• 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 Trauma and Injury
• /
• v.26 no.4
• /
• pp.286-290
• /
• 2013

Purpose: To report the postoperative Clinical and Radiological outcomes following distal femoral fractures in elderly patients compared with young patients. Methods: From March, 1996 to March, 2012, 83 patients who received surgical treatment for fractures of the distal femur were enrolled in this retrospective study. Ages more than 65 was named group A. Group A was 49 cases and mean age is 72.5 year(65~91year). Group B was 49 cases and mean age is 45.7 year(16~61 year). Surgical methods are retrograde IM nail, locking compression plate, cannulated screw and postoperative rehabilitation is no difference between two groups. Clinical results were evaluated using Neer scores, radiographic results and the presence of clinical complications. Results: The mean union period was 18.4(12-40) weeks in group A and 17(10-24) weeks in group B. Neer functional scores are no significant statistical difference between two groups. There are 5 cases metal breakage in group A and 1case in group B. There are 3 cases nonunion in group A and 1 case in group B. Conclusion: In the case of fractures of the distal femur in elderly patients, locking plate using minimally invasive percutaneous periosteal osteosynthesis (MIPPO) technique may be one of the most effective methods and preoperative bone stock evaluation in important.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.11
• /
• pp.2777-2785
• /
• 2000

In cementless total hip replacement(THR), an initial stability of the femoral component is important to long term fixation of femoral stem. The intial stability has close relationship with the relative displacement of prosthessis and sponge bone at the proximal of femur. After implantation of the proshesis, the surrounding bone is partially shielded from load carrying and starts to resorb. Stress shielding is the cause of the loss of proximal bone. Assessing stress distribution of femur is important to predict stress shielding. The initial stability and the stress shielding were investigated for two loading conditions approximating a single leg stance and a stair climbing. Three types of stems were studied by the finite element method to analyze the biomechanical effects of distal filling of cementless femoral stems. Three types of stems empolyed are a distal filling stem, a distal flexible stem, and a distal tapered stem.

• Proceedings of the KSME Conference
• /
• 2000.04a
• /
• pp.387-392
• /
• 2000

In cementless total hip replacement(THR), an initial stability of the femoral component is important to long term fixation of femoral stem. The initial stability has close relationship with the relative displacement of prosthesis and spongy bone at the proximal of femur. After implantation of the prosthesis. the surrounding bone is partially shielded from load carrying and starts to resort. Stress shielding is the cause of the loss of proximal bone. Assessing stress distribution of femur is important to predict stress shielding. The initial stability and the stress shielding were investigated for two loading conditions approximating a single leg stance and a stair climbing. Three types of stems were studied by the finite element method to analyze the biomechanical effects of distal filling of cementless femoral stems, Three types of stems employed are a distal filling stem, a distal flexible stem, and a distal tapered stem.

• Korean Journal of Veterinary Research
• /
• v.46 no.3
• /
• pp.285-289
• /
• 2006

This study was performed to assess the growth plate closure time with aging in the Korean native goat. Radiographs of proximal and distal epiphysis of humerus, radius, ulna, femur and tibia were obtained at 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 17, 18, 20, 21, 30, 43 and 52 weeks after birth in 30 Korean native goats. The secondary ossification centers were scrutinized and assessed the maturity process on the basis of the criteria(stage 0 to 10). The secondary ossification centers of proximal and distal epiphysis of humerus, radius, femur and tibia and proximal ulna epiphysis appeared immediately after birth. While, that of distal ulna epiphysis appeared during the 1st to 2nd week of life. The fusion of distal humeral epiphysis occurred during the period from 8 to 12 months. The fusion of proximal radial epiphysis and distal tibial epiphysis were found at 1 year. The fusion of proximal and distal epiphysis of ulna and femur, proximal epiphysis of humerus and tibia and distal epiphysis of radius were found at 1 year or more than 1 year. As a result, growth plate closure was highly related to age in the Korean native goat and it is suggested that the estimation of animal's age might be useful by illustration of maturity process of the secondary ossification centers in the Korean native goat.

• Physical Therapy Korea
• /
• v.3 no.1
• /
• pp.65-72
• /
• 1996

The purpose of this study was to introduce rotation-plasty procedure and prosthetic ambulation training. The recent development of chemotherapy and diagnostic facility have permitted the orthopaedic surgeons to try limb saving procedures rather than amputations for the treatment of the malignant bone tumors. If the tumors around the knee joint were treated by mid-thigh amputation or hip disarticulation, it would impose the client with a great handicap for rehabilitation. Rotation-plasty procedure was first done by Borggreve, in 1930 for the congenital short femur. Recently this procedure was used a malignant bone tumor at the distal femur by Kotz and Salzer in 1982. In spite of its cosmetic problem of the distal stump, this procedure has the great functional advantage of converting the above-knee amputation to the below-knee amputation. The inverted foot was also good to control the prosthesis as a below-knee stump and heel functioned as a patella to support the body weight. This 15 years old girl case was had rotation-plasty due to osteosarcoma of the distal femur with 3rd postoperative chemotherapy, and admitted to Yonsei rehabilitation hospital for prosthetic ambulation training. Then, the case had excellent functional results of prosthetic ambulation training with rotaion-plasty after 3 months.

• The Journal of the Korean bone and joint tumor society
• /
• v.19 no.2
• /
• pp.74-77
• /
• 2013

The guidelines for the treatment of massive bone defects caused by bone resection due to tumors have changed from amputation to limb salvaging surgery. Limb salvaging surgery using endoprotheses is a well-established procedure. However, Aseptic loosening, infection, and mechanical defect remain significant problems. Among them, we experienced the case with a breakage of polyethylene lock of MUTARS$^{(R)}$ distal femur tumor Endoprostheses.

• Archives of Reconstructive Microsurgery
• /
• v.14 no.1
• /
• pp.50-56
• /
• 2005

There are limited treatment options in the reconstruction of the very large defect in the metaphyseal portion of distal femur and proximal tibia. Fibula is one of the most popular donor of the long bone reconstruction in reconstructive microsurgical field. It has many advantages such as very strong strut tubular bone, very reliable vascular anatomy with large vascular diameter and long pedicle. There are limited donor site problems such as transient peroneal nerve dysfunction. In those situations with the huge long bone defects in distal femur or proximal tibia, the defective bony shape and strength of the transplanted fibular bone is not enough if only one strut of the fibula is transferred. We performed 7 cases of "doule barrel" fibular transplantation on the metaphyseal portion of distal femur and proximal tibial large defects in which it is very difficult to fill the bony gap with conventional bone graft or callotasis methods. It takes averaged 8.3 months since that procedure to obtain bony union. After solid union of the transferred double barrelled fibular graft. There were no stress fracture in our series. So we can propose double barrel fibular graft is useful method in those cases with very large bone defect on the metaphysis of large long bone.

• Journal of Trauma and Injury
• /
• v.36 no.4
• /
• pp.458-461
• /
• 2023

Epiphyseal dislocations and fractures frequently occur in children and adolescents. However, these injuries seldom involve the distal femur, and bilateral cases are even rarer. We present an unusual case of bilateral epiphyseal detachment of the femur in a 21-year-old man who was involved in a traffic accident. Open reduction and fixation surgery were performed 5 days after the incident. The patient experienced favorable progress, with consolidation occurring at 3 months. No lower limb length discrepancies were observed at the 20-month follow-up. In summary, bilateral distal femoral epiphyseal detachment is an uncommon condition that can be effectively treated through surgical intervention.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.15 no.4
• /
• pp.17-31
• /
• 2002

Objective : This study was carried out to investigate the effects of the hormones and cytokines associated with bone metabolism in ovariectomized rats. Method : Twenty-four Female-Sprague-Dawley rats were divided into sham operated(normal) group, ovariectomized(control)group, ovariectomized and treated with extract Caraganae Sinicae Radix(treated) group. Each group was investigated the changes of body weight at 3,5,7weeks after treatment, and femur weight, femur/body weight, thickness of compact bone of body of femur, area of cancellous bone of distal epiphysis of femur, serum estrogen, serum calcitonin, serum parathormone, serum Tumor Necrosis $Factor-{\alpha}$, serum $lnterleukin-1{\beta}$ at 7weeks after treatment. The results were summerized as follows; 1. The treated group showed significant change in body weight compared with the control group at 5,7weeks after treatment. 2. The treated group revealed significant increases in femur/body weight compared with the control group. 3. The treated group showed a little thicker compact bone of body of femur than the control group. 4. The area of cancellous bone of distal epiphysis of femur in treated group was increased significantly compared with control group. 5. The level of serum estrogen showed no change compared with control group. 6. The level of serum calcitonin showed no change compared with control group. 7. The level of serum parathormone was decreased in treated group significantly compared with control group. 8. The level of serum $TNF-{\alpha}$ was decreased in treated group significantly compared with control group. 9. The level of serum $interleukin-1{\beta}$ showed no change compared with control group. The results indicate that Caraganae Sinicae Radix inhibits bones resorption in ovariectomized rats by it's lowering effects on serum parathormone and $TNF-{\alpha}$.