Biomechanical Comparison of Different External Fixation Configurations for Posttraumatic Pelvic Ring Instability
Simon TizianiGeorg OsterhoffStephen J. FergusonGregor SpreiterMax J. ScheyererGian-Leza SpinasGuido A. WannerHans‐Peter SimmenClément M. L. Werner
6
Citation
31
Reference
10
Related Paper
Citation Trend
Abstract:
Background . External fixation is useful in the primary treatment of pelvic ring injuries. The present study compared the biomechanical stability of five different configurations of an external pelvic ring fixation system. Methods . Five configurations of an anterior external pelvic ring fixation system were tested using a universal testing machine. One single connecting rod was used in group “SINGLE,” two parallel connecting rods in group “DOUBLE,” two and four rods, respectively, in a tent-like configuration in groups “SINGLE TENT” and “DOUBLE TENT,” and a rhomboid-like configuration in group “RHOMBOID.” Each specimen was subjected to a total of 2000 consecutive cyclic loadings at 1 Hz lateral compression/distraction (±50 N) and torque (±0.5 Nm) loading alternating every 200 cycles. Translational and rotational stiffness were determined at 100, 300, 500, 700, and 900 cycles. Results . The “SINGLE TENT” and “RHOMBOID” configurations already failed with a preloading of 50 N compression force. The “DOUBLE” configuration had around twice the translational stability compared with the “SINGLE” and “DOUBLE TENT” configurations. Rotational stiffness observed for the “DOUBLE” and “DOUBLE TENT” configurations was about 50% higher compared to the SINGLE configuration. Conclusion . Using two parallel connecting rods provides the highest translational and rotational stability.Keywords:
Rod
Cage
Cage
John Cage
Cite
Citations (0)
This study was carried out to determine the effects of genotype, cage density and position on the pullet performance of commercial layer chicks housed in cages. Two thousand 1-day-old chicks of Lohman Brown, Lohman White, Isa Brown and Bowans White genotype were housed at 3 cage densities (105.9, 134.8, 185.3 cm 2
Cage
White (mutation)
Cite
Citations (10)
Two experiments were conducted to study the effects of number of nipple waterers (NW) per four-bird, deep cage (30.5 × 45.7 cm deep) or shallow cage of exact reverse dimensions and location of these waterers on productivity of commercial strain of White Leghorn layers reared in floor pens equipped with either dome or trigger cup waterers. The pullets were housed in laying cages at 18 wk of age. In both experiments, cage shape had no significant effects on the variables measured. Location of NW effects varied between experiments; hens incages with NW located in the front of the cage had a significantly (P<.05) lower rate of lay (1.7%) in Experiment 2 and less mortality (5.4%) in Experiment 1 than those in cages with NW located in the rear. Location of NW had a NS effect on water consumption in both experiments. Number of NW per cage significantly (P<.05) affected water consumption in both experiments. Hens in cages with two NW consumed 32.5 and 36.7 mL/hen day more water in Experiment 1 and 2, respectively, than those in cages with one NW.
Cage
Collar
Laying
Cite
Citations (6)
Two groups of White Leghorn pullets, reared in floor pens, were observed for changes in behavioral traits when housed in cages. Data in Experiment 1 were obtained during Days 1 to 5 posthousing from 40 pullets kept in eight 40.7-cm wide × 45.7-cm deep cages with either four or six birds/cage and in Experiment 2 during Days 1 to 5 and Day 7 posthousing from 24 pullets housed four/cage in three 30.5-cm wide × 45.7-cm deep cages (deep cages), and three 45.7-cm wide × 30.5-cm deep cages (shallow cages). In Experiment 1, pullets housed four/cage spent significantly (P<.05) fewer periods standing and crouching, but more periods preening, feeding, and performing comfort movements, than those housed six/cage. There was a significant group size × days posthousing interaction for standing and drinking. Standing was most frequent in the four-hen cages on Day 1 and then declined, whereas periods of standing increased in six-bird cages. Drinking behaviors were significantly different only on Day 1; six birds per cage had the lowest level. In Experiment 2, pullets in deep cages spent significantly more periods standing and moving and fewer periods crouching. Crouching frequencies declined from Day 1 to Day 7 posthousing for birds in both deep and shallow cages. Although there were significant cage shape × days posthousing interactions for all behavior observed, the interactions appeared to be associated with erratic day-to-day differences between hens in deep and shallow cages.
Cage
Cite
Citations (19)
Experiment 1 compared the effects of cage shape, feeder space, and bird density on performance, nervousness, and feathering of two commercial Single Comb White Leghorn (SCWL) strains. Strain 1 bird s and those housed 3 per cage produced more eggs with fewer body checks and cracks, tended to be less nervous, and had better feather cover than strain 2 birds and those housed 4 per cage (P<.05). Experiment 2 compared the effects of cage shape, feeder space, cage barrier, and bird density on performance of a commercial SCWL strain. Hens in cages with 3 birds laid at 5.4% higher rate (HH) and produced 2.8% fewer undergrade eggs than hens housed 4 per cage (P<.05).
Cage
Strain (injury)
Cite
Citations (71)
INTRODUCTION ALTHOUGH a number of reports have been published which compare the performance of layers on litter floors with that of caged layers, there is a paucity of research literature on the effects of cage density on performance. A number of popular press reports on cage density are available, however. Schupe and Quisenberry (1961) compared the performance of individually caged birds with that of colony caged birds (25 females per cage). Significant differences in egg production and mortality in favor of the individually caged birds were found. Lowe and Heywang (1964) housed females under four cage regimes: (1) individually in 8″ × 18″ cages; (2) individually in 10″ × 18″ cages; (3) two females in 12″ × 18″ cages; and (4) five females in 24″ × 18″ cages, each regime of which was in a separate house. Square inches of floor space per female were not equalized in the various . . .
Cage
Litter
Cite
Citations (11)
1. Pullets (Ross Rangers) reared commercially either in cages or on deep litter were tested for their responses to small (0.38 × 0.43 m) and large (0.76 x 0.86 m) cages with wire floors and to small and large cages with litter floors. 2. When tested at 29 weeks of age, the birds' responses were significantly affected both by cage size (large preferred to small) and by flooring (litter preferred to wire). 3. No difference in cage preference was apparent between cage‐reared and litter‐reared birds either when they were first tested at 17 weeks or when they were re‐tested at 29 weeks. Birds do not have to be reared on litter in order to be attracted by it.
Cage
Litter
Cite
Citations (28)
Two experiments, one with a commercial strain and one with an experimental strain of Single Comb White Leghorns, compared the effects of cage shape, feeder space, cage barrier, bird density, level of feeding, and period observed on feeding behavior and bird movement. In Experiment 1, only period observed significantly affected time spent feeding; the commercial strain of hens generally ate more in the p.m. (1700 to 1900 hr) than in the a.m. (0700 to 0900 hr). A significant (P<.05) feeder-space × period observed interaction indicated that increased feeder space is important in reducing feeder competition during peak feeding times. Only feed consumption of the experimental strain was significantly (P<.05) affected by bird density; hens housed 2 birds per cage ate 10.5 g per hen per day more than those housed 3 per cage (Experiment 2). Birds spent 38. 4 sec more eating during 0600 to 0700 hr than 1700 to 1800 hr (P<.05). Maximum number of birds feeding simultaneously was significantly (P<.05) affected by feeder space, bird density, and level of feeding. Hens with 45.7 cm of feeder space per cage, housed 3 per cage and receiving 90% of full feed had more simultaneous feeding than hens with 25.4 cm of feeder space, housed 2 per cage and on full feed. Hens in deep cages had significantly (P<.05) more quadrant-to-quadrant moves than hens in shallow cages.
Cage
Cite
Citations (14)
This study was conducted to determine the effects of different cage densities on laying performance of white and brown hybrid layers during high summer temperatures. White layers, 68 weeks of age, were housed at a density of 3, 4 or 5 hens/cage (respectively 640, 480 and 384 cm2/hen); brown layers were housed at 3 or 4 hens/cage (respectively 640 and 480 cm2/hen). The results indicated that housing at 3 or 4 hens/cage did not affect egg production or egg quality significantly. Increasing the cage density to 5 hens/cage in white layers decreased egg production and Haugh Units. However, it was observed that shell quality and egg weight were not affected significantly by higher cage density.
Cage
Laying
Cite
Citations (8)