The locked flexible intramedullary humerus nail in pediatric femur and tibia shaft fractures: a feasibility study.

There are several options for the treatment of long bone fractures in skeletally immature patients. Surgeon experience, type of fracture, and the possibility of damage to the physeal area dictate individual fracture management patterns. Notably, nail devices have not gained popularity in this patient group. Intramedullary locking nails have become the standard of care in adult patients due to decreased morbidity and mortality. A novel nail has been developed for humeral shaft fractures that uses a lateral starting position to avoid damage to the rotator cuff in humeral fracture fixation. This is possible because of the nail's transient flexibility during insertion. This study illustrates that it is feasible to insert this type of nail through multiple entry portals for both tibial and femoral fracture fixation, without damaging the physeal blood supply or growth areas.

Intermediate follow-up of a simple method of hip arthrodesis in adolescent patients.

Thirteen male patients (average age, 15.6 years) underwent intraarticular hip arthrodesis for unilateral disabling hip disease. Follow-up averaged 6.6 years. Seven patients had excellent or good Harris hip scores. Ten patients had low back pain, and seven patients had knee pain on the side of the fused hip. Limb-length discrepancy averaged 3.7 cm. A progressive hip adduction drift (average, 7 degrees) occurred during follow-up. Patients whose hips were fused in a position of 20-25 degrees flexion and whose limb-length discrepancies were < 2 cm had significantly lower incidences of back pain. Cybex muscle testing revealed significantly decreased quadriceps strength (29%) on the hip-fusion side. Gait laboratory analysis demonstrated decreased velocity, stride length, and cadence. There were two mildly symptomatic nonunions. Based on these results, we recommend that the hip fusion be positioned in 20 degrees flexion and 0 degree abduction. The joint must be completely debrided down to viable bone to maximize chances for union. Maintaining a limb-length discrepancy of < 2 cm is essential to minimize the incidence of low back pain, quadriceps deficiency, and abnormal gait parameters.

Uterine and ovarian artery blood flow in the pregnant dog. Attempt at comparative study in pregnant women.

UABF and OABF were measured in dogs with the electromagnetic flowmeter. In eight nonpregnant animals, UABF was on the average 3.2 ml/min and OABF 0.4 ml/min. In 10 pregnant bitches near term UABF was 27.3 ml/min and OABF 1.3 ml/min. Complete aortic occlusion in the pregnant bitch at term reduces UABF to 2.4 ml/min (loss of 24.9 ml/min) and increases OABF to only 1.6 ml/min (gain of 0.3 ml/min). The conclusion is that most of the blood flow to the uteroplacental unit in the pregnant bitch is channelled through the uterine artery and the marked drop in UABF produced by acute aortic occlusion is not compensated by an increase in OABF. The conditions are different in human pregnancy where the progressive nature of the aortic compression by the pregnant uterus allows, under the most favorable circumstances, the gradual development of a collateral circulation mostly through the ovarian arteries. However, this does not occur all the time as demonstrated by angiographic studies in a series of 12 patients and in similar studies reported in the literature. This could result in a placental insufficiency.