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Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_5 | Pages 10 - 10
1 Apr 2019
Yoshioka T Okimoto N Kobayashi T Ikejiri Y Asano K Murata H Kawasaki M Majima T
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Soft tissue balance is important for good clinical outcome and good stability after TKA. Ligament balancer is one of the devices to measure the soft tissue balance. The objective of this study is to clarify the effect of the difference in the rotational position of the TKA balancer on medial and lateral soft tissue balance.

Materials and Methods

This study included with 50 knees of the 43 patients (6 males, 37 females) who had undergone TKA with ADLER GENUS system from March 2015 to January 2017. The mean age was 71.1±8.1 years. All patients were diagnosed with medial osteoarthritis of the knee. All implants was cruciate substituted type (CS type) and mobile bearing insert.

We developed a new ligament balancer that could be fixed to the tibia with keel and insert trial could be rotated on the paddle. We measured the medial and lateral soft tissue balance during TKA with the new balancer. The A-P position of the balancer was fixed on tibia in parallel with the Akagi line (A-P axis 0 group) and 20 degrees internal rotation (IR group) and 20 degrees external rotation (ER group). Soft tissue balance was measured in extension and 90 degrees of knee flexion on each rotational position.

Results

The mean angle of valgus and varus in IR group, 0 group and ER group were 4.6±2.2 degrees varus, 1.9±1.6 degrees varus and 0.4±2.4 degrees varus respectively in extension, and 5.5±3.0 degrees varus, 2.1±2.2 degrees varus and 0.7±3.2 degrees varus respectively in 90 degrees of knee flexion. There were significant differences between three groups in extension (p<0.0001) and flexion (p<0.0001). In other words, when the balancer was fixed on tibia with internal rotation against the Akagi line, the soft tissue balance indicated medial tightness. Conversely, when the balancer was fixed on tibia with external rotation against the Akagi line, the soft tissue balance showed lateral tightness.

The insert trial significantly rotated to opposite side against the position of balancer fixed.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 101 - 101
1 Jan 2016
Vigneron L Delport H Khairul A Kobayashi T DeBoodt S
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Introduction

A full 3D postoperative analysis, i.e. a quantitative comparison between planned and postoperative positions of bone(s) and implant(s) in 3D, is necessary for a thorough assessment of the outcome of the surgery, as well as to provide information that could be used to optimize similar procedures in the future. In this work, we present a method of postoperative analysis based on a pair of X-ray images only, which reaches a level of accuracy that is comparable with the results obtained with a 3D postoperative image.

Methods

The method consists in using 3D models of bones, segmented from 3D preoperative image (e.g. CT or MRI scans), and 3D models of implant, and aligning them independently to X-rays by matching contours manually drawn on the X-rays and projected contours. The result gives the relative postoperative position of bone and implant. The method was tested on a phantom consisting of commonly available femoral knee implant on a physical model of a femur (Sawbones®). Result was compared to the optical scan, considered as ground truth, of the implanted saw bone. Two studies were performed: inter-operator (six operators), and intra-operator (5 tests). In addition, the inter-operator study was repeated while asking all the operators to use the same pre-drawn contours. The results are presented by calculating the distance (anterior/posterior, proximal/distal, medial/lateral) between the centers of gravity, and the angles (varus/valgus, flexion/extension, external/internal rotations) of the implants from the X-ray based method and the ground truth.

Results were also compared with the relative position of bone and implant extracted from a 3D CT postoperative image. Saw bone and implant were first segmented from this image. In order to determine the position of the implant, despite the metal artefacts in the CT images, the 3D model of the implant was registered on the segmented implant.

All processing, including segmentation, registration of X-rays, and measurements, was performed using Mimics Innovation Suite 17.0 ®.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 144 - 144
1 Jan 2016
Yonemoto Y Okamura K Takeuchi K Hosokawa T Kaneko T Matsushita M Okura C Kobayashi T Takagishi K
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Background

Previously, the Coonrad-Morrey elbow system has typically been performed using linked-type total elbow arthroplasty (TEA) implants. However, this implant have been reported to be associated with some problems, such as wearing down, loosening, the complexity of the necessary surgical techniques and inappropriate implant size for Asian people.

The Discovery elbow system (Biomet Inc., Warsaw, US) has recently been developed and it has many advantages when compared to Coonrad-Morrey implant, but the treatment outcome for this system is unclear in patients with rheumatoid arthritis (RA).

Objectives

The aim of this study was to clarify the outcome of TEA using the Discovery elbow system.


The Bone & Joint Journal
Vol. 96-B, Issue 6 | Pages 789 - 794
1 Jun 2014
Sukegawa K Kuniyoshi K Suzuki T Ogawa Y Okamoto S Shibayama M Kobayashi T Takahashi K

We conducted an anatomical study to determine the best technique for transfer of the anterior interosseous nerve (AIN) for the treatment of proximal ulnar nerve injuries. The AIN, ulnar nerve, and associated branches were dissected in 24 cadaver arms. The number of branches of the AIN and length available for transfer were measured. The nerve was divided just proximal to its termination in pronator quadratus and transferred to the ulnar nerve through the shortest available route. Separation of the deep and superficial branches of the ulnar nerve by blunt dissection alone, was also assessed. The mean number of AIN branches was 4.8 (3 to 8) and the mean length of the nerve available for transfer was 72 mm (41 to 106). The transferred nerve reached the ulnar nerve most distally when placed dorsal to flexor digitorum profundus (FDP). We therefore conclude that the AIN should be passed dorsal to FDP, and that the deep and superficial branches of the ulnar nerve require approximately 30 mm of blunt dissection and 20 mm of sharp dissection from the point of bifurcation to the site of the anastomosis.

The use of this technique for transfer of the AIN should improve the outcome for patients with proximal ulnar nerve injuries.

Cite this article: Bone Joint J 2014;96-B:789–94.


The Bone & Joint Journal
Vol. 96-B, Issue 5 | Pages 597 - 603
1 May 2014
Nomura T Naito M Nakamura Y Ida T Kuroda D Kobayashi T Sakamoto T Seo H

Several radiological methods of measuring anteversion of the acetabular component after total hip replacement (THR) have been described. These studies used different definitions and reference planes to compare methods, allowing for misinterpretation of the results. We compared the reliability and accuracy of five current methods using plain radiographs (those of Lewinnek, Widmer, Liaw, Pradhan, and Woo and Morrey) with CT measurements, using the same definition and reference plane. We retrospectively studied the plain radiographs and CT scans in 84 hips of 84 patients who underwent primary THR. Intra- and inter-observer reliability were high for the measurement of inclination and anteversion with all methods on plain radiographs and CT scans. The measurements of inclination on plain radiographs were similar to the measurements using CT (p = 0.043). The mean difference between CT measurements was 0.6° (-5.9° to 6.8°).

Measurements using Widmer’s method were the most similar to those using CT (p = 0.088), with a mean difference between CT measurements of -0.9° (-10.4° to 9.1°), whereas the other four methods differed significantly from those using CT (p < 0.001).

This study has shown that Widmer’s method is the best for evaluating the anteversion of the acetabular component on plain radiographs.

Cite this article: Bone Joint J 2014; 96-B:597–603.


Bone & Joint Research
Vol. 1, Issue 9 | Pages 198 - 204
1 Sep 2012
Iwase T Takebayashi T Tanimoto K Terashima Y Miyakawa T Kobayashi T Tohse N Yamashita T

Objectives

In order to elucidate the influence of sympathetic nerves on lumbar radiculopathy, we investigated whether sympathectomy attenuated pain behaviour and altered the electrical properties of the dorsal root ganglion (DRG) neurons in a rat model of lumbar root constriction.

Methods

Sprague-Dawley rats were divided into three experimental groups. In the root constriction group, the left L5 spinal nerve root was ligated proximal to the DRG as a lumbar radiculopathy model. In the root constriction + sympathectomy group, sympathectomy was performed after the root constriction procedure. In the control group, no procedures were performed. In order to evaluate the pain relief effect of sympathectomy, behavioural analysis using mechanical and thermal stimulation was performed. In order to evaluate the excitability of the DRG neurons, we recorded action potentials of the isolated single DRG neuron by the whole-cell patch-clamp method.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 11 | Pages 1606 - 1613
1 Nov 2010
Oshima S Ishikawa M Mochizuki Y Kobayashi T Yasunaga Y Ochi M

We used interconnected porous calcium hydroxyapatite ceramic to bridge a rabbit ulnar defect. Two weeks after inducing the defect we percutaneously injected rabbit bone marrow-derived mesenchymal stromal cells labelled with ferumoxide. The contribution of an external magnetic targeting system to attract these cells into the ceramic and their effect on subsequent bone formation were evaluated.

This technique significantly facilitated the infiltration of ferumoxide-labelled cells into ceramic and significantly contributed to the enhancement of bone formation even in the chronic phase. As such, it is potentially of clinical use to treat fractures, bone defects, delayed union and nonunion.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 4 | Pages 580 - 585
1 Apr 2010
Shido Y Nishida Y Suzuki Y Kobayashi T Ishiguro N

We undertook a study of the anti-tumour effects of hyperthermia, delivered via magnetite cationic liposomes (MCLs), on local tumours and lung metastases in a mouse model of osteosarcoma. MCLs were injected into subcutaneous osteosarcomas (LM8) and subjected to an alternating magnetic field which induced a heating effect in MCLs. A control group of mice with tumours received MCLs but were not exposed to an AMF. A further group of mice with tumours were exposed to an AMF but had not been treated with MCLs. The distribution of MCLs and local and lung metastases was evaluated histologically. The weight and volume of local tumours and the number of lung metastases were determined. Expression of heat shock protein 70 was evaluated immunohistologically. Hyperthermia using MCLs effectively heated the targeted tumour to 45°C. The mean weight of the local tumour was significantly suppressed in the hyperthermia group (p = 0.013). The mice subjected to hyperthermia had significantly fewer lung metastases than the control mice (p = 0.005). Heat shock protein 70 was expressed in tumours treated with hyperthermia, but was not found in those tumours not exposed to hyperthermia.

The results demonstrate a significant effect of hyperthermia on local tumours and reduces their potential to metastasise to the lung.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 131 - 131
1 Mar 2010
Suzuki M Lee T Miyagi J Kobayashi T Sasho T Nakagawa K Fujiwara K Nishimura N Kuramoto K Uetsuki K Moriya H Takahashi K
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The aim of this study was to report a 3 year follow up of vitamin E add polyethylene in total knee arthroplasty. UHMWPE powder (GUR1050) was mixed with 0.3% of vitamin E before consolidation by direct compression molding. The vitamin E added UHMWPE was applied to the articular surface and patella in 65 patients (mean age, 69.6 years). Joint fluid concentrations of tocopherol and matrix metalloproteinase 9 were measured in vitamin E added UHMWPE cases one year after surgery, and were compared to those of conventional UHMWPE cases and osteoarthritis patients. Concentrations of α-tocopherol and γ-tocopherol were measured by using HPLC with ultraviolet-visible wavelength detection. Concentrations of matrix metalloproteinase 9 were detected by using enzyme immunoassay.

The Average Knee Society score were 91.7(clinical) and 76.7(functional). There were three failures (1 supracondylar fracture, and 2 skin necrosis). The average concentrations of α-tocopherol were 281.8μg/dL (10 cases) in the vitamin E group, 371.8μg/dL (15 cases) in the conventional group, and 317.8μg/dL (46 cases) in the osteoarthritis group. There were no significant differences among three groups. The average concentrations of γ-tocopherol were 43.4μg/dL in the vitamin E group, 52.3μg/dL in the conventional group, and 49.8μg/dL in the osteoarthritis group. There were no significant differences among three groups. The average concentrations of matrix metalloproteinase 9 were 83.2 ng/mL in the vitamin E group, 78.4 ng/mL in the conventional group, and 17.4 ng/mL in the osteoarthritis group. There was no significant difference between the vitamin E group and the conventional group. However, The matrix metalloproteinase 9 concentrations of the osteoarthritis group were significantly lower than others.

No cases exhibited measurable polyethylene wear or osteolysis and also no abnormal values relating to vitamin E on joint fluid examinations. At three year follow-up, vitamin E added polyethylene demonstrated the safe use for the human body.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 10 | Pages 1426 - 1433
1 Oct 2005
Kobayashi T Watanabe H Yanagawa T Tsutsumi S Kayakabe M Shinozaki T Higuchi H Takagishi K

Human bone-marrow mesenchymal stem cells have an important role in the repair of musculoskeletal tissues by migrating from the bone marrow into the injured site and undergoing differentiation. We investigated the use of autologous human serum as a substitute for fetal bovine serum in the ex vivo expansion medium to avoid the transmission of dangerous transfectants during clinical reconstruction procedures.

Autologous human serum was as effective in stimulating growth of bone-marrow stem cells as fetal bovine serum. Furthermore, medium supplemented with autologous human serum was more effective in promoting motility than medium with fetal bovine serum in all cases. Addition of B-fibroblast growth factor to medium with human serum stimulated growth, but not motility. Our results suggest that autologous human serum may provide sufficient ex vivo expansion of human bone-marrow mesenchymal stem cells possessing multidifferentiation potential and may be better than fetal bovine serum in preserving high motility.


Orthopaedic Proceedings
Vol. 85-B, Issue SUPP_I | Pages 31 - 31
1 Jan 2003
Takemitsu M Takemitsu Y Matsuno T Atsuta Y Kobayashi T Iwahara T Kamo Y
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Lumbar Degenerative Kyphosis (LDK) is a clinical entity showing kyphosis in the lumbar spine in elderly with multilevel disc narrowing and a varied degree of osteoporosis. LDK patient complains of stooped gait with persistent low back pain and weakness. Purpose of this paper is to study the lumbar muscle in LDK patients with histopathologic and biophysical evaluations to investigate the pathogenesis.

Materials and Methods: 1. Intramuscular pressure (IMP) (a) of the lumbar extensor compartment and hemoglobin content (Hb)□@(b) of 25 young volunteers were also investigated comparing in standing upright and flexion positions using (a)□@pressure monitoring kits and an non-invasive oxygenation monitor. 2.Muscle biopsy specimens obtained from the lumbar extensors of 9 LDK patients were histopathologically examined with HE, cytochrome c oxidase and other methods. These data were compared with muscles taken from age-match controls. Mitochondria function was also examined on biochemistry.

1. IMP of the extensors markedly increased in the flexion position (130.0□}45.4 in males and 86.3 mmHg in fem.) comparing to straight upright□@(22.8□}14.4, 17.0□}6.0). Oxy-Hb concentration decreased from 100% to 92.9, 95.5 % respectively in flexion, which was a sign of ischemia. 2. Both multifidus and sacrospinalis m. showed moderate to marked interstitial fibrosis, decreased number of muscle fibers and decreased stain intensity of cytochrome c oxidase. These finding were similar to those seen in repeatedly compressed muscles of an animal model of the chronic compartment syndrome. In comparison the rectus abd. and psoas muscles in the patients showed almost normal except for some aging changes. Conclusion: There appeared to be definite atrophy of the lumbar extensor muscles with histochemical and biochemical methods in LDK patients, whereas the flexors showed no change. This extensor atrophy is limited in the lumbar region in LDK. These localized atrophy of the lumbar extensors would suggest a result of high IMP during working in deep bending position of the spine for many years and may play important role in etiology of this disease condition.