Adverse Childhood Experiences and Education Outcomes among Adolescents: Linking Survey and Administrative Data

It is well established that adverse childhood experiences (ACEs) are associated with detrimental health outcomes in adulthood. Less is known about the relationships between ACEs and education outcomes and among adolescents. The aim of this study was to examine the associations between ACEs and adolescents' self-reported education outcomes and provincial education assessments among adolescents in Manitoba, Canada. Data were gathered from 1002 adolescents who participated in the Well-Being and Experiences (WE) Study. A subsample of the adolescents (84%) consented to having their WE survey data linked to administrative education databases. Binary and multinomial logistic regression models were computed to examine associations between ACE history and self-reported education outcomes and provincial education assessments, adjusting for sociodemographic variables. Adolescents with an ACE history had significantly increased likelihood of having ever been suspended from school (adjusted odds ratio (aOR) = 3.33, 95% CI 1.60-6.92), of lower grades (adjusted relative risk ratio (aRRR) = 3.21, 95% CI 1.42-7.29), and of chronic school absenteeism (aRRR = 2.45, 95% CI 1.28-4.68) compared with adolescents without an ACE history after adjusting for sociodemographic variables. Findings from this study illuminate the important relationship between childhood adversity and poor education outcomes assessed directly by adolescents. Increasing awareness of the public health risk associated with ACEs and education outcomes may inform education policy and school-based interventions.

Associations between Lifetime Spanking/Slapping and Adolescent Physical and Mental Health and Behavioral Outcomes

BACKGROUND

Many parents use physical forms of punishment, including spanking to correct perceived misbehavior. While some authors suggest spanking/slapping is a distinct and "milder" form of physical punishment, parents' use of spanking is consistently associated with poor outcomes for their children. However, less is known about the relationship between spanking/slapping and health and behavioral outcomes in adolescence independent of other childhood adversities.

OBJECTIVES

The objectives of this study were to examine the associations between lifetime experiences of spanking on the bottom and/or slapping on the hand and 3 adolescent outcomes: (a) mental health disorders, (b) physical health conditions, and (c) defiant behaviors, after adjusting for other types of childhood adversities and child maltreatment.

METHODS

Cross-sectional data from the provincially representative 2014 Ontario Child Health Study (N = 6,537 dwellings, response rate = 50.8%) were used. The current study focused on one selected child aged 14 to 17 years within a household (n = 1,883) with data collected from the adolescent and the parent/caregiver. Logistic regression models were used to identify associations with lifetime experiences of spanking/slapping 3 or more times (vs. 0 to 2 times).

RESULTS

Lifetime spanking/slapping was independently associated with increased odds of mental health disorders, physical health conditions, and defiant behaviors in adolescence after adjusting for childhood adversities and child maltreatment (unadjusted and adjusted odds ratios ranging from 1.29 to 2.19).

CONCLUSIONS

These findings suggest that lifetime spanking/slapping is uniquely associated with harmful mental, physical, and behavioral outcomes in adolescence, and efforts should focus on its prevention.

Adverse childhood experiences (ACEs) research: A bibliometric analysis of publication trends over the first 20 years

BACKGROUND

The relative health and robustness of a field of research can be approximated by assessing peer reviewed journal publication trends for articles pertinent to the field. To date, there have been no such assessments of the burgeoning research on adverse childhood experiences (ACEs).

OBJECTIVE

The overall goal of this study was to examine ACEs research trends using bibliometric methods. More specifically, we sought to describe observed publication trends of the ACEs literature from its inception in the late 1990s. We also analyzed the nature of ACEs publications with regard to key characteristics of main outcomes, levels of analysis, and populations of primary focus.

METHODS

A search was conducted using Scopus to identify English language papers on ACEs published in peer-reviewed journals between 1998 and 2018. The primary field of research was determined by having independent raters code the title of the publishing journal into distinct categories. Main research outcomes were similarly coded.

RESULTS

A total of 789 articles on ACEs appearing in 351 different academic journals were published between 1998 and 2018. There was considerable growth in the number of ACEs papers published over the past several years. General medicine and multidisciplinary research were the most frequent of 12 primary fields of research characterizing ACEs research. Of 16 primary outcomes on which ACEs research focused, the most common were mental health and physical health.

CONCLUSION

Significant growth in ACEs research over the past several years suggest the field is thriving. Observed publication trends and publication characteristics are discussed briefly.

Building Research Capacity and Organizational Empathy Among Students: Making Connections Beyond the Data

IntroductionThe leveraging of multi-sector, whole-population, linked administrative data is advantageous for conducting research on complex real-world problems. However, such large and complex data repositories can sometimes appear impersonal and overwhelming. Establishing organizational empathy (OE) in thecontext of a multi-sector partnership between academic, government and community representatives can help us understand the data better for social policy research. Evidence stemming from this research can then inform policy decisions, ultimately increasing the potency of linked data analysis and creating more meaningful student experiences. Our objective is to examine the role of OE in the student research experience. Objectives and ApproachSPECTRUM (Social Policy Evaluation Collaborative Team Research at Universities in Manitoba) is a multi-disciplinary partnership working to provide evidence-based solutions to ‘wicked’ social issues by using linked data from multiple sectors. SPECTRUM provides fellowships to students to become partners in the collaboration. Students have participated in quarterly workshops, building relationships with community leaders, government decision-makers and academic researchers. Students are from various faculties, bringing their unique frameworks and research interests to the collective. Through OE, students observeand participate in SPECTRUM, relating its goals and outcomes to society and their own research. ResultsStudent inclusion in SPECTRUM enhances the partnership by providing a greater range of perspectives and facilitates the development of OE among SPECTRUM members. Students are using linked administrative data, while actively engaging in dialogue with stakeholders, thereby enriching their knowledge and understanding of research. Conclusion / ImplicationsData linkage involves more than just use of the repository; it requires establishing common ground since the data have different meaning to each partner. OE developed through SPECTRUM provides invaluable insight into and context for the data. Knowledge transfer among members of the partnership will enrich SPECTRUM’s research outcomes while building capacity among Students.

Evaluating Full Day Kindergarten – Is It Associated with Improved Short- And Long-Term Education Outcomes Among Metis Children?

IntroductionEarly education outcomes influence children’s educational trajectories with long-term effects extending into adulthood. Aboriginal peoples face numerous systemic barriers to academic success. It remains unknown if full-day kindergarten (FDK) is associated with improved academic outcomes among Metis children – a distinct Aboriginal people recognized by the Canadian Constitution. Objectives and ApproachThe Manitoba Metis Federation and the Manitoba Centre for Health Policy partnered to identify whether FDK was associated with improved short- and long-term outcomes among Metis children. We created a cohort of Metis children by linking several provincial databases held in the Manitoba Population Research Data Repository (1998-2011). Education data were used to identify all Metis children who attended FDK (n=247) vs half day kindergarten (HDK; n=547). FDK children were matched by age and sex to children in HDK. We used a step-wedged design and applied propensity scores to adjust for measured confounding. We tested for differences in grades 3, 7, 8 outcomes and high school graduation using generalized linear models. ResultsFDK children were more likely to live in a low-income neighbourhood. 72% FDK and 74% HDK students met or approached numeracy expectations in grade 3; and 55% FDK and 48% HDK met or approached numeracy expectations in grade 7. For reading expectations, 77% FDK and 75% HDK met or approached grade 3 reading expectations; in grade 8, 62% in each group met or approached expectations for reading and writing. High school graduation rate for FDK children was 84% and for HDK children was 64%. After adjusting for confounding we found FDK children were more likely to graduate high school than HDK children; other outcomes were non-significant. Conclusion / ImplicationsKindergarten programs may be insufficient to overcome structural barriers that Metis children face. Culturally appropriate education strategies are needed to support improved outcomes amongst this population.

Evaluation of The Manitoba Healthy Baby Prenatal Benefit: Is It Improving Birth and Early Childhood Outcomes for Metis Families?

IntroductionIn Manitoba, low-income pregnant women are eligible for the Healthy Baby Prenatal Benefit (HBPB), a prenatal income supplement. Research has demonstrated positive outcomes associated with HBPB, but it remains unknown if Metis women and children – who are of mixed European and Aboriginal descent and one of the most marginalized populations in Canada -- benefit from the program. Objectives and ApproachThe Manitoba Metis Federation and the Manitoba Centre for Health Policy partnered to determine the impact of HBPB on Metis newborn and early childhood outcomes. We included all Metis women giving birth in Manitoba 2003-2011 who received income assistance during pregnancy (n=4,852), adjusting for differences between those receiving (n=3,681) and not receiving (n=1,171) HBPB with propensity score weighting. We used multi-variable regressions to compare outcomes between groups: breastfeeding initiation, low birth weight, preterm birth, small- and large-for-gestational age, Apgar scores, birth hospitalization length of stay (LOS), neonatal readmissions, infant hospitalizations, vaccinations at age 1 and 2, and child development scores at kindergarten. ResultsHBPB receipt was associated with reductions in low birth weight (adjusted Relative Risk (aRR): 0.74 (95% CI: 0.58-0.94)) and preterm births (aRR: 0.78 (0.65-0.94)), and increases large-for-gestational age births (aRR: 1.21 (1.06-1.39)) and neonatal readmissions (aRR: 1.58 (1.05-2.37)). Birth hospitalization LOS was lower for newborns whose mothers received HBPB (Mean Difference 0.29 days). HBPB was associated with increases in vaccinations for children aged 1 (aRR: 1.08 (1.00-1.15)) and 2 (aRR: 1.12 (1.05-1.18)). No significant associations were found for small-for-gestational age births, Apgar scores, breastfeeding initiation, infant hospitalizations or child development scores. Conclusion / ImplicationsA modest unconditional prenatal income supplement to low-income Metis women was associated with improved birth outcomes and child vaccinations; however, an association with increased neonatal readmissions warrants further exploration. Lack of significant associations between HBPB and child development measures suggests more sustained support may be necessary to improve longer-term outcomes.

What type of survey research questions are identified by adults as upsetting? A focus on child maltreatment

BACKGROUND

Research on child maltreatment is imperative to inform evidence-based prevention and intervention efforts. Nonetheless, researchers continue to face barriers due to the perceived sensitivity and possibility of harm when asking about these experiences. While studies have started to explore reactions to participating in research on sensitive topics, there are notable limitations and fewer have focused on child maltreatment.

OBJECTIVE

The objective of this study was to better understand adult respondents' identification of, and reactions to, potentially upsetting questions in the context of a well-being and experiences survey, with a focus on child maltreatment.

METHODS

Data were from the first wave of the Well-Being and Experiences Study in Manitoba, Canada: a computerized self-reported community-based survey of adolescents and their parents/caregivers administered individually at a research facility. The current study focused on parents/caregivers' responses (N = 1000). The study utilized a mixed methods approach with descriptive statistics and qualitative thematic analyses of open-ended responses of their perceptions of upsetting questions.

RESULTS

Overall, few respondents (15.1 %) identified any questions as upsetting. Ten themes emerged in respondents' recall of upsetting questions, including maltreatment and other themes often perceived as less sensitive. Only 4% identified maltreatment-related questions as upsetting. Among those who identified any questions or maltreatment-specific questions as upsetting, most felt they were important to ask and should not be removed (92.7 %-97.5 %). These findings suggest that retrospective survey questions about experiences of child maltreatment involving adult samples are not associated with major upset and should be included in future health and social surveys.

Adverse childhood experiences (ACEs), peer victimization, and substance use among adolescents

BACKGROUND

Adverse childhood experiences (ACEs) are common and related to substance use problems in adulthood. Less is known about these relationships in adolescence and if experiencing ACEs in addition to peer victimization (or bullying) would have an interaction or cumulative effect on the odds of adolescent substance use.

METHOD

Data were used from the Well-Being and Experiences Study (The WE Study), a cross-sectional survey of adolescents aged 14-17 years (n = 1002) in Manitoba, Canada collected between July 2017 and October 2018. Statistical methods included descriptive statistics and logistic regression models.

RESULTS

The prevalence of experiencing any of the 12 ACEs was 75.1 %. The prevalence of any peer victimization (monthly or more often) was 24.1 %. All individual ACEs were associated with increased odds of substance use. No significant interaction effects between ACEs and peer victimization on substance use were found. Significant cumulative effects were found, indicating that experiencing both ACEs and peer victimization, compared with experiencing ACEs only, significantly increased the odds of substance use among adolescents.

CONCLUSION

The odds of substance use becomes significantly greater if the adolescent with a history of ACEs also experiences peer victimization. Further research aimed at effective prevention of ACEs, peer victimization, and substance use is needed.

In Utero Antidepressants and Neurodevelopmental Outcomes in Kindergarteners

OBJECTIVES

To determine if in utero selective serotonin reuptake inhibitor (SSRI) or selective serotonin norepinephrine inhibitor (SNRI) exposure is associated with developmental vulnerability in kindergarten among children whose mothers were diagnosed with prenatal mood or anxiety disorder.

METHODS

Linkable administrative data were used to create a population-based cohort of 266 479 mother-child dyads of children born in Manitoba, Canada, between 1996 and 2014, with follow-up through 2015. The sample was restricted to mothers who had a mood or anxiety disorder diagnosis between 90 days before conception (N = 13 818). Exposed women had ≥2 SSRI or SNRI dispensations during pregnancy (n = 2055); unexposed mothers did not have a dispensation of an SSRI or SNRI during pregnancy (n = 10 017). The Early Development Instrument (EDI) was used to assess developmental health in kindergarten children. The EDI is a 104-component kindergarten teacher-administered questionnaire, encompassing 5 developmental domains.

RESULTS

Of the 3048 children included in the study who met inclusion criteria and had an EDI, 21.43% of children in the exposed group were assessed as vulnerable on 2 or more domains versus 16.16% of children in the unexposed group (adjusted odds ratio = 1.43; 95% confidence interval 1.08-1.90). Children in the exposed group also had a significant risk of being vulnerable in language and/or cognition (adjusted odds ratio = 1.40; 95% confidence interval 1.03-1.90).

CONCLUSIONS

Exposure to SSRIs or SNRIs during pregnancy was associated with an increased risk of developmental vulnerability and an increased risk of deficits in language and/or cognition. Replication of results is necessary before clinical implications can be reached.

Confirmatory factor analysis of adverse childhood experiences (ACEs) among a community-based sample of parents and adolescents

Background

Despite increased understanding of Adverse Childhood Experiences (ACEs), very little advancement has been made in how ACEs are defined and conceptualized. The current objectives were to determine: 1) how well a theoretically-derived ACEs model fit the data, and 2) the association of all ACEs and the ACEs factors with poor self-rated mental and physical health.

Methods

Data were obtained from the Well-Being and Experiences Study, survey data of adolescents aged 14 to 17 years (n = 1002) and their parents (n = 1000) in Manitoba, Canada collected from 2017 to 2018. Statistical methods included confirmatory factor analysis (CFA) and logistic regression models.

Results

The study findings indicated a two-factor solution for both the adolescent and parent sample as follows: a) child maltreatment and peer victimization and b) household challenges factors, provided the best fit to the data. All original and expanded ACEs loaded on one of these two factors and all individual ACEs were associated with either poor self-rated mental health, physical health or both in unadjusted models and with the majority of findings remaining statistically significant in adjusted models (Adjusted Odds Ratios ranged from 1.16–3.25 among parents and 1.12–8.02 among adolescents). Additionally, both factors were associated with poor mental and physical health.

Conclusions

Findings confirm a two-factor structure (i.e., 1) child maltreatment and peer victimization and 2) household challenges) and indicate that the ACEs list should include original ACEs (i.e., physical abuse, sexual abuse, emotional abuse, emotional neglect, physical neglect, exposure to intimate partner violence (IPV), household substance use, household mental health problems, parental separation or divorce, parental problems with police) and expanded ACEs (i.e., spanking, peer victimization, household gambling problems, foster care placement or child protective organization (CPO) contact, poverty, and neighborhood safety).

Child maltreatment and sleep problems among adolescents in Ontario: A cross sectional study

INTRODUCTION

Child maltreatment has a negative impact on health and well-being. Healthy sleep patterns are an important indicator of health and are particularly important for adolescent growth and development. Few studies examine the relationship between child maltreatment and sleep problems using a general population, adolescent sample. The objective of the current study was to examine the relationship between five different types of child maltreatment and four sleep outcomes among adolescents.

METHODS

Data were from a subset of the Ontario Child Health Study 2014, a representative sample of 14 to 17- year-olds in Ontario, Canada (n=2,910). Sexual abuse, physical abuse and exposure to intimate partner violence (EIPV) were measured using the Childhood Experiences of Violence Questionnaire (CEVQ). Emotional maltreatment and physical neglect were measured using items derived from survey questions designed for the National Longitudinal Study of Adolescent to Adult Health. Sleep outcomes included time it takes to fall asleep, waking during the night, and hours of sleep on weekdays and weekends. Models were adjusted for sociodemographic variables.

RESULTS

Findings indicate that all types of child maltreatment were associated with increased odds of taking more than 10 min to fall asleep (adjusted odds ratio [AOR]: 1.21-1.58), waking more often during the night (AOR: 1.62-5.73) and fewer hours slept on weekdays (adjusted beta [AB]: -0.39 to -0.15). Child sexual abuse, emotional maltreatment, and EIPV were associated with decreased hours of sleep on weekends (AB: -0.63 to -0.28).

CONCLUSION

Preventing child maltreatment may improve sleep outcomes among adolescents, thereby improving overall health and well- being.

Examining the relationships between parent experiences and youth self-reports of slapping/spanking: a population-based cross-sectional study

Background

Slapping/spanking is related to a number of poor health outcomes. Understanding what factors are related to the increased or decreased use of spanking/slapping is necessary to inform prevention. This study used a population-based sample to determine the prevalence of slapping/spanking reported by youth; the relationship between sociodemographic factors and slapping/spanking; and the extent to which parental exposures to victimization and maltreatment in childhood and current parental mental health, substance use and family circumstances, are associated with youth reports of slapping/spanking.

Methods

Data were from the 2014 Ontario Child Health Study, a provincially representative sample of households with children and youth aged 4–17 years. Self-reported lifetime slapping/spanking prevalence was determined using a sub-sample of youth aged 14–17 years (n = 1883). Parents/primary caregivers (i.e., person most knowledgeable (PMK) of the youth) self-reported their own childhood experiences including bullying victimization, slapping/spanking and child maltreatment, and current mental health, substance use and family circumstances including mental health functioning and emotional well-being, alcohol use, smoking, marital conflict and family functioning. Analyses were conducted in 2018.

Results

Living in urban compared to rural residence and family poverty were associated with decreased odds of slapping/spanking. PMK childhood experiences of physical and verbal bullying victimization, spanking, sexual abuse, emotional abuse, and exposure to physical intimate partner violence were associated with increased odds of youth reported slapping/spanking (adjusted odds ratio [AOR] ranged from 1.33–1.77). PMK experiences of physical abuse and exposure to emotional/verbal intimate partner violence in childhood was associated with decreased odds of youth reported slapping/spanking (AOR = 0.72 and 0.88, respectively). PMK’s higher levels of marital conflict, languishing to moderate mental health functioning and emotional well-being, and moderate or greater alcohol use were associated with increased odds of youth reported slapping/spanking (AOR ranged from 1.36–1.61).

Conclusions

It may be important to consider parent/primary caregiver’s childhood experiences with victimization and maltreatment along with their current parental mental health, substance use and family circumstances when developing and testing strategies to prevent slapping/spanking.

Trauma Exposure, DSM-5 Post-Traumatic Stress Disorder, and Sexual Risk Outcomes

INTRODUCTION

The current study examined associations between DSM-5 post-traumatic stress disorder (PTSD) and three sexual risk outcomes: presence of a sexually transmitted disease/infection, frequency of condom use, and sex with a known user of injection drugs.

METHODS

Data were from the National Epidemiologic Survey on Alcohol and Related Conditions-III (2012-2013, analyzed 2017), a nationally representative survey of non-institutionalized U.S. adults aged ≥18 years. Sexual outcomes and trauma exposure were assessed via self-report, and PTSD was assessed using a validated structured interview. Logistic and multinomial regression analyses examined associations between PTSD, PTSD symptom clusters, trauma type, and each sexual outcome.

RESULTS

Lifetime PTSD was associated with increased odds of having a past-year sexually transmitted disease/infection and sex with a known injection drug user (AOR=1.54 and 1.74, respectively); fewer intrusion symptoms were associated with sometimes/fairly often condom use relative to very often. Reporting of adult sexual assault, assaultive violence, and other trauma as one's worst event was associated with increased odds of a past-year sexually transmitted disease/infection (AOR range, 1.69-4.56), whereas child maltreatment was associated with using condoms never/almost never in the past 12 months (AOR=1.40). No other significant findings emerged.

CONCLUSIONS

The current study demonstrates an association between certain trauma exposures, PTSD symptoms, and an increased likelihood of sexual risk outcomes. Clinicians working with individuals with PTSD symptoms, particularly those who have been exposed to interpersonal trauma, should screen for the presence of these sequelae.

Thymidylate synthase gene expression in solid tumors predicts for response to pemetrexed in vitro

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Background: Pemetrexed (P) is a novel antifolate which targets thymidilate synthase (TS), dihydrofolate reductase (DHFR), and glycinamide ribonucleotide formyltransferase (GARFT). The aim of the present study was to identify gene expression thresholds for these enzymes in human tumor specimens in order to separate P-sensitive from P-resistant patients. Methods: Soft-agar cloning assays were performed on freshly biopsied tumor cells exposed one hour to clinically achievable concentrations of P. In parallel, RNA was isolated, transcribed to cDNA and subsequently used for multiplex real-time PCR. Gene expression data were normalized against beta-actin transcripts followed by correlation against cloning assay results. Iterative calculations (fourfold analysis) were done for each enzyme separately to find the best cutoff for prediction of sensitivity to P. Results: Sensitive and resistant tumor samples were statistically significant different in gene expression of TS, DHFR, and GARFT (p < 0.003). 81% of all tumors with a TS copy number < 144 (related to 104 copies β-actin) were sensitive to P in vitro. (specificity = 0.69; chi2 = 14.14). Statistical tests demonstrated that gene expression of TS, DHFR, and GARFT are dependent variables and that TS transcription is the leading variable. The combination of TS, DHFR, and GARFT expression data was not superior to TS alone. Conclusions: TS expression is the most meaningful predictor for sensitivity (≤ 144 copies) or resistance (> 144 copies) to Pemetrexed in fresh tumor tissue. This observation forms a rationale for clinical trials using TS expression as predictor for clinical response.

No significant financial relationships to disclose.

In vitro chemosensitivity against enzastaurin correlates with gene expression of IL8 and GSK3-beta

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Background: Enzastaurin (E) is an active antitumoral agent which selectively inhibits the β-isoform of protein kinase C (PKC-β). The compound blocks the enzyme’s ATP-binding site and signal transmission is abrogated resulting in the inhibition of neovascularization. The aim of the present study was to correlate gene expression with in vitro chemosensitivity of freshly explanted human tumor specimens. Such correlations in tumors taken directly from patients will help to rationally design subsequent clinical trials. Methods: Soft-agar colony forming assays were performed on freshly biopsied tumor cells exposed to various concentrations of E. Corresponding pieces of tumor specimens were shock-frozen and prepared for RNA isolation and cDNA generation followed by multiplex real-time PCR experiments. Gene expression data were correlated against cloning assay results. Results: Gene expression data of PKC-β1, PKC-β2, IL8RA, IL8RB, IL8, GSK3-β, and TGF-β were correlated against in vitro chemosensitivity pattern of E from 66 samples. After 1h-drug exposure gene expressions in sensitive versus resistant specimens were statistically significant with p = 0.013 for IL8 [median copy number (mcn): 1881 vs. 694; n = 66] and p = 0.012 for GSK3-beta (mcn: 1.6 vs. 7.0; n = 66). No correlation was detected for PKC-β1, PKC-β2, IL8RA, and IL8RB. Detection of TGF-β failed in most samples. Conclusions: Low expression of GSK3-β and high expression of IL8 correlate statistically significantly with increased in vitro sensitivity to E in freshly explanted human tumors. These findings may help direct further clinical development of this compound.

No significant financial relationships to disclose.

[Examination of commercial hedgehog feed for its quality (acceptance, digestibility, and nutritional composition)]

Six commercial hedgehog feedstuffs were evaluated (palatability, composition and digestibility of crude nutrients and minerals). 14 healthy adult hedgehogs were fed these products and one self mixed diet based on minced beef and egg. The composition of all commercial diets was very similar. The components used mostly were cereal products but also animals like insects and prawns were seen. Gross energy was between 1.9 and 2.3 MJ/100 g DM. The concentrations of the minerals were partly very low (Ca, P) and in some products the relation between Ca and P was unsuitable. Even with individual differences between the animals the palatability of the self mixed diet was generally higher. Contrary to the self mixed diet the digestibility of crude protein of the commercial feed was moderate (93 vs. 73-77%). Crude fat was highly digestible (80-92%). In spite of a low activity of amylase in pancreas and chyme the digestibility of the nitrogen free extracts was very high (67-86%), probably due to thermal processing of the cereals. Since crude fibre has a negative effect on total digestibility (r = -0.78) its concentration should be under 3% in the whole diet. The average net absorption rates of minerals were: Ca: +/-0%; P: 50%; Mg: 24%; K: 85% and Na: 80%. Based on this knowledge first recommendations for the composition of nutritionally balanced complete feeds are given.

Femur lengthening with a vascularized tibia bone flap

A vascularized tibial bone flap based on a single nutrient vessel has been previously proposed for use in long-bone reconstruction. While the routine use of the tibia for donor bone tissue is precluded by its essential weight-bearing function, in select cases it provides a useful alternative to standard donor bone sources. Cadaver dissection was performed to confirm the endosteal and periosteal vascular anatomy of the tibia. The presence of a consistent nutrient vessel was confirmed. Selective dye injection demonstrated a dual cortical blood supply based on both the endosteal nutrient vessel and multiple periosteal perforator vessels. Inclusion of both vascular supplies maximizes perfusion of bone and periosteum, thus potentially optimizing bone healing and osseous union. Based on these findings, the vascularized tibial bone flap was applied to a clinical case. A 45-year-old male veteran sustained a right proximal femur fracture in a motor vehicle accident. Multiple attempts at fusion with open reduction, internal fixation, grafting, and nonvascularized fibular onlay strut with cerclage wires were all unsuccessful. The patient presented with a chronic right femur nonunion with painful pseudoarthrosis; frozen knee joint; and an internally rotated, 20.3-cm shortened, nonfunctional lower limb. Femur length proximal to the nonunion was less than 15 cm. A maximum amputation stump length is recommended for optimal prosthetic function. A 15-cm pedicled tibial bone flap based on the posterior tibial endosteal and periosteal vascular supply was reversed and plated to the proximal femur to provide a stump of adequate length to optimize prosthetic fitting and function. The tibia is essential for normal weight-bearing, but in select cases may be sacrificed for use in long-bone reconstruction. Expanded use of tibial vascularized allografts in long-bone reconstruction may be made possible following future development of effective and safe immunosuppressive therapy. Transfer based on the posterior tibial pedicle, which includes the endosteal nutrient vessel as well as the periosteal supply via the tibialis posterior muscle, maximizes bone perfusion. The pedicle is of sufficient length to be used for positioning the tibia in the thigh or for free transfer to distant sites.