[Ultrasound bone densitometry in children and adolescents; Italian refence curves with multi-site device (Omnisense)]. / Densitometria ossea a ultrasuoni in età pediatrica: creazione di un database in una popolazione italiana con densitometro multi-sede Omnisense (Sunlight Technologies).

The values of bone density represent one of the best parameters for the prediction of the risk of fracture in the adult. Since the peak of bone mass depends over that on genetic factors also on modifiable environmental factors, the evaluation of the state of bone health in paediatric populations has assumed great importance; the ultrasound techniques seem to represent a potential alternative to DXA and QTC. Using Omnisense device (Omnisense, Sunlight Ultrasound Technologies) we have evaluated the bone strength in a champion of 652 children and teen-agers aged 6-18 (328 females, 324 males). The measurements have been made at the distal third of the radius and midshaft tibia. The purpose has been to record the values of SOS in a healthy paediatric population, building a normal database and to find a correlation between the SOS values and anthropometric data, dietary factors and physical activity. The comparison with an analogous study conducted by other Authors prompted us to conclude that in the paediatric population the construction of proper curves of reference, with which to compare the data of the patients, is essential to avoid errors in the evaluation of bone density, in agreement with how much already underlined in literature. Besides a correct interpretation of the data obtained with ultrasounds systems asks for a change of the thresholds values established by the OMS for the diagnosis of osteopenia/osteoporosis with the DXA. As already happened for the adult population in children also it will be therefore necessary to compare a great number of pathological subjects with the normal database, establishing so the new values of Z-Score and giving a clinical meaning to the effected measurements.

Abomasal nematodes of the red deer Cervus elaphus in north-eastern Italy.

The composition of the abomasal helminth fauna and parasite diversity were studied in 298 red deer collected during 1997-2000 from three different sectors (Bolzano, Trento and Sondrio provinces) of the Stelvio National Park, one of the main protected areas of north-eastern Italy. The association between parasite burdens and geographical areas of the hosts was assessed using the negative binomial regression. A variety of abomasal helminths, both host specific and generalist, was found in all sectors. The most commonly observed parasites were the Spiculopteragia spiculoptera morph spiculoptera and Ostertagia leptospicularis morph leptospicularis, with prevalences of 79.5% and 40.9%, respectively. The minor morphs S. spiculoptera morph mathevossiani (prevalence 31.9%) and O. leptospicularis morph kolchida (18.8%) occurred at lower prevalences. Teladorsagia circumcincta morph circumcincta, Marshallagia marshalli morph marshalli and Haemonchus contortus were rarer, at prevalences of 1, 1.3 and 1.3%, respectively. Deviance analysis of the negative binomial regression model shows that the geographical area is significantly related to parasite burdens (P = 0.001). Prevalences of hosts with parasites were greater in the Sondrio (odds ratio = 1.31; 95% confidence interval: 0.16-10.85) and smaller in the Trento (odds ratio = 0.62; 95% confidence interval: 0.20-1.96) sectors with respect to Bolzano, but these differences were not statistically significant. Possible cross-infections by more generalist parasites between wild and domestic animals were also suggested, as deer and domestic ruminants (Bovinae, Caprinae and Ovinae) used the same feeding areas of the park sectors.

[Association among postural and skull-cervico-mandibular disorders in childhood and adolescence. Analysis of 428 subjects]. / Associazione tra disordini posturali e cranio-cervico-mandibolari in età evolutiva. Analisi di un campione di 428 soggetti.

The aim of the study is to appraise the prevalence of the mild defects of the spine or paramorphysm in a normal paediatric population, without orthopaedic pathology, and to verify the possible association with the dysfunctions of the dental apparatus. The recovery of a real association among these pathologies could furnish a sprout for a correct therapeutic approach. In the study 428 subjects (211 females and 217 males), aged 9 to 14 years, have been analyzed. The data have been recorded on special schedules, orthopaedic and orthodontic, containing the number of progressive order and the initials of name and last name, in the respect of the privacy of the subjects. From the study a 2.8% scoliosis incidence has emerged, an incidence of scoliotic attitudes 9.5% and an incidence of 83% normality deviations. As deviations by the normality have been classified the isolated skeletal asymmetries, agreements as varying functional not yet pathological, for instance scapular or flank asymmetry, mild genu varum or valgum, femoral anteversion. A statistically significant relationship among that disorders of posture and malocclusion (P < 0.005) and ogival palate (P < 0.002) has been found. Despite these correlations, it is very difficult to explain this association from the point of view of etiopathogenesis. For this we hold to have to continue the study, to give a meaning to such correlations and to find an appropriate therapy.

Analysis of imperfect polarizer effects in magnetic rotation spectroscopy.

Small amounts of ellipticity in the nominally linearly polarized light used in magnetic rotation spectroscopy play an important role in determining the character of the signals developed in these experiments. For example, ellipticity introduced by stress-induced birefringence can easily influence such signals more than does a nonzero polarizer extinction ratio. In addition, for nearly-crossed polarizers, an initial ellipticity allows one to probe magnetic circular dichroism instead of the more commonly investigated magnetic circular birefringence. A general expression for the magnetic rotation spectroscopy signal is derived and compared to experimental results. An expression for the detection sensitivity is developed by taking shot noise and rms laser power uctuations to be the dominant noise sources.

Evolution of the concepts of functional anatomy of the knee joint.

It is the purpose of this study to present a review of studies on the kinematics of the knee joint and load distribution in the two compartments, medial and lateral, in order to reveal the evolution of concepts of functional anatomy. Flexion-extension features have been clearly defined by numerous authors who have used different methods of research. Transverse rotation, instead, still needs to be clarified. In particular, whether or not a screw-home movement exists has been questioned by many authors who have studied the kinematics of the knee, both without loading and during walking. Dynamic studies have shown how the radiographic method (static) to deduce load distribution in the knee joint is inadequate; this is because during walking, loading tends to be transmitted on the medial compartment, also the case in valgus knees.

Cardiovascular autonomic modulation in essential hypertension. Effect of tilting.

To better understand the role played by the autonomic nervous system in essential hypertension, we used autoregressive power spectrum analysis to study the noncasual oscillations in RR interval, blood pressure, and skin blood flow in 40 subjects with mild to moderate hypertension and in 25 age-matched control subjects at low frequency (index of sympathetic activity to the heart and the peripheral circulation) and high frequency, respiratory related (index of vagal tone to the heart). RR interval, respiration, noninvasive systolic blood pressure, and skin arteriolar blood flow were simultaneously and continuously recorded with subjects in the supine position and immediately after tilting. The low-frequency component was not significantly different in the two groups either at the cardiac level (control versus hypertensive subjects: 39.1 +/- 4.3 versus 39.9 +/- 3.7 normalized units [NU]) or at the vascular level (1.52 +/- 0.17 versus 1.69 +/- 0.13 ln mm Hg2). After head-up tilting, the RR interval fluctuations were less in hypertensive subjects (low-frequency components from 39.9 +/- 3.7 to 48.4 +/- 4.1 NU, P < .05; high-frequency components from 53.9 +/- 3.7 to 44 +/- 4 NU, P < .05) than in control subjects (low-frequency components from 39.1 +/- 4.3 to 64.4 +/- 4.9 NU, P < .001; high-frequency components from 56.0 +/- 4.5 to 31.2 +/- 4.6 NU, P < .001); the low-frequency components in systolic blood pressure increased similarly in hypertensive subjects (to 2.43 +/- 0.17 ln mm Hg2, P < .0001) and in control subjects (to 2.44 +/- 0.21 ln mm Hg2, P < .01), but the low-frequency components in skin blood flow increased only in control subjects (from 5.34 +/- 0.45 to 6.55 +/- 0.53 mm Hg2, P < .01), not in hypertensive subjects (from 5.55 +/- 0.34 to 5.60 +/- 0.35 ln mm Hg2). In hypertensive subjects with left ventricular hypertrophy, the low-frequency components in systolic blood pressure did not increase after tilting (from 1.75 +/- 0.33 to 2.05 +/- 0.41 ln mm Hg2). Baroreflex sensitivity, as assessed by spectrum analysis, was significantly lower in hypertensive than in control subjects (5.17 +/- 0.49 versus 13.18 +/- 2.44 ms/mm Hg, P < .001. Power spectrum analysis did not reveal an increased sympathetic activity or reactivity either at the cardiac or at the vascular level. The decreased baroreceptor sensitivity in hypertensive subjects could explain the reduced change in sympathovagal balance in the tilt position at the cardiac level. In hypertensive subjects without left ventricular hypertrophy, cardiopulmonary reflex deactivation induced by tilting and/or amplification of sympathetic nervous tone by arteriolar structural change could have preserved the sympathetic activation at the vascular level.

[New therapeutic trends in thalassemia: oral chelating agents]. / Nuove prospettive terapeutiche per la thalassemia: i chelanti orali.

The future therapeutic strategy for decreasing iron overload in poly-transfused patients will include oral chelation. The product currently undergoing the most intensive experimentation is Ll (1,2-dimethyl-3-hydroxypyrid-4-one). We report here a short-term efficacy study carried out in 10 thalassemic transfusion-dependent pediatric volunteer patients, already closely followed in our Day Hospital, after having provided their informed consent. In our study Ll, when compared to Desferrioxamine, was clearly efficacious and safe.

Clinical and radiographic evaluation of the Codivilla method of surgical correction of congenital club foot. Medium-term follow-up of 235 cases.

The authors review 30 patients with congenital club foot (CCF) who were treated surgically by a slightly modified Codivilla technique. Clinical morphologic, and functional follow-up was performed an average of 10 years later, and the findings were compared to the radiographic features. The final outcome was rated good in 41% of the cases, fair in 29%, and unsatisfactory in 30%. The authors found a close correlation between the grade of the initial deformity and the final outcome. Some sign of the deformity always remained, even when the functional outcome was excellent.

Fracture with loss of the proximal femur in a child. A case report.

An 8 year old child was involved in a road accident and sustained a large wound in the left groin; radiographs showed a fracture with loss of the proximal femur. After skeletal traction for 80 days, there was bony regeneration of the proximal femur. At 8 months she was able to walk without support and her left leg was 2 cm only shorter than the right.

Radiographic findings in hereditary multiple exostoses and a new theory of the pathogenesis of exostoses.

Analysis of 330 exostoses in 18 patients affected by hereditary multiple exostoses disease suggested a new classification of exostoses as eccentric or full-thickness. Radiographically arrest of metaphyseal remodeling with failure of coning and persistence of the primary metaphyseal trabeculae was evident in full-thickness exostoses. Similar bone lesions can be obtained experimentally with inhibitors of bone turn-over. A localized, peripheral defect in remodeling over a limited time can give a satisfactory explanation also for the origin of eccentric exostoses. The thesis that this is the basic mechanism of exostosis formation is presented.

An analysis of the changes in the surfaces of metallic femoral components in hip prostheses. A study of 60 prostheses removed after 1-20 years.

A study of 60 femoral prosthetic components removed after 1-20 years allowed us to study the behaviour of the metallic surface in real life conditions. Changes were observed exclusively in cemented prostheses. They consisted of corrosion phenomena characteristic of the components of steel EN 58 J and 316 S, and wear phenomena secondary to mobilisation. The latter were observed in steel components as well as in those in Co-Cr alloy. The areas of corrosion in the steel prostheses were characteristically distributed, indicating a combination of causal factors, including an insufficient capacity of passivation of the metal and the particular situation of the cement-to-metal interface.

[Intraneural synovial cyst of the external sciatic popliteal nerve]. / Kyste synovial intranerveux du nerf sciatique poplité externe.

The authors report a case of an intraneural ganglion of the peroneal nerve. The cystic material was found to expand the neural sheath, while the neural fasciculi were few and atrophic. A communication between the intraneural cyst and the proximal tibio-peroneal joint was demonstrated. An hypothesis for the pathogenetic basis of intraneural ganglia is presented.

Chondrodystrophic dwarfism and multiple malformations in two sisters.

A genetic skeletal dysplasia with dwarfism, scoliosis and multiple skeletal defects was observed in two sisters. Only nine cases with similar features have been reported in the literature.

Evaluation of the neodymium-YAG laser for treatment of ocular opacities.

The Neodymium:YAG Laser was used to find damage thresholds for glass and PMMA IOLs. In addition, optimal cone angles of the laser in regard to laser safety was determined along with consideration of suitability of other laser wavelengths. Lastly, investigation of substitute solutions for optical breakdown compared to vitreous was evaluated.

Carbon dioxide laser beam control for corneal surgery.

Precise control of output power and beam divergence of a CO2 laser resulted in focused beam diameters down to 25 microns and essentially continuous control of energy deposition on target. Application of controlled laser beams on cow, hog, and human eye-bank reject corneal tissue give evidence of well-defined, narrow cuts. The controllable penetration depth and width of the CO2 laser incisions seem to make the laser an ideal "knife" for such corneal modifications as radial keratotomy and epikeratophakia. Our results indicate that the CO2 laser, when successfully integrated with the standard slit lamp, may be a safer and useful tool in laser surgery of the cornea.