Assessment of hindfoot deformity by three-dimensional MRI in infant club foot.
In 12 infants aged under 16 months with unilateral club foot we used MRI in association with multiplanar reconstruction to calculate the volume and principal axes of inertia of the bone and cartilaginous structures of the hindfoot. The volume of these structures in the club foot is about 20% smaller than that in the normal foot. The reduction in volume of the ossification centre of the talus (40%) is greater than that of the calcaneus (20%). The long axes of both the ossification centre and the cartilaginous anlage of the calcaneus are identical in normal and club feet. The long axis of the osseous nucleus of the talus of normal and club feet is medially rotated relative to the cartilaginous anlage, but the angle is greater in club feet (10 degrees v 14 degrees). The cartilaginous structure of the calcaneus is significantly medially rotated in club feet (15 degrees) relative to the bimalleolar axis. The cartilaginous anlage of the talus is medially rotated in both normal and club feet, but with a smaller angle for club feet (28 degrees v 38 degrees). This objective technique of measurement of the deformity may be of value preoperatively. (+info)
Intra-articular displaced fractures of the calcaneus. Operative vs non-operative treatment.
Twenty-eight patients with displaced intra-articular fractures of the calcaneus treated by open reduction and fixation were compared with 30 patients with similar fractures treated conservatively. Judged by the clinical and radiographic criteria results were more satisfactory in the surgical group than in the nonoperative group, although high rates of poor results were encountered in both groups. (+info)
Ultrasound study of heel to calcaneum depth in neonates.
AIM: To investigate whether it would be safe to extend the currently recommended area of sampling to the whole heel in neonates. METHODS: Eighty newborn infants were studied, weight range 0.56 to 4.34 kg, gestation 24 to 42 weeks. Ultrasound scanning was used to measure the shortest distance between the skin and the perichondrium of the calcaneum. RESULTS: The shortest depth of perichondrium was in the centre of the heel and ranged from 3 to 8 mm. In 78 of the 80 infants the distance was 4 mm or more. There was a small but significant positive correlation with weight. CONCLUSIONS: Standard automated lancets for preterm use that puncture to a depth of 2.4 mm may be safely used anywhere over the plantar surface of the heel. The posterior aspect of the heel should be avoided. Reducing the density of heel pricks should reduce the associated pain. (+info)
Impact of peripheral neuropathy on bone density in patients with type 1 diabetes.
OBJECTIVE: To investigate whether peripheral neuropathy (PN), as part of the microangiopathic complex, affects bone mineral density (BMD) of the peripheral or the axial skeleton in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: Three study groups were examined. Group 1 comprised 21 males with type 1 diabetes and severe PN with a mean (range) duration of diabetes of 28 (9-59) years and an HbA1c of 8.2% (6.3-10.4). Group 2 comprised 21 male type 1 diabetic patients with absent or mild PN matched to patients of group 1 regarding age, weight, and duration of diabetes. Group 3 comprised 21 control subjects. BMD was measured by dual-energy x-ray absorptiometry (DEXA) and by quantitative ultrasound of the calcaneus. PN was determined by biothesiometry. Levels of physical activity were assessed through guided questionnaires. RESULTS: In group 1, BMD was significantly reduced at all measured sites, compared with an expected Z score of 0 (spine, -1.01 +/- 0.34; femur, -0.94 +/- 0.25; forearm, -1.10 +/- 0.36). To a lesser extent, but still significantly, group 2 also showed reduced BMD values (spine, -0.60 +/- 0.26; femur, -0.55 +/- 0.25; forearm, -1.05 +/- 0.36), whereas group 3 had normal BMD values (-0.23 +/- 0.25, -0.10 +/- 0.21, -0.07 +/- 0.25, respectively). Group 1 had lower mean BMD levels than group 2 and group 3 at all measured sites, but a significant difference was found only between groups 1 and 3 at the site of the femur (analysis of variance, P < 0.05). Broadband ultrasound attenuation (BUA) of the calcaneus was significantly reduced in group 1 compared with groups 2 and 3 (108 +/- 3 vs. 115 +/- 2 and 115 +/- 2). Significant correlations between all DEXA measurements and BUA were demonstrated in both groups 1 and 2 (r values between 0.54 and 0.75). No significant differences in physical activity levels or body composition were demonstrated between the two patient groups. CONCLUSIONS: The present results suggest that in patients with type 1 diabetes, PN may be an independent risk factor for reduced BMD in the affected limbs as well as in the skeleton in general. (+info)
Comparison of quantitative ultrasound in the human calcaneus with mechanical failure loads of the hip and spine.
OBJECTIVE: Quantitative ultrasound of the calcaneus is used clinically for evaluating bone fracture risk, but its association with the mechanical properties at other skeletal sites is not well characterized. The objective was therefore to determine its predictive ability of the mechanical failure loads of the proximal femur and lumbar spine. METHOD: In 45 human cadavers (29 males and 16 females, aged 82.5 +/- 9.6 years), we determined the speed of sound, broadband ultrasonic attenuation (BUA) and the empirical stiffness index, using a commercial quantitative ultrasound scanner. The proximal femora and the fourth vertebral body were excised and loaded to failure in a testing machine. RESULTS: Femoral failure loads ranged from 933 to 7000 N and those of the vertebrae from 1000 to 7867 N, their correlation being 0.51 in females and -0.08 in males. Forty percent of the variability of femoral, but only 24% of the variability of the vertebral fracture loads could be predicted with calcaneal speed of sound. In the femur, a combination of speed of sound and BUA improved the prediction (r2 = 50-60%), but not in the spine. CONCLUSIONS: The study provides experimental evidence that calcaneal quantitative ultrasound is capable of predicting mechanical failure at other skeletal sites and has potential to identify patients at risk from osteoporotic fracture. The different association of quantitative ultrasound with femoral and vertebral failure may result from the influence of the cortical bone and a higher microstructure-related similarity of the calcaneus and the femur. (+info)
Total dislocations of the navicular: are they ever isolated injuries?
Isolated dislocations of the navicular are rare injuries; we present our experience of six cases in which the navicular was dislocated without fracture. All patients had complex injuries, with considerable disruption of the midfoot. Five patients had open reduction and stabilisation with Kirschner wires. One developed subluxation and deformity of the midfoot because of inadequate stabilisation of the lateral column, and there was one patient with ischaemic necrosis. We believe that the navicular cannot dislocate in isolation because of the rigid bony supports around it; there has to be significant disruption of both longitudinal columns of the foot. Most commonly, an abduction/pronation injury causes a midtarsal dislocation, and on spontaneous reduction the navicular may dislocate medially. This mechanism is similar to a perilunate dislocation. Stabilisation of both medial and lateral columns of the foot may sometimes be essential for isolated dislocations. In spite of our low incidence of ischaemic necrosis, there is always a likelihood of this complication. (+info)
Fibrous dysplasia arising from the calcaneus.
A case of an 18-year-old woman with fibrous dysplasia arising in the calcaneus, which is extremely rare, is reported, with the emphasis placed on differential diagnosis from low-grade central osteosarcoma. She had a severe pain in her left ankle after sprain. Plain radiographs showed a radiolucent lesion measuring 6.3 x 2.5 cm with a sclerotic margin in the left calcaneus. CT scans showed a well-defined lytic lesion with disruption of the lateral cortex and an ossification or calcification in its center. On MR imaging, the lesion had isointensities and high intensities on T1 and T2 weighted images, respectively, but its central portions showed lower intensities both on T1 and T2 weighted images. The lesion was enhanced with gadolinium except for the central portions. The specimen obtained by open biopsy consisted of fibrous tissue and foci of irregular woven bone. None of the nuclear atypia, mitoses, longitudinal stream of bone or invasive nature of growth was detected. The diagnosis of fibrous dysplasia was histologically made. The lesion was curetted and packed with autogenous bone chips. No evidence of recurrence was noted postoperatively. (+info)
Elderly cohort study subjects unable to return for follow-up have lower bone mass than those who can return.
Longitudinal studies of osteoporosis in older persons may underestimate bone loss because of a lack of follow-up measurements on subjects too frail to return. The authors addressed this possible bias as part of the population-based Framingham Study; in 1996-1997, they used quantitative ultrasound to assess the bone status of elderly subjects regardless of their ability to return to the clinic. Broadband ultrasound attenuation (BUA) and speed of sound of the calcaneus (heel) were measured in 433 subjects at the Framingham, Massachusetts, clinic and in 167 subjects at their homes or nursing homes. All ultrasound parameters were measured with intramachine coefficients of variation of <6.0%. The mean BUA for those subjects evaluated at the clinic was higher than for those measured at home (9.2% higher for men, p = 0.081; 8.6% higher for women, p = 0.034). After adjustment for age and weight, the differences in BUA were no longer significant. Among the elderly subjects participating in this longitudinal cohort study, those who were unable to return for follow-up were older, weighed less, and had a lower BUA than those who did return, suggesting that longitudinal studies of changes in bone mass with aging may underestimate the true population values. (+info)