Electromyographic investigation of unstable patella before and after its realignment operation

Background:

Patellar dislocations are either due to superolateral contracture of the soft tissue or imbalance of the power between the vastus medialis (VM) and the vastus lateralis (VL). The imbalance of muscle power as an etiology of patellar dislocation has not been studied. Hence, we studied the recurrent, habitual and permanent dislocations of the patella with an electromyogram (EMG) of the vastus medialis, vastus lateralis, and pes anserinus, before and after realignment operations, to document the muscle imbalance and effectiveness of the realignment operation.

Materials and Methods:

An electromyographic investigation was carried out on the vastus medialis and vastus lateralis in nine recurrent, 20 habitual, and 13 permanent dislocations of the patella, before and after their realignment operations. Pes anserinus transposition, which acted as a medial stabilizer of the patella, was also investigated with an EMG study, to understand its role on patellar stability at 0°, 30°, 60°, 90°, 120°, 150°, and full flexion of the knee. The age of the patients varied from nine to 30 (mean 15) years. There were 24 males and 18 females. Twenty-six patellar dislocations were on the right and 16 were on the left side.

Results:

Electromyographic pictures reveal subnormal activity of the vastus medialis in all types of dislocations and similar activities of the vastus lateralis in permanent and habitual dislocations recorded pre operatively, which recovered to almost normal values postoperatively, at the mean one-year follow-up. Pes anserinus, which was used for medial stabilization of the patella after its realignment, maintained normal EMG activity before and after the operation.

Conclusion:

This study is significant for understanding the imbalance of muscle activities in patients with an unstable patella, which can be rectified without recurrence after pes anserinus transposition.     

Consequences of exposure to carcinogens beginning during developmental life

The increased incidence of cancer over the last 50-60 years may be largely attributed to two factors: the ageing of the population and the diffusion of agents and situations presenting carcinogenic risks. Today, we have entered into a new era in which populations are ever-increasingly exposed to diffuse carcinogenic risks, present not only in the occupational, but also in the general environment. We must now also consider an additional factor in the carcinogenic process, that is, the age in which exposure to carcinogenic risks begins. Apart from the paradigmatic cases of diethylstilboestrol and ionizing radiation, the available epidemiological data concerning the adult consequences of developmental exposure to carcinogens is very limited. However, important data have been provided by long-term experimental carcinogenicity bioassays conducted using rodents. This paper reports a selection of studies conducted in the laboratories of the Cesare Maltoni Cancer Research Center of the European Ramazzini Foundation in which exposure to the chemical agents vinyl acetate monomer, ethyl alcohol and aspartame was started during developmental life and continued into adulthood. The results of these studies provide supporting evidence that lifespan exposure to carcinogenic agents beginning during developmental life produces an overall increase in the carcinogenic effects observed. Moreover, when comparing prenatal and postnatal exposure, the data demonstrate that the development of cancers may appear earlier in life.     

Allocation of health care resources in the neonatal and perinatal area �CCPS Symposium 1996

There have been publically expressed concerns about the costs and allocation of neonatal and perinatal health care resources in Canada and elsewhere for the past 15 years. This paper reports information from a symposium held during the 1996 Canadian Paediatric Society (CPS) annual meeting sponsored by the CPS Section on Perinatal Medicine. Experts in perinatal epidemiology, health care economics, public policy and finance, and consumer perspectives on the outcomes of neonatal and perinatal intensive care explored the following questions: How should the need for health care resources in the neonatal and perinatal area be objectively determined? When there are competing needs between the maternal-newborn area and other areas, how should these be rationalized? What evidence should be used (or should be available) to support the present use of resources? What evidence should be available (or is needed) to change or introduce new uses of resources? The conclusions indicated that there are no generally accepted methods to determine the allocation of health care resources but that considerations need to include population characteristics, desired outcomes, achievable results, values, ethics, legalities, cost-benefit analyses and political objectives. Information from families and adolescents who required the use of high technology and/or high cost programs will contribute individual, family and societal values that complement cost-efficacy analyses.     

Prevalence of hypertension in patients on peritoneal dialysis: results of an Italian multicentre study.

BACKGROUND: The tenet that peritoneal dialysis is capable of either normalizing or improving blood pressure control in uraemic patients is based on outdated or monocentric experiences. Therefore, we assessed the prevalence of hypertension and the efficacy of antihypertensive therapy in a large, multicentric cohort of patients on peritoneal dialysis. METHODS: Twenty seven out of the 50 centres belonging to the Italian Co-operative Peritoneal Dialysis Study Group took part in the study. The main patient selection criteria were: peritoneal dialysis therapy for at least 3 months and no peritonitis or changes in dialysis technique for at least 1 month. Clinical blood pressure was measured according to WHO/ISH guidelines. Ambulatory blood pressure monitoring was carried out using a SpaceLabs 90207 recorder. Hypertension was defined according to WHO/ISH criteria and staged according to the criteria of the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure (JNC), 5th Report. Ambulatory blood pressure monitoring recordings were used to evaluate white-coat hypertension, blood pressure load and the dipping phenomenon. RESULTS: Five hundred and four subjects were evaluated. Hypertension was prevalent in 88.1% of the population, and 362 out of 444 hypertensive patients were on antihypertensive therapy. JNC staging revealed that 188 patients had moderate to severe hypertension. Blood pressure load was pathological in 77.3% of the patients receiving antihypertensive treatment. White-coat hypertension was identified in 9.1% of the hypertensive patients not on antihypertensive therapy, and 53.1% of the patients were non-dippers. CONCLUSIONS: The study demonstrates that hypertension is a dramatic, unsolved problem in uraemic patients treated with peritoneal dialysis, and casts doubts on the effectiveness of our current peritoneal dialysis strategies and pharmacological management of hypertension.     

Parathyroid imaging: comparison of double-tracer (T1-201, Tc-99m) scintigraphy and high-resolution US

Parathyroid scintigraphy using a double-tracer (T1-201, Tc-99m) subtraction technique depicted 17 of 23 (74%) parathyroid adenomas in patients with and without previous neck operations. High-resolution (10-MHz) ultrasound (US) depicted 18 (78%) of these adenomas. Average tumor size depicted by US was 17 X 10 X 8 mm (excluding a giant adenoma) and 19 X 10 X 9 mm by scintigraphy. Alone, neither modality was particularly sensitive in the depiction of primary hyperplasia of the parathyroid glands, but combined techniques were more effective than the use of a single modality. With both US and T1-201 scintigraphy, only two of 23 cases of parathyroid adenoma in the neck were missed, and none of the eight cases of secondary hyperplasia were missed. In 11 patients who had previously undergone neck surgery, parathyroid tumors were identified in eight by either US or double-tracer scintigraphy. Preoperative parathyroid imaging with double-tracer scintigraphy and high-resolution US is suggested for patients with hyperparathyroidism, particularly in those patients who have had previous parathyroid surgery.     

Intrauterine growth retardation: evaluation by magnetic resonance. Work in progress

Eleven high risk fetuses between 32 and 37 menstrual weeks gestational age were examined by magnetic resonance (MR) imaging. Serial obstetrical sonograms, birth weights, and serial postnatal examinations were obtained in all subjects. Sagittal MR spin echo images obtained using TR = 0.5 sec and TE = 28 msec were useful for assessing subcutaneous fat. Prospective estimates of fetal fat stores correlated with neonatal outcome better than sonographic measurements of fetal growth parameters or actual birth weight. MR appears to be a safe and useful technique that offers information complementary to obstetrical sonography when IUGR is suspected.     

Molecular epidemiology study of exogenous reinfection in an area with a low incidence of tuberculosis

In geographical areas with a low incidence of tuberculosis, recurrent tuberculosis is generally due to reactivation of the disease. However, the relative contribution of tuberculosis reinfection increases in parallel with the incidence of disease and is likely to depend on the epidemiological context: factors such as the spread of multidrug resistance, human immunodeficiency virus (HIV) infection, and immigration from developing countries could modify disease transmission in areas at low risk for tuberculosis. A molecular epidemiology study was performed in Lombardy, Northern Italy, where the incidence of tuberculosis is 17.5 cases per 100,000 persons. A total of 2,452 cases of culture-confirmed tuberculosis in 2,127 patients were studied. A group of 32 patients (1.5%), each of whom had two episodes of tuberculosis with cure as the outcome of the first episode and with more than 6 months between the two episodes, were studied by means of restriction fragment length polymorphism DNA fingerprinting analysis. For 5 of the 32 patients (16%), the DNA fingerprinting patterns of Mycobacterium tuberculosis strains responsible for the second episode did not match those of the corresponding isolates of the first episode, indicating exogenous reinfection. Two of these patients developed multidrug-resistant tuberculosis during the second episode, and in three cases the isolates belonged to clusters of M. tuberculosis strains spreading in the community. A fourfold-increased risk for reinfection was observed in immigrant patients compared to Italian subjects. In contrast, a higher risk of relapse rather than reinfection was evidenced in HIV-positive subjects and in patients infected with multidrug-resistant tuberculosis. Episodes of tuberculosis reinfection in areas with a low incidence of tuberculosis are rare compared to those in high-incidence geographical regions. In populations that have immigrated from high-risk areas, reinfection may represent a considerable contributor to the rate of recurrent tuberculosis. This finding emphasizes the importance of containing the spread of epidemic strains in close communities, in order to prevent changes in global tuberculosis trends for developed countries.     

Changes in first-line injectable disease-modifying therapy for multiple sclerosis: predictors of non-adherence,switching, discontinuation,and interruption of drugs

Neurological Sciences - This study was aimed to describe changes of Disease-Modifying Treatments (DMT) in an Italian cohort of patients with multiple sclerosis (MS) and to identify predictors of...