Low Vitamin D Levels are Associated With Need for Surgical Correction of Pediatric Fractures

Distal Femoral Stress Fractures Has High Operation Rates in Adolescent and Young Adult Athletes

BACKGROUND

Although stress fractures of the distal femur are rare, symptoms can overlap with other peri-articular knee pathology, delaying diagnosis. Untreated stress fractures have the potential to progress into completed fractures with a higher likelihood for requiring surgery and longer recovery times in otherwise healthy adolescents and young adults. This case series represents the largest cohort of adolescent athletes with distal femoral stress fractures who presented with activity-related knee pain.

METHODS

Patients treated nonoperatively and operatively for metaphyseal distal femur stress fractures at a tertiary referral center over a four-year period were retrospectively identified from the medical record.

RESULTS

Eight patients (mean age 16.8 y; range 14 to 22 y; 87.5% male; mean body mass index [BMI] 20.9) with a total of 10 distal femur stress fractures were identified. All patients were involved in competitive sports or military training. There was an average of 3.8 encounters with a medical provider between presentation with activity-related knee pain and diagnosis with distal femur stress fracture. All except 1 patient (87.5%) were initially incorrectly diagnosed with another type of peri-articular knee pathology. Six stress fractures (60%) were treated conservatively with protected weight bearing, activity modification, and gradual return to activity. Four completed stress fractures (40%) required operative fixation-3 healed uneventfully, while 1 had an asymptomatic delayed union. Vitamin D insufficiency (<30 ng/mL) was identified in 7 of 8 patients (87.5%) and 3 patients (37.5%) had an underweight BMI (<18.5). The mean clinical follow-up was 13.1 weeks (range, 2.8 to 32.0 wk).

CONCLUSIONS

High clinical suspicion for distal femoral stress fractures is needed to avoid misdiagnosis or delayed diagnosis in young, active individuals with activity-related knee pain refractory to conservative management. In this patient population, activity-related knee pain recalcitrant to activity modification, rest, and physical therapy warrants further workup with magnetic resonance imaging and orthopaedic evaluation. Though rare, misdiagnosis can result in catastrophic fractures with prolonged rehabilitation needs. An open line of communication and streamlined access for referral between primary care providers and orthopaedic surgeons is critical in preventing misdiagnosis and delayed treatment. Furthermore, the treatment of concomitant metabolic disorders and nutritional deficiency should not be neglected when treating distal femoral stress fractures.

LEVEL OF EVIDENCE

Level-IV (case series).

Pediatric Fractures: Does Vitamin D Play a Role?

BACKGROUND

Vitamin D (25-OHD) deficiency and insufficiency are reported in about half of all children. The literature on low 25-OHD and pediatric fracture risk presents inconsistent results. This study evaluates the association between pediatric fractures and 25-OHD, parathyroid hormone (PTH), and calcium.

METHODS

This is a prospective case-control study in 2 urban pediatric emergency departments (2014-2017). Patients aged 1 to 17 requiring intravenous access were enrolled. Demographics, nutrition, and activity information were recorded and levels of 25-OHD, calcium, and PTH were measured.

RESULTS

Two hundred forty-five subjects were enrolled: 123 fractures and 122 controls. Overall, the mean 25-OHD level was 23 ng/mL±8.5: 52 (21%) of patients were 25-OHD sufficient; 193 (79%) were not. Ninety-six percent of patients with lower extremity fractures had low 25-OHD versus 77% of patients with upper extremity fractures (P=0.024). The fracture cohort was younger (P=0.002), included more males (P=0.020), and spent more time playing outdoor sports (P=0.011) than the control cohort. The 25-OHD level (fracture 22.8 ng/mL±7.6 vs. nonfracture 23.5 ng/mL±9.3, P=0.494) and median calcium level (fracture 9.8 mg/dL vs. nonfracture 10.0 mg/dL, P=0.054) were similar between cohorts. The median PTH level was higher in the fracture than the control cohort (33 vs. 24.5 pg/mL; P<0.0005); PTH was elevated to hyperparathyroidism (>65 pg/mL) in 13% of fractures and 2% of controls (P=0.006). Matched subgroup analysis of 81 fracture patients and 81 controls by age, gender, and race showed that PTH was the only variable independently associated with increased odds of fracture (odds ratio=1.10, 95% CI, 1.01-1.19, P=0.021) in a model adjusted for vitamin D sufficiency and time spent playing outdoor sports.

CONCLUSIONS

Low 25-OHD is common in children with fractures but we found no difference in 25-OHD levels between fracture and nonfracture cohorts. This research can impact evidence-based guidelines on vitamin D level screening and/or supplementation after fracture.

LEVEL OF EVIDENCE

Diagnostic level IV-case-control study.

Vitamin D-A Risk Factor for Bone Fractures in Children: A Population-Based Prospective Case-Control Randomized Cross-Sectional Study

BACKGROUND

Vitamin D is an essential component in calcium metabolism. Seasonality, advanced age, sex, dark skin pigmentation, and limited exposure to sunlight were reported as causes of vitamin D deficiency. This study aims to determine whether children with lower levels of vitamin D suffer more fractures than those with sufficient levels.

MATERIALS AND METHODS

Our institution underwent a prospective case-control randomized cross-sectional single-blinded study that included 688 children. They were split into two groups: the study group and the control group. The study group received supplements of vitamin D and calcium for 6 months. Another reference cohort was observed, which comprised 889 patients in the pediatric ward for different respiratory or gastroenterological conditions without a history of fractures. This group was used for age-sex matching tests.

RESULTS

Logistic regression showed that with every one unit increase of vitamin D level, the chance of having a middle third fracture in both bones of the forearm decreased by 7% (OR 1.07); distal third fracture incidence decreased by 1.03 times; middle third radius fracture incidence decreased by 1.03 times; distal third radius fracture incidence decreased by 1.06 times. The risk of having a distal third both-bone forearm fracture increased by 1.06 times with every year of age. Comparing the healing process, we noticed an improvement in bony callus formation for patients in the study group.

CONCLUSIONS

Dosing the serum level of 25-OH-vitamin D should be taken into consideration for pediatric low-energy trauma fractures. Supplementing with vitamin D and calcium throughout childhood can be a solution for healthy bones. Our preliminary results show that the normal level of vitamin D in children should start at 40 ng/mL.

Vitamin D Supplementation and Its Impact on Different Types of Bone Fractures

Vitamin D helps to balance the levels of calcium and phosphorus to maintain proper bone structure. It is also involved in essential biological roles and displays a wide spectrum of potential benefits in the human body. Since there are many types of fractures that occur at specific ages and due to different circumstances, the influence of vitamin D on the frequency of a particular fracture may differ. Thus, the authors investigated the possible preventive effect of vitamin D on the risks of vertebral fractures, hip fractures, stress fractures and pediatric fractures. Additional aspects of vitamin D, especially on recuperation after injures and its impact on the severity of particular fractures, were also discussed. It was suggested that vitamin D supplementation may contribute to a reduction in hip fracture risk due to reduced bone turnover, decreased frequency of falls and improved muscle function. Furthermore, vitamin D appears to lower the risk of stress fractures in athletes and military recruits. Due to a nonunified protocol design, presented investigations show inconsistencies between vitamin D supplementation and a decreased risk of vertebral fractures. However, a vitamin D preventive effect on pediatric fractures seems to be implausible.

Prevalence of Vitamin D Deficiency in Children with Fractures: Before and during the COVID-19 Outbreak

BACKGROUND

Although it is generally agreed that vitamin D is important for bone health, the role of vitamin D in preventing fractures in children and adolescents remains unclear. Therefore, this study aimed to investigate the prevalence of vitamin D deficiency and insufficiency in healthy Korean children with fractures. Our secondary aim was to compare serum vitamin D levels before and during the coronavirus disease 2019 (COVID-19) outbreak.

METHODS

We evaluated 334 patients with fractures who were surgically treated at our institution between 2018 and 2019 before the onset of COVID-19 (group I). In addition, we collected data on the serum 25(OH)D levels of 210 patients who visited our pediatric department for evaluation of short stature (group II) and the serum 25(OH)D levels of the patients with fractures during the COVID-19 pandemic period (group III). A serum 25(OH)D level of <20 ng/mL was considered deficient, between 20 and 32 ng/mL was insufficient, and ≥32 ng/mL was considered sufficient.

RESULTS

The mean age was 8.1 ± 3.5 years in group I, 8.2 ± 3.7 years in group II, and 8.6 ± 3.5 years in group III. The prevalence of vitamin D deficiency was 53.0% in group I and 32.9% in group II. The mean serum 25(OH)D level was lower in group I than in group II (20.0 ± 7.3 ng/ml vs. 23.2 ± 6.9 ng/ml, p < 0.001). The mean serum 25(OH)D level of younger patients (<10 years) in group III was lower than that of the younger patients in the prepandemic period (21.4 ± 7.2 ng/mL vs. 19.2 ± 6.8 ng/mL, p=0.037).

CONCLUSIONS

We observed a high prevalence of vitamin D deficiency/insufficiency in children with fractures who required surgical treatment. During the COVID-19 pandemic, the serum vitamin D levels became even lower, especially in younger children.

Retrospective study of patterns of vitamin D testing and status at a single institution paediatric orthopaedics and sports clinics

OBJECTIVES

There has been a recent increase in awareness of the importance of bone health in children treated by paediatric orthopaedic and sports medicine providers. The purpose of this study was to assess our utilisation of 25 hydroxy vitamin D (25(OH)Vit D) testing in the past 10 years, and to evaluate the level of 25(OH)Vit D sufficiency in various populations of patients seen.

DESIGN

This is a single site, retrospective medical record review study.

SETTING

The study took place at a single large, private, paediatric level 1 trauma teaching hospital in the Northeast USA.

PARTICIPANTS

Our internal medical records query system identified all patients who have had 25(OH)Vit D testing in the past 10 years, from 1 January 2009 to 31 December 2018. All patients included were seen on an outpatient basis at our Orthopaedic clinics.

INTERVENTIONS

No interventions for strict research, however, eligible patients have had 25(OH)Vit D testing during their standard of care treatment.

MAIN OUTCOME MEASURES

The varying number of 25(OH)Vit D testing that occurred over the study time period within Orthopaedic groups, and by Vit D levels as sufficient, insufficient and deficient. 25(OH)Vit D sufficiency was ≥30 ng/mL, insufficiency <30 ng/mL and deficiency were <20 ng/mL. Patients were stratified and analysed.

RESULTS

Between 2009 and 2018, there were 4426 patients who had 25(OH)Vit D testing. Vitamin D testing increased significantly (p<0.001) in the past 10 years. 43% of patients had sufficient 25(OH)Vit D levels, 41% had insufficient levels and 15% had deficient levels.

CONCLUSION

More frequent testing has led to an increased identification of patients with insufficient and deficient 25(OH)Vit D levels. We found over 50% of patients tested were found to have 25(OH)Vit D levels under 30 ng/mL. There should be an increased awareness of patients with orthopaedic problems who may present with 25(OH) insufficiency.

What Is New in Pediatric Bone Health

BACKGROUND

This review paper aims to report on the last 5 years of relevant research on pediatric bone health in regard to nutrition and obesity, ethnic disparities, common orthopaedic conditions, trauma, spine, and sports medicine.

METHODS

A search of the PubMed database was completed using the following terms: bone health, Vitamin D, pediatric, adolescent, sports medicine, fractures, spine, scoliosis, race, ethnicity, obesity, Slipped Capital Femoral Epiphysis, Osteogenesis Imperfecta, Duchenne's Muscular Dystrophy, neuromuscular, and cancer. Resultant papers were reviewed by study authors and determined to be of quality and relevance for description in this review. Papers from January 1, 2015 to August 31, 2020 were included.

RESULTS

A total of 85 papers were selected for review. General results include 7 key findings. (1) Obesity inhibits pediatric bone health with leptin playing a major role in the process. (2) Socioeconomic and demographic disparities have shown to have a direct influence on bone health. (3) Vitamin D deficiency has been linked to an increased fracture risk and severity in children. (4) Formal vitamin D monitoring can aid with patient compliance with treatment. (5) Patients with chronic medical conditions are impacted by low vitamin D and need ongoing monitoring of their bone health to decrease their fracture risk. (6) Vitamin D deficiency in pediatrics has been correlated to low back pain, spondylolysis, and adolescent idiopathic scoliosis. Osteopenic patients with AIS have an increased risk of curve progression requiring surgery. Before spine fusion, preoperative screening for vitamin D deficiency may reduce complications of fractures, insufficient tissue repair, loosening hardware, and postoperative back pain. (7) Increasing youth sports participation has resulted in increased bone health related injuries. However, improved understanding of Relative Energy Deficiency in Sport effects on bone health has recently occurred.

CONCLUSIONS

Increasing awareness of bone health issues in children will improve their recognition and treatment. Further research is needed on diagnosis, treatment, outcomes, and most importantly prevention of pediatric bone health diseases.

Vitamin D level and fractures in children and adolescents: a systematic review and meta-analysis

INTRODUCTION

The aim of the study was to determine the relationship between vitamin D levels and the risk of bone fractures in children and adolescents.

MATERIALS AND METHODS

PubMed, Embase, and Cochrane library databases were searched using subject and free words. The Newcastle-Ottawa scale form was used to assess literature quality. ReVman 5.2 and Stata 13.0 were used for statistical analyses. The results were expressed as the mean difference (MD)/odds ratio (OR) and 95% confidence interval (95% CI). The heterogeneity test was conducted according to I² and Q tests. Egger's test was used to evaluate publication bias.

RESULTS

Thirteen studies (3943 participants ≤ 18 years old) were included, and the quality of the literature was acceptable. Regarding the 25-hydroxyvitamin D (25OHD) level in the random effects model, the MD = - 0.12 ng/mL (95% CI: -1.93, 1.69), I² = 83%, and P < 0.00001, indicating large heterogeneity. Subgroup analyses were conducted according to vitamin D supplementation and 25OHD level, the sources of heterogeneity were not found. Regarding the proportion of subjects with vitamin D deficiency in the random effects model, OR = 1.09 (95% CI: 0.67, 1.79), I² = 79%, and P < 0.0001. By sensitivity analysis, after removing Al-Daghri's study, OR = 1.22 (95% CI: 0.96, 1.56), I² = 0%, and P = 0.64.

CONCLUSION

There is no relationship between vitamin D level and the risk of bone fractures in children and adolescents.

Association of serum 25(OH)Vit-D levels with risk of pediatric fractures: a systematic review and meta-analysis

The association between the risk of fractures and suboptimal vitamin D (Vit-D) status remains controversial in children. This meta-analysis suggested that serum 25(OH)Vit-D levels were lower in pediatric cases with fractures. 25-hydroxyvitamin D (25(OH)Vit-D) levels less than 50 nmol/L were associated with increased fracture risk in children.

INTRODUCTION

This study aimed to assess the association between serum 25(OH)Vit-D and the risk of fractures in children, and to explore the sources of heterogeneity and investigate their impact on results.

METHODS

Systematic review and meta-analysis were conducted for observational studies comparing serum 25(OH)Vit-D levels between fracture and non-fracture pediatric cases. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS).

RESULTS

Analysis on 17 case-control and 6 cross-sectional studies (2929 fracture cases and 5000 controls) suggested that 25(OH)Vit-D was lower in fracture cases than in controls (pooled mean difference (MD) = - 3.51 nmol/L; 95% confidence interval (CI): - 5.60 to - 1.42) with a heterogeneity (I²) of 73.9%. The sensitivity analysis which merged the case-control studies that had a NOS score ≥ 4 showed a pooled MD of - 4.35 nmol/L (95% CI: - 6.64 to - 2.06) with a heterogeneity (I²) of 35.9%. Pooled odds ratio of fracture in subjects with 25(OH)Vit-D ≤ 50 nmol/L compared to subjects with 25(OH)Vit-D > 50 nmol/L was 1.29 (95% CI: 1.10 to 1.53; I² < 1%).

CONCLUSION

This study indicated that serum 25(OH)Vit-D levels were lower in pediatric patients with fractures. 25(OH)Vit-D ≤ 50 nmol/L was associated with increased fracture risk in children.

Prevalence of vitamin D deficiency in children presenting with supracondylar fractures of humerus

OBJECTIVE

The purpose of the current analysis is to evaluate the predominance of vitamin D inadequacy in children with supracondylar fracture of the humerus.

METHODS

This is a cross-sectional study conducted at Dr Ruth K. M. Pfau Civil, Hospital, Karachi, Pakistan, from December 2019 to July 2020. Patients aged 18 months-18 years presenting with supracondylar fractures were included in the study. Patients were divided into four groups based on their age as toddlers (18 months to 3 years), pre-school age (3-5 years), school-age (6 to 11 years) and adolescents (11-18 years).

RESULTS

A total of 227 children presented with upper limb fractures of which 72 (31.7%) were supracondylar. The mean vitamin D level was found to be 32.5 ± 9.1 ng/mL. Of the study subjects, low vitamin D levels were found in 34.7% (n = 25), adequate in 59.7% (n = 43) and ideal in 5.5% (n = 4) of patients. The mean vitamin D levels for toddlers were 33.5 ng/mL, for preschool children was 27.66 ng/mL, for school-age children was 30.4 ng/mL and for adolescents was 37 ng/mL.

CONCLUSION

Vitamin D deficiency is not only restricted to Pakistan but also other parts of the world, although the reasons may vary in each of those regions. However, vitamin D supplementation in all parts of the globe can prevent a significant number of fractures. This prevalence study showed vitamin D deficiency in 35% of children with supracondylar fractures, with the lowest mean values in the preschool age group.

Vitamin D Status in Children With Forearm Fractures: Incidence and Risk Factors

Introduction:

The association between vitamin D status and fracture characteristics in children remains ambiguous. We hypothesized that vitamin D deficient or insufficient children would have an increased risk of forearm fractures severe enough to require surgical management.

Methods:

One hundred children with low-energy forearm fractures were prospectively enrolled from a single hospital. Each participant answered a questionnaire focusing on the risk factors for vitamin D deficiency. Fractures were categorized as requiring nonsurgical or surgical management. Vitamin D status was based on the measurement of 25-hydroxyvitamin D (25(OH)D) concentration obtained during the clinic visit and compared between the two fracture groups.

Results:

The cohort exhibited a mean age of 9.8 ± 3.2 years (range: 3-15 years), comprising 65 (65%) men and 35 (35%) women. Overall, mean 25(OH)D was 27.5 ± 8.3 ng/mL. Using the Endocrine Society guidelines, 21% of patients were categorized as “vitamin D deficient” (25(OH)D ≤ 20 ng/mL) and 49% as “vitamin D insufficient” (25(OH)D: 21 to 29 ng/mL). Stratification by intervention revealed a mean 25(OH)D of 23.3 ± 8.8 ng/mL in the surgical group (n = 12) and 28.1 ± 8.1 in the nonsurgical group (n = 88) (P = 0.057). Fifty percent of the surgical group were “vitamin D deficient” compared with 17% of the nonsurgical group (P = 0.017). The relative risk of requiring surgical treatment in children with forearm fracture and vitamin D deficiency (25(OH)D < 20 ng/mL) was 3.8. 25(OH)D level, negatively correlated with body mass index (r = −0.21, P = 0.044); 9 surgical patients were overweight or obese (as defined by the criteria of the Centers for Disease Control and Prevention). 25(OH)D level was significantly lower in non-Caucasians compared with Caucasians (26.0 ± 7.2 versus 32.5 ± 9.9 ng/mL; P = 0.0008).

Discussion:

Vitamin D deficiency is common in children with forearm fractures and may be a contributing risk factor for forearm fractures requiring surgical management in children.

Conclusion:

Vitamin D deficiency and inefficiency are common in children with low energy forearm fractures, especially in obese children and in fractures requiring surgical treatment.

Pitfalls with Vitamin D Research in Musculoskeletal Disorders and Recommendations on How to Avoid Them

Reports suggesting that vitamin D may have extraskeletal roles have renewed interest in vitamin D research and stimulated publication of an increasing number of new studies each year. These studies typically assess vitamin D status by measuring the blood concentration of 25-hydroxyvitamin D [25(OH)D], the principal circulating metabolite of vitamin D. Unfortunately, variations in assay format, inconsistency in interpreting 25(OH)D concentrations, cohort bias (age, body mass index, race, season of measurements etc.) and failure to measure critical variables needed to interpret study results, makes interpreting results and comparing studies difficult. Further, variation in reporting results (reporting mean values vs. percent of the cohort that is deficient, no clear statement as to clinical relevance of effect size, etc.) further limits interstudy analyses. In this paper, we discuss many common pitfalls in vitamin D research. We also provide recommendations on avoiding these pitfalls and suggest guidelines to enhance consistency in reporting results.

Obtaining Vitamin D Levels in Children With Fractures Improves Supplementation Compliance

BACKGROUND

Obtaining ideal serum 25-vitamin D (25VitD) levels (>30 ng/mL) is imperative in childhood to achieve peak bone mass. Supplementation compliance in children recommended to take vitamin D postfracture was evaluated. The questions we sought to answer were: Is there (1) a compliance difference between patients with known versus unknown 25VitD levels; (2) an association between compliance and age; and (3) an association between fracture severity and initial 25VitD level.

METHODS

One physician analyzed compliance in 1818 fracture patients 2 to 18 years (42% female) with known (48%) and unknown 25VitD. Patient/caregiver's self-reported adherence to supplementation as "yes" (4 d/wk minimum) or "no" defined compliance. Compliance relating to fracture severity via Abbreviated Injury Scale (AIS), 25VitD level, and age, was analyzed.

RESULTS

Patients with 25VitD levels were more compliant than patients without (61%, n=532/872; 21%, n=206/946; P<0.001). In total, 83% (n=104/125) of AIS 3 patients were compliant, compared with 49% (n=628/1292) of AIS 1/2 patients (P<0.001). Compliance increased with age (odds ratio: 1.09, 95% confidence interval: 1.061-1.120, P<0.001).

CONCLUSIONS

Compliance increased when 25VitD levels were obtained, improving with fracture severity. Clinicians should order 25VitD levels on fracture patients to improve supplementation compliance.

LEVEL OF EVIDENCE

This is a level IV prognostic study which aims to investigate the effects of various patient characteristics on compliance.

High prevalence of vitamin D insufficiency in Chinese children with upper limb fractures

This study aimed at investigating the vitamin D status of pediatric patients with upper limb fractures and finding out the influences of age, gender, season and fracture sites. 695 patients were admitted for upper limb fractures between November 1st 2014 and October 31st 2015. 224 healthy children were included during the same period. Serum 25(OH)D was measured at the time of visit and their demographic data were recorded. Generally fracture patients had significant lower vitamin D level than the healthy children. The average serum 25(OH)D of the patients was 24.5 ng/ml, compared to 28.1 ng/ml in healthy children. Vitamin D status worsened with the increase of age and adolescents had a deficiency rate of as high as 68.6%. Gender and fracture sites had no influence on vitamin D level. This study revealed high prevalence of vitamin D deficiency and insufficiency in pediatric patients with upper limb fractures. Adolescents had such high rate of vitamin D deficiency that called for vast attention.

Impact of Race Subgroups on the Assessment of Vitamin D Status in Adolescent Idiopathic Scoliosis

The authors' main objective was to demonstrate the confounding effect of combining subgroup data, specifically race, on the prevalence of vitamin D deficiency in adolescent idiopathic scoliosis (AIS). This was a retrospective chart review. Vitamin D deficiency was defined as 25-hydroxyvitamin D (25[OH]D) less than 20 ng/mL. Data were compared between white patients and black and Hispanic patients. Vitamin D status in girls with AIS was also compared with that in girls without AIS who had a history of fracture and with the medical literature to determine if deficiency in AIS was equal to or greater than other cohorts. Mean age was 13.9±2.3 years for the white girls with AIS (n=221) and 13.6±2.2 years for pooled non-whites (n=134). Significant racial differences were found that biased interpretation of the total pooled cohort. Mean 25(OH)D was 27.9±8.5 ng/mL for white girls with AIS vs 21.9±10.3 ng/mL for non-whites (P<.0001). Deficiency was present in 13.1% of white girls vs 47.8% of non-white girls (P<.0001). Compared with girls with fractures and with the published literature, the race-matched deficiency rates were not abnormally high in girls with AIS. Prevalence of deficiency was greater in non-whites with AIS than in whites. However, percent deficiency was not greater in girls with AIS than in race-matched cohorts without AIS. Without separating data by race, interpretation of vitamin D status can be confounded. [Orthopedics. 2019; 42(3):158-162.].

The Role of Vitamin D in Pediatric Orthopedics

Understanding the role of vitamin D is an important component of the proper care of the pediatric orthopedic patient. Vitamin D is an essential component of bone metabolism in the growth and development of the pediatric skeleton, which can be acutely affected by changes to the body's vitamin D, calcium, and phosphate levels, resulting in pathologic conditions such as rickets or fractures. This article reviews the main areas in which vitamin D relates to pediatric orthopedics and highlights some of the areas where future research is being directed.

Effect of vitamin D3 seasonal supplementation with 1500 IU/day in north Italian children (DINOS study)

Background

The appropriate dose of vitamin D supplementation in children is still debated. We calculated that the recommended dose of 600–1000 IU vitamin D3/day is not sufficient to reach a serum 25-hydroxyvitamin D (25-OH-D) level of at least 30 ng/ml (75 nmol/l) in north Italian children > 12 months. The aim of this study was to analyse the effect of seasonal supplementation with 1500 IU (=37.5 μg) vitamin D3/day.

Methods

DINOS (D-vitamIN Oral Supplementation) study was a pilot, monocentric, non-random case-control register study. It was conducted in a paediatric primary care setting near Padova (North Italy, 45°N latitude). The data of 203 children (girls:boys 1:1,33) aged 2–15 years, collected between November 2010 and January 2015, were analysed. Active group A (n = 82) were given 1500 IU vitamin D3/day from November to April; control Group B (n = 121) received no supplementation. The serum 25-OH-D test was part of a laboratory tests panel and performed using a chemiluminescence immunoassay method.

Results

Serum 25-OH-D mean level + standard deviation throughout the period was 32 + 13 ng/ml (80 + 32 nmol/l) in group A vs 22 + 10 ng/ml (55 + 25 nmol/l) in group B. In group A 12% had vitamin D deficiency 25-OH-D < 20 ng/ml (50 nmol/l) and 1.2% severe vitamin D deficiency 25-OH-D < 10 ng/ml (25 nmol/l). In group B 46% had vitamin D deficiency and 9% severe deficiency (P <  0.001). In group A mean levels were normal or near-normal all the year except in May. Group B reached mean 25-OH-D levels close to 30 ng/ml (75 nmol/l) only in late summer. The active group mean 25-OH-D level was normal in preschoolers and schoolers but not in adolescents. Non-white children had a three-times vitamin D deficiency probability despite supplementation.

Conclusions

Vitamin D supplementation with at least 1500 IU vitamin D3/day from November to April was found appropriate for children in North Italy. A prolongation until May could be useful. Higher doses and/or prolonged periods could be more appropriate especially in adolescents and in non-white children.

Study registration

DINOS gained the approval of Padova Ethics Committee (n. 3960/U16/2016).

Electronic supplementary material

The online version of this article (10.1186/s13052-018-0590-x) contains supplementary material, which is available to authorized users.

Epidemiology of subdural haemorrhage during infancy: A population-based register study

Objectives

To analyse subdural haemorrhage (SDH) during infancy in Sweden by incidence, SDH category, diagnostic distribution, age, co-morbidity, mortality, and maternal and perinatal risk factors; and its association with accidents and diagnosis of abuse.

Methods

A Swedish population-based register study comprising infants born between 1997 and 2014, 0–1 years of age, diagnosed with SDH-diagnoses according to the (International Classification of Diseases, 10^th version (ICD10), retrieved from the National Patient Register and linked to the Medical Birth Register and the Death Cause Register. Outcome measures were: 1) Incidence and distribution, 2) co-morbidity, 3) fall accidents by SDH category, 4) risk factors for all SDHs in the two age groups, 0–6 and 7–365 days, and for ICD10 SDH subgroups: S06.5 (traumatic SDH), I62.0 (acute nontraumatic), SDH and abuse diagnosis.

Results

Incidence of SDH was 16·5 per 100 000 infants (n = 306). Median age was 2·5 months. For infants older than one week, the median age was 3·5 months. Case fatality was 6·5%. Male sex was overrepresented for all SDH subgroups. Accidental falls were reported in 1/3 of the cases. One-fourth occurred within 0–6 days, having a perinatal risk profile. For infants aged 7–365 days, acute nontraumatic SDH was associated with multiple birth, preterm birth, and small-for-gestational age. Fourteen percent also had an abuse diagnosis, having increased odds of being born preterm, and being small-for-gestational age.

Conclusions

The incidence was in the range previously reported. SDH among newborns was associated with difficult birth and neonatal morbidity. Acute nontraumatic SDH and SDH with abuse diagnosis had similar perinatal risk profiles. The increased odds for acute nontraumatic SDH in twins, preterm births, neonatal convulsions or small-for-gestational age indicate a perinatal vulnerability for SDH beyond 1st week of life. The association between prematurity/small-for-gestational age and abuse diagnosis is intriguing and not easily understood.

Vitamin D Deficiency in Pediatric Fracture Patients: Prevalence, Risk Factors, and Vitamin D Supplementation

OBJECTIVE

Although vitamin D levels are not routinely monitored in pediatric fracture patients, identification of children with a vitamin D deficiency may be clinically relevant because of the potential role of vitamin D in fracture healing. This study aimed to determine the prevalence of vitamin D deficiency in a pediatric fracture population and to identify risk factors for deficiency.

METHODS

All pediatric patients (<18 years) who were treated for a fracture of the upper or lower extremity from September 2012 to October 2013 in the outpatient setting of a level one trauma center were included in this cross-sectional study. Vitamin D deficiency was defined as a serum calcidiol <50 nmol/L. Potential risk factors for vitamin D deficiency were analysed using multivariable logistic regression analysis.

RESULTS

A total of 108 boys (58%) and 79 girls, of a mean age 11.1 years (standard deviation 3.9), who had undergone 189 fractures were included in the study. Sixty-four children (34%) were vitamin D deficient. Of those with follow-up measurements, 74% were no longer deficient after supplementation. Vitamin D status did not influence the occurrence of complications during fracture treatment. Independent risk factors for vitamin D deficiency were older age, season (spring), and a non-Caucasian skin type.

CONCLUSION

Clinicians who treat children with a fracture should inform patients and parents on vitamin D supplementation. Vitamin D measurement and supplementation may be needed for children with a non-Caucasian skin type or for those who present with a fracture during spring months.