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Failure to appreciate key anatomic features and suboptimal sonographic technique lead to incorrect assessment of the key elements of developmental dysplasia of the hip: position, stability, and morphology. In this article, we address common errors, identify sonographic features critical for accurate image interpretation, and address measurement variability.

Background/Purpose Pediatric colonic volvulus is both rare and underreported. Existing literature consists only of case reports and small series. We present an analysis of cases (n = 11) over 15 years at a single institution, focusing on workup and diagnosis. Methods This was an institutional review board approved single-institution retrospective chart review of 11 cases of large bowel volvulus occurring over 15 years (2000–2015). Results In our series, the most common presenting symptoms were abdominal pain and distention. Afflicted patients often had prior abdominal surgery, a neurodevelopmental disorder or chronic constipation. Of the imaging modalities utilized in the 11 patients studied, colonic volvulus was correctly diagnosed by barium enema in 100% of both cases, CT in 55.6% of cases and by plain radiography of the abdomen in only 22.2%of cases. Colonic volvulus was confirmed by laparotomy in all cases. The cecum (n = 5) was the most often affected colonic segment, followed by the sigmoid (n = 3). Operative treatment mainly consisted of resection (63.6%) and ostomy creation (36.4%). Colopexy was performed in 18.2% of cases. Conclusions Plain abdominal radiography may be performed as an initial diagnostic study, however, it should be followed CT or air or contrast enema in children where there is high clinical suspicion and who do not have indications for immediate laparotomy. CT may be the most specific and useful test in diagnosis of colonic volvulus and has the added advantage of detection of complications including bowel ischemia. We demonstrate a range of diagnostic and therapeutic modalities for pediatric colonic volvulus. This underscores the need for further study to draft standard best practices for this life-threatening condition. Level of Evidence Prognosis Study: Level IV. Study of a Diagnostic Test: Level III.

Integration was implemented of previously independently practicing pediatric radiology services across a pediatric health care system with sites 1,000 miles apart.The purpose of this manuscript is to describe the process utilized to integrate imaging services across our enterprise and to study the direct effects on report turnaround time and other parameters.Parameters were evaluated both the year before integration as well as the 2 years following integration and compared for improvement. Parameters studied included report turnaround time, academic productivity (as measured by peer review publications per year), and degree of sub-subspecialization within pediatric radiology (as measured by the percentage of neuroimaging CT and MRI studies read by pediatric neuroradiologists).Comparing pre- to post-integration measures, the median report turnaround time decreased from 2.3 h to 1.1 h (52.1% improvement), the percentage of neuroimaging studies read by neuroimaging faculty increased from 15.0% to 86.6% (477% improvement), and peer review publication by calendar year increased from 3 to 30 (1,000% improvement). Other benefits included increased hours of in-house coverage and execution on multiple quality improvement efforts.A pediatric health care system successfully integrated radiology services across multiple previously non-integrated locations into one functional group. This integration was associated with a positive effect on multiple parameters.

BACKGROUND In the treatment of early onset scoliosis (EOS), there has been a trend to use magnetically controlled growing rods (MCGR) in order to reduce the number of surgeries. To confirm the amount of lengthening, spine radiographs were required. Recently, ultrasound (US) has been added to monitor lengthening of MCGR to avoid radiation exposure. Our aim was to determine whether US is as accurate as plain radiography (x-ray) in determining the amount of length achieved at individual MCGR lengthening episodes. METHODS Retrospective study; inclusion criteria: EOS cases with dual MCGR with minimum 12 months follow-up. Intended lengthening IL (mm), lengthening on US (mm) and x-ray (mm) were documented from medical records for both right and left rods. Primary (no surgery before MCGR) and conversion (other types of instrumentation were replaced with MCGR) cases were reviewed separately. P-values determined with analysis of variance. RESULTS Sixteen cases with 100 lengthening episodes met the inclusion criteria. Eleven were primary MCGR cases with 67 episodes. Mean follow-up was 19±5 months. Significant differences were found between IL (3.4±1 mm), US (2.7±1.9 mm), and x-ray (4.1±2.2 mm) (P

Background: Skeletal dysplasias may be associated with cervical spinal instability or stenosis. Cervical spine flexion-extension plain radiographs in children with skeletal dysplasia are difficult to interpret. The purpose of this study was to review the indications, efficacy, and safety of performing flexion-extension magnetic resonance imaging (MRI) under sedation/anesthesia in these children. Methods: Retrospective, Institutional Review Board–approved review of 31 children with skeletal dysplasia who underwent 38 cervical spine flexion-extension MRI studies under sedation/anesthesia. Indications included abnormal neurological examination, suspected instability, stenosis, or inconclusive findings on flexion-extension radiographs. Studies were performed by the radiology technologist as directed by the radiologist with an anesthesiologist present. MRI was evaluated for odontoid hypoplasia, os odontoideum, cerebrospinal fluid effacement, cord compression, spinal cord changes, cervical canal narrowing in the neutral, flexion, and extension positions. Neurological examinations were recorded before and after MRI to assess safety. Results: The average age at MRI was 3 years, 2 months. In 6 patients whose plain radiographs showed C1-C2 or subaxial instability, flexion-extension MRI showed no cord compression. Nine patients with inconclusive plain radiographs had abnormal MRI findings. An os odontoideum not seen on plain radiographs was diagnosed in 3 patients on flexion-extension MRI. On the basis of the MRI findings, 14 patients underwent surgery, 9/14 had increased cord compression in flexion or extension compared with neutral, and observation was continued in 17 others. Patients who underwent surgery had significant cord compression on MRI. There were no significant changes in the neurological examinations after MRI. Conclusions: Cervical spine flexion-extension MRI under sedation/anesthesia in children with skeletal dysplasia is safe under adequate supervision and is necessary to guide accurate medical and surgical decision making. Flexion-extension MRI is useful for identifying dynamic changes in canal diameter resulting in cord compression not seen on plain radiographs, and it is also useful for identifying patients with suspected plain film instability who may not have stenosis or cord compression on MRI. Study Design: Level IV—retrospective case series.

BACKGROUND In reduction of hip displacement in developmental dysplasia, concentric placement of the femoral head within the acetabulum is key. Magnetic resonance imaging (MRI) is an effective modality to assess the adequacy of the reduction, but sedation may be required due to the length of the examination. MRI is also more expensive than other imaging modalities. Our goal was to provide an MRI protocol that does not require sedation and can be performed in

Object The CT modality plays a central role in the diagnosis of cervical spine fractures. In childhood, radiolucent synchondroses between ossification centers can resemble fractures, and they can be the sites of fractures as well. Recognition of cervical spine fractures in children requires familiarity with normal developmental anatomy and common variants as they appear on CT scans. Methods A convenience sample of 932 CT scans of the cervical spine accessible on the picture archiving and communications system (known as PACS) at a single children's hospital was examined. Scans were excluded from further analysis if they did not include the atlantoaxial region or were otherwise technically unsatisfactory; if the patient carried the diagnosis of a skeletal dysplasia; or if there were developmental lesions noted at other levels of the spine. No more than 1 scan per patient was analyzed. Synchondroses were graded as radiolucent, not totally radiolucent but still visible, or no longer visible. Their locations and symmetries were noted. The presence or absence of the tubercles of the transverse ligament was noted as well. Results After exclusions, 841 studies of the atlas and 835 studies of the axis were analyzed. The 3 common ossification centers of the atlas arose in the paired neural arches and the anterior arch, but in as many as 20% of cases the anterior arch developed from paired symmetrical ossification centers. The 5 common ossification centers of the axis arose in the paired neural arches, in the basal center, in the dentate center (from which most of the dentate process develops), and in the very apex of the dentate process. The appearance of each synchondrosis was noted at sequential ages. The tubercles for the transverse ligament generally did not appear until the ossification of the synchondroses of the atlas was far advanced. Anomalies of the atlas included anterior and posterior spina bifida, absence of sectors of the posterior arch, and anomalous ossification centers and synchondroses. Anomalies of the axis were much less common. What appeared possibly to be chronic, incompletely healed fractures of the atlas were discovered on review for this analysis in 6 cases. No fractures of the axis were discovered. Conclusions There is substantial variation in the time course and pattern of development of the atlas, and anomalies are common. Some fractures of the atlas may escape recognition without manifest sequelae. Variation in the time course of the development of the axis is notable as well, but anomalies seem much less common.

In the nonambulatory cerebral palsy (CP) population with a prior history of fracture, the use of pamidronate is not always effective in preventing further fractures.To test the hypothesis that when fractures occur after cyclic pamidronate, they will be at the proximal or distal end of a pamidronate band.Retrospective review of our CP patient database revealed 53 children who had received one or more complete courses of pamidronate therapy (five cycles over 12 months). Medical records were screened to identify children who had sustained a fracture or fractures after completing treatment.Of 53 patients treated with pamidronate, only 14 sustained fractures after treatment. Radiographs were available for 11 patients, showing 19 fractures. Sixty-three percent of these fractures were located at a junction with pamidronate bands but not within the bands.We propose stress risers as the mechanism for fractures that have occurred where bone mineral density abruptly changes as a result of cyclic administration of pamidronate. We show a theoretical example of how alternative dosing might reduce the ratio and therefore decrease the chance of formation of a stress riser.

BACKGROUND: The purpose of this study is to evaluate the efficacy of the Pavlik harness treatment in patients with bilaterally dislocated hips, and to compare them with cases with unilaterally dislocated hips. METHODS: Twenty-nine patients (58 hips) were identified who presented with bilateral dislocated hips with no earlier treatment and received dynamic ultrasound examination. The comparison group consisted of 38 patients (38 hips) with unilateral hip dislocation treated with the same protocol. Successful treatment was defined as relocation/reduction of the hips within 3 weeks of Pavlik harness application. RESULTS: Seventeen of 29 patients (59%) in the bilateral group (7 bilateral, 10 unilateral) and 22 of 38 patients (58%) in the unilateral group failed the harness treatment. There was no difference in the duration of harness wear for successful patients regardless of presentation. CONCLUSIONS: Patients presenting with bilaterally dislocated hips treated with the Pavlik harness are at no greater risk for failure than patients presenting with unilateral hip dislocation. LEVEL OF EVIDENCE: Level 3.

Lateral growth disturbance of the proximal femoral physis after treatment of developmental dysplasia of the hip, also known as type 2 avascular necrosis, has been described in a 2-dimensional (2D) plane with standard radiographs. It is not well described in the 3-dimensional plane using 3D computed tomography (CT) scan. The purpose of this study was to define the anatomy of the proximal femur after the lateral growth disturbance of the proximal femoral physis with 3D CT scans.Ten patients (11 hips) with lateral growth disturbance of the proximal femoral physis after treatment for developmental dysplasia of the hip (9 hips) and extracorporeal membrane oxygenation (2 hips), were studied with 2D and 3D CT methods. CT was done at an average age of 12.5 years (range, 9.8 to 16.69).In addition to the typical valgus configuration in the coronal plane, increased antetorsion of the femur (10 of 11 hips) and increased anteversion of the femoral head (8 of 11 hips) were a common finding seen in the transverse plane. In 6 of 7 hips for which the CT scan was performed before the closure of the capital femoral epiphysis, the physeal bridge was seen to be located in the anterolateral (5 hips) or posterolateral (1 hip) area of the proximal femoral physis. The version of the femoral head was correlated to the location of the physeal bridge. Acetabular dysplasia was seen in 4 hips. In the 3D reconstruction view, flexion deformity of the femoral head was seen in 6 hips and lack of coverage at the anterolateral portion of the femoral head was observed in 6 hips.The treating surgeon should be aware of the often marked antetorsion and also anteversion of the femoral head and neck associated with lateral growth disturbance of the proximal femoral physis. This knowledge allows surgical planning to correct rotational and sagittal plane correction of the proximal femur, which will allow normalizing hip mechanics. Acetabular side correction also may be needed if acetabular dysplasia is present.Level III, diagnostic study.

The chapter begins with a section on the normal development of the pelvis, acetabulum, and femoral neck, head, and epiphysis. Discussion of congenital and developmental abnormalities follows. Proximal focal femoral deficiency is described first. This is followed by a discussion of both intrauterine hip dislocation and a lengthy discussion of developmental dysplasia of the hip (DDH). Within this section, many different imaging techniques are broken down, the treatment of DDH by osteotomies is discussed, and postoperative complications as well as differential diagnosis are explained. Sections on coxa vara and acetabular protrusion follow. Femoral head dysplasia is broken down into both localized and generalized disorders: microepiphyseal dysplasia, Meyer dysplasia, osteochondritis dissecans-like femoral head dysplasia, multiple epiphyseal dysplasia, and epiphyseal dysgenesis in hypothyroidism.

Background: Increasing numbers of children are being treated with the bisphosphonate pamidronate for low bone mineral density, particularly children with increased risk of fractures caused by bone disorders or low/non-weight bearing. Objective: To determine the effect of intravenous pamidronate on the bone mineral density of children with osteogenesis imperfecta and spastic quadriplegic cerebral palsy. Materials and methods: Charts of 38 children with osteogenesis imperfecta (n=20) and spastic quadriplegic cerebral palsy (n=18) treated with pamidronate were retrospectively reviewed. Patients were selected for treatment because of prior fracture and/or abnormally low bone mineral density. All received intravenous pamidronate at two-month to eight-month intervals and were periodically examined using dual energy X-ray absorptiometry. Results: All patients had abnormally low bone mineral density prior to treatment. Lumbar spine bone mineral density and z-scores showed serial improvement in 31 of 32 patients. Spine bone mineral density increased 78±38.1% in OI and 47.4±39.0% in children with cerebral palsy. The area of greatest lateral distal femur bone mineral density improvement was in the metaphysis adjacent to the growth plate, with a 96±87.8% improvement in the osteogenesis imperfecta group and 65.7±55.2% improvement in the cerebral palsy group. Increases in bone mineral density exceeded that expected for age-specific growth. This was demonstrated by improvement in both spine and femur z-scores for both groups. No children with spastic quadriplegic cerebral palsy experienced fractures after the first week of treatment, whereas patients with osteogenesis imperfecta continued to have fractures but at a decreased rate. Conclusions: Intravenous pamidronate given at 3- to 4-month intervals proved to be effective in increasing bone mineral density in patients with osteogenesis imperfecta and spastic quadriplegic cerebral palsy. The greatest gains in bone mineral density were observed in the children with osteogenesis imperfecta, but they did continue to fracture, albeit at a decreased rate. Children with cerebral palsy gained bone mineral density and did not continue to fracture.

In the infant, shoulder injury due to birth trauma and infection in joint and bone may be difficult to detect radiographically. Shoulder ultrasound provides a dynamic, noninvasive method of evaluation.To develop a technique to evaluate the infant shoulder and to successfully demonstrate pathology.Using a multiplanar, dynamic technique, 24 normal and 12 symptomatic infants (age range, 3 days to 9 months) were examined (49 shoulders).Sonographic findings were normal in 41 shoulders and abnormal in 8 shoulders. Abnormalities included subluxation, fracture, abnormal cartilage, soft-tissue mass, and inflammatory collections, including effusion.Ultrasound can be used successfully to evaluate the infant shoulder for instability, fracture, and infection.

One of the first successful applications of ultrasound to the musculoskeletal system was in evaluation of the infant hip. Sonography was particularly appropriate because it could successfully image the cartilage, which forms the majority of the femoral head and acetabulum in the first 6 months of life and is not visible on plain radiographs. Success with infant hip sonography fostered use of the technique in older children where presentation with pain or limp and a normal radiograph raises the question of hip joint pathology. In this discussion of sonography of the pediatric hip, we focus on diagnostic issues for the sonographer when examining the infant hip for development dysplasia, congenital abnormalities, and other conditions, such as inflammatory disease and trauma. In an older child with a painful hip, the differential diagnosis includes a variety of conditions in which there is a normal radiograph or nonspecific radiographic findings early in the course of the disease (see following) Conditions of Infancy Developmental dysplasia of the hip Proximal femoral focal deficiency Congenital coxa vara/skeletal dysplasia Congenital myopathy Septic arthritis/osteomyelitis Painful Hip Transient (toxic) synovitis Traumatic synovitis Inflammatory arthritis (e.g., juvenile chronic arthritis, Lyme disease) Septic arthritis/osteomyelitis Legg-Calve-Perthes disease Slipped capital femoral epiphysis Nonaccidental injury Neoplasm (e.g., osteoid osteoma) As with any sonographic study, the experience of the individual performing the examination is a critical element for accuracy of results. It is our intent to emphasize pitfalls that occur both in the performance of pediatric hip sonography and in the interpretation of the sonographic findings.

Biplanar digital slot-scanning allows for relatively low-dose orthopedic imaging, an advantage in imaging children given the growing concerns regarding radiosensitivity. We have used this system for approximately 1 year for orthopedic imaging of the spine and lower extremities. We have noted advantages of using the digital slot-scanning system when compared with computed radiographic and standard digital radiographic imaging systems, but we also found unexpected but common imaging artifacts that are the direct result of the imaging method and that have not been reported. This pictorial essay serves to familiarize radiologists with the advantages of the digital slot-scanning system as well as imaging artifacts common with this new technology.

Background The purpose of this study was to evaluate the efficacy of Pavlik harness treatment in patients with bilaterally dislocated Graf type IV hips and compare them to cases with unilaterally dislocated hips. Methods Twenty-one patients (42 hips) who presented with bilaterally dislocated hips with no prior treatment were studied. The comparison group consisted of 33 patients (33 hips) with unilateral hip dislocation treated with the same protocol. Successful treatment was defined as relocation of the hips within 3 weeks of Pavlik harness application. Results Twelve of 21 patients (57%) in the bilateral group (6 failed bilaterally, 6 unilaterally) and 18/33 patients (54.5%) in the unilateral group failed harness treatment. Conclusions The use of the Pavlik harness in dislocated hips is associated with a high failure rate. Patients presenting with bilaterally dislocated hips however, are at no greater risk for failure than patients presenting with unilateral hip dislocation. Level of evidence Level III.

As childhood obesity rates rise, laparoscopic adjustable gastric banding (LAGB) is being investigated as a bariatric surgical option in adolescents. To examine pre- and postoperative imaging in adolescents undergoing LAGB, describe the most common abnormal preoperative imaging findings, and illustrate the typical appearance and variants on postoperative upper-gastrointestinal (UGI) examinations. A retrospective chart review was performed of all adolescents from 2008 to 2010 undergoing LAGB at a single tertiary-care pediatric hospital. The picture archiving and communication system was queried for all imaging obtained before and after surgery. Postoperative UGI studies were analyzed for common patterns. Twenty-seven obese adolescents who underwent LAGB were identified. Twenty-five had preoperative imaging, most commonly a UGI study (81.5%). Eight UGI studies were abnormal but did not impact surgery. Preoperative chest and neck radiographs were also common. Intraoperative imaging was rare. Seventy-three postoperative UGI studies were performed on 22 children (range, 2–12 studies). A common postoperative imaging pattern was observed in 19/22 (86%) children. No complications were observed. The most common pre- and postoperative imaging studies in adolescents undergoing LAGB are UGI studies. Pediatric radiologists should be familiar with the imaging of LAGB as this procedure becomes increasingly common.

The CT modality plays a central role in the diagnosis of cervical spine fractures. In childhood, radiolucent synchondroses between ossification centers can resemble fractures, and they can be the sites of fractures as well. Recognition of cervical spine fractures in children requires familiarity with normal developmental anatomy and common variants as they appear on CT scans.A convenience sample of 932 CT scans of the cervical spine accessible on the picture archiving and communications system (known as PACS) at a single children's hospital was examined. Scans were excluded from further analysis if they did not include the atlantoaxial region or were otherwise technically unsatisfactory; if the patient carried the diagnosis of a skeletal dysplasia; or if there were developmental lesions noted at other levels of the spine. No more than 1 scan per patient was analyzed. Synchondroses were graded as radiolucent, not totally radiolucent but still visible, or no longer visible. Their locations and symmetries were noted. The presence or absence of the tubercles of the transverse ligament was noted as well.After exclusions, 841 studies of the atlas and 835 studies of the axis were analyzed. The 3 common ossification centers of the atlas arose in the paired neural arches and the anterior arch, but in as many as 20% of cases the anterior arch developed from paired symmetrical ossification centers. The 5 common ossification centers of the axis arose in the paired neural arches, in the basal center, in the dentate center (from which most of the dentate process develops), and in the very apex of the dentate process. The appearance of each synchondrosis was noted at sequential ages. The tubercles for the transverse ligament generally did not appear until the ossification of the synchondroses of the atlas was far advanced. Anomalies of the atlas included anterior and posterior spina bifida, absence of sectors of the posterior arch, and anomalous ossification centers and synchondroses. Anomalies of the axis were much less common. What appeared possibly to be chronic, incompletely healed fractures of the atlas were discovered on review for this analysis in 6 cases. No fractures of the axis were discovered.There is substantial variation in the time course and pattern of development of the atlas, and anomalies are common. Some fractures of the atlas may escape recognition without manifest sequelae. Variation in the time course of the development of the axis is notable as well, but anomalies seem much less common.

Persistent low-back pain in children that is not associated with trauma and is not relieved by two to three weeks of rest, modification of activity, or nonsteroidal anti-inflammatory medication is uncommon. If a child has persistent, unremitting low-back pain, a serious underlying pathological cause should be suspected and appropriately investigated and a thorough evaluation, including the recording of a medical history, clinical examination, and radiography, should be performed. The purpose of the current report is to describe our findings in two patients, who were eight and thirteen years of age when they presented with pain in the low lumbar area secondary to a lesion in the sacrum. These two unusual cases highlight the importance of a careful clinical examination and imaging of the sacrum in the evaluation of low-back pain in children. Case 1. An eight-year-old girl presented with low-back pain that had had an acute onset. She was seen in an emergency room, where radiographs of the lumbar spine were interpreted as normal. The pain continued for a week, and she was then seen at our institution. She described low-back pain that radiated to the groin and the anterior aspects of the thighs. She reported no tingling or numbness in the lower extremities and no bowel or bladder symptoms. Walking, sneezing, defecation, and laughing worsened the pain. Physical examination revealed no gross motor or reflex changes, but there was decreased pin-prick sensation on the sole of the left foot. The radiographs that had been made at the other institution were not available for …

Purpose: Amyoplasia (type 1), characterized by quadrimelic limb involvement, is one of the most common types of arthrogryposis. In children with hyperextension or extension contracture of the knee, subluxation or dislocation of the knee joint with an associated subluxation or dislocation of the patella is frequently seen. Patellar malpositioning may be secondary to congenital hypoplasia of the patellar groove of the femur and/or dysplasia of the patellofemoral joint. A contracted quadriceps tendon and illiotibial band, as seen in extension contractures of the knee in arthrogryposis, may also contribute to patella alta and lateral subluxation of the patella. The aim of our study is to determine the position of the patella in children with quadrimelic arthrogryposis and knee extension contracture. Methods: The inclusion criteria for this study were as follows: patients diagnosed with arthrogryposis multiplex congenita group 1, a knee extension contracture present from birth, follow-up from birth or early childhood, at least yearly physical examinations, and a knee ultrasonography or magnetic resonance imaging study performed. Patellar position was determined, and the cartilaginous femoral sulcus angle, as well as the osseous femoral sulcus angle, was measured. Results: Clinically, none of patella in any of the patients could be palpated before surgery. The patella was displaced superiorly and laterally in 16/16 knees as seen on ultrasonography. Magnetic resonance imaging also showed the patella to be displaced superior and laterally. Conclusions: All patients in our series with extension contracture of the knee and type 1 arthrogryposis had a patella that was superior and lateral to the patellar groove. We found that quadricepsplasty and relocation of the patella improved knee flexion. All patients regained active knee extension in 6 months postsurgery. Level of Evidence: Level III-diagnostic.

Although the use of ultrasound in the diagnosis and early treatment of developmental dysplasia of the hip (DDH) has reduced the number of patients diagnosed late and decreased the number of operative procedures, surgical treatment is still needed in some patients. Late cases continue to occur as a result of missing the screening examination, being normal at initial screening and missing followup. Dysplasia may persist despite appropriate nonoperative or operative treatment. Many of these patients subsequently undergo closed or open reduction and femoral or acetabular reconstruction. Ultrasound of the hips is generally used up to 6 or 8 months of age, during which time the hips are largely cartilaginous, and radiographs after that time when bony development is more complete. Options to supplement ultrasound and radiography include arthrography, computed tomography, and magnetic resonance imaging. Several advances have been made in the imaging of DDH and its complications including acetabular labral pathology and of femoroacetabular impingement (FAI). We review imaging techniques other than ultrasound used in the management of DDH.Level V, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Morquio-Brailsford syndrome (MS) is an autosomal recessive lysosomal storage disorder, a mucopolysaccharidosis, characterized by abnormal metabolism of glycosaminoglycans. Major treatable concerns in patients with MS involve C1 to C2 instability, genu valgum, and hip subluxation. Untreated hip subluxation has been shown to predispose to early onset of arthritis of the hip. Early appropriate pelvic osteotomies may restore (improve) load transmission and retard the onset of arthritis. Computed tomographic (CT) measurements can help determine the site and severity of acetabular deficiency, aiding in selection of the appropriate acetabular procedure. Acetabular morphology in MS has not been described in the literature. The purpose of this study was to evaluate morphology (shape) of the acetabulum in MS using two-dimensional (2-D) CT scans.To assess the acetabular roof, the acetabular index was measured on anteroposterior radiographs of the pelvis. Various CT measures were used to assess the acetabular anatomy in the axial plane.The average acetabular index on the anteroposterior radiographs of the pelvis was 33 degrees (average age-matched difference from normal, 12 degrees). Two-dimensional CT (axial cuts) showed that the average acetabular anteversion angle was close to normal, measuring 10.9 degrees. The average anterior acetabular index was 58.8 degrees (average age-matched difference from normal, 10.6 degrees), and posterior acetabular index was 53.8 degrees (average age-matched difference from normal, 3.8 degrees). Calculated axial acetabular index ranged from 90 to 133 degrees (mean, 112.6 degrees; average difference from normal, 14.5 degrees).Two-dimensional CT of the hip in patients with MS demonstrated a severe dysplasia of the anterior acetabular wall and the roof of the acetabulum, although the acetabular version was normal. Treatment of hip dysplasia in MS should focus on increasing the overall depth of the acetabulum to better contain the femoral head. Two-dimensional CT is recommended before bony acetabular procedures to assess the degree of acetabular deficiencies.Computed tomography of the acetabulum is helpful in preoperative decision making and planning before an acetabular procedure in patients with Morquio-Brailsford syndrome.

Real-time sonography is gaining wide acceptance as the method of choice for imaging the infant hip. The dynamic technique of hip sonography incorporates motion and stress maneuvers that are based on accepted clinical examination techniques. The multiview dynamic assessment emphasizes hip position and stability, but includes assessment of acetabular development. It has been found to be effective in the initial detection of infant hip abnormalities and in monitoring treatment.

Background: Patients with congenital osseous anomalies of the spine are known to have a high prevalence of abnormalities in the renal system and of the spinal cord. Today, the screening tools of choice to detect these abnormalities include ultrasonography of the kidneys and collecting system and magnetic resonance imaging of the spine. A single screening tool that can identify both renal and intraspinal anomalies would be ideal. Methods: Imaging studies of all patients with a congenital osseous anomaly of the spine seen at our institution during a ten-year period were retrospectively reviewed. Only patients who had had both a sonogram of the renal system and a magnetic resonance imaging study of the entire spine were included in the investigation. All studies were reviewed blindly by a pediatric radiologist for this study. Results: One hundred and fifty-three patients met the criteria for inclusion in the study. Forty-one patients (27%) had a total of forty-seven renal abnormalities noted on both the sonogram and the magnetic resonance imaging scan. In no instance was a renal anomaly seen on one study and not on the other. Conclusions: When properly performed, screening magnetic resonance imaging scans of the spine can show renal abnormalities, thus obviating the need for a separate screening renal ultrasound study. Level of Evidence: Diagnostic Level IV. See Instructions to Authors for a complete description of levels of evidence.

High-signal T2-weighted bone marrow changes can be found in both bone marrow edema and hematopoietic marrow and are often seen on pediatric MR images of the feet and ankle.To evaluate whether high-signal T2 changes of the bone marrow seen on pediatric MRI of feet and ankles represent residual hematopoietic marrow.A total of 402 bones in 41 pediatric MRI studies of feet and ankles (34 children, 1-18 years) were reviewed by two observers who were blinded to the patients' ages. The studies were reviewed for the presence of high-signal changes of the bone marrow on sagittal fluid-sensitive images. The frequency and location of these foci were correlated with the patients' ages.High-signal T2 changes of the bone marrow were seen in 45/402 bones (11%) and in 24/41 patients younger than 16 years (59%). The changes were most commonly located in the calcaneus (54%), followed by the talus (35%) and navicular bone (35%), invariably at the endosteal surface. In 16 ankles, such foci were seen in the feet but not in the distal tibia/fibula. Symmetric presence (two ankles) or absence (four ankles) of high-signal marrow were seen in six of seven patients with bilateral ankles.High-signal T2 changes of the bone marrow in pediatric feet and ankle MRIs have a symmetric, fairly consistent pattern and disappear after the age of 15 years. We believe that these high-signal areas are normal and represent residual hematopoietic marrow.

Lower-extremity bowing is common in infants and children and can result from a variety of conditions. At radiography, developmental bowing shows varus angulation centered at the knee, "metaphyseal beaking," thickening of the medial tibial cortices, and tilted ankle joints. Tibia vara (Blount disease) demonstrates genu varum and depression of the proximal tibia medially. Congenital bowing manifests as posteromedial bowing with cortical thickening along the concavity of the curvature and, in some cases, diaphyseal broadening. In rickets, radiographic changes occur primarily at sites of rapid growth and are predominantly metaphyseal, with widening of the zone of provisional calcification. Achondroplasia is characterized by shortening and thickening of the long bones with metaphyseal flaring and cupping. In neurofibromatosis, there may be anterolateral bowing of the tibia, and there is often focal narrowing and intramedullary sclerosis or cystic change at the apex of the angulation. The tibia is typically involved at the junction of the middle and distal thirds. Osteogenesis imperfecta demonstrates bowing from softening due to osteoporosis and multiple fractures and typically involves the entire skeleton. In camptomelic dysplasia, lower-extremity bowing is associated with a short trunk, short limbs, and deficiencies in pelvic bone development. Recognition of these pathologic conditions is important for differentiating those that will resolve spontaneously from those that require surgery or other treatment.

Pediatric patients are being treated with bisphosphonates for low bone mineral density. Skeletal radiographic findings have been described with bisphosphonates given orally and intravenously. To determine and describe the radiographic findings of cyclic intravenous bisphosphonate therapy in the growing skeleton. Retrospective review of radiographs of 32 patients with osteogenesis imperfecta or cerebral palsy treated with intravenous bisphosphonates on a quarterly schedule. Principal observations were metaphyseal bands and increased bone mineral density. The bands varied in spacing according to the age of the patient, rate of growth, and the location of the metaphysis. Fractures continued to be seen in patients with osteogenesis imperfecta. Cyclic bisphosphonate therapy results in distinctive radiographic findings in the growing skeleton.

We describe twin brothers and father with autosomal dominant spondylo-epiphyseal dysplasia (SED) tarda. The proband presented at 17 years with nystagmus and esotropia due to a severe Chiari malformation. A milder, asymptomatic Chiari I malformation was seen in his brother and tonsillar ectopia in his father. Although these malformations have not been described in patients with SED, they are relatively common in other bony abnormalities, particularly those involving the cranio-cervical junction. The concordance of the Chiari malformations or tonsillar ectopia in all three family members with SED suggests that this association is not coincidental. It seems possible that the downward displacement of the cerebellum occurs secondary to primary osseous abnormality, rather than due to a primary disturbance of embryological development. The lack of additional brain malformations in our patients is consistent with this theory.

We examined 45 infants with nondevelopmental dysplasia of the hip (non-DDH), including congenital deficiency of the femur (CDF) (20 infants), neuromuscular syndrome (five infants), skeletal dysplasia (15 infants), and infection (five infants), and present the sonographic findings. Dysmorphic proximal femora, coxa vara, and abnormal echogenicity of the soft tissue and cartilage are features which differentiate patients with non-DDH from those with typical DDH.

A case of hypervitaminosis A (HVA) as a complication of therapy for stage-IV neuroblastoma is presented. The patient was randomized to a trial of 13-cis -retinoic acid (a vitamin A-related compound) after completing routine chemotherapy. This acid was given as a means of maturing potential minimal residual disease. A routine follow-up bone scan revealed areas of increased activity, initially along the midshaft of the right ulna and subsequently bilaterally, which were ultimately found to be due to HVA. Hypervitaminosis A has not been previously reported in this setting, and awareness of the condition is important in centers where this treatment is contemplated.

Intranasal midazolam offers an attractive alternative for use as a sedative agent for medical imaging studies in children. Its convenient administration and rapid onset are significant advantages over intravenous and oral agents. Because of its short duration, it is effective only for short procedures and as an adjunct to other sedative agents. When younger children present with such requirements, a dose of 0.2 mg/kg has been safe and effective in our experience. We advocate its use with adherence to guidelines for sedation published by the American Academy of Pediatrics.

Sonography of the infant hip has gained wide acceptance in the decade since its introduction. The two principle techniques of Graf and Harcke have been combined with the proposal of a Dynamic Standard Minimum Examination. Whereas sonography is used increasingly to manage developmental dislocation and/or displasia of the hip, there is no agreement on the use of sonography for universal newborn screening. This article describes in detail the Dynamic Standard Minimum Sonographic Examination of the infant hip. In addition, this article reviews the classification and management of infant hip disorders.

Dynamic hip sonography was performed in 15 infants (19 hips) with congenital abnormalities of the hip. Radiographs of all 15 patients revealed congenital deficiency of the femur (CDF), type I-V, using the classification described by Kalamchi et al. Sonography was accurate in delineating hip position and morphology in all cases, and was a helpful adjunct to radiography in defining the hip joints in 13 hips with type II and type III deficiency of the femur.

In the evaluation of tibial hemimelia, it is important to establish the presence or absence of the cartilaginous tibial anlage. When present, sonography effectively identifies and characterizes the tibial cartilage anlage and determines the presence and integrity of the patellar tendon.

Bony anomalies of the thorax may occur as isolated problems, but are also seen in conjunction with other skeletal or organ anomalies. Among the most common thoracic osseous anomalies are pectus excavatum, pectus carinatum, sternal ossification abnormalities, and deformity of the spine, ribs, clavicle, or scapula. The presence of any of these anomalies should increase the index of suspicion for associated problems. Review of the history and physical examination, combined with a knowledge of commonly associated malformations, will allow appropriate additional imaging studies to be selected. Many osseous anomalies of the thorax do not require treatment; in some instances, however, problems with function, progressive deformity, or cosmetic considerations may necessitate surgical treatment.

Fifty infants undergoing treatment in the Pavlik harness for congenital hip dysplasia (CDH) were serially evaluated with ultrasound. Comparison with clinical and radiographic examinations showed sonography to be 100% sensitive and highly specific. Discrepancies between the studies are attributed to the greater sensitivity of the technique compared with the physical examination and/or radiographs. Using this method, it is possible to significantly reduce radiation exposure to the infant being treated for CDH.