• Clinics in Shoulder and Elbow
• /
• v.23 no.4
• /
• pp.198-202
• /
• 2020

Simple clavicle fractures can achieve satisfactory results through conservative treatment, and the less frequency of nonunion. Non-union or malunion can occur in displaced clavicle fractures or comminuted shaft fractures. Treatment of displaced comminuted clavicle shaft fractures is performed by holding together the free fragments with interfragmentary screws or wires and fixing them to the clavicle with a plate. Therefore, we performed interfragmentary fixation using open reduction and internal fixation with bioresorbable screws (Mg-Ca alloy, Resomet bioresorbable bone screw; U&I Corp.) and bioresorbable wires (Mg-Ca alloy, Resomet bioresorbable K-wire and pin, U&I Corp.) for displaced comminuted clavicle fractures (Robinson type 2B) and additionally used a metal plate. We expected decreased irritation and infection due to absorption after surgery. We report four cases that were treated in this way.

• Journal of Biomedical Engineering Research
• /
• v.16 no.4
• /
• pp.457-462
• /
• 1995

Unlike the usual bone plate and screw fracture fixation, an improved plate fixation method, which can transfer gradually physiological load to bones, is described. The key feature of the present method is to use washers between the plate and the screw. Bio-absorbable materials or non-ferrous materials with good damping characteristics are used to manufacture the washers. The purpose of this paper is to discuss potential advantages of the proposed method, and to show experimentally its improved impact-absorbing characteristics. Vibration experiments are carried out for pig femurs and cow tibias with and without the proposed washers. This experiments show that the washers can drop the first peak value suite substantially in the FRF plots. Although in-vivo experiments have not been conducted, the present fixation method appears to be a simple and effective alternative to the presently used method.

• Journal of the Korean Orthopaedic Association
• /
• v.56 no.4
• /
• pp.361-365
• /
• 2021

Pelvic fractures are high-energy injuries, often accompanied by damage to the adjacent tissues and organs. For patients with pelvic trauma, active treatment is required early in the injury, because mortality can increase if appropriate treatment is not provided. In most cases, however, minimally invasive surgery is considered because extensive surgery cannot be performed due to the patient's condition. Percutaneous fixation of the pubis has been introduced because it can be applied easily to achieve the stability of the anterior part of the pelvis. Although many studies introduced percutaneous fixation of pubic bone fractures, most describe screw fixation for nondisplaced fractures. When treating displaced fractures with percutaneous screw fixation, it is difficult for the guide pin or drill bit to avoid the joint surface. Using a bent guide pin could allow easy insertion of the cannulated screw while avoiding the articular surface.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.40
• /
• pp.37.1-37.7
• /
• 2018

Background: Fibrous dysplasia (FD) is characterized by the replacement of normal bone by abnormal fibro-osseous connective tissue and typically treated with surgical contouring of the dysplastic bone. When dysplastic lesions involve occlusion, not only is surgical debulking needed, orthognathic surgery for correction of dentofacial deformity is mandatory. However, the long-term stability of osteotomized, dysplastic bone segments is a major concern because of insufficient screw-to-bone engagement during surgery and the risk of FD lesion re-growth. Case presentation: This case report reviewed two patients with non-syndromic FD that presented with maxillary occlusal canting and facial asymmetry. Le Fort I osteotomy with recontouring of the dysplastic zygomaticomaxillary region had been performed. The stability of osseous segments were favorable. However, dysplastic, newly formed bone covered the previous plate fixation site and mild bony expansion was observed, which did not influence the facial profile. Including the current cases, 15 cases of orthognathic surgery for FD with dentition have been reported in the literature. Conclusion: The results showed that osteotomy did not appear to significantly reduce the long-term stability of the initial fixation insufficiency of the screw to the dysplastic bone. However, based on our results and those of the others, long-term follow-up and monitoring are needed, even in cases where the osteotomized segment shows stable results.

• Journal of the Korean Arthroscopy Society
• /
• v.10 no.1
• /
• pp.87-90
• /
• 2006

The complication caused by a bioabsorbable interference screw is rare after anterior cruciate ligament reconstruction. We report a case of delayed inflammatory reaction at the tibial tunnel and femoral tunnel where the graft tendon had been fixed with a bioabsorbable interference screw ($Bioscrew^{(R)}$) for anterior cruciate ligament reconstruction using bone-patellar tendon-bone autograft.

• Clinics in Shoulder and Elbow
• /
• v.8 no.1
• /
• pp.19-22
• /
• 2005

Purpose: The causes of twelve cases of the mid-shaft clavicle nonunion and the results of internal fixation with plate and bone graft were investigated. Materials and method: From August 1997 to March 2003, twelve cases of the mid-shaft clavicle nonunion were operated with internal fixation with plate and bone graft. The duration of follow-up was average 13 months. Results: The causes of the mid-shaft clavicle nonunion included severe associated injury, severe initial displacement of the fracture fragments and insecure fixation. All cases were operated with internal fixation with plate and bone graft. According to the factor for evaluations of results, using a rating scale of excellent (no apparent factors), good (one factor), fair (two factors), poor (more than three factors), the results showed 10 excellent, 1 good and 1 poor. Screw loosening was developed in only one case . Conclusion: The internal fixation with plate and bone graft of the mid-shaft clavicle nonunion after failed conservative treatment achieved excellent results and seemed to be the procedure of choice for mid-shaft clavicle nonunion.

• Journal of Korean Neurosurgical Society
• /
• v.49 no.6
• /
• pp.351-354
• /
• 2011

Objective : This investigation was conducted to evaluate a new, safe entry point for the C2 pedicle screw, determined using the anatomical landmarks of the C2 lateral mass, the lamina, and the isthmus of the pars interarticularis. Methods : Fifteen patients underwent bilateral C1 lateral mass-C2 pedicle screw fixation, combined with posterior wiring. The C2 pedicle screw was inserted at the entry point determined using the following method : 4 mm lateral to and 4 mm inferior to the transitional point (from the superior end line of the lamina to the isthmus of the pars interarticularis). After a small hole was made with a high-speed drill, the taper was inserted with a 30 degree convergence in the cephalad direction. Other surgical procedures were performed according to Harm's description. Preoperatively, careful evaluation was performed with a cervical X-ray for C1-C2 alignment, magnetic resonance imaging for spinal cord and ligamentous structures, and a contrast-enhanced 3-dimensional computed tomogram (3-D CT) for bony anatomy and the course of the vertebral artery. A 3-D CT was checked postoperatively to evaluate screw placement Results : Bone fusion was achieved in all 15 patients (100%) without screw violation into the spinal canal, vertebral artery injury, or hardware failure. Occipital neuralgia developed in one patient, but this subsided after a C2 ganglion block. Conclusion : C2 transpedicular screw fixation can be easily and safely performed using the entry point of the present study. However, careful preoperative radiographic evaluation, regardless of methods, is mandatory.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.12 no.2
• /
• pp.48-54
• /
• 1990

This is a report of 4 cases of the surgical correction of mandibular prognathism with chief complaint of mastication difficulty, facial asymmetry and protrusive chin. We performed sagittal spit ramus osteotomy for the prognathism, we used the repositioning plate for conserving the condylar segment into its original position and fixed the osteotomized bone segments rigidly with adjustable monocortical plate. Intermaxillary fixation was performed during 2 weeks. As a results, we found the following advantage. 1. Rigid fixation effect like the fixation by the tandem screw. 2. Decreased postoprative swelling. 3. It is needless to do the stab incision for the transbuccal set instrument. 4. It is more convenient to perform the rigid fixation in the monocortical plate method than screw technique.

• Journal of Biomedical Engineering Research
• /
• v.31 no.3
• /
• pp.199-209
• /
• 2010

The locking compression plates-distal femur(LCP-DF) are being widely used for surgical management of the extra-articular complex fractures of the distal femur. They feature locking mechanism between the screws and the screw holes of the plate to provide stronger fixation force with less number of screws than conventional compression bone plate. However, their biomechanical efficacies are not fully understood, especially regarding the number of the screws inserted and their optimal configurations. In this study, we investigated effects of various screw configurations in the shaft and the condylar regions of the femur in relation to structural stability of LCP-DF system. For this purpose, a baseline 3-D finite element (FE) model of the femur was constructed from CT-scan images of a normal healthy male and was validated. The extra-articular complex fracture of the distal femur was made with a 4-cm defect. Surgical reduction with LCP-DF and bone screws were added laterally. To simulate various cases of post-op screw configurations, screws were inserted in the shaft (3~5 screws) and the condylar (4~6 screws) regions. Particular attention was paid at the shaft region where screws were inserted either in clustered or evenly-spaced fashion. Tied-contact conditions were assigned at the bone screws-plate whereas general contact condition was assumed at the interfaces between LCP-DF and bone screws. Axial compressive load of 1,610N(2.3 BW) was applied on the femoral head to reflect joint reaction force. An average of 5% increase in stiffness was found with increase in screw numbers (from 4 to 6) in the condylar region, as compared to negligible increase (less than 1%) at the shaft regardless of the number of screws inserted or its distribution, whether clustered or evenly-spaced. At the condylar region, screw insertion at the holes near the fracture interface and posterior locations contributed greater increase in stiffness (9~13%) than any other locations. Our results suggested that the screw insertion at the condylar region can be more effective than at the shaft during surgical treatment of fracture of the distal femur with LCP-DF. In addition, screw insertion at the holes close to the fracture interface should be accompanied to ensure better fracture healing.

• Journal of the Korean Arthroscopy Society
• /
• v.6 no.1
• /
• pp.60-63
• /
• 2002

Purpose : The purpose of this study was to introduce new femoral fixation technique using a cross-pin and a bioabsorbable interference screw in hamstring ACL reconstruction. Method : Semitendinosus and gracilis were harvested for quadrapled graft. After tibial tunnel had been made, femoral tunnel was made 35 mm in depth. Then the graft passed through the tunnels. Cross-pin was fixed through the drill hole which had been made through upper sleeve of the Rigidfix system. While pulling the graft, bioabsorbable interference screw was fixed through the anteromedial portal. Conclusion : We introduced the new femoral fixation technique using a cross-pin and a bioabsorbable interference screw as a good method with high fixation strength and tight graft-bone contact.