Fabellar prevalence, degeneration and association with knee osteoarthritis in the Chinese population

The fabella is a sesamoid bone of the knee that can degenerate in some patients with osteoarthritis. The purpose of this study was to examine the prevalence and degeneration grades of fabellae in the Chinese population and to analyse their relationships with subject ages and knee osteoarthritis grades. The anteroposterior and lateral knee roentgenograms of 1150 subjects were recruited from the institutional database. The Kellgren-Lawrence scoring system was used to evaluate knee osteoarthritis. The degeneration grades of fabellae were scored in lateral roentgenograms by screening their shapes, sizes, subchondral sclerosis and osteophyte formation. The prevalence and degeneration of fabellae among ages, genders and knee sides were analysed by the Pearson Chi-Square test, and their relationships with knee osteoarthritis were analysed by the Spearman nonparametric correlation test. The overall prevalence of fabellae was 48.6% in 1359 knees. There was no significant difference in fabellar prevalence between the two sides (χ² = 0.025, P = 0.87437) and genders (χ² = 3.647, P = 0.05617), while the prevalence increased with the increasing ages of the subjects (χ² = 213.868, P < 0.001). The fabellar degeneration grades were correlated with age (r = 0.5288, P < 0.001) and knee osteoarthritis scores (r = 0.6892, P < 0.001). These results suggested that the fabellar prevalence and degeneration grades were correlated with age and knee osteoarthritis scores.

A Comparative Study of the Frequency of Anterior Impingement Exostoses of the Ankle in Dancers and Nondancers

True lateral roentgenograms were obtained in 100 nondancers and 32 professional dancers to determine the incidence of anterior talar exostoses. The average age of the nondancers was 45.8 years as compared to 23.0 years in the dancer population. Both groups were asymptomatic in the region of the foot and ankle. All exostoses on the dorsum of the talar neck measuring greater than 1 mm were recorded.

Computer-assisted Stereotactic Laser Microsurgery for the Treatment of Intracranial Neoplasms

This paper describes a stereotactic CO2 laser system for the removal of intra-axial, intracranial neoplasms. The volume of the neoplasm is transferred into stereotactic space by computer reconstruction of data derived by computed tomography (CT) performed under stereotactic conditions. The tumor volume is sliced in a plane orthogonal to the surgical approach, and slices at specific distances from the focal point of the stereotactic frame are displayed on a graphics monitor in the operating suite along with a cursor representing the position of the surgical laser. Laser vaporization of sequential slices of the tumor results in a cavity, the formation of which is monitored by anteroposterior and lateral roentgenograms. Fifteen stereotactic laser procedures have been performed on 13 patients, and the results are discussed. By this method, it is theoretically possible to remove all of an intracranial neoplasm detected by CT scanning.

In vivo dimensional response of airways of different size to transpulmonary pressure

We studied four supine dogs that were anesthetized with pentobarbital, intubated, and ventilated with a piston pump. The dimensional response of central (CAW) (greater than 2 mm diam) and peripheral airways (PAW) (smaller than 2 mm diam) to changes in transpulmonary pressure (Ptp) was determined by progressive increments in tidal volume (VT). A specially designed electronics relay circuit permitted this relationship to be obtained for points of no flow during tidal volume breathing: i.e., preinspiration (FRC); end inspiration (FRC + VT). The airways were dusted with powdered tantalum. Six airway divisions were identified: four CAW: trachea, main stem, lobar, segmental; and two PAW: subsegmental, and lobular. AP and lateral roentgenograms were obtained by standard technics and primary magnification (mag factor 2). Airway diameters were plotted as a function of transpulmonary pressure between 3 and 26 cmH2O with the diameter at total lung capacity expressed as 100%. The data show that: 1) there is significant distensibility above 5 cmH2O for all airways from the trachea to the lobular airways; 2) that the pressure-diameter plot is a linear plot for each airway from 3 to 26 cmH2O with R values between 0.846 and 0.957; 3) the peripheral lobular airways are more distensible than the central airways (P smaller than 0.05). We attribute the difference in distensibility of the peripheral lobular airways to their lack of cartilaginous support, and their decreased muscular support when compared to the CAW.

PROPER LOCALIZATION OF UMBILICAL ARTERIAL AND VENOUS CATHETERS BY LATERAL ROENTGENOGRAMS

Widespread use of umbilical arterial and venous catheters to monitor the acid-base status of sick newborn infants has made proper placement of such catheters mandatory. Clinical assessment of their placement is poor. Radiographic localization is simple with anteroposterior and most important lateral films of the chest and abdomen. The venous and arterial course is totally different since the vein ascends anteriorly, while the artery descends to join the pelvic arteries before a posterior ascent into the aorta. The lateral film is optimal to identify inadvertent venous catheterization of a mesenteric vein or a wedged portal vein site. The lateral arterial view allows correction should the catheter slip into the ductus arteriosus and pulmonary arteries. The arterial catheter placement is felt to be best situated either in the chest below the ductus or in the abdomen below the major arteries to avoid either irritation of their ostia or injection of highly alkaline agents into the kidneys or intestines.