Deferoxamine-induced bone dysplasia in the distal femur and patella of pediatric patients and young adults: MR imaging appearance

Normal Bone Marrow and Non-neoplastic Systemic Hematopoietic Disorders in the Adult

This article provides an overview of the imaging appearances of normal adult bone marrow with an emphasis on magnetic resonance imaging. We also review the cellular processes and imaging features of normal developmental yellow-to-red marrow conversion and compensatory physiologic or pathologic red marrow reconversion. Key imaging features that differentiate between normal adult marrow, normal variants, non-neoplastic hematopoietic disorders, and malignant marrow disease are discussed, as well as posttreatment changes.

A Comparison of Arc of Motion, Radiological Parameters of the Wrist and Patient Rated Wrist Evaluation between Adult Transfusion Dependent Thalassemics and Normal Subjects

Background: Bony deformities and arthropathies have been noticed in thalassemia patients. The aim of this study is to compare the arc of motion and radiological parameters of the wrist and patient rated wrist evaluation (PRWE) between adult transfusion-dependent thalassemics and normal subjects.

Methods: An observational cross-sectional study was done in the department of orthopaedics over a period of 2 years where a total of 30 skeletally mature thalassemia major patients (group A) were assessed. The data was then compared with the data of demographically matched 30 healthy adults (group B). Arc of motion of the dominant wrist that included flexion, extension, radial and ulnar deviation, pronation and supination was measured using a handheld goniometer for both groups. Radiographs of the dominant wrist were obtained in both groups and used to determine the radial height, radial articular angle and carpal slip. PRWE was used to assess the function of the wrist. A p-value of <0.05 was considered statistically significant.

Results: Clinical abnormalities at the wrist joint were found in 80% of thalassaemia patients. There was a statistically significant increase in ulnar deviation, wrist extension and decrease in wrist flexion in group A compared to group B. Radiological abnormalities were found in 100% of thalassaemia patients. All the radiological parameters were significantly increased in group A compared to group B. There were no differences in PRWE scores between both groups.

Conclusion: Clinical and radiological changes of wrist joint occur in skeletally mature thalassaemia major patients due to shortened ulna compared to healthy adults. This may be due to disease itself, bone marrow expansion, osteopenia, drug (chelating agent) or iron toxicity. Understanding the changes at the wrist in patients with thalassemia major is important to increasing the life expectancy of these patients.

Level of Evidence: Level IV (Diagnostic)

Acute bone infarction: a rare complication in thalassemia

Acute bone infarction is a well-described complication in sickle cell hemoglobinopathy but it is rarely reported in patients with thalassemia. This report describes an 18-year-old man with homozygous β-thalassemia presenting with a fever and severe acute bilateral ankle pain. The acute onset of severe pain and fever were clinical mimics of infectious arthritis and osteomyelitis. Magnetic resonance imaging revealed acute bone infarction in the meta-diaphysis of bilateral tibias presenting as central unenhanced devitalized bone with T1-high signal intensity fluid in the subperiosteum and soft tissue. Characteristic imaging features are discussed, emphasizing the benefit of fat suppression pre-and post-intravenous gadolinium T1-weighted images. The etiologies of bone infarction in thalassemia are reviewed.

Deferoxamine-induced dysplasia-like skeletal abnormalities at radiography and MRI

BACKGROUND

Current thalassemia major treatment includes blood transfusion and iron chelation, which is associated with growth disturbances and radiographic changes in the long bone metaphyses.

OBJECTIVE

To explore and discuss the spectrum of deferoxamine-induced bone-dysplasia-like changes in children with thalassemia major in Egypt.

MATERIALS AND METHODS

We studied 59 Egyptian children with thalassemia major and generalized arthralgia. All started deferoxamine treatment at 3 years of age. We conducted skeletal survey and MRI of both knees in radiographically positive children. Each child's age, serum ferritin, age of onset and duration of therapy were compared with the radiologic findings.

RESULTS

Twenty-two (37.3%) children had variable degrees of skeletal dysplasia-like changes similar to those described with deferoxamine intake, mostly around the knees. Mild dysplasia-like changes were seen in 4 (18%) children; moderate changes were seen in 11 (50%) children and severe changes were seen in 7 (31.8%) children. No statistically significant relationships were detected between bone changes and the children's age, age of starting deferoxamine, duration of therapy, or serum ferritin level.

CONCLUSION

A wider spectrum of deferoxamine-induced bone-dysplasia-like changes was recognized despite delayed onset and small doses of therapy. These changes should be considered as a possible cause of arthropathy in children with thalassemia major, especially symptomatic children.

Iron deposits in the knee joints of a thalassemic patient

The overall prognosis for patients with β-thalassemia has improved considerably during the past decades mainly due to regular blood transfusions, improvements in chelation therapy, and enhanced surveillance with imaging studies examining iron overload and other clinical complications. However, the prolonged survival of these patients leads to the development of other health problems including degenerative diseases such as arthropathies, which require further attention since they have a significant impact on the quality of life. In the current case report, we present a 45-year-old white man with β-thalassemia complaining of non-traumatic pain and restriction in the range of motion of both knees. Magnetic resonance imaging (MRI) revealed a tear in the medial meniscus of the left knee as well as iron deposits in both knees. Histological findings confirmed the presence of hemosiderin in both joints. To our knowledge, this is the first reported case of macroscopically documented iron deposits in the knee joints of a patient with β-thalassemia using MRI.

Deferiprone-induced arthropathy in thalassemia: MRI findings in a case

Arthropathy is a well known side effect of the iron chelator deferiprone (L1); however, the imaging findings in deferiprone-induced arthropathy are not well known. In this article, we describe the typical radiographic and MRI findings in a patient receiving regular blood transfusions who developed arthropathy after long-term therapy with the oral iron chelator deferiprone (L1). Deferiprone primarily affects the articular cartilage and the changes include synovial thickening, articular cartilage thickening, and subchondral bone erosions.

Radiographic and MRI Features of Deferiprone-Related Arthropathy of the Knees in Patients with β-Thalassemia

OBJECTIVE

This study was undertaken to describe the radiographic and MRI appearances of arthropathy of the knees in 14 patients with beta-thalassemia major undergoing chelation therapy with deferiprone (L1).

MATERIALS AND METHODS

All available radiographs and MRI studies of the knees in 14 beta-thalassemia major patients (mean age, 16.3 years; age range, 7-33 years) undergoing chelation therapy with L1 were retrospectively assessed for changes in the synovium, cartilage, and bone. Imaging findings and signs of knee arthropathy were correlated with chelation therapy and average serum ferritin concentration.

RESULTS

Nine (64%) of the 14 patients developed arthralgia of the knees during treatment with L1. Abnormal imaging findings were present in all symptomatic and two asymptomatic patients (12/14, 86%) and included joint effusion, subchondral bone irregularity, and patellar beaks. Additional MRI findings were thickening and enhancement of the synovium; hypointense bands in the synovium; irregularly thickened epiphyseal and articular cartilage overlying subchondral bone defects; and, on T2-weighted sequences, hyperintense articular cartilage lesions. The degree of knee symptoms at the time of imaging did not reflect the severity of cartilage and subchondral bone changes.

CONCLUSION

Radiologic changes can be seen in L1-related arthropathy and should be recognized. MRI of the knees should be considered in symptomatic children and young adults with thalassemia undergoing L1 chelation therapy for iron overload.

MR imaging of children's knees

The spectrum of paediatric knee disorders ranges from developmental and growth disorders, traumatic derangement, inflammation, infection, and diffuse marrow disorder to neoplasm. We present in this pictorial review the MR imaging findings used to characterize these various diseases affecting the knee region of children and adolescents.