conditions were evaluated and correlated.

RESULTS

A total of 194 Japanese patients with 290 involved extremities were compared with 107 U.S. patients with 174 involved extremities. The U.S. cohort had a significantly more severe RLD, and a higher rate of bilaterality (63% vs 50%, respectively). A total of 131 Japanese patients (68%) and 41 U.S. patients (38%) had associated medical syndromes/associations, most frequently vertebral abnormalities, anal atresia, cardiac abnormalities, tracheoesophageal fistula and/or esophageal atresia, renal agenesis and dysplasia, and limb defects (VACTERL; 46 Japanese, 14 U.S.), Holt-Oram (44 Japanese, 5 U.S.), and thrombocytopenia absent radius syndrome (0 Japanese, 12 U.S.). Correlation analysis showed that increased RLD severity was associated with increased thumb hypoplasia severity in both groups, with 95% of modified Bayne and Klug III, IV, or V patients having severely affected thumbs (type IIIb, IV, or V).

CONCLUSIONS

The U.S. patients had a more severe RLD and a higher rate of bilaterality. Japanese patients had a higher incidence of associated syndromes and radial polydactyly. Both cohorts showed that increased forearm severity was associated with more severe thumb hypoplasia.

TYPE OF STUDY/LEVEL OF EVIDENCE

Differential diagnosis/symptom prevalence study III.

Thumb Hypoplasia Occurring in Patients With Preaxial Polydactyly

PURPOSE

Thumb polydactyly and thumb hypoplasia are generally regarded as separate clinical entities. However, several case reports indicate that hypoplasia of both the thumb and the radius can occur in patients with thumb polydactyly and improved understanding of the genetics of the developing upper limb may give an embryologic explanation for this occurrence. Our hypothesis was that patients with preaxial polydactyly can have ipsilateral thumb hypoplasia that may not be recognized until after surgical reconstruction of the extra digit.

METHODS

We searched our surgical database for all procedures performed on patients with a diagnosis of preaxial polydactyly between 2002 and 2014. We reviewed the medical record for demographic data, surgical procedures, and follow-up information. In addition, all available radiographs were reviewed. Through this, we identified patients with a diagnosis of ipsilateral thumb hypoplasia, including when in the course of treatment the diagnosis was made, and any related subsequent procedures.

RESULTS

We reviewed 132 patients who underwent reconstruction of thumb polydactyly, 10 of whom were identified as having evidence of ipsilateral thumb hypoplasia, an incidence of 8.2%. The diagnosis of thumb hypoplasia was made before surgery in 3 of the 10 patients. One additional patient was noted to have a duplicate thumb on one side and a hypoplastic thumb on the contralateral side.

CONCLUSIONS

This study supports the hypothesis that children with preaxial polydactyly can have ipsilateral thumb hypoplasia that may not be noted before surgery. In this study group, 8% of patients with preaxial polydactyly had ipsilateral hypoplasia.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Dorsal Hexagon Local Flap Without Skin Graft for Web Reconstruction of Congenital Syndactyly

PURPOSE

The ideal web reconstruction for syndactyly requires both satisfactory function and aesthetic appearance. In this study, we report a dorsal hexagon local flap with adequate size and that leaves most of the scars in the interdigital space.

METHODS

Between June 2015 and June 2017, 16 patients (10 males and 6 females) with 22 syndactylies underwent surgical reconstruction using the dorsal hexagon local flap technique. All patients had simple syndactyly. The postoperative evaluation included the quality of scarring, the extent of flexion and extension deformity, web creep, lateral flexion deformity, and rotational deformity of the digit.

RESULTS

All flaps survived and there were no postoperative complications. All patients achieved satisfactory interdigital commissure depth. During 12 to 34 months of follow-up, no case of flexion contracture or web creep after reconstruction was noted.

CONCLUSIONS

The dorsal hexagon local flap is an alternative method for syndactyly reconstruction.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Convergent Validity of PODCI and PROMIS Domains in Congenital Upper Limb Anomalies

PURPOSE

This study evaluates the perceived functional and psychosocial impact of upper limb congenital anomalies prior to surgical intervention, utilizing the Pediatric Outcomes Data Collection Instrument (PODCI) and Patient-Reported Outcomes Measure Information System (PROMIS) domains. We hypothesized that scores will be in the normal range and that the 2 outcomes measures will have strong convergent validity.

METHODS

A multicenter prospectively collected database of congenital upper limb patients, the CoULD (Congenital Upper Limb Differences) study group, was utilized. Demographic information was collected, and anomalies were classified by the Oberg-Manske-Tonkin (OMT) classification. Scores for PODCI subscales of Upper Extremity (UE) function, Pain/comfort, and Happiness and PROMIS domain of UE function, Pain, Depression, Anxiety, and Peer relations were collected. Ceiling and floor effects and convergent validity for PODCI and PROMIS domains were calculated.

RESULTS

Three hundred fifty-nine patients, average age 10 years and 55% male, were included. Two hundred forty-one patients had a malformation of the entire limb and 231 had a hand plate malformation. Four patients had a deformation, 118 dysplasia, and 45 a syndrome. There was no difference between the PODCI and the PROMIS ceiling or floor effects for the UE domains. The ceiling effect for PROMIS Pain domain (46%) was similar to the floor effect of the PODCI Pain subscale and no difference was seen between the floor effect of PODCI Happiness and PROMIS Depression domains. Convergent validity was obtained for the UE and Pain domains, and also between PODCI Happiness and PROMIS Depression subscales.

CONCLUSIONS

The PROMIS domains for UE function, Pain, and Depression are comparable with PODCI scores in congenital upper extremity anomalies.

CLINICAL RELEVANCE

Given the large burden placed on patients with the lengthy PODCI questionnaire, consideration of replacing the PODCI with the more quickly obtained PROMIS scores may reduce patient burden and provide similar information in this population.

A multidisciplinary review of triphalangeal thumb

Despite being a rare congenital limb anomaly, triphalangeal thumb is a subject of research in various scientific fields, providing new insights in clinical research and evolutionary biology. The findings of triphalangeal thumb can be predictive for other congenital anomalies as part of an underlying syndrome. Furthermore, triphalangeal thumb is still being used as a model in molecular genetics to study gene regulation by long-range regulatory elements. We present a review that summarizes a number of scientifically relevant topics that involve the triphalangeal thumb phenotype. Future initiatives involving multidisciplinary teams collaborating in the field of triphalangeal thumb research can lead to a better understanding of the pathogenesis and molecular mechanisms of this condition as well as other congenital upper limb anomalies.

Distal Dorsal Dimelia: A Disturbance of Dorsal-Ventral Digit Development

PURPOSE

Congenital palmar nail (distal dorsal dimelia [dDD]) of the hand is a rare malformation most commonly affecting the little finger. The purpose of this report was to review the features and associations of this rare disorder and discuss the suspected underlying etiology in light of our current understanding of developmental biology.

METHODS

In this retrospective cohort study from 3 practices, we describe our collective experience and review the reported literature on this disorder both as an isolated condition and in conjunction with other anomalies.

RESULTS

We examined 15 fingers with dDD, 5 of which involved little fingers. We also found dDD in 6 cases with radial polydactyly (preaxial polydactyl type II [PPD2]) and in 1 case of cleft hand involving digits adjacent to the clefted web space (the index and middle fingers). Cases of little finger dDD were also associated with prominent clefting of the adjacent web space in 4 of 5 cases. All cases had stiffness of the interphalangeal joints and loss of palmar creases consistent with dorsalization of the palmar aspect of the digit. When combined with 63 fingers reported in the literature with dDD, 3 patterns were evident. The most common form occurred in little fingers (n = 50; 64%; dDDu). The next most common form was reported in association with cleft hands (n = 16; 21%; dDDc). Radial digits in association with either radial polydactyly (PPD2) or radial longitudinal deficiency were also susceptible to dDD (n = 12; 15%; dDDr).

CONCLUSIONS

Congenital dDD is a disturbance of terminal dorsal-ventral digit patterning. The distribution of this condition with little fingers, clefting, and altered radial digit formation (PPD2 or radial longitudinal deficiency), as well as recent genetic and animal studies, suggests that dDD and altered dorsal-ventral patterning are linked to abnormal apical ectodermal ridge boundary formation.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IV.

Wassel VI Duplications: A Report of 2 Cases, Soft-tissue Anatomy, and Reconstructive Approach

Preaxial polydactyly represents an embryologic failure of formation and differentiation that is most commonly classified according to the level of bony duplication. The soft-tissue anatomy and approach to reconstruction of a Wassel VI thumb, an uncommon variant in which complete duplication begins at the metacarpals has not been extensively discussed in the literature. Here, we present 2 patients with a Wassel VI duplication and a shared soft-tissue variant of anomalous insertion of the opponens pollicis muscle onto the radial hypoplastic digit. A critical component of thenar reconstruction involves preservation and reinsertion of the opponens muscle into the dominant and preserved metacarpal.

Insights into the pathogenesis and treatment of split/hand foot malformation (cleft hand/foot)

Cleft hand or split hand foot malformation is a sequence of phenotypes, from a minor shortening of the central digit to a complete absence of the third ray and in the most severe cases, absence of two, three or four rays. It is a rare but spectacular presentation usually involving both hands and feet. Inheritance is mostly autosomal dominant but sporadic cases without family history are also reported, resulting from a de novo mutation/deletion/duplication. Intra-familial clinical variability is the rule, with incomplete penetrance. X-linked or autosomal recessive inheritance has also been described. To date, seven subgroups of split hand foot malformation have been identified and seven loci are currently known. Anatomical records have enhanced our knowledge of this group of disorders of the hands and feet and allowed us to improve surgical procedures and long-term outcome.

Experimental evidence that preaxial polydactyly and forearm radial deficiencies may share a common developmental origin

Preaxial polydactyly is a congenital hand anomaly predominantly of sporadic occurrence, which is frequently associated with abnormalities of the Sonic hedgehog signalling pathway. In experimentally induced preaxial polydactyly, radial aplasia is also frequently observed. To determine if there is a correlation between preaxial polydactyly and radial aplasia, we induced ectopic Sonic hedgehog signalling during chicken limb development with application of a smoothened-agonist (SAG) or retinoic acid. Application of SAG caused malformations in 71% limbs including preaxial polydactyly (62%) and forearm abnormalities (43%). Retinoic acid application induced malformations in 56% of limb including preaxial polydactyly (45%) and forearm abnormalities (50%). Radial dysplasia and ulnar dimelia were observed in both experimental conditions. We demonstrate that ectopic Sonic hedgehog signalling may cause both preaxial polydactyly and predictable forearm anomalies and that these conditions could potentially be classified as one embryological group. We propose a unifying model based on known models of ectopic Sonic hedgehog signalling.

Classification of congenital upper limb anomalies: towards improved communication, diagnosis, and discovery

Recently the International Federation of Societies for Surgery of the Hand replaced the Swanson scheme for classifying congenital upper limb anomalies with the Oberg, Manske, Tonkin (OMT) classification. This review explores the reasons for this change after nearly 50 years of using the Swanson classification. In particular, it documents the state of our understanding regarding genetics and limb development at the time Swanson generated his classification. It also describes the continued progress in clinical genetics and developmental biology. Such progress drives the need to embrace and incorporate these changes within a new classification scheme; one that will improve communication, diagnosis, and support further discovery of the pathogenesis of congenital hand anomalies.

Surgical techniques for reconstruction of the hypoplastic thumb

The reconstruction of a congenital hypoplastic thumb usually involves release of a tight first web space, metacarpophalangeal joint stabilization, reconstruction of intrinsic muscle function, and extrinsic tendon reconstruction, as appropriate. Numerous surgical options and combinations are available, but the approaches vary among surgeons who work in the field of congenital hand surgery and the empirical evidence that allows for evaluation of the results of techniques is scarce. Both the pre-operative assessment and intra-operative findings of all thumb elements - bone, joints, and soft tissues - should be considered in the surgical decision-making and eventually define the methods of reconstruction. This article summarizes the different reconstructive options.

Peromelia - congenital transverse deficiency of the upper limb: a literature review and current prosthetic treatment

Peromelia or congenital transverse deficiency describes a truncation of the upper limb below various limb levels. Recommendations regarding treatment vary and are mainly based on expert opinions. This paper summarizes the current literature regarding the aetiology, pathogenesis and specifically treatment algorithms for children with peromelia. We performed a non-systematic review of the current literature from MEDLINE/PubMed to obtain comprehensive up-to-date information about peromelia, focusing on current recommendations for the treatment of peromelia (e.g. prosthetic fitting, external stump lengthening). The current literature lacks clear evidence as to whether prosthetic treatment is superior to prosthetic non-usage. However, based on the available studies, children with transradial or transhumeral peromelia should preferably be fitted with passive/cosmetic prostheses at the age between six and 24 months, followed by active/myoelectric devices at the age of 2.5 to four years. It remains controversial whether early myoelectric prosthetic fitting can reduce prosthesis rejection times; however, cognitive readiness and the ability to absolve a guided training programme are seen as important prerequisites for myoelectric fitting. Children with very short stumps may benefit from stump lengthening using external fixators and prosthetic modification. The treatment of children with peromelia generally requires a guided, multidisciplinary team approach. A training programme is essential to optimize individuals' performance in the execution of activities of daily living and decrease rejection risks whenever a myoelectric device is prescribed. Myoelectric fitting should preferably be commenced at no later than four years of age. However, long-term reports on the benefits of prosthetic treatment are still pending.

The missing segment of the autopod 1st ray: new insights from a morphometric study of the human hand

Whether the 1st segment of the human autopod 1st ray is a 'true' metapodial with loss of the proximal or mid phalanx or the original basal phalanx with loss of the metacarpal has been a long-lasting discussion. The actual knowledge of the developmental pattern of upper autopod segments at a fetal age of 20-22 weeks, combined with X-ray morphometry of normal long bones of the hand in the growing ages, was used for analysis of the parameters, percentage length, position of epiphyseal ossification centers and proximal/distal growth rate. The symmetric growth pattern in the fetal anlagen changed to unidirectional in the postnatal development in relation to epiphyseal ossification formation. The percentage length assessment, the distribution of the epiphyseal ossification centers, and differential proximal/distal growth rate among the growing hand segments supported homology of most proximal segment of the thumb with the 2nd-5th proximal phalanges and that of the proximal phalanx of the thumb with the 2nd-5th mid phalanges in the same hand. Published case reports of either metanalysis of 'triphalangeal thumb' and 'proximal/distal epiphyseal ossification centers' were used to support the applied morphometric methodology; in particular, the latter did not give evidence of growth pattern inversion of the proximal segment of the thumb. The presented data support the hypothesis that during evolution, the lost segment of the autopod 1st ray is the metacarpal.