Pediatric Foot: Development, Variants, and Related Pathology.

Pediatric foot development throughout childhood and adolescence can present a diagnostic dilemma for radiologists because imaging appearances may be confused with pathology. Understanding pediatric foot development and anatomical variants, such as accessory ossification centers, is essential to interpret musculoskeletal imaging in children correctly, particularly because many of these variants are incidental but others can be symptomatic. We first briefly review foot embryology. After describing common accessory ossification centers of the foot, we explain the different patterns of foot maturation with attention to irregular ossification and bone marrow development. Common pediatric foot variants and pathology are described, such as tarsal coalitions and fifth metatarsal base fractures. We also discuss pediatric foot alignment and various childhood foot alignment deformities.

Short Report: 10-year follow-up of a boy with ARID1B-related disorder. Early intervention, longitudinal dimensional phenotype, brain imaging and outcome.

ARID1B-related disorders constitute a clinical continuum, from classic Coffin-Siris syndrome to intellectual disability (ID) with or without nonspecific dysmorphic features. Here, we describe an 11-year-old boy with an ARID1B mutation whose phenotype changed from severe developmental delay and ID to a complex neurodevelopmental disorder with multidimensional impairments, including normal intelligence despite heterogeneous IQ scores, severe motor coordination disorder, oral language disorder and attention-deficit/hyperactivity disorder. Phenotypic changes occurred after early intensive remediation and paralleled the normalization of myelination impairments, as evidenced by early brain imaging. WHAT THIS PAPER ADDS?: This report describes a 10-year multidisciplinary follow-up of a child with an ARID1B mutation who received early intensive remediation and whose phenotype changed during development. Clinical improvement paralleled the normalization of myelination impairments. This case supports a dimensional approach for complex neurodevelopmental disorders.

Ankle and Foot Deformities in Children.

Ankle and foot deformity is one of the most common musculoskeletal disorders in children and a leading cause of functional impairment and diminished quality of life when not treated. A spectrum of conditions may produce foot and ankle deformities, with congenital disorders the most frequent cause, followed by acquired conditions. Congenital disorders include congenital talipes equinovarus or congenital clubfoot, metatarsus adductus, skewfoot, congenital vertical talus, and tarsal coalition.Some of these deformities are frequent and easily diagnosed based on clinical features, but clinical overlap between pathologies can be challenging. Thus imaging plays a paramount role in evaluating these patients. Radiographs are the first imaging modality of choice, but they may not be sufficient in infants due to the lack of ossification of the tarsal bones. Ultrasonography allows not only a detailed visualization of the cartilaginous structures but also permits a dynamic study of the foot and ankle. Computed tomography may be necessary in certain conditions such as tarsal coalitions.

Results of treatment of congenital vertical talus by the Dobbs method.

Congenital vertical talus is a rare foot deformity. The hindfoot is valgus and equinus, the midfoot is dorsiflexed and forefoot is abducted due to a fixed dorsal dislocation of the navicular on the head of the talus and the cuboid on the anterior part of the calcaneus. The epidemiology and etiology of vertical talus is unknown. Dobbs et al. (J Bone Joint Surg Am 88(6):1192-200, 2006) described a minimally invasive alternative which allowed to avoid the need for extensive soft tissue release procedures in treatment of congenital vertical talus. Eleven congenital vertical talus feet (group 5 according to Hamanishi) in eight children (four boys and four girls) constituted the study material. Upon the diagnosis, the patients' age ranged from 5 to 26 months old (the mean - 14.6). The treatment involved serial manipulation and casting according to the reverse Ponseti method (from 4 to 7 casts) followed by a minimally invasive approach consisting in temporary stabilization of the talonavicular joint with the use of K-wire and Achilles tenotomy according to the Dobbs technique. Then patients continued the shoe and bar program for 2 years. The X-ray measurements on lateral radiographic included the talocalcaneal angle, tibiotalar angle and talar axis-first metatarsal base angle whereas AP radiographic images-the talocalcaneal angle and talar axis-first metatarsal angle. The Wilcoxon test was used to compare dependent variables. The final clinical assessment made during the last follow-up (the mean: 35.8 months, the range: 25-52) revealed that neutral position of the foot and normal range of motion were observed in ten cases and recurrence of foot deformity in one case. The last X-ray examination showed normalization all of radiological parameters, except for one case, and examined parameters were statistically significant. The minimally invasive technique described by Dobbs should be the first option in treatment of congenital vertical talus. It allows to reduce the talonavicular joint, brings good results and preserves foot mobility. The attention should be put on early diagnosis.

The Prevalence of Bunions in the Setting of Brachymetatarsia.

Brachymetatarsia is caused by premature closure of the physis and is characterized by a short metatarsal. Additional foot conditions may exist in patients presenting with brachymetatarsia, such as hallux valgus (HV). A retrospective study was performed to evaluate the prevalence of HV and brachymetatarsia in the ipsilateral foot. Ninety-seven feet with congenital brachymetatarsia were reviewed in a multi-study cohort of 66 patients who underwent surgical correction between January 2005 and August 2020 at a single institution. The group was comprised of 61 females and 5 males, with a mean age of 27 years. HV deformities were verified with standardized anteroposterior radiographs. HV was present in 29 of 97 feet for a prevalence of 30% in the feet with brachymetatarsia. Our results demonstrate a 30% prevalence of HV associated with brachymetatarsia. This information is helpful for foot and ankle surgeons managing brachymetatarsia to determine appropriate conservative or surgical management of this condition.

Brachymetatarsia: A Classification for Surgical Treatment.

Brachymetatarsia is a congenital osseous and soft tissue deformity of a ray(s) of the foot. Because there is no particular consensus of methodology of lengthening for brachymetatarsia, the authors introduce a comprehensive anatomic classification and a surgical guide to treatment of each classification type. This classification combines the number of the metatarsal(s) affected and the letter(s) indicating the type of brachymetatarsia deformity (A = axial deficiency of the metatarsal, B = bowing of the metatarsal, C = congruency of metatarsal phalangeal joint). This study reviewed of 300 brachymetatarsals in 166 patients. Fifty of the 166 (30%) patients had bilateral brachymetatarsia. Of the 300 metatarsals with brachymetatarsia, 64 (21%) were first metatarsals, 22 (7%) were second metatarsals, 28 (9%) were third metatarsals, 12 (4%) were fifth metatarsals, and 174 (58%) were fourth metatarsals. Classification types that were found was a total of 165 (55%) type A, a total of 6 (2%) type B, a total of 72 (24%) type AB, a total of 39 (13%) type AC, and a total of 18 (6%) type ABC. A total of 16 (10%) male and 150 (90%) female patients were evaluated. The mean preoperative amount of shortening of the metatarsal was 15 mm (range, 4-20 mm), as determined by the preoperative metatarsal parabola deficiency, equating to 30% of the preoperative metatarsal length. Brachymetatarsia is a complex congenital deformity which until now has not been critically analyzed. This study outlines a comprehensive brachymetatarsia classification system which provides an accurate diagnosis of the deformity and offers a surgical treatment algorithm.

The Role of the Shortened Proximal Phalanx in the Setting of Brachymetatarsia.

Brachymetatarsia is a condition in which a metatarsal bone does not grow out to full length. This is caused by premature physeal closure. The proximal phalanx associated with the shortened metatarsal helps achieve the natural parabola of the foot. A hypoplastic proximal phalanx is a common finding in patients with brachymetatarsia. The goal of this study was to determine the length of the proximal phalanx in the setting of brachymetatarsia, and how much the shortening is attributed to the clinically smaller toe. We performed a retrospective study to evaluate the length of the proximal phalanx in the shortened ray. After the metatarsal was brought out to the desired length of correction, the proximal phalanx was measured on radiographs. Ninety-seven feet with congenital brachymetatarsia were reviewed in a cohort of 66 patients who underwent surgical correction between January 2005 and February 2020 at a single institution. The group was comprised of 61 females and 5 males, with a mean age of 27.5 years. The average length of the proximal phalanx associated with the affected metatarsal was noted to be 18.9 ± 3.83 mm for males and 15.6 ± 4.02 mm for females. Our results indicate the shortened proximal phalanx is 5 mm shorter when compared to normal population and is a contributing factor to the shortened clinical appearance of the digit in brachymetatarsia. Treating surgeons should be aware of this to better educate patients on the influence of the digit on the overall shortening seen in cases of brachymetatarsia.

Subacute two stage metatarsal lengthening with gradual distraction for brachymetatarsia: A consecutive case series and literature review.

BACKGROUND: This study examined the functional and clinical outcomes of subacute two stage metatarsal lengthening with gradual distraction for brachymetatarsia. This technique was developed to overcome the disadvantages of one-stage metatarsal lengthening and gradual distraction. METHODS: Four feet of three patients with congenital brachymetatarsia underwent subacute two stage metatarsal lengthening with gradual distraction. Pain, function, and alignment were assessed preoperatively and at follow-ups using the American Orthopaedic Foot and Ankle Society (AOFAS) lesser metatarsophalangeal-interphalangeal scale, and any complications were recorded. RESULTS: The patients were followed up for a mean of 18.1 ± 6.9 (range, 12.6-28.1) months. The mean metatarsal length gain was 15.2 ± 3.2 (range, 12.1-18.5) mm, and the corresponding percent increase was 32.5 % ± 7.0 % (range, 25.7-41.1 %). The mean AOFAS score (0-100) was 97.5 ± 5.0 at the final follow-up. The external fixator index was 10.2 ± 1.5 (range, 8.1-11.6) days/cm. None of the patients experienced metatarsophalangeal stiffness, subluxation or dislocation of the metatarsophalangeal joint, loss of correction, pin tract infection, delayed union, nonunion, or angular deformities. CONCLUSION: Subacute two stage metatarsal lengthening with gradual distraction is a reliable alternative treatment for brachymetatarsia.

Aetiology, diagnosis, and treatment of brachymetatarsia: a narrative review.

Brachymetatarsia (BM), or hypoplastic metatarsal, is an abnormal shortening of one or more metatarsal bones with a female-to-male ratio of 10.53:1. Different causes are described in the literature, such as congenital, acquired, or iatrogenic, associated with different conditions and syndromes. Its presence may develop deformity and pain; however, often feet are pain free and the major worries of patients are cosmetics. Non-operative treatments aim to improve the comfort of metatarsal heads and the possible dorsal conflict through comfortable shoes or the use of specific orthotics. The surgical treatment is anything but straightforward, with "one-stage" or "two stage" techniques, the latter better called "by gradual distraction". One-stage procedures are more rapid techniques but have limited ability to restore the desired length due to neurovascular compromise caused by acute lengthening. Insufficient correction is also possible. On the contrary, by gradual distraction procedures allow gradual distraction lengthening of more than 1.5 cm, but require the use of an external fixator, with a higher risk of complications in more than about 50% of surgeries. The adjacent metatarsal shortening should be considered in combination with other techniques, to diminish the excessive lengthening. In each case, surgeries should be always decided on each patient's concerns, deformities, and clinical needs.

Surgical management of an isolated symptomatic talonavicular coalition: a paediatric perspective.

Talonavicular (TN) coalition is a rare pathological union of the talus and navicular bones. We report the case of a 7-year-old girl with a symptomatic TN coalition, who underwent operative management with a lateral column lengthening procedure using autologous iliac crest bone grafting. There are no complications to report and the graft was incorporated at an early stage. At 3 year follow-up the patient has remained pain-free since the operation and maintained alignment. To our knowledge, this is the first reported case of TN coalition treated with reconstructive surgery in a paediatric patient.

Natural Progression and Symptomatic Management of Tarsal-Carpal Coalition Syndrome: A Case Report.

CASE: Tarsal-carpal coalition syndrome (TCCS) is a disorder identified by fusion of the carpals, tarsals, and phalanges of the hands and feet. We describe a case of an 11-year-old girl who has been followed at our outpatient clinic from the age of 8 months. CONCLUSION: Although patients with TCCS can experience a wide range of symptoms, the primary complaint arises from the foot deformity and associated pain. Using advanced imaging such as 3D computed tomography reconstruction and genetic testing, this report details the clinical, genetic, and radiographic characteristics of the disorder. We highlight the natural progression and symptomatic management of TCCS.

Lateral Column Lengthening for Flexible Flat Foot: Was It Short to Begin With?

BACKGROUND: Flexible flatfoot (FF) is a common foot deformity that can often consist of foot pain. Surgical treatment is designed to lengthen the lateral column. OBJECTIVES: To resolve whether radiographic standing feet measurements of normo-plantigrade feet and FF, symptomatic or not, differ and to determine whether the lateral column is shorter. METHODS: The study comprised 72 patients (127 feet) consecutive patients, 18 years of age and older, who were divided into three groups: normal feet (56), asymptomatic FF (29), and symptomatic FF (42). All patients had a standing anterior posterior (AP) and lateral radiographs. AP images were used for the measurement of the talocalcaneal angle, talar-1st metatarsal angle, and talonavicular coverage. Lateral X-rays were used to estimate the talocalcaneal angle, talar-1st metatarsal angle, calcaneal pitch, naviculocuboid overlap, and column ratio. RESULTS: All three of the AP radiograph measurements differed among groups, and higher values were measured in the symptomatic FF group. Post hoc analysis found that the talonavicular coverage and the talocalcaneal angles also differed between symptomatic and asymptomatic FF patients. While some lateral measurements differed within groups, only the lateral talar-1st metatarsal angle distinguished between asymptomatic and symptomatic patients. The lateral column length was not found to be shorter among FF patients, weather symptomatic or not. CONCLUSIONS: Only the talonavicular coverage, the AP talocalcaneal, and the lateral talar-1st metatarsal angles were found to differ between asymptomatic and symptomatic FF patients. The lateral column was not found to be shorter.

Nonincisional Osteotomy for Gradual Lengthening by Callus Distraction for Congenital Brachymetatarsia.

Gradual lengthening by distraction osteogenesis is widely used for congenital brachymetatarsia. The usual presenting complaint is the patient's cosmetic appearance. Osteotomy is an integral element. A nonincisional surgical approach for osteotomy can reduce dorsal longitudinal scarring and help preserve the periosteal blood supply to the bone during surgical dissection. Between June 2003 and January 2019, we performed gradual lengthening by callus distraction with nonincisional osteotomy for congenital brachymetatarsia on 13 digits in 5 patients. All 5 patients were female, and their average age was 18 years old. The lengthened bones involved 3 first metatarsals, 2 third metatarsal, and 8 fourth metatarsal bones. The mean gain in length was 15.2 mm (10-21 mm). The mean duration of distraction was 36.2 days (30-48 days). The mean duration of consolidation was 62.8 days (28-103 days). The lengthened segment consolidated in all cases. One patient had early consolidation and did not wish to undergo further surgery. There were no cases of trouble due to drilling for osteotomy. All patients had a normal gait and were satisfied with the cosmetic results.

Outcomes of a Minimally Invasive Approach for Congenital Vertical Talus With a Comparison Between the Idiopathic and Syndromic Feet.

BACKGROUND: Congenital vertical talus (CVT) is a rare congenital foot disorder. Approximately half of the affected children have associated neuromuscular syndromes which may further complicate the treatment. The traditional treatment involved extensive soft tissue and bony reconstructions. The minimally invasive method (Dobbs method/reverse Ponseti) has changed the treatment of CVT. There is significant variation of the reported outcome of this method in the current literature. In this study we report the outcome of this minimally invasive technique for treatment of CVT and compare the results of treatment in syndromic and idiopathic patients. METHODS: Idiopathic and syndromic patients treated from CVT with minimally invasive method from 2006 till 2016 were included in this retrospective study. We reviewed the patients' notes, radiographs and collected parents reported outcome questionnaire (Roye score) in addition to clinical examination to comprehensively report the treatment outcome. RESULTS: A total of 21 patients 30 feet were included in this study. The average age of commencing treatment was 6 months (1 to 17 mo). The mean follow-up was 6.5 years (1 to 11 y). Correction of the deformities and abnormal angles were achieved in all feet. Five of the 17 syndromic feet had recurrence while no recurrence was reported in any if the 13 idiopathic feet. At the time of the index procedure no supplementary procedures were required. The average arc of motion for foot ankle dorsiflexion and plantar flexion was 30 degrees. Patients with idiopathic CVT had a mean the Roye score of 11 while syndromic patients had a mean score of 22. CONCLUSION: The minimally invasive method is a valuable option for treatment of CVT. Idiopathic patients had no recurrence and better functional scores compared syndromic patients. There was no requirement for supplementary procedures such as tibialis anterior transfer or anterolateral release at the time of the initial surgery. LEVEL OF EVIDENCE: Level IV-case series.

Clinical characteristics of 93 cases of isolated macrodactyly of the foot in children.

BACKGROUND: The purpose of this study was to describe the clinical characteristics of macrodactyly of the foot through a large cohort of cases to further understand this rare entity. METHODS: Medical records, clinical photographs, plain radiographs, pathological findings, and intraoperative photographs of 95 feet of 93 patients were reviewed. Data including age; sex; laterality; ethnicity; birthplace; family history; and history of gestation, environment, whether smoking, or drinking during pregnancy were collected and analyzed. RESULTS: Female patients (60%), left foot (56%), and static overgrowth (63%) were more prominent in the study cohort. Southern provinces (74%) and Han Chinese ethnicity (95%) predominated in terms of geographical region and demographic distribution, respectively. Multiple-toe involvement was 2.01-times more frequent than single-toe involvement. All five toes were involved with midline toes being most frequently affected overall and a medial distribution being more common than a lateral one. The forefoot was affected in 90 feet. The affected areas (toes and forefeet) were mostly located in the innervation of the affected medial plantar nerve (91%). The nerves showed enlargement in 49 feet, fatty infiltration in 25, a tortuous course in one, and were normal in 10 feet. Only six feet involved the musculature. Enlargement of phalanges and metatarsals were observed in 92 and 57 feet, respectively, and advanced bone maturation was seen in 63 feet. Twenty-two cases had syndactyly. CONCLUSIONS: Macrodactyly of the foot is a rare congenital malformation with diverse clinical manifestations and multiple elements' involvement. It also presents the characteristics of nerve-mediated overgrowth and "nerve territory-oriented" deformity similar to that of macrodactyly of the hand.

Macrodactyly of the foot resulting from plantar nerve impairment.

The role of the plantar nerve in the pathogenesis of macrodactyly of the foot is unknown. We investigated the distribution of affected toes and forefoot in 27 feet of 26 patients with pedal macrodactyly, and how this relates to innervation of the affected plantar nerve. A preoperative ultrasound examination was performed to determine the diameter and structure of the plantar nerve. Histologic findings were recorded during surgery. The microstructure of affected plantar nerves was evaluated by hematoxylin-eosin staining, while S100 expression was assessed by immunofluorescence analysis. Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) gene mutation in the affected nerve tissue was detected by Sanger DNA sequencing. The affected toes and forefoot involved innervation of the medial plantar nerve in 25/27 feet, the lateral plantar nerve in one foot, and both medial and lateral plantar nerves in one foot. All affected plantar nerves, which were accompanied by a fatty strip, were surrounded by or infiltrated with fat. The affected plantar nerves showed enlargement, a tortuous course, fatty infiltration, or a combination of these. Pathologic changes in affected plantar nerves involved only the epineurium and not the perineurium or endoneurium. Expression of the Schwann cell marker S100 was absent in some areas of affected nerves. Sequencing of PIK3CA exons identified a gain-of-function mutation (p.His1047Arg) in affected plantar nerves. These results indicate that pathologic impairment of the plantar nerve can lead to macrodactyly of the foot, which may be considered as a nerve trunk disease.

Value of ultrasonography and radiography for the study of bone regeneration in lengthening of the fourth ray in brachymetatarsia.

BACKGROUND: Distraction osteogenesis is frequently used for brachymetatarsia. METHODS: Brachymetatarsia of the fourth ray was treated with the Ilizarov method in 10 females. Distraction rate was 1.00-0.75mm a day. Radiography and ultrasonography were used to study the regeneration course throughout the distraction and fixation phases. RESULTS: Mean lengthening achieved was 2.28cm in the average distraction period of 30.2 days and average fixation phase of 50.2 days. Ultrasonography detected the regeneration signs and zonal structure of the regenerate earlier than radiography. It confirmed slow regeneration in two patients and their distraction rate was corrected. One patient had premature consolidation on distraction day 10 and needed re-osteotomy. CONCLUSIONS: Combination of radiography and ultrasonography to study bone regeneration in brachymetatarsisa provides a better monitoring of distraction callus progression. Ultrasonography is of great value to detect regeneration problems during early stages of lengthening.

Carpenter syndrome in a patient from Tanzania.

Carpenter syndrome (acrocephalopolysyndactyly type II) is a rare autosomal recessive disorder. It was clinically diagnosed in a female baby with polysyndactyly and craniosynostosis in a referral clinic in Northern Tanzania. In the RAB23 gene, a previously described homozygous variant c.82C>T p.(Arg28*) was detected that results in a premature stop codon. Both parents were demonstrated to be heterozygous carriers of this variant. Herewith, its pathogenicity is proved. A literature search suggests this is the first molecularly confirmed case of Carpenter syndrome in continental Africa.

Is foot deformity associated with developmental dysplasia of the hip?

AIMS: To assess if congenital foot deformity is a risk factor for developmental dysplasia of the hip (DDH). METHODS: Between 1996 and 2012, 60,844 children were born in Sør-Trøndelag county in Norway. In this cohort study, children with risk factors for DDH were examined using ultrasound. The risk factors evaluated were clinical hip instability, breech delivery, a family history of DDH, a foot deformity, and some syndromes. As the aim of the study was to examine the risk for DDH and foot deformity in the general population, children with syndromes were excluded. The information has been prospectively registered and retrospectively analyzed. RESULTS: Overall, 494 children (0.8%) had DDH, and 1,132 (1.9%) a foot deformity. Of the children with a foot deformity, 49 (4.3%) also demonstrated DDH. There was a statistically significant increased association between DDH and foot deformity (p < 0.001). The risk of DDH was highest for talipes calcaneovalgus (6.1%) and club foot (3.5%), whereas metatarsus adductus (1.5%) had a marginal increased risk of DDH. CONCLUSION: Compared with the general population, children with a congenital foot deformity had a significantly increased risk for DDH and therefore we regard foot deformity as a true risk factor for DDH. Cite this article: Bone Joint J 2020;102-B(11):1582-1586.

Congenital radioulnar synostosis presenting in adulthood - a case report.

Congenital radioulnar synostosis is a rare developmental skeletal malformation of the upper limb, characterized by the fusion of the proximal ends of the radius and ulna from birth. The failure of prenatal longitudinal segmentation of the adjacent radius and ulna results in a fibrous bony bridge between the radius and ulna. We present a 23-year-old female who presented with pain and restricted mobility of the left elbow joint for 7 years. A plain X-ray was performed for the patient, revealing a diagnosis of congenital radio-ulnar synostosis. Careful evaluation of the anatomical relations and spatial orientation of bony structures is required for the diagnosis and treatment of such cases.