Self-stimulation Behavior Research Articles

Stimming as Thinking: a Critical Reevaluation of Self-Stimulatory Behavior as an Epistemic Resource for Inclusive Education

Peripheral sensorimotor stimming activity, such as rocking and fidgeting, is widely considered irrelevant to and even distracting from learning. In this critical-pedagogy conceptual paper, we argue that stimming is an intrinsic part of adaptive functioning, interaction, and cognitive dynamics. We submit that when cultural resources build from students’ own sensorimotor dynamics, rather than subjugating them to hegemonic corporeal norms, learners’ intrinsic sensorimotor behaviors may be embraced and empowered as mental activity. This call for transformative inclusive pedagogy is of particular importance for neurodivergent children whose sensorimotor engagements have historically been ostracized as disruptive. Following a conceptual analysis of stimming that builds on a range of neuro-cognitive empirical studies drawing on post-cognitivist embodied cognition theory, we imagine inclusive educational futures that disrupt sedentary instructional design to elevate minoritized learners’ sensorimotor activity. As proof of concept, we present an example inclusive embodied activity, balance board math, a pedagogical tool designed to elicit stimming as thinking. We propose a set of design heuristics for realizing stimming’s pedagogical potential.

A Case of Autism Spectrum Disorder Treated with Theridion currasavicum Prescribed on the Basis of Group Approach

Abstract Background Autism spectrum disorder (ASD) is a pervasive developmental disorder of unknown aetiology. There is a growing prevalence of ASD globally. Currently, there are no specific treatment that can address the core impairments of ASD. Case Summary A 5-year male child was brought to outpatient department with complaints of irritability, restlessness, howling, repeating words spoken to him, repeating phrases, hand flapping, self-hurting and hurting others, climbing stairs repeatedly, repeated drawing of squares everywhere, poor social interaction, poor peer-play and inappropriate playing with toys. The case was diagnosed as ASD and was assessed with the autism treatment evaluation checklist (ATEC) at baseline and follow-up visits. The case was treated with Theridion currasavicum in centesimal scale. ATEC score at baseline of 118 turned to 69 at the 12th month and 42 after 24 months of treatment. The remedy was repeated during monthly visits in ascending potencies. The child improved in the domains of social interaction, communication, repetitive stereotype movements, restricted interests and general health. The likelihood of causal relationship between intervention and outcome has been discussed as per modified Naranjo criteria for homoeopathy. This case report highlights the usefulness of the group approach and aetiological prescription as one way of arriving at the similimum in children with autism.

Challenging Case: New-Onset Hallucinations and Developmental Regression in a Child with Autism Spectrum Disorder.

Nick is a 5-year-old boy who began displaying self-stimulating behaviors and decreased social interactions shortly before turning 3 years. At the age of 3.5 years, he was diagnosed with autism spectrum disorder by a local developmental-behavioral pediatrician. His parents recall that the physician described Nick to be "high functioning" and encouraged them to expect that he would attend college and live independently as an adult. Upon receiving the diagnosis, intervention was initiated using an applied behavioral analysis (ABA) approach. With this intervention, he demonstrated initial gains in the use of complex language and improved social interactions.Concerns regarding suspected psychosis emerged just before starting kindergarten when Nick began experiencing ego-dystonic visual and auditory hallucinations. Initially, Nick verbally responded to the hallucinations and vividly described what he was experiencing. Shortly after the onset of these hallucinations, Nick experienced a significant decrease in the frequency and complexity of his expressive language and became more withdrawn. Over time, his hallucinations intensified, and his parents became increasingly fearful for his safety. Various antipsychotic and mood-stabilizing medications, steroids, and immunotherapy have been trialed with limited improvement of his symptoms.An extensive medical evaluation yielded the following:1. Magnetic resonance imaging of the brain: dilated perivascular spaces.2. Urine organic acids: ketosis and increased lactic acid.3. Antinuclear antibody: minimally positive.4. Vitamin B12: elevated.All other studies, including lumbar puncture, electroencephalogram (awake and asleep), genetic studies (chromosomal microarray, fragile X testing, and whole exome sequencing), metabolic studies, inflammatory markers, and thyroid panel, were negative/normal.Nick is enrolled in a special education classroom within a school that utilizes an ABA-based approach for all students. As part of his educational programming, he receives 25 hours of ABA in a 1:1 setting, 2 hours of speech therapy, 3 hours of occupational therapy, 1 hour of physical therapy, and 30 minutes of music therapy weekly. Current concerns include significant head-banging and thrashing before falling asleep, hyperactivity, unsafe behaviors (e.g., banging on windows, climbing high to reach desired items), aggression toward caregivers, limited ability to complete self-care tasks (e.g., personal hygiene, toileting), significant decline in expressive language, and continued response to internal stimuli.Nick's parents now present to a multidisciplinary center seeking guidance regarding additional therapies/interventions to assist in management of his current developmental and behavioral challenges as well as information regarding his expected developmental trajectory as he reaches adulthood.

Comparative analysis of self-stimulatory behaviors in ASD and ADHD

IntroductionThe phenomenon of self-stimulatory behaviors, commonly referred to as “stimming,” presents a fascinating avenue of exploration within the context of neurodevelopmental disorders. While stimming behaviors are widely associated with ASD, there is emerging evidence suggesting that individuals with ADHD may also engage in similar behaviors. This study seeks to undertake a comprehensive investigation of the neurophenomenology of stimming in individuals diagnosed with ASD and ADHD, aiming to discern potential shared and distinctive characteristics.Objectives The principal objective of this research is to conduct an intricate neurophenomenological analysis of stimming behaviors in cohorts diagnosed with ASD (n=60) and ADHD (n=60), with a concurrent control group of neurotypical individuals (n=60). The study aspires to delineate the prevalence, typology, and neurophysiological underpinnings of stimming behaviors in both ASD and ADHD populations. Moreover, this study endeavors to identify whether particular stimming behaviors exhibit differential prevalence or intensity between the two disorders.MethodsParticipants underwent rigorous neurophenomenological assessments, incorporating structured interviews, validated self-report questionnaires and direct observations. Diagnostic confirmation was established through the administration of gold-standard instruments, such as the Autism Diagnostic Observation Schedule (ADOS-2) for ASD and the Conners’ Parent Rating Scale for ADHD. Stimming behaviors were meticulously categorized (e.g., motor, vocal, sensory) and scrutinized for quantitative metrics, including frequency, duration, and complexity.Results Preliminary analyses have uncovered profound disparities in the manifestation of stimming behaviors between ASD and ADHD cohorts. Individuals with ASD displayed a significantly higher prevalence of stimming behaviors, with motor stimming predominating, followed by vocal and sensory manifestations. In contrast, individuals with ADHD exhibited a comparatively reduced frequency and intensity of stimming, primarily within the motor domain, albeit notably less elaborate. Control group participants exhibited a negligible occurrence of stimming behaviors.ConclusionsThis multidimensional exploration illuminates the nuanced neurophenomenological distinctions in self-stimulatory behaviors between ASD and ADHD. Stimming emerges as a pivotal feature in ASD, while its presence in ADHD, though discernible, is markedly attenuated. This study’s findings hold implications for precise diagnostic delineation and the prospect of personalized interventions for these complex neurodevelopmental conditions. Future avenues of research may delve into the neural substrates underpinning stimming behaviors, further enhancing our comprehension of these phenomena.Disclosure of InterestNone Declared

The correlation between brain structure characteristics and emotion regulation ability in children at high risk of autism spectrum disorder.

As indicated by longitudinal observation, autism has difficulty controlling emotions to a certain extent in early childhood, and most children's emotional and behavioral problems are further aggravated with the growth of age. This study aimed at exploring the correlation between white matter and white matter fiber bundle connectivity characteristics and their emotional regulation ability in children with autism using machine learning methods, which can lay an empirical basis for early clinical intervention of autism. Fifty-five high risk of autism spectrum disorder (HR-ASD) children and 52 typical development (TD) children were selected to complete the skull 3D-T1 structure and diffusion tensor imaging (DTI). The emotional regulation ability of the two groups was compared using the still-face paradigm (SFP). The classification and regression models of white matter characteristics and white matter fiber bundle connections of emotion regulation ability in the HR-ASD group were built based on the machine learning method. The volume of the right amygdala (R2 = 0.245) and the volume of the right hippocampus (R2 = 0.197) affected constructive emotion regulation strategies. FA (R2 = 0.32) and MD (R2 = 0.34) had the predictive effect on self-stimulating behaviour. White matter fiber bundle connection predicted constructive regulation strategies (positive edging R2 = 0.333, negative edging R2 = 0.334) and mother-seeking behaviors (positive edging R2 = 0.667, negative edging R2 = 0.363). The emotional regulation ability of HR-ASD children is significantly correlated with the connections of multiple white matter fiber bundles, which is a potential neuro-biomarker of emotional regulation ability.

Sensory Cues Potentiate VTA Dopamine Mediated Reinforcement.

Sensory cues are critical for shaping decisions and invigorating actions during reward seeking. Dopamine neurons in the ventral tegmental area (VTA) are central in this process, supporting associative learning in Pavlovian and instrumental settings. Studies of intracranial self-stimulation (ICSS) behavior, which show that animals will work hard to receive stimulation of dopamine neurons, support the notion that dopamine transmits a reward or value signal to support learning. Recent studies have begun to question this, however, emphasizing dopamine's value-free functions, leaving its contribution to behavioral reinforcement somewhat muddled. Here, we investigated the role of sensory stimuli in dopamine-mediated reinforcement, using an optogenetic ICSS paradigm in tyrosine hydroxylase (TH)-Cre rats. We find that while VTA dopamine neuron activation in the absence of explicit external cues is sufficient to maintain robust self-stimulation, the presence of cues dramatically potentiates ICSS behavior. Our results support a framework where dopamine can have some base value as a reinforcer, but the impact of this signal is modulated heavily by the sensory learning context.

Hypothalamic CRF neurons facilitate brain reward function

Aversive stimuli activate corticotropin-releasing factor (CRF)-expressing neurons in the paraventricular nucleus of hypothalamus (PVNCRF neurons) and other brain stress systems to facilitate avoidance behaviors. Appetitive stimuli also engage the brain stress systems, but their contributions to reward-related behaviors are less well understood. Here, we show that mice work vigorously to optically activate PVNCRF neurons in an operant chamber, indicating a reinforcing nature of these neurons. The reinforcing property of these neurons is not mediated by activation of the hypothalamic-pituitary-adrenal (HPA) axis. We found that PVNCRF neurons send direct projections to the ventral tegmental area (VTA), and selective activation of these projections induced robust self-stimulation behaviors, without activation of the HPA axis. Similar to the PVNCRF cell bodies, self-stimulation of PVNCRF-VTA projection was dramatically attenuated by systemic pretreatment of CRF receptor 1 or dopamine D1 receptor (D1R) antagonist and augmented by corticosterone synthesis inhibitor metyrapone, but not altered by dopamine D2 receptor (D2R) antagonist. Furthermore, we found that activation of PVNCRF-VTA projections increased c-Fos expression in the VTA dopamine neurons and rapidly triggered dopamine release in the nucleus accumbens (NAc), and microinfusion of D1R or D2R antagonist into the NAc decreased the self-stimulation of these projections. Together, our findings reveal an unappreciated role of PVNCRF neurons and their VTA projections in driving reward-related behaviors, independent of their core neuroendocrine functions. As activation of PVNCRF neurons is the final common path for many stress systems, our study suggests a novel mechanism underlying the positive reinforcing effect of stressful stimuli.

The Effectiveness of Art Therapy on Social Development in Children with Autism Spectrum Disorders

People with Autism Spectrum Disorder (ASD) are characterized by having problems with communication, behaviors, and social interactions. Art therapy (AT) is recognized as an effective way to deal with the difficulties of ASD since it is accessible and applicable. The application of AT at an early age can raise the possibility that one with ASD can improve the symptoms. Past studies suggested that two main deficits of ASD are psychosocial problems and social-reward processing problems. The mechanisms that make AT effective are still unclear. Communication, sense of self, eye contact, tolerance of unexpected consequences, establishing of social relationships, and decrease in anxiety level can support the development of social skills. Incorporating behavioral techniques into AT can exert a greater influence on the enhancement of problem behaviors. The means, goals, outcomes, and factors that work for AT are discussed and become essential elements of AT. The application of art materials, the artwork of children, and the attachment of art therapists can contribute to the progress of forming relationships, facilitating interactions, and alleviating self-stimulatory behaviors as well as anxiety levels. Follow-up observations and transformations of AT are recommended to be completed in future research. This review can provide some suggestions for the development of intervention programs at schools.

Children with Autism Spectrum Disorder Exhibit Elevated Physical Activity and Reduced Sedentary Behavior.

According to previous research, individuals with autism spectrum disorder (ASD) have lower levels of physical activity than their typically developed (TD) counterparts. There have been conflicting reports about physical activity (PA) levels in people with ASD. Given the conflicting evidence, further investigation is required. We believe that evaluating PA in individuals with ASD is critical in order to offer PA intervention plans aiming at increasing their health-related physical fitness on a daily, systematic, and individualized basis. In the current study, an ActiGraph monitor (GT3X+) was used to accurately measure PA and sedentary activity in 21 children with autism aged 6.43 ± 2.29 years and 30 TD children aged 7.2 ± 3.14 years. Our data indicated that while the light and moderate activity counts were not significantly different between the two groups, the vigorous activity was significantly higher in ASD compared to TD. This finding was attributed to ASD characteristic stereotypy and self-stimulating behaviors. The significantly higher vigorous PA is discussed in relation to altered neurochemistry, oxidative stress, and neuroinflammation as etiological mechanisms in ASD. This research provides a better understanding of the status of PA participation in individuals with ASD.

Digital skin defect management: Hand and wrist volar flap solutions

BackgroundSelecting the optimal flap for managing digit skin defects is challenging, particularly for inexperienced surgeons, given the numerous reconstructive options and insufficient evidence supporting one flap type's superiority over another. This retrospective study introduces four efficacious hand flaps to address volar skin defects and transverse and oblique cuts, examines the optimal flap advancement distance, and discusses effective management. MethodsPatients with digit skin defects who underwent flap surgery between 2009 and 2022 were included. Fifty-four patients treated with oblique triangular, volar VY advancement (unilateral and bilateral pedicled volar VY advancement flaps for fingers and thumbs, respectively), reverse homodigital island, and radial artery superficial palmar branch flaps were included. We evaluated the flap advancement distance, flap length, range of motion, complications, and Semmes–Weinstein monofilament test and Disabilities of the Arm, Shoulder, and Hand questionnaire results. ResultsThe median flap advancement distances for triangular oblique (19 patients), unilateral (11 patients), and bilateral pedicled (5 patients) volar VY advancement flaps were 1.3, 1.8, and 2.0 cm, respectively. The flap lengths for the reverse digital island (8 patients) and radial artery superficial palmar branch (11 patients) flaps were 2.4 and 5.0 cm, respectively. Five, three, and one cases of proximal interphalangeal flexion contractures of ≥ -20° were observed in the VY advancement, reverse digital island, and radial artery superficial palmar branch flaps, respectively. One unilateral VY advancement flap case caused severe numbness and neuroma. All complication cases featured >15 and > 20 mm defect lengths on the fingers and thumb, respectively. ConclusionsTo minimize sensory disruption and contractures, we recommend oblique triangular and unilateral pedicle volar VY advancement flaps for finger skin defects up to 12 mm and defects sized 12–15 mm, respectively. Advancement flaps are unsuitable for >15 and > 20–25 mm defects on the fingers and thumb, respectively.

Deep Learning Algorithms for Behavioral Analysis in Diagnosing Neurodevelopmental Disorders

Autism spectrum disorder (ASD), or autism, can be diagnosed based on a lack of behavioral skills and social communication. The most prominent method of diagnosing ASD in children is observing the child’s behavior, including some of the signs that the child repeats. Hand flapping is a common stimming behavior in children with ASD. This research paper aims to identify children’s abnormal behavior, which might be a sign of autism, using videos recorded in a natural setting during the children’s regular activities. Specifically, this study seeks to classify self-stimulatory activities, such as hand flapping, as well as normal behavior in real-time. Two deep learning video classification methods are used to be trained on the publicly available Self-Stimulatory Behavior Dataset (SSBD). The first method is VGG-16-LSTM; VGG-16 to spatial feature extraction and long short-term memory networks (LSTM) for temporal features. The second method is a long-term recurrent convolutional network (LRCN) that learns spatial and temporal features immediately in end-to-end training. The VGG-16-LSTM achieved 0.93% on the testing set, while the LRCN model achieved an accuracy of 0.96% on the testing set.

Soft tissue reconstruction with small free flaps in hand and finger defects

Soft tissue reconstruction with small free flaps in hand and finger defects

DETECTION OF AUTISM SPECTRUM DISORDER USING DEEP LEARNING

Social interaction, conduct, and cognitive ability are all impacted by the neuro developmental illness known as autism spectrum disorder (ASD). Even though ASD diagnosis can be difficult and time-consuming, early detection and intervention can improve long-term results. Early childhood is when autism spectrum disorder first manifests, and it eventually leads to issues with social, academic, and occupational functioning in society. Within the first year, autism signs are frequently visible in children. Some infants display autistic spectrum disorder symptoms as early as infancy, including decreased eye contact, a lack of responsiveness to their name, or a lack of interest in carers. To identify the presence of disorder at an early stage, use a deep learning system like LSTM. Self-Stimulatory Behaviours Dataset (SSBD) was used to collect the datasets, and video dataset was used to construct the system. The feature extraction algorithm is the Blaze Pose algorithm. The model file has been constructed, and the datasets will be trained using the deep learning technique. When a disease prediction input image is provided, the severity of the disease is determined as a result. Using the children's activity, the proposed system offers an effective way to more effectively anticipate the presence of autism spectrum disorder Key Words: Autism Spectrum Disorder, Long-Short Term Memory, Blaze Pose, Batch Normalization, ReLu, Softmax

Meningosel ve miyelomeningosel nedeni ile opere edilen 0-1 yaş çocuklarda sentetik dura ile otolog dura kullanımının komplikasyon gelişimi açısından karşılaştırılması

Abstract: Aim: The aim of this study is to compare the usage of synthetic and autologous dura mater in terms of complication risk in 0-1-year-old children who were operated for meningocele and myelomeningocele. Material and Methods: This cross-sectional observational study was conducted with 44 children aged 0-1 years who were operated for meningocele and myelomeningocele in a university hospital neurosurgery clinic between November 2010 and December 2016. Patient data were extracted retrospectively from hospital records. The demographics and gestational and clinical features of the mothers and babies, and the need for secondary surgery and the presence of postoperative infection, necrosis, wound dehiscence, and/or neurological deficit were compared between the cases who synthetic dura mater was used in their surgery and those autologous dura was used in their surgery. Results: In total, 86.4% of the 44 infants were preterm, and the predominant neurological problem was plegia in the vast majority. While the defect was located in the lumbar region in more than half of them, myelomeningocele was detected in 77.3% of all cases. The median defect size detected in the patients was 20.0 cm2, primary closure was performed in 30 patients, Limberg flap procedure in 14 patients, however, autologous dura mater and synthetic dura mater were used equally in the patients. The defect size was larger in patients using synthetic dura, furthermore hydrocephalus was found more frequently in these patients. While primary closure was applied in all patients using autologous dura and in one third of the patients using synthetic dura, Limberg flap procedure was applied in two thirds of synthetic dura group. The need for secondary surgery developed more frequently in synthetic dura group, and all postoperative complications were observed more frequently in these patients. In addition, the need for secondary surgery and postoperative necrosis, wound dehiscence, and neurologic deficit are more frequent in patients who underwent Limber flap compared to primary closure. However, the need for secondary surgery and the risk of postoperative complications were similar between primary closure and Limberg flap procedures in synthetic dura group. Conclusion: Although the synthetic dura mater was used in more severe patients, it had a higher need for secondary surgery and a higher risk of complications compared to autologous dura. In patients using synthetic dura, on the other hand, primary closure and Limberg flap had similar efficacy and safety.

Nonverbal hand movements serve self-related functions in blind individuals

ObjectiveBlind individuals suffer from visual (i.e., sensory) deprivation. So-called “blindisms” (or “nervous” movements) have been described as the nonverbal consequence of such deprivation. However, the neuropsychological functions of such behaviours of blind individuals have not been investigated yet. We therefore analyzed the nonverbal hand movement and gestural behaviour of blind individuals with the hypothesis that their nonverbal expressions rather serve their own mental state than the nonverbal (/gestural) depiction of (mental) images. MethodsThe (entire) nonverbal hand movement and gestural behaviour of right-handed healthy blind, (matched) sighted, and (matched) sighted/blindfolded individuals was analyzed during a standardized interview situation (about emotions and actions) by four independent (certified) raters employing the Neuropsychological Gesture (NEUROGES) Coding System. ResultsThe results show no difference of the overall hand movement activity between blind, sighted, and sighted/blindfolded individuals. Increased position shifts and on body focused hand movements were found in blind individuals when compared to sighted and sighted/blindfolded individuals. Sighted but neither blind nor sighted/blindfolded individuals increase egocentric deictic and pantomime gestures during the re-narration of an audio story. DiscussionBlind individuals seem to desynchronize during conversation (shifts), increase self-stimulation behaviour due to sensory deprivation (on body), but reduce the nonverbal transfer of mental images via hand gestures. We therefore conclude that nonverbal hand movements of blind individuals rather serve their own mental state but not for the transfer of mental images.

The use of a picture activity schedule for vocal stereotypy reduction in a child with autism

Children with ASD exhibit auto-stimulatory behaviour of different types, with the most common behavioural problem being auto-stimulatory stereotyped behaviour. It is believed that vocal auto-stimulatory behaviour occurs because the individuals with ASD do not receive sufficient stimulation from their environment and therefore have the need to stimulate themselves by emitting vocal stereotypy of different form and magnitude. The participant is a 10-year-old boy diagnosed with ASD. The intervention used was a picture activity schedule. Results showed an immediate decrease in self-stimulatory behaviour upon implementation of the intervention, with a 100% success rate. There is insufficient research on the implementation of picture activity schedules in order to reduce self-stimulatory behaviour in children with ASD. The present study shows that picture activity schedules can be used in certain situations where it is inappropriate to exhibit self-stimulating behaviour. It is not certain if the picture activity schedule functioned as a prompt for the participant to actively engage in his spare time, or if it functioned as a discriminative stimulus for situations when the problem behaviour is inappropriate. The social validity of the intervention was discussed, as well as suggestions for future research implementation.

Maladaptive Attachment and Emotional Intelligence: A Comparative Study Between Married and Unmarried Group

The purpose of the study was to find out the Relationship between Emotional Intelligence and Depression. The study was conducted on the sample of 90 people aged between 18-40 years. The sample included 45 Married Individuals and 45 Unmarried Individuals. The sampling method that was used was Purposive sampling. The following study attempts to show the relationship of Emotional Intelligence and Maladaptive Attachment. The emotional intelligence is defined in terms of self- control, well-being, sociability, Emotionality. Emotional Intelligence (EI) includes the capacity to known and manages emotions of one’s own self and also to deal effectively with others. Emotions significantly influence the relationship that is present between people. Maladaptive behaviors targeted in ABA (Applied Behavior Analysis) can include extreme tantrums, excessive and interfering self-stimulating behaviors, feeding limitations, aggression, self injury, elopement (running away) and sleep interfering behaviors. Hence, it was found that there exists both negative and positive correlation between and within both the groups married and unmarried.

Gesticulation in individuals with at risk mental states for psychosis

Nonverbal communication (NVC) is a complex behavior that involves different modalities that are impaired in the schizophrenia spectrum, including gesticulation. However, there are few studies that evaluate it in individuals with at-risk mental states (ARMS) for psychosis, mostly in developed countries. Given our prior findings of reduced movement during speech seen in Brazilian individuals with ARMS, we now aim to determine if this can be accounted for by reduced gesticulation behavior. Fifty-six medication-naïve ARMS and 64 healthy controls were filmed during speech tasks. The frequency of specifically coded gestures across four categories (and self-stimulatory behaviors) were compared between groups and tested for correlations with prodromal symptoms of the Structured Interview for Prodromal Syndromes (SIPS) and with the variables previously published. ARMS individuals showed a reduction in one gesture category, but it did not survive Bonferroni’s correction. Gesture frequency was negatively correlated with prodromal symptoms and positively correlated with the variables of the amount of movement previously analyzed. The lack of significant differences between ARMS and control contradicts literature findings in other cultural context, in which a reduction is usually seen in at-risk individuals. However, gesture frequency might be a visual proxy of prodromal symptoms, and of other movement abnormalities. Results show the importance of analyzing NVC in ARMS and of considering different cultural and sociodemographic contexts in the search for markers of these states.

A new circuit underlying the renewal of appetitive Pavlovian responses: Commentary on Brown and Chaudhri (2022).

A new circuit underlying the renewal of appetitive Pavlovian responses: Commentary on Brown and Chaudhri (2022).

Mathematical analysis in the design of digital artery-based V–Y advancement flap in treating proximal interphalangeal joint flexion contracture

BackgroundThe digital artery-based V–Y advancement flap is a widely used flap for soft tissue coverage in the treatment of flexion contracture of the proximal interphalangeal (PIP) joint. A standard method for the flap design and a mathematical method to predict the advance distance have not been well established. In this study, we proposed a simplified method for the design of V–Y advancement flaps based on digital arteries and used a geometric model to predict the advance distance for the flexion contracture correction surgery.MethodsAccording to the general concept of hand flap design and law of cosine, we proposed three principles in the design of the digital artery-based V–Y advancement flap that should be followed. Since 2021 to 2022, finger geometric data of 120 fingers (index, middle, ring, and small fingers) from 30 healthy participants were collected and analysed to evaluate the necessary advance distance and flap tip angle for PIP flexion contracture correction of different fingers by our flap design method.ResultsThe middle finger needed a significantly longer advance distance compared to other fingers in the same degree flexion contracture correction. The ring finger had the largest length-to width ratio and smallest flap tip angle among the four fingers in the V–Y flap design. No vertical scar crossed the flexion creases and flap tip angle < 20° was found in the tentative V–Y flap design for the 120 fingers.ConclusionsOur flap design method provides a proper advance distance and flap length-to-width ratio without common skin complications in the flap design for PIP flexion contracture of index, middle, ring and small fingers. This geometric model provides a mathematical basis for prediction of advance distance and flap tip angle in the design of a digital artery-based V–Y advancement flap.