Irreducible intertrochanteric fractures of the femur.

A retrospective study during a 3-year interval revealed that four of 112 patients had intertrochanteric fractures that were irreducible by the usual closed manipulation and traction techniques at the time of surgery. Each of these patients' preoperative radiographs showed a fracture line that bisected the lesser trochanter and was relatively uncomminuted. Although longitudinal traction and appropriate closed manipulation provide acceptable reduction for most intertrochanteric fractures, the few with the described fracture pattern may require open reduction with removal of interposed soft tissue to achieve satisfactory alignment.

A biomechanical comparison of cervical laminaplasty and cervical laminectomy with progressive facetectomy.

The effects of multilevel cervical laminaplasty and laminectomy with increasing amounts of facetectomy on stability of the cervical spine were tested with physiologic loading in nine cadaveric specimens. Cervical spines, levels C2-C7, were tested with physiologic loading in a constraint-free test system, the motion of each body being tracked in a three-dimensional coordinate system. Cervical laminectomy with 25% or more facetectomy resulted in a highly significant increase in cervical motion compared to the intact specimens for the dominant motions of flexion/extension (P < 0.003), axial torsion (P < 0.001), and lateral bending (P < 0.001). Cervical laminaplasty was not significantly different from the intact control, except for a marginal increase in axial torsion. Coupled motion did not change with laminaplasty or laminectomy with progressive facetectomy. As little as 25% facetectomy adversely affects stability after multilevel cervical laminectomy. Cervical laminaplasty avoids this problem, while still affording multilevel decompression. Therefore in patients undergoing cervical laminectomy accompanied by more than 25% bilateral facetectomy, concurrent arthrodesis should be performed.

The frequency of aneuploidy in cultured lymphocytes is correlated with age and gender but not with reproductive history.

The clinical significance of low numbers of aneuploid cells in routine cytogenetic studies of cultured lymphocytes is not always clear. We compared the frequencies of chromosome loss and gain among five groups of subjects whose karyotypes were otherwise normal; these groups were (1) subjects studied because of multiple miscarriages, (2) parents of live borns with autosomal trisomy, (3) subjects studied because they had a relative with Down syndrome, (4) an age-matched control group of phenotypically normal adults studied for other reasons (e.g., parent of a dysmorphic child or member of a translocation family), and (5) other mostly younger and phenotypically abnormal subjects who could not be assigned to the first four groups (e.g., individuals with multiple congenital anomalies or mental retardation). No significant age, sex, or group effects were observed for autosomal loss (hypodiploidy) or gain (hyperdiploidy). Autosomal loss was inversely correlated with relative chromosome length, but autosomal gain was not. Sex-chromosome gain was significantly more frequent in females than in males, but sex-chromosome loss was not significantly different between the sexes. Significant age effects were observed for both gain and loss of sex chromosomes. When age and sex were accounted for, the frequencies of sex-chromosome loss and gain were not significantly different among the five clinical groups. In general, low numbers of aneuploid cells are not clinically important when observed in blood chromosome preparations of subjects studied because of multiple miscarriages or a family history of autosomal trisomy.