The rotator cuff-deficient arthritic shoulder: diagnosis and surgical management.

The symptomatic rotator cuff-deficient, arthritic glenohumeral joint poses a complex problem for the orthopaedic surgeon. Surgical management can be facilitated by classifying the disorder in one of three diagnostic categories: (1) rotator cuff-tear arthropathy, (2) rheumatoid arthritic shoulder with cuff deficiency, or (3) degenerative arthritic (osteoarthritic) shoulder with cuff deficiency. If it is not possible to repair the cuff defect, surgical management may include prosthetic arthroplasty, with the recognition that only limited goals are attainable, particularly with respect to strength and active motion. Glenohumeral arthrodesis is a salvage procedure when other surgical measures have failed. Arthrodesis is also indicated in patients with deltoid muscle deficiency. Humeral hemiarthroplasty avoids the complications of glenoid loosening and is an attractive alternative to arthrodesis, resection arthroplasty, and total shoulder arthroplasty. The functionally intact coracoacromial arch should be preserved to reduce the risk of anterosuperior subluxation. Care should be taken not to "overstuff" the gleno-humeral joint with a prosthetic component. In cases of significant internal rotation contracture, subscapularis lengthening is necessary to restore anterior and posterior rotator cuff balance. If the less stringent criteria of Neer's "limited goals" rehabilitation are followed, approximately 80% to 90% of patients treated with humeral hemiarthroplasty can have satisfactory results.

Oral ciprofloxacin compared with standard parenteral antibiotic therapy for chronic osteomyelitis in adults.

A group of fourteen patients who had chronic osteomyelitis and were treated with oral ciprofloxacin was compared with a group of twelve patients of similar age who had chronic osteomyelitis and received standard parenteral antibiotic therapy consisting of nafcillin, clindamycin, and gentamicin, singly or in combination. The osteomyelitis was arrested at the end of therapy and on follow-up examination of eleven patients in the first group and ten in the second group. The average duration of antibiotic therapy (thirty-eight days) and follow-up (approximately thirty months) were about the same for both groups. Oral administration of ciprofloxacin was as effective and safe as parenteral therapy for the treatment of osteomyelitis in these adults.

Lateral tibial plateau fracture as a postoperative complication of high tibial osteotomy.

Fractures associated with valgus producing high tibial osteotomy are generally reported as operative complications which involve the medial proximal segment. Factors associated with this fracture at the time of surgery include forceful closure of the osteotomy after an inadequately perforated medial cortex, a proximal segment being less than 1.5cm in thickness, and osteotomes entering the medial compartment due to excessive bone loss. Three patients are reported with postoperative fracture of the lateral tibial plateau after tibial osteotomy. One patient's fracture was clearly due to trauma and the other two occurred in patients with a thin proximal segment.

Molecular structures of 5,6- and 7,8-benzoflavones, inhibitors of aryl hydrocarbon hydroxylase.

The crystal and molecular structures of two isomeric inhibitors of carcinogenesis by certain polycyclic aromatic hydrocarbons are described. The two compounds are 7,8-benzoflavone and 5,6-benzoflavone, which are shown by X-ray crystallographic studies to differ appreciably in their three-dimensional structures. Polycyclic aromatic hydrocarbons are metabolically activated by an enzyme system that is responsibe for the detoxification of many chemicals that enter the body. The two benzoflavones described here differ in their effect towards specific enzymes in the metabolizing system. Potential energy calculations predict that a nonplanar conformation is most probable for these flavone derivatives, as a result of the presence of a biphenyl-like system. Such a conformation is found for 7,8-benzoflavone with a torsion angle of 23 degrees between the phenyl group and the rest of the molecule. The isomeric 5,6-benzoflavone is, in contrast, found to be a predominantly flat molecule. There is an interaction between O(4) and a neighboring -C-H group which may explain the planarity of 5,6-benzoflavone. A comparison is made with structures of some common carcinogenic polycyclic aromatic hydrocarbons, the activities of which these two benzoflavones inhibit.

Boron modifications produced in an induction-coupled argon plasma.

Most of the small particles (50 to 100 micrometers in diameter) of microcrystalline beta-rhombohedral boron that quickly transit an argon plasma maintained within a radio-frequency induction-coupled torch emerge as better crystallized spheroids of the same crystalline form and nearly the same size as the starting material. A few crystals of each of four distinctive, well-faceted habits are formed along with the general product. Three of these types are monocrystals of the beta-rhombohedral polymorph, of the tetragonal-III modification, and of an unreported cubic form of boron. Specimens of the fourth type are polycrystals of another unreported form of boron, apparently consisting of many hexagonal platelets stacked in an imprecise fashion.