Comparison of the clinical efficacy of different fixation systems for the treatment of transverse patellar fractures.

PURPOSE: This study was designed to compare the clinical efficacy of "8" and "0" wire fixation systems combined with double-head cannulated compression screws or Kirschner wires for the treatment of transverse patellar fractures. METHODS: From September 2011 to September 2018, patients with closed transverse patellar fractures treated with a double-head compression screw or Kirschner wire were included and analyzed retrospectively. Patients with patellar fractures combined with distal femoral fractures, tibial plateau fracture or preoperative lower limb dysfunction were excluded. The patients treated with the "8" tension band wire fixation system and Kirschner wire were taken as Group A; those treated with the "0" fixation system and Kirschner wire were taken as Group B; those treated with the "8" fixation system and double-head cannulated compression screw were taken as group C; and those treated with the "0" fixation system and double-head cannulated compression screw were taken as group D. Six weeks and one year after the operation and every month from the third month after the operation until the fractures healed, an X-ray examination was performed to identify fracture healing. The time of fracture healing and postoperative complications of the four groups were compared. One year after the operation, knee function was evaluated by Bostman's score. RESULTS: During the study period, 168 patients with patellar fractures were treated by operations, and 88 patients were excluded because the fracture type did not meet the requirements or because there were combined fractures of the distal femur or tibial plateau. As a result, 80 patients were included in this study, 20 in each group. All the patients were followed up for an average period of 12.2 months. Compared with Group A, patients in Group D presented less postoperative discomfort in the prepatellar region, quicker fracture healing, less fixation failure and better postoperative knee function scores (all p < 0.05). The incidence of internal fixation failure in Group (B+D) was lower than that in Group (A+C) (p > 0.05). CONCLUSION: The "0" wire fixation system combined with a double-head cannulated compression screw seems to be more beneficial than the other three fixation systems for the treatment of transverse patellar fractures.

Oxacalix[4]arene-bridged pillar[5]arene dimers: syntheses, planar chirality and construction of chiral rotaxanes.

Conformationally fixed oxacalix[4]arene-bridged pillar[5]arene dimers comprising a pair of enantiomers and a meso isomer were designed and synthesized. Furthermore, chiral [2]rotaxanes and [3]rotaxanes were constructed. Two pairs of enantiomers for [2]rotaxanes, one pair of enantiomers and a meso isomer for [3]rotaxanes were found, respectively.

Histopathologic study of the neuroma-in-continuity in obstetric brachial plexus palsy.

BACKGROUND: Operative treatment of traction lesions in obstetric brachial plexus palsy is still controversial. The authors analyzed the histopathology of neuroma-in-continuity of the upper trunk by study of the resected neuroma. METHODS: The neuroma-in-continuity of the upper trunk was studied histopathologically in 28 children with Erb palsy who had undergone resection of the neuroma and nerve reconstruction of the plexus at the age of 3 to 11 months. The authors recorded the distribution of myelinated motor nerve fibers and the proportions of collagen and regenerating nerve fibers traveling the neuroma, analyzed the relationship between the percentage of nerve fibers across the neuroma and findings of intraoperative neurophysiologic investigations and the patient's age at surgery, and compared the number of nerve fibers in C5 and C6 proximal to the neuroma with that in their normal counterparts. RESULTS: In the central segment of the neuroma, the structure of the upper trunk was replaced by copious collagen and sporadic nerve fibers wrapped by an undeveloped myelin sheath, and the percentage of collagen was statistically greater than that of the normal upper trunk. The mean percentage of regenerating nerve fibers across the neuroma was 41.83 percent (95 percent confidence interval, 38.69 to 44.69 percent) and this was not statistically correlated with the outcome of intraoperative neurophysiologic investigations or the patient's age at surgery. The number of nerve fibers was statistically less in C5 and C6 proximal to the neuroma than in their normal counterparts. CONCLUSIONS: The nerve structure of the neuroma-in-continuity is substantially damaged in obstetric brachial plexus palsy. Its resection followed by nerve reconstruction of the plexus is favored.

[A case-control study on the risk factors related to obstetric brachial plexus palsy].

OBJECTIVE: To identify the risk factors and related degrees associated to obstetric brachial plexus palsy(OBPP). METHODS: A case-control study was performed. Neonatal records of thirty-one cases with OBPP and their corresponding maternal records from the Department of Gynecology and Obstetrics of eight hospitals in Shanghai city from 1988 to 2002 were reviewed. Four controls, all living in Shanghai were selected to match each case and were born within the same year at the same hospital. The control group also included 124 cases without OBPP. According to the uniformed data and tables used were from medical records and from pregnant women. Epidemiological study was carried out on both case group and control group. Variables for analyses would include: (1) race, age, height, family history, pre-pregnancy weight, body mass index at the pre-pregnancy (weight/height2) on those pregnant women as well as on parity of their mothers; (2) the process of delivery which includeing clinic pelvis evaluation, height of uterus, abdomen circumference,antepartum weight,body mass index before delivery, mode of delivery,the duration of active phase and 2nd stage of labor, shoulder dystocia; (3) on neonates: sex, gestational age, birth weight,affected limb, Apgar scores of 1 and 5 minutes, other birth trauma and resuscitation of infant. Statistical tests applied to these data would include Student's T test for continuous variables and chi2 analysis for discrete data. Risk calculation of OBPP was performed by univariable and multivariable conditional logistic regression analysis. RESULTS: 12 factors related to expsure were identified for OBPP through univariable conditional logistic regression analysis. When multivariable conditional logistic regression model at P = 0.1 was applied, four factors such as cesarean (OR = 0.060), forceps (OR = 65.237), birth weight (OR = 35.468), and pre-pregnancy body mass index (OR = 23.901) were selected. CONCLUSION: Forceps delivery,macrosomia, and increase of pre-pregnancy body mass index (> or = 21) were risk factors of OBPP in the order of degrees to risk while cesarean seemed to serve as a protective factor.