Automatic bone age assessment for young children from newborn to 7-year-old using carpal bones.
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A computer-aided-diagnosis (CAD) method has been previously developed based on features extracted from phalangeal regions of interest (ROI) in a digital hand atlas, which can assess bone age of children from ages 7 to 18 accurately. Therefore, in order to assess the bone age of children in younger ages, the inclusion of carpal bones is necessary. However, due to various factors including the uncertain number of bones appearing, non-uniformity of soft tissue, low contrast between the bony structure and soft tissue, automatic segmentation and identification of carpal bone boundaries is an extremely challenging task. Past research works on carpal bone segmentation were performed utilizing dynamic thresholding. However, due to the limitation of the segmentation algorithm, carpal bones have not been taken into consideration in the bone age assessment procedure. In this paper, we developed and implemented a knowledge-based method for fully automatic carpal bone segmentation and morphological feature analysis. Fuzzy classification was then used to assess the bone age based on the selected features. This method has been successfully applied on all cases in which carpal bones have not overlapped. CAD results of total about 205 cases from the digital hand atlas were evaluated against subject chronological age as well as readings of two radiologists. It was found that the carpal ROI provides reliable information in determining the bone age for young children from newborn to 7-year-old. (+info)
The usefulness of CT for patients with carpal bone fractures in the emergency department.
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OBJECTIVE: The wrist is the most commonly injured joint in the body. However, wrist injuries are often missed in the emergency department (ED). If the fracture is not diagnosed and remains untreated, the patient runs a considerable risk of chronic disability. The utility of CT as an aid in the diagnosis of carpal bone fracture was investigated. MATERIALS AND METHODS: A retrospective analysis was performed of patients who underwent CT and plain radiography for wrist injury in the ED between March 2003 and February 2006. Plain radiograph interpretations were classified into three groups: (1) the definite fracture group, (2) the no fracture group, and (3) the ambiguous fracture group. The CT results were analysed in relation to the classification of the plain radiograph interpretation. The final diagnoses reviewed from the medical records were used as the reference standard. RESULTS: 36 carpal fractures in 33 patients were identified from 45 patients who underwent plain radiography and CT. The interpretations of plain radiographs were classified into definite fractures (n = 10), ambiguous fractures (n = 15) and no fractures (n = 20). When both the definite fracture and ambiguous fracture groups were considered positive, the sensitivity and specificity were 69.7% and 83.3%, respectively. The sensitivity and specificity of CT scans were both 100%. CONCLUSION: Emergency physicians should consider CT of the wrist after plain radiography when patients with suspected carpal fracture show normal radiographic findings. (+info)
A three-dimensional quantitative analysis of carpal deformity in rheumatoid wrists.
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We have measured the three-dimensional patterns of carpal deformity in 20 wrists in 20 rheumatoid patients in which the carpal bones were shifted ulnarwards on plain radiography. Three-dimensional bone models of the carpus and radius were created by computerised tomography with the wrist in the neutral position. The location of the centroids and rotational angle of each carpal bone relative to the radius were calculated and compared with those of ten normal wrists. In the radiocarpal joint, the proximal row was flexed and the centroids of all carpal bones translocated in an ulnar, proximal and volar direction with loss of congruity. In the midcarpal joint, the distal row was extended and congruity generally well preserved. These findings may facilitate more positive use of radiocarpal fusion alone for the deformed rheumatoid wrist. (+info)
Computerized geometric features of carpal bone for bone age estimation.
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BACKGROUND: Bone age development is one of the significant indicators depicting the growth status of children. However, bone age assessment is an heuristic and tedious work for pediatricians. We developed a computerized bone age estimation system based on the analysis of geometric features of carpal bones. METHODS: The geometric features of carpals were extracted and analyzed to judge the bone age of children by computerized shape and area description. Four classifiers, linear, nearest neighbor, back-propagation neural network, and radial basis function neural network, were adopted to categorize bone age. Principal component and discriminate analyses were employed to improve assorting accuracy. RESULTS: The hand X-ray films of 465 boys and 444 girls served as our database. The features were extracted from carpal bone images, including shape, area, and sequence. The proposed normalization area ratio method was effective in bone age classification by simulation. Besides, features statistics showed similar results between the standard of the Greulich and Pyle atlas and our database. CONCLUSIONS: The bone area has a higher discriminating power to judge bone age. The ossification sequence of trapezium and trapezoid bones between Taiwanese and the atlas of the GP method is quite different. These results also indicate that carpal bone assessment with classification of neural networks can be correct and practical. (+info)
Can carpal malalignment predict early and late instability in nonoperatively managed distal radius fractures?
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The purpose of this study was to assess the frequency of carpal instability as a concomitant lesion in distal radius fractures and identify other factors including carpal malalignment in an attempt to predict the final radiological outcome more accurately following conservative treatment of distal radius fractures. An observational study from patient records and standardised radiological follow-up examinations as data sources was used. The alignment of each wrist was checked radiographically immediately post-reduction and subsequently at 1- and 6-week follow-up assessments. Serial measurements of radial length, dorsal tilt, radial inclination, scapho-lunate, radio-lunate, radioscaphoid, scapho-capitate angles and effective radiolunate flexion angle were made. Regression analysis showed high correlation among the severity of axial shortening, pre-reduction dorsal angulation and radio-carpal malalignment pattern with early loss of reduction at 1 week. We found the age, severity of axial radial shortening, dorsal angulation, presence of dorsal comminution and radio-carpal malalignment pattern to be significant predictors of adverse radiological outcome at 6 weeks (late instability). Our study highlights the importance of radio-carpal instability pattern on post-reduction radiographs as a predictor of early and late instability. (+info)
A modification of the Omeract RA MRI score for erosions for use with an extremity MRI system with reduced field of view.
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OBJECTIVES: To develop and test the reliability of a modified version of the OMERACT rheumatoid arthritis magnetic resonance imaging score (RAMRIS) for erosions using extremity MRI (eMRI) with reduced field of view (RAMRIS-RV). METHODS: Using a MagneVu 0.2 T machine, the preliminary RAMRIS-RV assessed erosions in metacarpophalangeal (MCP) joints 2-3, bases of metacarpal (MC) 2-5, and all wrist bones excluding base MC 1, pisiform and trapezium. T1 weighted images of >/=500 MCP and wrist bony sites from a mixed severity RA and control cohort were evaluated. An inter-reader reliability study evaluating 300 wrist and 160 MCP bony sites was then performed. RESULTS: Mean per cent exact (and close) agreement results were as follows: MCP proximal sites 83.5 (96.2), MCP distal 54.4 (77.2), bases MC 2-4 85.2 (96.7), carpal bones 79.0 (92.1), distal radius/ulna 66.4 (87.8). The base of MCP 5 was visualised in +info)
Wide excision and ulno-carpal arthrodesis for primary aggressive and recurrent giant cell tumours.
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Twenty-five patients underwent wide resection of the distal radial giant cell tumours (GCTs) followed by ulno-carpal arthrodesis. There were 15 male and ten female patients, with an average age of 21.5 years. Tumours included ten primary aggressive and 15 recurrent GCTs. Mean follow up was 2.4 years. Pain, swelling and reduced range of movement (ROM) were noted. Average time to fusion was 7.6 months. Five patients had persistent pain in the proximal forearm. Grip strength was 65% compared to the uninvolved side. Two patients had superficial wound infection, two underwent additional bone grafting and three implant removals due to hardware prominence were carried out. There was no evidence of carpal instability or arthritis on clinical or radiological examination at the time of final follow up. Fusion of the carpus to the ulna is a simple method of producing a painless stable wrist, though at the expense of mobility. The procedure allows wide resection with a lower rate of recurrence. Pain in the proximal forearm seems to persist for 3 to 4 months only to improve at subsequent follow up. The procedure provides a valid option for the management of primary aggressive and recurrent GCTs of distal radius. (+info)
The primitive wrist of Homo floresiensis and its implications for hominin evolution.
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Whether the Late Pleistocene hominin fossils from Flores, Indonesia, represent a new species, Homo floresiensis, or pathological modern humans has been debated. Analysis of three wrist bones from the holotype specimen (LB1) shows that it retains wrist morphology that is primitive for the African ape-human clade. In contrast, Neandertals and modern humans share derived wrist morphology that forms during embryogenesis, which diminishes the probability that pathology could result in the normal primitive state. This evidence indicates that LB1 is not a modern human with an undiagnosed pathology or growth defect; rather, it represents a species descended from a hominin ancestor that branched off before the origin of the clade that includes modern humans, Neandertals, and their last common ancestor. (+info)