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Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_4 | Pages 134 - 134
1 Feb 2017
Majima T Matsui S Nishiike O Takahashi K Oshima Y Iizawa N Takai S
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Introduction

In order to achieve good clinical results in TKA, soft tissue balance is important. Soft tissue balance is closely related to knee kinematics which affects clinical results.

Modified gap balancing technique is one of the standard techniques for posterior stabilized (PS) TKA. On the other hand, appropriate load for the measurement of gap balance has not been established.

The purpose of the present study is to measure the mechanical properties of soft tissue structure of knee sleeve in flexion and extension during PS TKA using newly developed balancer. The understanding of the mechanical properties is crucial. In particular if these properties are used as input for surgical procedures, standard technique for many surgeons will be established.

Materials and Methods

Medial compartmental osteoarthrosis (OA) patients (13 female and 7 male) were evaluated. Average age, BMI, and Varus deformity were 72.1 years, 26.9, and 12 degrees, respectively.

The newly developed center paddle balancer consists of a built-in spring (Fig. 1). Figure 2 shows the sequence of surgery and measurements. In the surgery, we measured the balance (degrees in Figure 1, A) and distance (mm in Figure 1, B) in extension with a load (Figure 1,C) at transition zone of toe region to linear region. Then, applying the load until flexion gap was the same as that in extension with a patella reduction, we measured the femoral component rotation from the balancer (degrees in Figure 1, A). The anterior and posterior femoral cuts were performed according to measured femoral component rotation which angle is parallel to tibial cut surface.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_9 | Pages 23 - 23
1 May 2016
Matsui S Majima T Mominoki K Koizumi R Kawaji H Takahashi K Takai S
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Introduction

Some patients complain ingrown pain or discomfort after implanting Co-Cr conventional endprosthesis of the hip. Some of this complaint may be attributable for effect on cartilage metabolism. It have been reported that ceramic is bioinert for biological tissue. On the other hand, metal including cobalt-chrome (Co-Cr) have some detrimental effect on biological tissue. However, there is no report concerning acetabular cartilage metabolism after hip endprosthesis implantation.

In the present study, we hypothesized that ceramic head have small detrimental effect on cartilage cell metabolism. Specific aim of the study is to compare the protein level of inflammation related cytokines, amount of hyaluronic acid (HA) in culture media, and cartilage mRNA expression in organ culture model of hip end prosthesis implanted using ceramic head and Co-Cr head.

Materials and Methods

Six acetabulum of 3 matured crossbred pig (average weight: 36 +/− 3.6kg) was retrieved. Animal experiment was performed under the rules of ethical committee of animal experiment. Average diameter of pig acetabulum was 26.3 +/− 0.6 mm. Just after sacrifice, mechanical loading using Instron testing machine with 26mm diameter of Co-Cr in right hip and Ceramic heads in left hip was performed in culture media. Ten thousand cycles of cyclic compression and rotation load (1.5kN to 0.15kN of compression and 12 degrees of rotation) to cartilage was applied at 1Hz (Figure 1).

Culture media was analyzed for protein levels of inflammation related cytokines and amount of HA. Relative quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) from acetabular cartilage was performed as previously reported using specific primer sets for type II collagen, aggrecan, TNF-alpha, Interleukine-1 and 6, and MMP-1, 3, 13.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 40 - 40
1 Jan 2016
Suzuki M Shirasaka W Yamamoto E Uetsuki K Sakai M Nakamura J Sasho T Takahashi K
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Introduction

In total knee arthroplalsties, there are risks of revision surgeries because of aseptic loosening, polyethylene wear, and metal component breakage. The data such as model, type, size, and manufacturing companies are required at the time of revision surgeries. However, it is sometimes difficult to acquire such data due to patient's change of address and the elimination and consolidation of hospitals in the long-term. Therefore, we try to use the Radio Frequency IDentification (RFID) in the total knee joint system.

Materials and methods

The FerVID family (Fujitsu Co. Ltd., Tokyo, Japan) was prepared as the RFID tag. It was radio-resistant below the dose of 50kGy, which allowed gamma sterilization. The RFID tags were embedded into the anterior side of GUR 1050 UHMWPE inserts and 0.3wt% vitamin E blended UHMWPE. The UHMWPE inserts were manufactured by thecompression molding method at the maximum temperature of 220°C and the maximum compressive force of 245kgf/cm2. The manufactured inserts were implanted in fresh cadaveric knees. The tibial base plate was made of Ti6Al4V. The femoral components were made of Co-Cr-Mo or Ti-6Al-4V. Communication Performance was measured with the interrogator (DOTR-920 MHz-band, Tohoku Systems Support Co. Ltd., Miyagi, Japan). The transmission output was up to 1W. Received Signal Strength Indicator (RSSI) was measured 500 times at 15 mm away from the surface of skin in the extension and 90° flexion of the knee (Fig1).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_3 | Pages 76 - 76
1 Jan 2016
Nakamura H Takahashi K Sato A Takai S
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Back ground

In 1970's, condylar type knee prosthese with anatomic design appeared, however, joint flexion was not satisfactory. Y/S II total knee arthroplasty (TKA) was developed to obtain deep flexion together with bilateral ligament balance in 1980. The articular surface of the tibial component was flattened to permit femoral shift posteriorily during knee flexion. Medial and lateral soft tissue release was determined by a unique ligament tensor both at flexion and extension. A metal tray was embedded in polyethylene, which had a shape of glasses frame. Though the usage of Y/SII TKA was finished in 1984, we here studied its long term surgical results using the Kaplan-Meyer method.

Study design

From 1988 to 1991, 122 knees were replaced by Y/SII TKA in 81 patients with rheumatoid arthritis (RA). Among them, 24 joints in 12 patients were examined directly. The average age of follow-up was 19.5 years. The survival rate was investigated according to medical records.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_3 | Pages 147 - 147
1 Jan 2016
Sato A Nakamura H Takahashi K Takenouchi K Kawaji H Takai S
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Purpose

Clinical outocome of revision total elbow arthroplasty(TEA) in rheumatoid arthritis(RA) patients were evaluated.

Methods

Clinical outocome of revision TEA that underwent between 2005 and 2013 were evaluated. Causes of revision, implanted revised prosthesis, a clinical score (the Japanese Orthopaedic Association (JOA) elbow assessment score), the arc of motion and complications were investigated. Totally, 6 patients underwent revision TEA. The patients were females with a mean age of 60.4 years (range, 32 to 72).


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 346 - 346
1 Mar 2013
Suzuki M Nakamura J Sasho T Kim IY Ohtsuki C Shirasaka W Takahashi K
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The bioactive polyetheretherketone (PEEK) was fabricated by the combination of PEEK and CaO-SiO2 particles, which formed hydroxyapatite on its surfaces in simulated body fluid and showed good mechanical propeties. The study revealed osteoblast-like cell proliferation and gene expression on the bioactive PEEK.

Materials and Methods

Peek and bioactive PEEK discs (24 mm in diameter and 2 mm in thickness) were prepared. Bioactive PEEk was produced by the combination of 80 vol% Peek powder and 20 vol% CaO-SiO2 particles (30CaO · 70SiO2). Discs were sterilized with ethylene oxide gas. The study was approved by the ethics committee in Chiba University. Human osteoblast-like cells were used in the study. The cells at passage 3–5 were used in the experiments. 2 × 105cells /disc were culture at 37°C in a humidified atmosphere with 5% CO2, and the media was replaced every 3 days. At days 3, 7, 21, the culture media, cells and discs were collected respectively. Cell attachment assay was performed. Cells were seeded at a density of 4 × 105 cells /well and incubated for 2 hours at 37 C in a humidified atmosphere with 5% CO2. The cells on the discs were evaluated by DNA content. The real-time PCR was performed with regard to type I collagen (COLI), osteocalcin (OC), osteonectin (ON), osteopontin (OPN), and GAPDH. The alkaline phosphatase activity (ALP) was measeured at 3, 7, and 21 days, which samples as used in the DNA-content assay. Alizalin Red Staining was performed at day 21 to quantify calcification deposits in discs. Results were analyzed using Student's t-test with at least three samples. The level of siginificance was set at p=0.05.

Results

The content of DNA showed similar increases on PEEK and bioactive PEEK in the course of day 3, 7, 21. The cell attachment of bioactive PEEK was two times larger than that of PEEK. Real-time PCR results of human osteoblast-like cells cultured on PEEK and bioactive PEEK discs were shown in Fig. 1. There were no significant differences between cells on PEEK and bioactive PEEK with respect to COL I and ON mRNA expression. However, human osteoblast-like cells on bioactive PEEK presented higher expression of OPN and OCN mRNA at day 21. No significant differences were found in ALP activity of both discs. Calcification deposits were observed only on bioactive PEEK at day 21


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XL | Pages 184 - 184
1 Sep 2012
Takahashi K Kambe Y Hayashi N Yamada K Yamamoto K Kojima K Tamada Y Tomita N
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INTRODUCTION

Several reports suggest that low-intensity pulsed ultrasound stimulation (LIPUS) facilitates chondrogenesis1). Recently it has been suggested that LIPUS may be transmitted via Integrin: a protein which mediates cellular attachment between cells and extracellular matrix2). In this study, the Arg-Gly-Asp (RGD) amino acid sequence, which is a ligand of Integrin, was induced to the fibroin substrates by either gene transfer or physical mixing, and the variation of chndrocyte response to LIPUS was evaluated.

EXPERIMENTAL METHODS

Three kinds of culture dishes coated with three diffrent fibroin aqueous solutions were prepared: 1 wild-type, 2 transgenic and 3 mixed. The wild-type aqueous solution was prepared from Bombyx mori silkworm cocoons. The transgenic aqueous solution was prepared from Bombyx mori silkworm cocoons in which RGD was interfused in the fibroin light chain3). The mixed aqueous solution was prepared simply by blending RGD peptides with the wild-type fibroin aqueous solution. Chondrocytes were asepically harvested from the joints of 4-week-old Japanese white rabbits and then subcultured on T-flasks and seeded at 2.0 × 105 cells/dish. LIPUS stimulation, with spatial and temporal average intensity of 30 mW/cm2 and a frequency of 1.71 MHz with a 200 ms tone burst repeated at 1.0 kHz, was applied to the chondrocytes at 12, 36, 60 hours and administered for 20 minutes each time. GAG production and the number of chondrocytes were measured by the Dimethylmethylene blue (DMMB) method4) and the LDH method5), respectively. Extracted mRNA from the chondrocytes was analyzed by using the Syber Green method, where the primers were designed for glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as the house-keeping gene, aggrecan and Sox 9. This data was analyzed using the two-sided Student's t-test.


The Journal of Bone & Joint Surgery British Volume
Vol. 84-B, Issue 6 | Pages 798 - 801
1 Aug 2002
Murata Y Takahashi K Yamagata M Sameda H Moriya H

In patients who underwent autogenous iliac bone grafting we studied prospectively injury to the lateral femoral cutaneous nerve (LFCN) in relation to the size (length, depth, width) of the graft. We also examined the neurological deficit, by questioning them about numbness and/or pain in the lateral thigh.

The risk of injury was significantly higher in those in whom the depth of the graft was more than 30 mm. With regard to the length of the graft the incidence of nerve injury was 20% when the graft was 45 mm long or more, 16% when it was between 30 mm and 45 mm long, and 8% when it was less than 30 mm long. We should inform patients of the possibility of such injury, and take size into consideration when harvesting grafts from the ilium.