Characterization of Hip Morphology in Children With Mucopolysaccharidosis Types I and II.

BACKGROUND: The purpose of this study is to describe the natural history of hip morphology in patients with mucopolysaccharidoses (MPS) I and MPS II. METHODOLOGY: This is a retrospective radiographic analysis of 88 hips in 44 children with MPS I and II. Radiographs were examined to determine hip migration, femoral head sphericity, and acetabular dysplasia at different ages throughout childhood. In individual hips, change in morphology and rate of change were analyzed. RESULTS: There was a high rate of hip migration and femoral head dysplasia in both MPS I and MPS II. Progressive migration was seen in three quarters of hips and progressive femoral head deformity in over half of hips. Acetabular dysplasia was variable, ranging from normal to severely dysplastic, but did not change with time. Overall, hips were more dysplastic in MPS I than MPS II. CONCLUSIONS: Hip morphology is variable in MPS I and MPS II ranging from almost normal to severely dysplastic. Some hips do not deteriorate with time and thus surgical intervention may not be necessary in all cases. Deterioration is slow allowing time to plan a holistic approach to treatment. LEVEL OF EVIDENCE: Level IV-case series.

Radiologic findings of Patterson-Lowry rhizomelic dysplasia in two sisters.

We report two sisters who have a rare skeletal abnormality termed Patterson-Lowry rhizomelic dysplasia. The typical findings of these cases on bone survey are isolated shortening and proximal metaphyseal enlargement and cupping of the bilateral humeri. The elder sister also has coxa vara deformity and dysplastic proximal femoral epiphyses on both sides. The younger sister has normal hip joint bones bilaterally, but her proximal femoral epiphyses are smaller than normal. All other bones of the sisters are of normal size and configuration. Our patients are two siblings, and their parents are first degree relatives, suggesting autosomal-recessive (AR) inheritance. The present patients help us to understand the genetic relationships and skeletal variabilities of this rare entity.

The radiological appearances of thalassaemia.

The skeletal changes of untreated thalassaemia result from ineffective erythropoiesis and expansion of the bone marrow and affect every part of the skeleton. These changes include osteoporosis, growth retardation, platyspondyly and kyphosis. Erythropoiesis occurs at extra-medullary sites, most commonly resulting in a paraspinal mass but occasionally affecting organs containing pluripotential stem cells. Repeated transfusion unaccompanied by iron chelation causes haemosiderosis; iron is deposited at various sites causing functional impairment. Iron-chelation therapy with desferrioxamine (DFX) prevents haemosiderosis but causes a skeletal dysplasia predominantly affecting the rapidly growing long bones, in particular the distal ulna, and causing irregularity and sclerosis of the physeal-metaphyseal junction and splaying of the metaphysis. DFX also exacerbates the observed growth retardation. DFX-induced skeletal dysplasia may herald toxicity, which is associated with visual and auditory impairment. Therefore, careful balancing of the transfusion regimen and iron-chelation therapy is required. Magnetic resonance imaging (MRI) is the most sensitive technique for the detection of DFX-induced dysplasia.

Radiographic characteristics of lower-extremity bowing in children.

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.

Patterns of bone diseases in transfusion-dependent homozygous thalassaemia major: predominance of osteoporosis and desferrioxamine-induced bone dysplasia.

OBJECTIVE: To study the radiographic skeletal changes in transfusion-dependent homozygous beta-thalassaemia. MATERIALS AND METHODS: This was a retrospective review of radiographs of 41 homozygous beta-thalassaemic patients over 3 years. These included 55 left hand radiographs for bone age, 37 chest radiographs, 7 scanograms of lower limbs, 8 knee radiographs and 3 skull radiographs. The radiographs were evaluated for the skeletal changes owing to medullary expansion, as well as for the skeletal dysplasia related to desferrioxamine therapy. The combined cortical width of the mid shaft of the second metacarpal was measured on left hand radiographs to assess osteoporosis. RESULTS: Sixteen patients had radiographic evidence of desferrioxamine-induced bone dysplasia. These included metaphyseal sclerosis in long bone ( n=16), irregular sclerosis at the costochondral junction ( n=3) and platyspondyly ( n= 1). Two patients had radiographic evidence of medullary expansion with widening of medulla and marked thinning of cortex in the tubular bones. Osteoporosis, as indicated by thinning of metacarpal cortex, was noted in 17 patients (8 with and 9 without desferrioxamine-induced bone dysplasia). CONCLUSIONS: With provision of the modern regime of regular transfusion and desferrioxamine chelation, desferrioxamine-induced bone dysplasia was a much more frequently detected radiographic abnormality in beta-thalassaemia major than radiographic features owing to medullary expansion. Osteoporosis, as indicated by thinned metacarpal cortices, remained a frequent feature irrespective of the status of the skeletal dysplasia.

Deferoxamine-induced dysplasia of the knee: sonographic features and diagnostic performance compared with magnetic resonance imaging.

OBJECTIVE: To evaluate the features and diagnostic performance of sonography in the assessment of deferoxamine-induced dysplasia of the knee. METHODS: The left knees of 32 patients with thalassemia who were receiving regular blood transfusions and chelation therapy were studied with sonography for signs of deferoxamine-induced bone dysplasia. Abnormal physeal and metaphyseal changes detected on sonography included notching at the metaphyseal corner, a blurred or irregular peripheral juxtaphyseal metaphyseal contour, and widening of the peripheral juxtaphyseal metaphyseal echogenic interface. The accuracy of sonography in diagnosing dysplasia was evaluated by using magnetic resonance imaging as the standard of reference. RESULTS: There were 14 true-positive findings, 10 true-negative findings, 7 false-negative findings, and 1 false-positive sonographic diagnosis of dysplasia, giving 67% sensitivity, 91% specificity, a 93% positive predictive value, and a 59% negative predictive value. CONCLUSION: Sonography was specific but only moderately sensitive in the diagnosis of deferoxamine-induced dysplasia at the knee when compared with magnetic resonance imaging.

Desferrioxamine-induced long bone changes in thalassaemic patients - radiographic features, prevalence and relations with growth.

AIM: To study the radiographic findings of desferrioxamine-induced bone dysplasia, its prevalence and relation to growth in thalassaemic patients. MATERIALS AND METHODS: A cross-sectional study was performed in 35 thalassaemic patients on a hypertransfusion scheme and chelation therapy at a dose not exceeding 50 mg/kg/day. Radiographs of the left hand taken for bone age assessment in consecutive patients over the past 12 months were evaluated for signs of desferrioxamine-induced bone dysplasia. The findings were correlated with data on growth, chelation and body iron content. RESULTS: Twelve of 35 patients had evidence of desferrioxamine-induced long bone dysplasia. There was no significant difference in the groups with and without radiographic evidence of bone dysplasia with respect to the height percentile at time of initiation of therapy, height percentile at time of radiography, skeletal age delay, age at starting chelation, chelation dose and duration, units of blood transfused, average chelation dose, and serum ferritin levels at time of radiography. Both groups showed a reduced percentile growth with a significantly greater reduction (P = 0.03) in the patients with dysplastic change. CONCLUSION: Desferrioxamine-induced bone dysplasia is associated with height reduction and can be seen in patients receiving desferrioxamine chelation therapy at doses of less than 50 mg/kg/day. Awareness of the diagnosis is of importance as reduction of the desferrioxamine dose may improve bone growth.

Early skeletal hyperostoses secondary to 13-cis-retinoic acid.

Prolonged therapy with retinoid drugs (chemically similar to vitamin A) often results in skeletal hyperostoses, similar to those seen in idiopathic skeletal hyperostosis. Eight patients, aged 5-26 years, with dermatologic disorders were treated with 13-cis-retinoic acid. Skeletal surveys were obtained before and during treatment. In 1 year, six of the eight patients had developed such skeletal hyperostoses in both axial and appendicular regions. The cervical spine was the most common site of involvement. None of the children demonstrated accelerated skeletal maturation. Two of the patients had mild musculoskeletal discomfort during this period. The findings indicate that high-dose 13-cis-retinoic acid therapy may cause skeletal hyperostoses, requiring radiographic monitoring during prolonged periods of treatment. An implication of these observations, relating to the etiology of idiopathic skeletal hyperostosis, is discussed.

[A case of osteopathia striata]. / A propos d'un cas d'ostéopathie striée.

We report a case of osteopathia striata, which is an osseous dysplasia with linear striations of the metaphyses of long bones. Our case is very unusual as there are no associated abnormalities of the bones. Osteopathia striata should not be mistaken for osteopoikilosis. Osteopathia striata is not only a peculiar roentgenologic feature: when it is diagnosed, other abnormalities should be looked for, especially cranial osteosclerosis, which may result in complications.

[A rare bone disease, but one not to be ignored: osteopathia striata]. / Une affection osseuse rare, mais à ne pas méconnaître: l'ostéopathie striée.

A case of osteopathia striata is reported, and this rare bone dysplasia reviewed. Normally asymptomatic, diagnosis of the disorder depends upon the finding of characteristic bone striation on radiological examination. A rarely isolated lesion, osteopathia striata is generally associated with other affections, which require systematic investigation in cases demonstrating typical radiological anomalies.

Late sequelae of infantile meningococcemia in growing bones of children.

Multiple, irregular ball-and-socket deformities at the ends of long bones were noted in four children several years after they had had meningococcemia. Even though these lesions were clinically unsuspected at the time of the fulminant disease, they were probably the result of ischemia secondary to septic emboli to the epiphyseal vessels, which occurred at the same time as soft-tissue necrosis elsewhere. The individual lesions were radiologically identical to the metaphyseal cupping that has been reported following trauma to the growth plate.

Epiphyseo-metaphyseal cupping following infantile scurvy.

A five year old girl presented with short femora, cupped distal metaphyses and flexion deformity of the knees suggesting previous epiphyseo-metaphyseal damage. The aetiology was suggested by finding a history of previous infantile scurvy with separated distal femoral epiphyses. The rarity of this complication and possible contributing factors are discussed.

Abnormal bone development and lameness associated with secondary copper deficiency in young cattle.

Lameness in a group of 5- to 12-month-old calves was found to be clinically, radiographically, and pathologically associated with abnormal bone development of the distal growth plates of the metacarpus and metatarsus. Copper concentrations in serum and liver were low. Serum calcium, phosphorus, and alkaline phosphatase values were normal. In pasture forage samples, sulfate, zinc, and molybdenum concentrations were high, whereas copper, calcium, and phosphorus concentrations were normal. Red blood cell (RBC) counts and hemoglobin values were within normal limits. Radiographic findings included a widened zone of cartilage and lipping of the medial and lateral areas of the physeal plate. Histologic findings included focal widenings of the growth plate consisting of tongues of uncalcified cartilage.