Health care trends lead to specialization of the MBA.

Four authors associated with St. Thomas University, John G. Reiling, M.B.A., John W. LaBree, M.D., Frederick J. "Fritz" Wenzel, FACMPE, and Carl Platou, M.B.A., write about how the changing nature of health care has fostered the need for a specialized Master of Business Administration in Medical Group Management degree program.

Effect of immobilization of short duration on the muscle fibre size.

In 10 patients with unilateral knee joint lesions, the injured leg was immobilized for 72 h by a plaster cast reaching from the hip to the ankle. At removal of the casts, open muscle biopsies were taken from the vastus medialis muscle on both sides. The muscle specimens were stained for myofibrillar ATPase activity and muscle fibre areas were measured on transverse sections. The differences in fibre size between the two sides were registered and statistically evaluated. The reduction in fibre size on the immobilized side was 14.4% for the type 1 fibres and 17.3% for the type 2 fibres, respectively. However, these differences were not significant because of considerable variations from case to case, with an increase in fibre size on the immobilized side in three cases. It is concluded that short time post-traumatic immobilization may have variable effects on the muscle fibre size and that one single biopsy might be insufficient to disclose early disuse atrophy whereas the method may be useful in cases of longer duration.

Incisor position in Scandinavian children with ideal occlusion. A comparison with the Ricketts and Steiner standards.

A cephalometric study, with particular emphasis on incisor pattern, was carried out on thirty Norwegian children with clinically excellent occlusion in the young permanent dentition. The material was selected from a sample of all 12-year-old children within a particular geographic area (Nittedal) of Oslo. The frequency of ideal occlusion was 5.3 percent. A computer-based method of cephalometric analysis was used. The findings indicated that persons with untreated ideal occlusion tended to have a particular facial morphology and dental pattern. More precisely, they were likely to be brachyfacial (horizontal), with somewhat procumbent incisors and a small interincisal angle. Only one patient had dolichofacial (high-angle) characteristics. On average, the lower incisors were 2.5 mm. in front of the APo plane (S.D. 1.7). Remarkably, the lower incisors were not behind the APo plane in any single case with ideal occlusion. Clearly, the lower incisors were clinically significantly more protruded and proclined than those described in previous studies on Scandinavian children and were, in fact, even slightly more procumbent than the Ricketts and Steiner standards. The similarity, with regard to both incisor position and skeletal pattern, of the present findings to some recent studies on American Caucasian children with normal occlusion is stressed. The significance of the observations is discussed in relationship to considerations in orthodontic treatment planning.

Disuse atrophy of human skeletal muscle. An enzyme histochemical study.

The effect of inactivity was examined in muscle biopsies from ten patients who were operated upon for unilateral knee joint lesions of long duration. Biopsies were taken from the vastus medialis on both sides, and transverse frozen sections were stained for myofibrillar adenosine triphosphatase (ATPase). Fibre type counting and exact measurements of muscle fibre size were performed and compared on the two sides. The muscle fibres on the affected side showed a definite reduction in size and, on the average, both types of fibres were about equally affected (27.6% vs. 25.0% reduction for types 1 and 2). However, there were considerable and unpredictable variations from case to case with predominant affection of type 1 in some and type 2 in others. The numerical distribution of fibre types did not change. It is concluded that both fibre types are affected in disuse atrophy, but it seems impossible to predict which of the fibre types will show the most severe atrophy. Thus, enzyme histochemical staining methods are of little help in the diagnosis of disuse atrophy.