Patellar complications (total knee arthroplasty). Effect of lateral release and thickness.

One thousand, one hundred forty-six Anatomic Graduated Component total knee arthroplasties performed between 1987 and 1989 were used to investigate the effects of patellar thickness alone or coupled with lateral retinacular release on initial patellar complications and maximal flexion. Lateral release was found not to be statistically significant regarding radiolucency, patellar prosthesis loosening, or an increase or decrease in flexion. However, total knee arthroplasties in which a lateral release was done, which either saved the superior lateral genicular artery or sacrificed the superior lateral genicular artery, were found to increase the incidence of initial patellar fractures and/or loosening (complications within 1 year) when compared with total knee arthroplasties in which a lateral release was not performed. There was no statistical difference in failure rates regarding fractures and/or loosening of the patella between lateral releases in which the superior lateral genicular artery was saved and the lateral releases in which the superior lateral genicular artery was sacrificed. A difference in postoperative patellar thickness compared with preoperative patellar thickness was found not to be significant to initial patellar fracture and/or loosening, patellar fracture alone, patellar loosening alone, radiolucency, the need for a lateral release, or to an increase or decrease in flexion. Lateral release and patellar thickness had no significant effect on patellar fracture and/or loosening.

Pneumomediastinum in a female track and field athlete: a case report.

OBJECTIVE: To present the case of an elite female track and field athlete who suffered a pneumomediastinum resulting from a Valsalva maneuver performed while throwing the javelin. BACKGROUND: Episodes of chest pain and labored breathing in athletes may be alarming. Accurate, early diagnosis is enhanced by an awareness of those relatively rare conditions that may cause these symptoms. DIFFERENTIAL DIAGNOSIS: Bronchial injury/fracture, retropharyngeal abscess, acute pulmonary disease, pneumomediastinum, pneumothorax, cardiac disease, allergic reaction. TREATMENT: The athlete was given intravenous morphine for pain, prescribed oral pain medication, and restricted from strenuous activity for 6 weeks. Aerobic exercise was allowed after pain and air in the neck subsided, which was estimated at 1 week postinjury. UNIQUENESS: This is a rarely reported case of a pneumomediastinum in a female and a track and field athlete. CONCLUSIONS: Medical personnel must be aware of the possibility of pneumomediastinum in track and field athletes and in female athletes and must be knowledgeable in the followup care and the safe return of the athlete to activity.

Efficiency of human rotavirus propagation in cell culture.

This study was designed to find methods to reproducibly propagate human rotaviruses from fecal specimens and to determine the relationship between particle numbers and infectivity. Growth of virus was initially compared in primary and continuous lines of monkey kidney cells. Primary cells (African green and cynomolgus monkey kidney) supported virus growth directly from fecal specimens much more efficiently than did continuous lines of African green (CV-1) or rhesus (MA104) monkey kidney cells. Rotaviruses were grown in primary cells from 14 of 14 fecal specimens of different individuals collected over a 3-year period. Although rotaviruses in fecal samples could not always be grown in the continuous cell lines, two passages in primary cells appeared to fully adapt the viruses for propagation in the continuous cell line tested (MA104). The efficiency of rotavirus growth was quantified with five of the fecal isolates. It was calculated that, on the average, 1 out of every 46,000 particles in fecal specimens infected monkey kidney cells. After three passages in primary cells, an average of 1 out of every 6,600 progeny virus particles appeared to be infectious. Thus, rotaviruses in fecal specimens were consistently grown in primary cells, and passage in these cells both increased virus infectivity and adapted the viruses for growth in continuous cell lines.