Chang-Dong Han

Comparison of simultaneous bilateral and staged bilateral total knee arthroplasty in terms of perioperative complications.

We compared bilateral total knee arthroplasty (TKA) performed at a single session vs those performed at 2 separate sessions with respect to complications, amount of blood loss, and length of hospital stay. Study participants included 119 consecutive patients undergoing simultaneous bilateral TKA and an additional 119 patients undergoing staged bilateral TKA. Systemic complication in the simultaneous bilateral TKA was significantly higher statistically than that in the staged bilateral TKA. Therefore, performing simultaneous bilateral TKA in elderly or high-risk patients results in a significantly higher rate of systemic complications. Simultaneous bilateral TKA is a relatively safe and beneficial procedure with a minimal increase in the risk of systemic complications. However, this procedure should be conducted carefully, particularly in elderly and high-risk patients.

A prospective, randomized, double-blind, multicenter comparative study on the safety and efficacy of Celecoxib and GCSB-5, dried extracts of six herbs, for the treatment of osteoarthritis of knee joint.

ETHNOPHARMACOLOGICAL RELEVANCE This prospective, randomized, double-blind, multicenter study compared the efficacy and safety of Celecoxib and GCSB-5, a new product from extracts of six herbs, for the treatment of knee osteoarthritis. MATERIALS AND METHODS A total of 198 eligible patients were randomly assigned to the Celecoxib group (n=99 patients) or the GCSB-5 group (n=99 patients) for the 12-week study. The amount of change and percentage of the change in Western Ontario and McMaster Universities (WOMAC) Arthritis Index from the baseline, the change in pain on walking by visual analogue scale (VAS), physicians global assessment on response to therapy (PGART) by five point Likert scale, and the amount of rescue medicine taken were used as parameters for efficacy. Adverse drug reactions (ADRs) were carefully investigated. RESULTS The WOMAC score improved in both the Celecoxib group and GCSB-5 group by 20.5 and 21.3 (P=0.79). The percentage of the change in WOMAC score were -42.0% and -38.9% (P=0.54). The pain VAS score decreased by 29.9 and 27.9 (P=0.58). The responders by PGART were 95.3% and 93.8% (P= 0.66), and the median amount of rescue medicine taken were 2.0 and 6.5 tablets (P=0.06). The incidence of ADRs were 31.3% and 21.2% (P=0.11). The most common ADRs were gastrointestinal system related; 17.2% in GCSB-5 group and 22.2% in Celecoxib group. Any severe ADR was not observed in either group. CONCLUSIONS The result of this study supports that GCSB-5 is comparable to Celecoxib in terms of the efficacy and safety for the treatment of osteoarthritis of knee joint.

Straight Tapered Titanium Stem With Alumina Bearing in Cementless Primary Total Hip Arthroplasty: A Minimum 5-Year Follow-Up

The aim of this study was to assess the midterm results of primary cementless total hip arthroplasty using a tapered stem and alumina bearing couple in active patients. After a minimum of 5 years of follow-up, 78 arthroplasties in 72 patients were reviewed retrospectively. The mean Harris hip score was 94 points, and 2 hips had thigh pain. All components radiographically demonstrated stable fixation by bone ingrowth and mild stress shielding of the proximal femur were noted in 14% of hips. There was no significant osteolysis or aseptic loosening. There was a ceramic head fracture in 1 hip and audible sounds in 2 hips. The results of total hip arthroplasty with a straight, tapered, proximally porous-coated stem and alumina-on-alumina bearing were encouraging for active patients.

Minimum 5-year Follow-up Results of Minimally Invasive Total Knee Arthroplasty Using Mini-Keel Modular Tibial Implant.

Purpose To evaluate the minimum 5-year mid-term clinical and radiological results of minimally invasive surgery total knee arthroplasty (MIS-TKA) using a mini-keel modular tibia component. Materials and Methods We retrospectively evaluated 254 patients (361 cases) who underwent MIS-TKA between 2005 and 2006. The latest clinical and radiological assessments were done in 168 cases that had been followed on an outpatient basis for more than 5 postoperative years. Clinical results were assessed using the Hospital for Special Surgery (HSS) score and Knee Society score. Radiological evaluation included measurements of knee alignment. Results The average postoperative knee range of motion and HSS score were 134.3°±12.4° and 92.7°±7.0°, respectively. The average postoperative femorotibial angle and tibial component alignment angle were 5.2°±1.7° valgus and 90.2°±1.6°, respectively. The average tibial component posterior inclination was 4.8°±2.1°. The percentage of cases with tibial component alignment angle of 90°±3° was 96.1%, and that with the femorotibial angle of 6°±3° valgus was 94.0%. Radiolucent lines were observed in 20 cases (12.0%): around the femur, tibia, and patella in 14 cases, 10 cases, and 1 case, respectively. However, they were less than 2 mm and non-progressive in all cases. The survival rate was 99.4% and there was no implant-related revision. Conclusions MIS-TKA using a mini-keel modular tibial plate showed satisfactory results, a high survival rate, and excellent clinical and radiological results in the mid-term follow-up.

Extramedullary Tibial Bone Cutting Using Medial Cortical Line in Total Knee Arthroplasty

Purpose This study aims to identify the effectiveness of the medial cortical line for attaining a more accurate tibial component alignment in proximal tibial resection using an extramedullary alignment rod. Materials and Methods The study examined 100 cases of total knee arthroplasty performed from December 2013 to February 2014 in a retrospective manner. On a preoperative anteroposterior (AP) radiograph of the entire tibia, we identified the medial cortical line that runs parallel to the tibial anatomical axis and passes the medial tibial spine, and measured the point where the medial cortical line crosses between the medial malleolus and the lateral malleolus in the ankle joint. Results The preoperative AP radiograph of the tibia showed the medial cortical line passing the point 40.4%±0.8% medial to the distance from the medial malleolus to the lateral malleolus including the skin thickness in the ankle joint. When the proximal tibial resection was performed with the extramedullary tibial cutting guide aligned with the medial cortical line, the tibial component angle averaged 0.7°±0.3° varus and the alignment accuracy of the tibial component within 0°±3° varus amounted to 97.0%. Conclusions The use of the medial cortical line in proximal tibial resection with an extramedullary tibial cutting guide allowed for relatively accurate alignment of the tibial component.

Optimum Design of a Pilger Mill Process for Wire Forming Using CAD/CAE

The optimum design of a die shape for Pilger mill process was carried out using FEM analyses considering various processing factors. The important design parameters of the Pilger mill machine are feed rate and profile of the grooved die. Optimum design procedure was conducted in order to investigate effects on forming load and the deformed shape of a material depending on the die surface profiles. Profiles of the die surface for the optimum design were testified with linear, cosine and quadratic curves considering physical forming process. The results of the analyses provided that the model of the quadratic profile gave the lowest forming load and the proper deformed shape.

Effect of Growth Factors on Type I Collagen Synthesis in Cultured Rabbit's Deep Flexor Tendon Cell

Purpose : This study focuses on the change of the expression of type-I collagen mRNA and extent of collagen synthesis caused by four kinds of growth factos (TGF-, IGF-I, EGF, PDGF) and their combinations to elucidate the effects of growth factors on rabbits flexor tendon. Materials and Methods : Cells were isolated from rabbit’s flexor tendons and cultured with DMEM containing 0.5% fetal bovine serum. Growth factors were then given either independently or in combination. On the 5th, 10th, and 15th day, the cells were collected and the cell proliferation rate was analyzed. The expression of type-I collagen mRNA was analyzed by Northern blot. Results : The expression of type-I collagen mRNA increased significantly in the IGF, PDGF, PDGF/EGF, and PDGF/IGF groups (p