ABSTRACT
OBJECTIVE@#To provide reference of the ideal entry point for antegrade femoral nailing according to analysis correlation between highest point of greater trochanter and the middle line of the medullary cavity in adults by three-dimensional images.@*METHODS@#From January 2016 to January 2017, 107 adults who underwent continuous computed tomography (CT) scans were ultimately enrolled, including 64 males and 43 females with an average age of (51.7±16.4) years old;54 patients on the left side and 53 patients on the right side. Three-dimensional images were built by using image-processing software (Volume Viewer) to reconstruct geometry of cortex and medullary canal. All people weregrouped according to different femoral greater trochanter morphology, such as anterior apex (AA), posterior apex (PA), middle apex (MA) and none apex (NA). Forwards inclination was adjusted to apparent neck shaft angle (ANSA) and true neck shaft angle (TNSA) on the coronal and saggittal view, recorded as C-ANSA, C-TNSA, S-ANSA, S-TNSA respectively, vertical distance from the middle line of femur medullary cavity to the highest point of greater trochanter of femur on the 4 positions were measured and performed statistical analysis, multiple linear regression was applied to analysis relationship between clinical data and VD value.@*RESULTS@#(1)Comparison of VD value among 4 groups on the 4 positions, there were no difference in VD value between AA and MA groups on the S-ANSA position;and no differences in VD value among AA, MA and NA groups on the C-ANSA and C-TNSA position. (2)There were differences in VD value among AA, MA and NA groups on the sagittal plane;while had difference in VD value between PA and NA group on the coronal plane. (3)Prediction equation of VD value on S-ANSA and S-TNSA position by multiple linear regression showed R=0.343, F=3.409, =0.012 on the S-ANSA position;R=0.317, F=2.846, =0.028 on the S-TNSA position; neck shaft angle and sex were risk factors of VD value on the sagittal plane, while no difference in VD value on the coronal position.@*CONCLUSION@#(1)When indentify insertion point in adult femoral nail according to the highest point of greater trochanter as anatomic landmark, the morphology of greater trochanter of femur should be distinguished to certain observation position, then evaluate migration before and after on the sagttial plane and lateral offset on the coronal plane. (2)Migration before and after on the sagttial plane is increase with increase of neck shaft angle, and the degree of migration of female before and after is less than that of male.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Femur , Fracture Fixation, Intramedullary , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Tomography, X-Ray ComputedABSTRACT
Taking the Quercus liaotungensis middle-aged forests in Huanglong and Qiaoshan Mountains as study objects, the average size of individual trees of Q. liaotungensis, yield and rate of its reproductive modules, as well as their spatial distribution characteristics were investigated in five years after thinning at different intensities (CK, 10%, 20% and 30%), in order to demonstrate the impact of thinning intensity on reproductive modules of Q. liaotungensis. Thinning intensity had no significant effect on average height and average DBH, while it had significant positive correlation with crown area and crown volume. The yield of generative shoots, young fruits and mature fruits increased with thinning intensity, but vegetative shoots, staminate inflorescence, staminate flowers and pistillate flowers of Q. liaotungensis had little change. The yield of generative shoots, young fruits and mature fruits had raised significantly under 20% thinning, and reached the maximum under 30% thinning intensity. The rate of generative shoots and fruit setting rate increased with thinning intensity, and reached significant level under 20% or 30% thinning compared with the control. About three-quarters of the generative shoots, female and male flowers centered in the upper canopy, and the rest were in the lower part. Numbers of reproductive modules at sunny side accounted for about 65% of the total. The lower crown, shaded generative shoots, pistillate flowers and staminate inflorescence increased with the increasing thinning intensity, and the upper crown, sunny generative shoots, pistillate flowers and staminate inflorescence showed a decreasing trend with the increasing thinning intensity. Thinning at the intensity of 30% (canopy density 0.6) was the best, which could greatly improve the fruit set percentage of Q. liaotungensis and its mature rate, so as to improve the seed yield and quality, providing the guarantee for the seed collection and natural regeneration of Q. liaotungensis forests.
