Early results of a prospective study on the pyrolytic carbon (pyrocarbon) Amandys? for osteoarthritis of the wrist

INTRODUCTION

The preliminary results of a pyrocarbon interpositional radiocarpal implant in a small cohort of patients were reviewed. As it is currently only a limited release product, we describe to potential users early complications and negative outcomes.

METHODS

Patients were assessed using pain levels, ranges of motion, grip strength, type of and time to return to work as well as pre-operative and post-operative DASH (Disabilities of the Arm, Shoulder and Hand) scores. Radiographs were taken and patient satisfaction was recorded.

RESULTS

All six patients were contacted. One was not satisfied. Three had reduced motion. None experienced squeaking. There were no immediate or late post-operative complications. There was one early volar displacement of an implant.

CONCLUSIONS

Although our early results are somewhat encouraging, further and longer studies are warranted before supporting the use of this particular pyrocarbon implant as a primary procedure.     

Rising incidence of type 1 diabetes in Scottish children, 1984-93. The Scottish Study Group for the Care of Young Diabetics

OBJECTIVES: To calculate the incidence of type 1 diabetes in Scottish children aged less than 15 years between 1984 and 1993; to examine changes in incidence; and to calculate the prevalence of diabetes at the end of this period. DESIGN: Three data sources were used to construct the Scottish Study Group for the Care of Young Diabetics register: active reporting of all new cases; reports from the Scottish Morbidity Register 1; and local registers. SUBJECTS: All children resident in Scotland diagnosed with primary insulin dependent diabetes mellitus when less than 15 years of age between 1984 and 1993. MAIN OUTCOME MEASURES: Annual incidence and prevalence rate for Scotland; time trend in incidence over the 10 years; differences in incidence between the three different age groups; and completeness of the register. RESULTS: The average annual incidence for Scotland was 23.9/100,000 children. The prevalence rate was 1.5/1000 in 1993. A total of 2326 cases was identified from the three sources. Capture-recapture analysis suggests a case ascertainment of 98.6%. The annual incidence rates increased at a rate of 2% each year (rate ratio = 1.02, 95% confidence interval (CI) 1.01 to 1.03). The incidence was higher in boys than girls (rate ratio = 1.08, 95% CI 1.00 to 1.18), and the incidence rates increased with age: 15.3/100,000/year for age 0-4 years, 24.4/ 100,000/year for age 5-9 years, and 31.9/ 100,000/year for age 10-14 years. CONCLUSIONS: The incidence of type 1 diabetes in Scotland is increasing and the prevalence is relatively high. These findings have important implications for health service resource allocation. The Scottish Study Group for the Care of Young Diabetics' register provides a base for monitoring and research.     

Spontaneous correction of femoral torsion. Diaphyseal osteotomies studied in kittens

Inward or outward torsion of about 25 degrees was produced in the right femur of kittens by midshaft osteotomy and plate fixation. The left femurs served as controls. The anteversion angle of the femoral necks was measured in axial radiographs taken preoperatively and up to 58 weeks postoperatively. As the bones grew in length, the difference in the anteversion angle between matched femurs was gradually corrected.     

Nickel and iron in saliva of patients with fixed orthodontic appliances

Saliva was obtained from patients receiving treatment with fixed orthodontic appliances. One saliva sample was taken without appliances, and another at least 3 weeks after placement. In some patients samples were also taken immediately after insertion of the appliance. Nickel and iron were quantified by electrothermal atomic absorption spectroscopy. There was a large scatter in the results. No statistically significant differences were found either in the concentrations or in absolute masses of nickel or iron in samples taken without appliances and in those obtained when the appliances had been in the mouth for at least 3 weeks. For samples taken immediately after placement of the appliance, there was a significant increase in both concentrations and masses of nickel and iron. It thus seems that there is a high initial release of metals, and the effect diminishes with time.     

The angiomatous polyp and the angiofibroma: two different lesions

Five cases of angiomatous polyps that were initially interpreted as angiofibromas are presented. Although they are similar to angiofibromas, angiomatous polyps have a distinctly different pattern of growth on computed tomography and a different angiographic appearance. In addition, they are more easily extirpated at surgery than are angiofibromas.     

Outpatient lumbar myelography. Initial results in 79 examinations using a low-dose metrizamide technique

Seventy-nine patients underwent lumbar myelography on an outpatient basis, with a low (3.75 g) dose of metrizamide as the radiocontrast agent and a 25-gauge spinal needle used for lumbar puncture. No patient experienced significant neurotoxicity following the examination; 70.8% (56 of 79) experienced minimal (23%) or no (48%) side effects. Three patients (3.8%) were admitted to the hospital for management of common side effects (headache, nausea/vomiting, back pain). We obtained postmyelographic computed tomographic scans on 96% (76 of 79) of the patients. Our initial results suggest that outpatient lumbar myelography is safe and can be performed with a very acceptable incidence of side effects.     

Dimensional changes of periodontal dressings.

The linear dimensional changes of three commercial periodontal dressings were measured during 24 hours. The dressings revealed different degrees of dimensional changes, which may indicate that exhibit variations in adaptation to wound surfaces.     

Strain shielding 12 weeks after femoral reaming and nailing in rats

The purpose of this study was to investigate the in vivo strain-shielding in rat femora 12 weeks after intramedullary nailing with either flexible or rigid implants. Five days prior to death, unidirectional strain gauge units were implanted on the anterior bone surface bilaterally. Median strain values of reamed only and polyacetal-nailed femora ranged from 67 to 90 percent of the intact side. Removal of polyacetal nails and sham operations gave negligible changes in strain. Strain of the steel-nailed femora was 51 percent of the intact side. Removal of nails increased strain to 91 percent of the intact side. Testing of femora after removal of implants revealed stiffness of 116 and 103 percent of normal in reamed-only and polyacetal-nailed groups, respectively. Stiffness in the steel-nailed group was reduced to 85 percent of normal. None of these changes were statistically significant. This study indicates that rigid intramedullary nails cause strain shielding at the anterior, mid-diaphyseal surface of rat femora 12 weeks after insertion. Removal of rigid implants seems to restore the loading configuration immediately.