No abstract

Background: During routine follow-up of patients treated with a three-piece stainless-steel modular femoral nail, osteolysis and periosteal reaction around the modular junctions of some of the nails were noted on radiographs. The purpose of this study was to evaluate the prevalence, etiology, and clinical relevance of these radiographic findings. Methods: Forty-four femoral fractures or nonunions in forty-two patients were treated with a modular stainlesssteel femoral intramedullary nail. Seventeen nails were excluded, leaving twenty-seven intramedullary nails in twenty-seven patients for this study. All patients had had a femoral diaphyseal fracture; nineteen had had an acute fracture and eight, a nonunion. These twenty-seven patients returned for radiographs, a physical examination, assessment of functional outcomes, assessment of thigh pain with a visual analog scale, determination of serum chromium levels, and nail removal if desired. A control group of sixteen patients treated with a one-piece stainless-steel femoral intramedullary nail was evaluated with use of the same outcome measures and was compared with the group treated with the modular femoral nail with regard to prevalence of thigh pain and serum chromium levels. Twelve modular femoral nails were removed according to the study protocol. The modular nail junctions were analyzed for corrosion products, and histopathologic analysis of tissue specimens from the femoral canal was performed. Results: The twenty-seven patients were seen at a mean of twenty-one months after fracture fixation; twenty-six of the twenty-seven fractures healed. Twenty-three femora had at least one of three types of abnormalitiesosteoly-sis, periosteal reaction, or cortical thickeninglocalized to one or both modular junctions. Eighteen patients had severe reactions, defined as osteolysis of ≥2 mm, cortical thickening of ≥5 mm, and/or a periosteal reaction (group 1). Nine patients had mild or no reactions (group 2). Serum chromium levels in group 1 (mean, 1.27 ng/ mL; range, 0.34 to 3.12 ng/mL) were twice as high as those in group 2 (mean, 0.53 ng/mL; range, 0.12 to 1.26 ng/mL). However, this difference did not reach significance with the numbers available. The differences in serum chromium levels between group 1 and the control group with a one-piece nail (mean, 0.26 ng/mL; range, 0.015 to 1.25 ng/mL) (p < 0.01) and a control group without an implant (mean, 0.05 ng/mL; range, 0.015 to 0.25 ng/ mL) (p < 0.01) were significant. The level of thigh pain recorded on the visual analog scale was also significantly different between group 1 and the control group with a one-piece implant (p = 0.03). Retrieved modular nails had signs of fretting corrosion as well as stainless-steel corrosion products adherent to the junction where the osteolysis occurred. Histologic and spectrographic analysis revealed two types of corrosion products that were consistent with stainless-steel within the peri-implant tissue and were associated with a foreign-body granulomatous response. Conclusions: The ...

The purpose of this study was to make a direct comparison between lumbar spine radiographs of incoming college football players and of an age-matched control group to determine whether there is a higher prevalence of lumbar spine abnormalities in football players before competing at the Division I level. We reviewed 187 lumbar spine radiographs. Of these, 104 were taken as a standard part of the preparation physical examination for incoming college football players. The remaining 83 radiographs were taken during routine preemployment physicals at a local factory. Each radiograph was read independently by three separate orthopaedic radiologists in a blinded fashion. Data were collected and statistically evaluated for 13 variables. The rate of spondylolysis was only 4.8% in our group of athletes and 6.0% in the control group (not significantly different). Only in the category of degenerative changes was a significant difference found. The control group had a 16.9% incidence of disk space narrowing and spurring and the football players had a 6.7% incidence. The remainder of the variables were not significantly different between the two groups. Our findings differ from previously published reports and indicate that football players entering college at the Division I level may have a similar prevalence of radiographic lumbar spine abnormalities, including spondylolysis and spondylolisthesis, as age-matched controls.

blood pressure was 220/170 mm Hg, he had grade IV hypertensive retinopathy, and the serum creatinine level was 5 0 mg/100 ml. He still felt well. Diazoxide 300 mg intravenously lowered the blood pressure, but methyldopa, debrisoquin, reserpine, and clonidine failed to maintain control. There was pronounced orthostatic hypotension, but the blood pressure in the lying posture was high. Renal biopsy showed severe hypertensive nephropathy with many hyalinized glomeruli, the serum creatinine rose to 11-3 mg/100 ml, and there were bouts of left ventricular failure. It was decided to perform bilateral nephrectomy, and an infusion of sodium nitroprusside readily controlled the blood pressure (Table II). At the time of writing he was awaiting a renal transplant and his blood pressure was under control without drugs.Case 4.-A 48-year-old man had a 10-month history of hypertension and renal failure. Control of hypertension had become increasingly difficult, and on admission the blood pressure was 230/ 150 mm Hg, the serum creatinine 13-0 mg/100 ml, and there was a grade IV hypertensive retinopathy. Pentolinium, 25 mg subcutaneously in 12 hours, had no effect on the blood pressure, but it fell briefly to 90/70 mm Hg after 300 mg of diazoxide intravenously. Sodium nitroprusside was then used with good effect. It was continued during peritoneal dialysis preparatory to bilateral nephrectomy, but there were pronounced swings in blood pressuresystolic 80-260, mean 156 (S.D.43); diastolic 50-160, mean 112 (S.D.28)-with severe anginal pain. There was no evidence of myocardial infarction. Sodium nitroprusside was continued after dialysis ended and blood pressure control again became satisfactory and the anginal pain ceased. After bilateral nephrectomy his blood pressure returned to normal without further therapy, but unfortunately he died six days after the operation from bronchopneumonia and septicaemia.Discussion Sodium nitroprusside has a direct depressant effect on vascular musculature, independent of the nervous system (Page et al., 1955). The effect is immediate and ends when the infusion is stopped. The latter property is of special value in patients in whom the cause of hypertension is to be abruptly removed. I have not used the drug during surgery for a phaeochromocytoma, but it would seem to be the drug of choice for this purpose and for when controlled lowering of blood pressure is needed during surgery. Though it is less effective in normotensive subjects than in hypertensives it produces a fall of blood pressure, and Kaneko et al. (1967) used it rapidly to lower the blood pressure in normotensive subjects to study renin release.The drug is virtually non-toxic during short-term use. Long-term toxic effects are due to accumulation of thiocyanate, to which sodium nitroprusside is converted. One case reported by Nourok et al. (1964) developed high serum levels of thiocyanate and features of hypothyroidism after 21 days, which improved when the nitroprusside infusion was stopped. The longest period of infusion in my cases ...

ummary: Bacterial proliferation in dialysis fluid during haemodialysis may be associated with rigors, hypotension, and bacteraemia. Investigations carried out in a period in which rigors were particularly common showed the source of bacteria to be parts of the gasket system of the Kiil dialyser, areas that are inaccessible to disinfectants.