Parental experience after diagnosis of a congenital upper limb difference: a national survey.

Congenital hand and upper limb differences may be detected during antenatal ultrasonography or visually at birth. We investigated the experience of parents when they first learned that their child had an upper limb difference. This national retrospective cross-sectional quantitative and qualitative survey within the UK and Ireland received 261 responses from parents of children. Differences were first suspected antenatally among 41% of respondents and in 57% postnatally, with 2% unsure. Of the children, 54% were seen in a clinic by a specialist congenital hand surgeon within 3 months and 88% within 12 months, with 73% of respondents feeling unsupported after a diagnosis that was unexpected. Qualitative analysis outlined a broad spectrum of parental concerns about the quality of information received, especially regarding the child's future biopsychosocial needs. This study showed the need for more support for parents from frontline healthcare professionals and the need for a streamlined referral pathway.Level of evidence: IV.

The association between trauma and paediatric trigger thumb deformity; experience from a single tertiary referral hospital.

Whilst the natural history and management of trigger thumb have been thoroughly investigated, the aetiology of the condition remains poorly understood. There are suggestions that this could be a congenital or acquired condition, but evidence remains limited. A history of trauma has repeatedly been noted in a proportion of patients presenting with trigger thumb. This retrospective study reviewed the presentations of 75 cases of trigger thumb in 65 consecutive children who underwent surgery for trigger thumb. We found that 28% of affected digits presented with a traumatic history to the thumb, of those 90% presented immediately post-injury with a flexion deformity. Those who presented with a traumatic history were typically younger at presentation (median age 27.0 months compared to 37.5 months for traumatic and atraumatic presentations respectively) but also tended to present earlier than the atraumatic group (one day compared to 12.17 months respectively). We conclude that a single traumatic event is unlikely to be the causative factor in the development of trigger thumb in children but it may expediate the development of individuals who are predisposed.

The importance of embryology for parents of children with congenital hand differences.

This study aimed to determine whether embryology knowledge or explaining the possible developmental pathway error was important for parents of affected children, and to secondarily determine if there was a relationship between desired knowledge of embryology and disease severity, maternal age group or maternal level of education. Using a self-administered questionnaire, a significant proportion of responding parents considered knowledge of embryology important (32 out of 43). We found a significant association between the importance of embryology knowledge for parents and the disease severity. However, the importance and level of knowledge desired was not related to maternal age or level of education. This study demonstrated the importance of explaining the associated developmental errors in the congenital hand consultation, particularly in severe anomalies. Surgeons should familiarize themselves with embryology to provide an explanation as to why congenital hand differences happen, which may provide better psychological support for parents of these children.

Revisiting the dogma of the Edinburgh position for safe immobilization.

Since the concept was first described 50 years ago in Edinburgh by J. I. P. James, the term 'Edinburgh position' has been synonymous with the position of safe immobilization for the hand. Widely employed for the management of injured hands, the position is associated with splinting the metacarpophalangeal joints at 90° and the proximal interphalangeal joints completely straight, namely, 'the intrinsic-plus position', to help reduce the long-term consequences of a stiff hand. Over the decades, the strict joint angles of the Edinburgh position have been debated due to changes in patterns of injury, treatment and rehabilitation. This article challenges the dogma that surrounds the use of the Edinburgh position in clinical practice. The history of the position was explored, and the results of a survey about current practice of hand immobilization from two study centres in Edinburgh is presented.Level of evidence: IV.

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.

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.