Ossifying chronic subperiosteal haematoma of the iliac bone.

Ossifying subperiosteal haematoma is a rare finding which may mimic more aggressive pathologies. We present the case of a 17-year-old boy with a subperiosteal haematoma of the iliac bone and discuss the imaging features.

Isolated atrophy and fatty infiltration of supraspinatus: A rare finding.

Isolated atrophy and fatty infiltration of supraspinatus is very rare. We report the case of a 53 year old male with isolated atrophy and complete fatty replacement of supraspinatus and discuss potential aetiologies.

Gout on CT of the feet: A symmetric arthropathy.

INTRODUCTION: The aim of this study was to assess the distribution of bone erosions in the feet of patients with gout using CT and thereby to test the hypothesis that gout is an asymmetric arthropathy. METHODS: CT scans of both feet were obtained from 25 patients with chronic gout. CT scans were scored for bone erosion using a semi-quantitative method based on the rheumatoid arthritis MRI scoring system (RAMRIS). CT bone erosion was assessed at 22 bones in each foot (total 1,100 bones) by two independent radiologists. Symmetry was assessed by two methods: (i) comparing right and left foot scores for each patient; and (ii) calculating the proportion of paired joints with or without erosions. RESULTS: Observer agreement was excellent (intra-class correlation coefficient 0.92). In the group overall, the difference in scores between the feet was not significant (Student's t-test P = 0.8). In 17 of 25 patients, the difference in erosion scores between the two feet was less than the inter-observer difference. In 24 of 25 patients, the proportion of paired joints was greater than 0.5, indicating symmetric disease. CONCLUSIONS: Erosive disease from gout is, in fact, a symmetric process in our patient group. This finding is contrary to the established view of gout as an asymmetric arthritis and lends new insight into the behaviour of this common disease.

Development of a computed tomography method of scoring bone erosion in patients with gout: validation and clinical implications.

OBJECTIVES: To develop a method of scoring bone erosion in the feet of patients with gout using CT as an outcome measure for chronic gout studies, consistent with the components of the OMERACT filter. METHODS: Clinical assessment, plain radiographs and CT scans of both feet were obtained from 25 patients with chronic gout. CT scans were scored for bone erosion using a semi-quantitative method based on the Rheumatoid Arthritis MRI Scoring System (RAMRIS). CT bone erosion was assessed at 22 bones in each foot (total 1100 bones) by two independent radiologists. A number of different models were assessed to determine the optimal CT scoring system for bone erosion, incorporating the frequency of involvement and inter-reader reliability for individual bones. RESULTS: An optimal model was identified with low number of bones required for scoring (seven bones/foot), inclusion of bones over the entire foot, high reliability and ability to capture a high proportion of disease. This model included the following bones in each foot: first metatarsal (MT) head, second to fourth MT base, cuboid, middle cuneiform and distal tibia (range 0-140). Scores from this model correlated with plain radiographic damage scores (r = 0.86, P < 0.0001) and disease duration (r = 0.42, P < 0.05). Scores were higher in those with clinically apparent tophaceous disease than in those without tophi (P < 0.0001). CONCLUSIONS: We have developed a preliminary method of assessing bone erosion in gout using conventional CT. Further testing of this method is now required, ideally in prospective studies to allow analysis of the sensitivity to change of the measure.