Interpretation of correlations between nuclear observables in rare-earth nuclei.

We have recently obtained the optimal core-cluster decompositions for an extensive set of heavy even-even nuclei in the rare-earth region. The core-cluster charge products thus deduced are found to be closely correlated with the corresponding B(E2) values. We investigate here the strong resemblance of these correlations to the corresponding Casten plots, and find that the cluster model also predicts a further correlation between core-cluster charge products and the nuclear excitation energies, suggesting a new form of Casten plot for these energies.

Patellofemoral imaging.

Imaging of the patella and patellofemoral joint cannot be isolated from imaging of the knee anymore than the function of the patellofemoral joint can be separated from the function of the entire knee. Therefore, the current author will focus on imaging of the patellofemoral joint yet integrate this with the entire knee. Because radiographs and other imaging techniques are adjuncts to the history and physical examination, and specifically an extension of the physical examination, each view or technique must be selected thoughtfully to yield the most useful and accurate information possible. Imaging techniques range from relatively inexpensive to very costly, yet the amount of useful information may not show a positive correlation with the cost. Only by integrating the history, physical examination, and the best imaging techniques can the clinician locate the abnormality, determine its cause, and plan a proper course of treatment. Radiographic imaging of the patellofemoral joint requires attention to detail on the part of the technician and knowledge of these techniques on the part of the clinician who orders and interprets the results. Understanding these concepts will help achieve everyone's goal: high-quality and cost-effective orthopaedic care.

Classification of patellofemoral disorders.

Patellofemoral disorders represent a large portion of the average orthopedist's practice. Despite the improvements in patellofemoral radiographs and arthroscopic diagnostic techniques, these disorders are too frequently misunderstood and frustrating to treat. This report proposes a clinical classification for patellofemoral disorders that, it is hoped, will aid our understanding and improve our results of treatment. A major feature of this classification is the recognition that a developmental and familial abnormality, patellofemoral dysplasia, is the etiology for most patellofemoral disorders. Equally important is the assignment of chondromalacia patellae to a secondary position for the most part. Other causes of anterior knee pain and disability are included to complete the classification.