Trans-obturator cable fixation of open book pelvic injuries

Operative treatment of ruptured pubic symphysis by plating is often accompanied by complications. Trans-obturator cable fixation might be a more reliable technique; however, have not yet been tested for stabilization of ruptured pubic symphysis. This study compares symphyseal trans-obturator cable fixation versus plating through biomechanical testing and evaluates safety in a cadaver experiment. APC type II injuries were generated in synthetic pelvic models and subsequently separated into three different groups. The anterior pelvic ring was fixed using a four-hole steel plate in Group A, a stainless steel cable in Group B, and a titan band in Group C. Biomechanical testing was conducted by a single-leg-stance model using a material testing machine under physiological load levels. A cadaver study was carried out to analyze the trans-obturator surgical approach. Peak-to-peak displacement, total displacement, plastic deformation and stiffness revealed a tendency for higher stability for trans-obturator cable/band fixation but no statistical difference to plating was detected. The cadaver study revealed a safe zone for cable passage with sufficient distance to the obturator canal. Trans-obturator cable fixation has the potential to become an alternative for symphyseal fixation with less complications.

Trans-obturator Cable Fixation for Disrupted Pubic Symphysis: A Reasonable Option Compared to Plating?

Operative treatment of ruptured pubic symphysis by plating is often accompanied by complications. Trans-obturator cable fixation might be a more reliable technique; however, have not yet been tested for stabilization of ruptured pubic symphysis. This study compares symphyseal trans-obturator cable fixation versus plating through biomechanical testing and evaluates safety in a cadaver experiment. APC type II injuries were generated in synthetic pelvic models and subsequently separated into three different groups. The anterior pelvic ring was fixed using a four-hole steel plate in Group A, a stainless steel cable in Group B, and a titan band in Group C. Biomechanical testing was conducted by a single-leg-stance model using a material testing machine under physiological load levels. A cadaver study was carried out to analyze the trans-obturator surgical approach. Peak-to-peak displacement, total displacement, plastic deformation and stiffness revealed a tendency for higher stability for trans-obturator cable/band fixation but no statistical difference to plating was detected. The cadaver study revealed a safe zone for cable passage with sufficient distance to the obturator canal. Trans-obturator cable fixation has the potential to become an alternative for symphyseal fixation with less complications.

The additional iron cable fixation between proximal patella and tibial tuberosity to treat AO/OTA 34C3 patellar fracture

Background:It is very difficult to deal with AO/OTA 34C3 patellar fracture. Although the modified Kirschner wire tension band, the cerclage and plate has been proposed to treat it, the result is not very good. We found that if the fixation was not firm enough after the modified Kirschner wire tension band with or without the cerclage had been carried out, the additional iron cable fixation between proximal patella and tibial tuberosity could resolve it effectively.Methods:Retrospective analysis was completed. 21 patients with AO/OTA 34C3 patellar fracture were treated in our department from January 2014 to January 2018. They were divided into 2 groups according to the operation plan. Group 1 (normal group), with 12 patients, was treated with modified Kirschner wire tension band with or without cerclage cable. Group 2 (cable group), with 9 patients, was treated with the additional iron cable fixation between proximal patella and tibial tuberosity when the fixation was not firm enough after the modified Kirschner wire tension band with or without the cerclage had been completed.Results:The two groups of the age, sex ratio, trauma mechanism, operation time, free articular fragment, comorbidity and follow-up time had no significant statistical difference (P>0.05). There was no significant statistical difference between the two groups of the clinical results. (such as Bostman total score and its specific individual score, the excellent and good ratio, the complications, and the bone union time, etc.) (P>0.05).Conclusions:To deal with AO/OTA 34C3 patellar fracture, when the fixation of modified Kirschner wire tension band with or without the cerclage cable is not firm enough, the additional iron cable fixation between proximal patella and tibial tuberosity can resolve it effectively.

The additional iron cable fixation between proximal patella and tibial tuberosity to treat AO/OTA 34C3 patellar fracture

Background: It is very difficult to deal with AO/OTA 34C3 patellar fracture. Although the modified Kirschner wire tension band, the cerclage and plate has been proposed to treat it, the result is not very good. We found that if the fixation was not firm enough after the modified Kirschner wire tension band with or without the cerclage had been carried out, the additional iron cable fixation between proximal patella and tibial tuberosity could resolve it effectively.Methods: Retrospective analysis was completed. 21 patients with AO/OTA 34C3 patellar fracture were treated in our department from January 2014 to January 2018. They were divided into 2 groups according to the operation plan. Group 1 (normal group), with 12 patients, was treated with modified Kirschner wire tension band with or without cerclage cable. Group 2 (cable group), with 9 patients, was treated with the additional iron cable fixation between proximal patella and tibial tuberosity when the fixation was not firm enough after the modified Kirschner wire tension band with or without the cerclage had been completed.Results: The two groups of the age, sex ratio, trauma mechanism, operation time, free articular fragment, comorbidity and follow-up time had no significant statistical difference (P>0.05). There was no significant statistical difference between the two groups of the clinical results. (such as Bostman total score and its specific individual score, the excellent and good ratio, the complications, and the bone union time, etc.) (P>0.05).Conclusions: To deal with AO/OTA 34C3 patellar fracture, when the fixation of modified Kirschner wire tension band with or without the cerclage cable is not firm enough, the additional iron cable fixation between proximal patella and tibial tuberosity can resolve it effectively.

A Study on Structure Design of Cable-Driven Picking Manipulator

Fruit picking is a seasonal and labor-intensive work. The industry requires automatic fruit picking due to increasing labor costs and variability in picking skill. High accuracy, simple structure and low cost are expected to make the robot be readily accepted and widely used. Cable-driven transmission is more preferable than traditional system for some of its merits benefiting the production of small and light-weight manipulator. In this paper, the design of a differential cable-driven manipulator is presented. Different way of cable-driven transmission are analyzed and compared. The selection of cable material and the way of cable fixation and preload are studied. The mechanical structure of the manipulator’s arm driven by a differential drive capstan is designed.