Non-accidental injury: confusion with temporary brittle bone disease and mild osteogenesis imperfecta

Multiparametric Classification of Skin from Osteogenesis Imperfecta Patients and Controls by Quantitative Magnetic Resonance Microimaging

The purpose of this study is to evaluate the ability of quantitative magnetic resonance imaging (MRI) to discriminate between skin biopsies from individuals with osteogenesis imperfecta (OI) and skin biopsies from individuals without OI. Skin biopsies from nine controls (unaffected) and nine OI patients were imaged to generate maps of five separate MR parameters, T₁, T₂, k_m, MTR and ADC. Parameter values were calculated over the dermal region and used for univariate and multiparametric classification analysis. A substantial degree of overlap of individual MR parameters was observed between control and OI groups, which limited the sensitivity and specificity of univariate classification. Classification accuracies ranging between 39% and 67% were found depending on the variable of investigation, with T₂ yielding the best accuracy of 67%. When several MR parameters were considered simultaneously in a multivariate analysis, the classification accuracies improved up to 89% for specific combinations, including the combination of T₂ and k_m. These results indicate that multiparametric classification by quantitative MRI is able to detect differences between the skin of OI patients and of unaffected individuals, which motivates further study of quantitative MRI for the clinical diagnosis of OI.

Evaluating children with fractures for child physical abuse

Fractures are common injuries caused by child abuse. Although the consequences of failing to diagnose an abusive injury in a child can be grave, incorrectly diagnosing child abuse in a child whose fractures have another etiology can be distressing for a family. The aim of this report is to review recent advances in the understanding of fracture specificity, the mechanism of fractures, and other medical diseases that predispose to fractures in infants and children. This clinical report will aid physicians in developing an evidence-based differential diagnosis and performing the appropriate evaluation when assessing a child with fractures.

Skeletal trauma in child abuse

Fractures and other skeletal injuries are common in childhood. Most are the result of falls, motor vehicle accidents, and other forms of accidental trauma. However, skeletal trauma is present in a significant number of abused children. Age and developmental abilities are key components in raising clinical suspicion for child abuse. Children who are unable to provide their own history because of age or developmental delay require increased attention. Younger children are more likely to have abusive fractures, whereas accidental fractures increase with age and developmental abilities. The consequences of missing abuse are high because children returned to their homes without intervention are likely to face further abuse and have an increased mortality risk. Because of the potentially high cost of undiagnosed child abuse, diagnosis of a skeletal injury is incomplete without diagnosing its etiology. All health providers for children should be able to recognize patterns of skeletal injury secondary to abusive trauma and understand the process for initiating Child Protective Services (CPS) investigations when necessary. Although they can occur accidentally, fractures in nonmobile children should always increase the clinician's concern for abusive trauma. In light of the significant consequences for children when abuse is missed by a primary care provider, abuse should be on the differential diagnosis for all presenting childhood injuries.

Osteogenesis imperfecta misdiagnosed as child abuse

The differential diagnosis of child abuse includes osteogenesis imperfecta (OI). Mild phenotypes of OI may be misdiagnosed as child abuse. The purpose of this study was to review the experience of families in which OI was misdiagnosed as child abuse. Sixty-one potential cases of misdiagnosis were identified from a lay support organization. Upon review of the medical records, 33 cases were identified with a confirmed diagnosis of OI (skin biopsy or DNA blood test). Questionnaires were given to families to describe their condition and experiences. There were 19 male and 14 female children. Mean age at presentation was 7.1 months (range: 1-23 months). All patients had fractures and the presenting symptoms included pain (n=14), swelling (n=7), decreased limb movement (n=5), or unusual limb position (n=2). Abnormal radiograph findings consistent with OI were found in 19 of 33 patients (58%), clinical findings of OI were present in 23 of 33 patients (70%), and a family history that could be supportive of OI was present in 18 of 33 families (55%). Children were removed from the family in 70% of cases and older siblings were removed from the family in 62% of cases. The mean age at the time of diagnosis of OI was 10.5 months (range: 3-35 months). The consequences of misdiagnosis of OI as child abuse are devastating to the family. OI should be considered in all cases of suspected child abuse. In children with any clinical, radiographic, or family history features of OI, early involvement of a bone specialist and performance of laboratory testing should be considered to establish a timely and accurate diagnosis.

The radiographic approach to child abuse

BACKGROUND

Osseous injuries are a major facet of child abuse and in most patients radiographic imaging plays a major role in diagnosis. While some injuries are typically produced as a result of excessive and inappropriate force other injuries are nonspecific in terms of their causation, but become suspicious when the history provided by the caretakers is inconsistent with the type of injury produced.

QUESTIONS/PURPOSES

I detail the radiographic imaging of the more characteristic of the highly specific injuries, discuss the major issues that relate to some moderate- or low-specificity injuries, and describe several diseases that mimic abuse.

METHODS

A review of the current and recent literature focused on the radiographic imaging of child abuse was performed by searching the National Library of Medicine database at pubmed.gov. Keywords used included: radiology, fracture, child abuse, and/or nonaccidental trauma.

RESULTS

Injuries that are highly specific for the diagnosis of abuse include metaphyseal corner fractures, posteromedial rib fractures, and sternal, scapular, and spinous process fractures. Lesions of moderate specificity include, among other injuries, multiple fractures of various ages and epiphyseal separations. Long-bone fractures and clavicular fractures, while common, are of low specificity. In addition to the appropriate accurate diagnosis of these injuries, several diseases and syndromes may mimic abuse due to the similarity in the radiographic picture.

CONCLUSIONS

Stratification of fractures sustained in child abuse according to specificity and an understanding of the several diseases that mimic abuse are helpful in the accurate diagnosis of child abuse.

LEVEL OF EVIDENCE

Level V, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Diagnostic imaging of child abuse

The role of imaging in cases of child abuse is to identify the extent of physical injury when abuse is present and to elucidate all imaging findings that point to alternative diagnoses. Effective diagnostic imaging of child abuse rests on high-quality technology as well as a full appreciation of the clinical and pathologic alterations occurring in abused children. This statement is a revision of the previous policy published in 2000.

Imaging of the central nervous system in suspected or alleged nonaccidental injury, including the mimics

Because of the widely acknowledged controversy in nonaccidental injury, the radiologist involved in such cases must be thoroughly familiar with the imaging, clinical, surgical, pathological, biomechanical, and forensic literature from all perspectives and with the principles of evidence-based medicine. Children with suspected nonaccidental injury versus accidental injury must not only receive protective evaluation but also require a timely and complete clinical and imaging workup to evaluate pattern of injury and timing issues and to consider the mimics of abuse. All imaging findings must be correlated with clinical findings (including current and past medical record) and with laboratory and pathological findings (eg, surgical, autopsy). The medical and imaging evidence, particularly when there is only central nervous system injury, cannot reliably diagnose intentional injury. Only the child protection investigation may provide the basis for inflicted injury in the context of supportive medical, imaging, biomechanical, or pathological findings.

Classical osteogenesis imperfecta and allegations of nonaccidental injury

We report 12 patients with osteogenesis imperfecta initially diagnosed with nonaccidental injuries. As a result, formal hearings, care proceedings, and criminal proceedings ensued and seven of the children were removed from their parents. The features suggestive of osteogenesis imperfecta at the time of the initial investigation included a positive family history in six patients, scleral discoloration in nine, abnormally large anterior fontanels in four, excessive numbers of wormian bones in four, abnormal bone texture in two, and abnormal biochemical findings in three. There were discrepancies between the fractures and other clinical evidence of inflicted trauma. The seven patients removed from their homes eventually were returned. Five patients remained at home. Information was available on the subsequent history of the patients for an average of 4.8 years. Although seven patients have had additional fractures, there have been no additional allegations of nonaccidental injury. When investigating children with unexplained fractures, it is important to review carefully their clinical history, family history, physical examination findings, and radiographic findings. Misdiagnosing patients with nonaccidental injuries causes substantial harm to the family and particularly to the child.

Evaluating infants and young children with multiple fractures

Infants and toddlers with multiple unexplained fractures are often victims of inflicted injury. However, several medical conditions can also cause multiple fractures in children in this age group. In this report, the differential diagnosis of multiple fractures is presented, and diagnostic testing available to the clinician is discussed. The hypothetical entity "temporary brittle-bone disease" is examined also. Although frequently offered in court cases as a cause of multiple infant fractures, there is no evidence that this condition actually exists.

Hypothesis: fetal movement influences fetal and infant bone strength

Infants who present with multiple unexplained fractures in which there is no prior trauma, no radiographic evidence of metabolic bone disease, and no biochemical evidence of metabolic bone disease are almost always diagnosed as victims of child abuse, even though parents and caregivers deny wrongdoing. Such a diagnosis has far reaching implications for the infant and family. This article describes the clinical features of 65 such infants with multiple unexplained fractures in which the parents and caregivers deny wrongdoing and in which child abuse was diagnosed. These infants have the phenotype of temporary brittle bone disease that was described by Paterson. A striking observation in these young infants is the pregnancy history of decreased fetal movement. A hypothesis is suggested as an alternative explanation for the mechanism of these fractures in these infants--namely temporary brittle bone disease from fetal immobilization. This hypothesis states that fetal bone loading through fetal movement is essential for the formation of bones of normal strength. This hypothesis is an application of Frost's mechanostat/bone-loading model of bone physiology to the prenatal period of bone formation. This hypothesis explains many of the other observations about temporary brittle bone disease including the early onset of the fractures in the first several months of life, the lack of bruising, the lack of other internal organ injury, and the low risk profile of many of the parents for committing child abuse.

Femur fractures in infants and young children

Using an administrative database, we determined rates of femur fracture by year of age for children younger than 6 years and by month of age. The highest rate of femur fracture was in children younger than 1 year and in 2-year-olds; the greatest number of fractures occurred during the third month of life. While femur fractures in children are often due to accidental injury, the reasons for the peak in the first year and the subsequent decline are not clear.

The lesson of temporary brittle bone disease: all bones are not created equal

Temporary brittle bone disease (TBBD) is a recently described phenotype of multiple, unexplained fractures in the first year of life and predominantly in the first 6 months of life. There is usually no other injury such as bruising, subdural hematomas, retinal hemorrhages, or other internal organ injury. The susceptibility to fracture is transient, and there are no other radiographic or biochemical abnormalities noted in the standard evaluation that might suggest an underlying cause. The child abuse and pediatric radiology communities have, for the most part, been unwilling to accept this as a real condition, for they believe it is a ruse for child abuse. This review describes the experience of the author in evaluating infants with multiple unexplained fractures and the hypothesis that has emerged for explaining TBBD. The hypothesis is a prenatal application of the mechanostat/bone loading theory of bone formation and states that TBBD is caused by fetal immobilization which leads to fetal bone unloading and transient, relative osteopenia. Such susceptible infants can fracture with routine handling and present with a pattern of fractures that is similar to that which has been thought to be highly specific for child abuse. The review presents: (a) the evidence that indicates that normal fetal movement is important for normal fetal bone strength, (b) a critique of the radiologic approach in the diagnosis of child abuse in infants with multiple unexplained fractures, (c) observations that would indicate that child abuse is unlikely in infants with TBBD, and (d) new approaches to the infant with multiple unexplained fractures that would assist in accurate diagnosis.

Effect of cyclical intravenous pamidronate therapy in children with osteogenesis imperfecta. Open-label study in seven patients

OBJECTIVES

To evaluate the efficacy of pamidronate in protecting against fractures, increasing bone mineral density (BMD), and decreasing bone remodeling marker levels in children with osteogenesis imperFecta.

PATIENTS AND METHODS

Seven children (two girls and five boys; mean age, 8.5 years) were given cyclical intravenous pamidronate (Aredia) for 1 to 7 years, with a mean cycle duration of 6 months and a mean dose of 1.86 mg/kg/cycle. Four patients had type III and three type IV disease according to the Sillence classification scheme.

RESULTS

A trend toward a decrease in the fracture rate as compared to the pretreatment period was found, but the difference was not significant in this small sample (P = 0.09). Lumbar spine BMD showed a significant annual increase (+26.7%, P = 0.03) far greater than the expected mean annual increase related to growth. No significant decreases in bone remodeling markers were noted.

CONCLUSION

Pamidronate seems useful in the treatment of osteogenesis imperfecta in children, since it increases BMD and reduces the fracture rate, in keeping with the findings from the larger series studied by Glorieux. Pamidronate is a symptomatic, noncurative treatment that does not correct the genetic abnormalities responsible for the histological bone alterations.

Imaging of child abuse

Skeletal imaging plays a critical role in the diagnosis of abuse. High-detail radiographs of the entire skeleton, at times supplemented with nuclear imaging, CT, US, and MR imaging, elucidate the variety of findings with this entity. The radiologist's role includes careful analysis of clinical history, familiarity with typical osseous findings in abuse, and awareness of potential normal variants and pitfalls. An accurate diagnosis of abuse can then lead to appropriate measures to protect all family members at risk of serious injury.

Osteogenesis imperfecta: perspectives and opportunities

The last 2 years have seen additions proposed to the very limited armamentarium of treatments for osteogenesis imperfecta. These include the use of bisphosphonates to decrease bone resorption, growth hormone to augment growth and collagen production, and bone marrow transplantation to create chimeras at the level of the collagen production unit in bone. Although there are optimistic proponents for each strategy, the lack of well-controlled studies and the absence of clearly defined objectives for therapy hinder clear assessment.

Osteogenesis imperfecta: practical treatment guidelines

Osteogenesis imperfecta (OI), an inherited connective tissue disorder of remarkable clinical variability, is caused by a quantitative or qualitative defect in collagen synthesis and is characterised by bone fragility. The number of fractures and deformities, and the age at which they begin greatly influence the prognosis and the achievement of walking and autonomy. A multidisciplinary team approach is essential for diagnosis, for communication with patient and parents, and to tailor treatment needs to the severity of the disease and the age of the patient. Three types of treatment are available: nonsurgical management (physical therapy, rehabilitation, bracing and splinting), surgery (intramedullary rod positioning, spinal and basilar impression surgery), and drugs to increase the strength of bone and decrease the number of fractures. An aggressive rehabilitative approach is indicated to optimise functional ability and walking capacity; appropriately timed surgery to insert intramedullary rods provides improved function of extremities. Despite a high rate of complications, intramedullary telescopic roding has proven to be the most successful method for preventing and correcting fractures and deformities of long bones, improving walking capability and leading to successful rehabilitation of even severely affected patients. Surgery may be required in patients with progressive spinal deformity and in those with symptomatic basilar impression. Hearing function, dentinogenesis imperfecta, cardiac and respiratory function, and neurological changes must be monitored. The causal defect of the disease cannot be corrected with medical treatment and, currently, only symptomatic therapy is available. In recent years growth hormone (GH) and bisphosphonate agents have been used in OI therapy. GH is beneficial in patients with moderate forms of OI, showing a positive effect on bone turnover, bone mineral density and height velocity rate. Bisphosphonates have proved beneficial in children with severe OI, increasing bone mineral density and reducing the fracture rate and pain with no adverse effects reported. These data require confirmation in double-blind controlled studies; however, bisphosphonates have markedly improved morbidity in patients with OI. Future developments in genetic therapy may be directed towards either replacing cells carrying the mutant gene with normal cells or silencing the mutant allele using antisense suppression therapy, thus transforming a biochemically severe form of OI into a mild form.

Orofacial considerations for pediatric, adult, and elderly victims of abuse

Health care providers must take the time to educate themselves about domestic violence, its signs and symptoms, and the proper care of victims of child, spouse, or elder abuse. It is not enough to treat the immediate injuries without offering necessary and appropriate intervention on behalf of the victim. No one deserves to be beaten, sexually abused, or emotionally mistreated. If abuse is suspected, report it to the proper authorities. By focusing attention on this major health problem, physicians can provide a leadership role in using health care response to reduce the incidence of abuse and, ultimately, to save lives.

Diagnostic imaging of child abuse

The role of imaging in cases of child abuse is to identify the extent of physical injury when abuse occurs, as well as to elucidate all imaging findings that point to alternative diagnoses. Diagnostic imaging of child abuse is based on both advances in imaging technology, as well as a better understanding of the subject based on scientific data obtained during the past 10 years.(1-3) The initial recommendation was published in Pediatrics (1991;87:262-264).

Temporary brittle bone disease: a true entity?

Temporary brittle bone disease is a recently described phenotype of increased fracture susceptibility in the first year of life in which there are multiple unexplained fractures without evidence of other internal or external injury. Most child abuse experts do not accept the existence of temporary brittle bone disease and presume these cases are child abuse. The author reviewed 26 cases of infants with multiple unexplained fractures that fit the criteria of temporary brittle bone disease and studied nine of them with either computed tomography or radiographic bone density measurements. The results show a striking association between temporary brittle bone disease and decreased fetal movement, usually from intrauterine confinement, and low bone density measurements in eight of the nine infants. The association with decreased fetal movement and intrauterine confinement is in keeping with the mechanostat-mechanical load theory of bone formation. The author feels that temporary brittle bone disease is a real entity and that historical information related to decreased fetal movement or intrauterine confinement and the use of bone density measurements can be helpful in making this diagnosis.

Neurology and the skin

As knowledge of pathophysiology grows, so does the refinement of diagnoses. Sometimes increased knowledge permits consolidation and unification. Unfortunately, at our present level of understanding, it usually demands proliferation of diagnostic categories. As tedious as this diagnostic splintering may seem, such is the price currently exacted of both the investigator and the clinician who seek to optimise management. Increased diagnostic refinement often requires inquiry into matters outside the bounds of one's specialty. Most often we turn to the radiologist or to the laboratory to narrow the differential diagnosis generated from the history and neurological examination. As we have shown, a useful intermediate step is extension of the physical examination to organs such as the skin, which are not the traditional preserve of the neurologist. That any text could confer the sophistication required for expert dermatological diagnosis is an unrealistic expectation. However, we hope that this review will encourage careful examination of the skin, hair, and nails by the neurological practitioner, with consideration of referral to a dermatologist when greater expertise is required.