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Akihiro Sudo

Publications and source records attributed to Akihiro Sudo.

15 recordsLinked to original sources
PubMed2006

Effect of tourniquet application on deep vein thrombosis after total knee arthroplasty.

INTRODUCTION: There is a great deal of controversy about the effect of tourniquets on development of deep vein thrombosis (DVT) after total knee arthroplasty (TKA). PATIENTS AND METHODS: We investigated the incidence of postoperative DVT after TKA with or without the use of a tourniquet. The patients were 48 consecutive patients undergoing primary ipsilateral cemented TKA for osteoarthritis. Group A (21 patients) underwent the operation without a tourniquet, and Group B (27 patients) underwent the operation with a tourniquet. Ultrasonography to assess DVT was performed before and after the operation. RESULTS: Group B had less intraoperative and total blood loss than Group A. Postoperative DVT was detected in 81.3% of all cases, and symptomatic pulmonary embolism occurred in 1.7%. Most of DVT was found in the calf vein. There was no significant difference in the incidence of postoperative DVT between the two groups. CONCLUSION: We conclude that the use of a tourniquet is beneficial, because it decreases perioperative blood loss and does not increase the risk of DVT. The incidence of DVT after TKA is considerably high with or without use of a tourniquet. Therefore, prevention and early detection of DVT are important for prevention of fatal pulmonary thromboembolism.

Aged↗
PubMed2006

Dislocation of posterior-stabilized mobile-bearing knee prosthesis. A case report.

Spin-out of mobile-bearing knees is a significant early complication of mobile-bearing total knee arthroplasty. Dislocation of the cam-post mechanism of fixed-bearing posterior-stabilized knees occurs more rarely. We have observed an unusual case of dislocation of posterior-stabilized rotating-platform total knee arthroplasty, which has both a cam-post mechanism and rotating platform. A 65-year-old man with knee osteoarthritis and cervical spondylotic myelopathy underwent total knee arthroplasty using a mobile-bearing prosthesis. The dislocation, which occurred 4 days postoperatively, could not be reduced by closed manipulation. However, spontaneous reduction occurred 6 days after the dislocation, which did not recur. A gap mismatch or trapezoidal-shaped gaps may lead to dislocation or spin-out of the bearing insert. This case illustrates that dislocation of a posterior-stabilized mobile-bearing total knee arthroplasty can occur, and both quadriceps deficiency and ligament laxity may contribute to the risk of dislocation.

Aged↗
PubMed2006

A large metallic cyst caused by wear particles after total knee arthroplasty.

INTRODUCTION: A symptomatic cyst is an uncommon complication after total knee arthroplasty (TKA). We present a case of a 77-year-old woman with a large cyst in the right knee caused by metal wear debris from the failure of a Miller-Galante I TKA performed 13 years earlier. CASE PRESENTATION: The patient was treated with a two-stage operation including revision of the TKA followed by excision of the cyst, because there was a direct communication between the joint cavity and the cyst, and because the patient reported pain corresponding to the cystic area after revision. The patient was pain-free and had a satisfactory result 17 months after the second operation, without recurrence of cyst formation. CONCLUSION: We recommend two-stage surgery in which the first-stage is correction of the intra-articular pathology with revision TKA and the second-stage is excision of the cyst.

Aged↗
PubMed2006

Bilateral hip fractures.

BACKGROUND: In the past, patients admitted for hip fractures had often sustained a contralateral hip fracture. The incidence of bilateral hip fractures has been reported to be 5%-10%, and in the future the number of bilateral hip fractures is expected to increase with the increase of unilateral hip fractures. We believe that bilateral hip fractures can be efficiently prevented if a fracture on the other side could be predicted after unilateral hip fracture. Therefore, this retrospective study of 835 patients with hip fractures investigated the incidence, prognosis, and risk factors of bilateral hip fractures. METHODS: We examined 835 hip fractures retrospectively in Japan. Among them, we found 94 patients with bilateral noncontemporary hip fractures. We investigated age, sex, interval between the two fractures, type of fractures, cause, physical functioning, and complications. Differences between the unilateral fracture and bilateral fractures groups were analyzed statistically for age, sex, and complications using Student's t test and the chi-square test. RESULTS: In this study, the mean interval between two fractures was 4.28 years, and the second hip fracture occurred within 5 years in more than 70% of patients. The type of hip fracture was the same in 72.2% of bilateral hip fractures. No difference in age and sex was found between the unilateral and the bilateral groups. However, concerning complications, 22.1% of patients in the unilateral group and 34.8% in the bilateral group had dementia, the difference being significant. CONCLUSIONS: These results revealed that the second hip fracture occurred within 5 years of the first in more than 70% of bilateral hip fracture patients and that dementia is a risk factor of bilateral hip fractures.

Accidental Falls↗
PubMed2006

Computed tomographic evaluation of component position on dislocation after total hip arthroplasty.

True proper position after total hip arthroplasty was determined by measuring the cup and stem anteversion using computed tomography. We compared 20 dislocated hips (14 posterior and 6 anterior) with 18 non-dislocated hips. Both the cup anteversion and the stem anteversion showed no differences among the groups. The sum of cup and stem anteversion in posterior dislocated hips was significantly lesser than that in non-dislocated hips and the sum in anterior dislocated hips was significantly greater than that in non-dislocated hips. These results suggested even if the cup alone or the stemalone is at proper position, dislocation might occur.

Aged↗
PubMed2005

Rapidly destructive coxopathy after subchondral insufficiency fracture of the femoral head.

Rapidly destructive coxopathy (RDC) is a rare disorder, and its pathophysiology is unknown. Here, we report a case of RDC evaluated by roentgenography and magnetic resonance imaging, from the onset of hip pain without changes on roentgenograms, to the terminal stage with collapse of the femoral head. Our serial radiological findings clearly illustrate the entire process of RDC, especially the initial stage. Subchondral insufficiency fracture of the femoral head seems to be an important preliminary event in the development of RDC.

Aged↗
PubMed2005

An aspartic acid repeat polymorphism in asporin inhibits chondrogenesis and increases susceptibility to osteoarthritis.

Osteoarthritis is the most common form of human arthritis. We investigated the potential role of asporin, an extracellular matrix component expressed abundantly in the articular cartilage of individuals with osteoarthritis, in the pathogenesis of osteoarthritis. Here we report a significant association between a polymorphism in the aspartic acid (D) repeat of the gene encoding asporin (ASPN) and osteoarthritis. In two independent populations of individuals with knee osteoarthritis, the D14 allele of ASPN is over-represented relative to the common D13 allele, and its frequency increases with disease severity. The D14 allele is also over-represented in individuals with hip osteoarthritis. Asporin suppresses TGF-beta-mediated expression of the genes aggrecan (AGC1) and type II collagen (COL2A1) and reduced proteoglycan accumulation in an in vitro model of chondrogenesis. The effect on TGF-beta activity is allele-specific, with the D14 allele resulting in greater inhibition than other alleles. In vitro binding assays showed a direct interaction between asporin and TGF-beta. Taken together, these findings provide another functional link between extracellular matrix proteins, TGF-beta activity and disease, suggesting new therapeutic strategies for osteoarthritis.

Aggrecans↗
PubMed2005

Enhanced repair of large osteochondral defects using a combination of artificial cartilage and basic fibroblast growth factor.

The purpose of this study was to examine the efficacy of a combination of artificial cartilage and basic fibroblast growth factor (bFGF) for the repair of large osteochondral defects. The artificial cartilage was a three-dimensional fabric (3-DF) composed of an ultra-high molecular weight polyethylene fiber with a triaxial three-dimensional structure. We implanted 3-DF impregnated with type I collagen gel containing 500 ng of bFGF (bFGF-treated group) or 3-DF impregnated with type I collagen gel alone (non-treated group) into a large full-thickness osteochondral defect (6 x 6 x 3 mm) of the patellar groove of rabbits. The defect area was examined grossly, histologically and biomechanically 4-48 weeks after surgery. Bone ingrowth into and around the 3-DF was evaluated with micro-computed tomography (micro-CT). Addition of bFGF to the 3-DF greatly accelerated cartilage formation on the articular surface and subchondral bone formation into and around the 3-DF, and improved biomechanical properties. These findings suggest that a combination of artificial cartilage and bFGF is clinically useful in cases involving large osteochondral defects.

Animals↗
PubMed2004

High release of antibiotic from a novel hydroxyapatite with bimodal pore size distribution.

We developed a novel hydroxyapatite (HA) cylinder (HA-A) and compared the slow release of antibiotic in vitro as well as osteoconduction of the material in vivo to a commercially produced porous hydroxyapatite cylinder (HA-B). HA-A (4 x 4 mm) was synthesized by mixing HA powder, gelatin, and vegetable oil. The material had a bimodal pore size distribution, with intragranular (10 nm to 10 microm) and intergranular (100 microm) pores, and porosity of 40 vol %, while HA-B had pore sizes ranging from 50 to 300 microm and identical porosity. In vitro drug release was tested using antibiotics (isepamicin sulfate, vancomycin hydrochloride, and flomoxef sodium) soaked on the HA cylinders using a vacuum system. The mean adsorption efficiency was higher for HA-A (46%) than for HA-B (26%) and higher levels of antibiotic were released from HA-A. Of the antibiotics, ISP showed the longest release duration. Bone ingrowth into the pores was observed for both materials. Because the novel HA showed both the slower release of antibiotic (nanosize pores) and supported excellent osteoconduction (microsize pores), it could be useful for the treatment of osteomyelitis.

Adsorption↗
PubMed2004

Disassembly of bipolar cup with self-centering system: a report of seven cases.

Disassembly of bipolar cups with a self-centering system occurred in six patients (seven hips; five women, one man) and the cause of the failure was evaluated. The mean age of the patients at the time of arthroplasty was 49.7 years (range, 27-85 years), and mean weight was 48.4 kg (range, 37-65 kg). The mean time to failure was 7.5 years (range, 4.8-9.2 years). Before failure, all implants functioned well and none of the patients had sustained trauma. Retrieval study showed that the cause of failure of the locking mechanism with a self-centering system was severe polyethylene abrasion at the rim attributable to impingement and deformity of the locking ring. After the locking ring detached, the inner head dislocated from the outer head resulting in a varus position of the outer head in the acetabulum. If the deformed locking ring did not detach, the inner head could dislocate, with the varus outer head remaining in the acetabulum. The incidence of this failure was 11%. This disassembly is not a rare occurrence numerous years after a well-functioning bipolar hemiarthroplasty, even with the self-centering system.

Adult↗
PubMed2004

Tenascin-C concentration in synovial fluid correlates with radiographic progression of knee osteoarthritis.

OBJECTIVE: Osteoarthritis (OA) is a major cause of disability and represents the most common disease in the aging population. Although the course of the disease is generally assessed using standard radiographic images, biochemical markers may be employed to detect the disease and determine the degree of severity. We developed an enzyme linked immunosorbent assay (ELISA) system using a monoclonal antibody specific for the large-splice variants of tenascin-C (TN-C) and examined whether TN-C in synovial fluid (SF) is an adequate biochemical marker of OA progression. METHODS: SF samples were obtained from knees of 74 patients with OA and 16 without OA. Based on the radiographic grading of the OA severity, the knees were divided into 3 groups: mild, moderate, and severe OA. Expression of TN-C splice variants was examined using immunoblotting. TN-C concentrations were determined by ELISA. RESULTS: Western blotting showed the presence of large TN-C variants in SF from severe OA. TN-C levels were 5-fold higher in OA samples compared to subjects without OA (p < 0.0001). TN-C levels were not different between control cases and mild OA, but increased significantly in moderate (p = 0.0244) and severe OA (p < 0.0001). After adjusting TN-C levels for age, body mass index, and sex, TN-C levels correlated with radiographic progression of knee OA (R2 = 0.404, p < 0.0001). CONCLUSION: TN-C, including the large-variant subunits, is a useful biochemical marker for OA progression in the later stages of disease.

Adolescent↗
PubMed2003

Ceramic acetabular liner fracture in total hip arthroplasty with a ceramic sandwich cup.

In total hip arthroplasty, a modular acetabular component with a sandwich insertion (alumina ceramics/polyethylene/titanium) was proposed. The polyethylene layer might reduce the rigidity of the ceramics and prevent an impingement between the ceramic liner rim and the femoral neck. A case of an acetabular liner fracture of the ceramic sandwich cup was presented. The fracture occurred 1.4 years after the operation without trauma. Because the ceramic liner rim was hit by the head following the impingement between the neck and the polyethylene, the cause of the fracture might be the stress concentration at the rim of the ceramic liner, of which the thickness was only 4 mm. At revision surgery, the fractured ceramic liner was replaced with a polyethylene liner without inner ceramic liner.

Aluminum Oxide↗
PubMed2002

Effect of hyperthermia by magnetite cement on tumor-induced bone destruction.

Our study focuses on the antineoplasmic action of hyperthermia. In this study, use of a heat-generating cement was exploited for the management of pathological and impending fractures in malignancies. The cement contains magnetic powder in ceramic particles and generates well-regulated heat when a magnetic field is applied externally. Eighteen rabbits were inoculated with blocks of VX2 tumor into one of their tibia. One week after the procedure, 9 rabbits were exposed to a magnetic field (HT group) while the remaining 9 rabbits were not (non-HT group). In rabbits killed between 20 and 42 days after the VX2 inoculation, the circumference of the operated leg was 7.9 +/- 0.3 cm and 10.2 +/- 1.0 cm (mean +/- SE) in HT and non-HT groups, respectively ( P < 0.05). Histological findings revealed the regressive change in tumor tissue of the HT group. By radiographs, pathological fractures and cortical bone destruction were seen in 5 and 8 rabbits in the non-HT group, respectively, but in the HT group these effects were absent in all the rabbits except 1 in which a definite diagnosis has not been made. Our findings demonstrate that controlled hyperthermia therapy using a newly developed bone cement suppresses tumor growth and prevents local bone destruction caused by VX2 tumors.

Animals↗
PubMed2002

Human osteosarcoma-derived cell lines produce soluble factor(s) that induces differentiation of blood monocytes to osteoclast-like cells.

When monocytes were cocultured with human osteosarcoma-derived cells (HOS cells), multinucleated giant cell formation of monocytes was induced. Intriguingly, even when a filter was interposed between monocytes and HOS cells, polykaryocytes also appeared. The multinucleated giant cells have characters similar to osteoclast-like cells. These findings indicate that soluble factor(s) secreted from HOS cells play an important role in polykaryocyte formation from monocytes. Twelve cloned cells were established from HSOS-1 cells and their capacities of inducing osteoclasts were investigated. Three cloned cells inducing nos. 4 and 9 had an ability of inducing osteoclasts (multinucleated giant cells, TRAP, calcitonin receptor and c-src mRNAs, osteoresorbing activity), and three cells, including nos. 1 and 5, did not show the ability. HOS cells and the cloned cells expressed several cytokine mRNAs. M-CSF was detected in the culture fluids of HOS cells, which also expressed RANK and RANK/ODF/OPGL mRNAs. Intriguingly, HOS cells secreting a soluble osteoclast inducing factors(s) expressed TNF-alpha converting enzyme mRNA. Furthermore, OCIF/OPG inhibited HOS cell-induced osteoclastogenesis and soluble RANKL could be detected in the culture fluids of HOS cells expressing TACE, suggesting that one of soluble osteoclast-inducing factor(s) is soluble RANKL. When blood monocytes were indirectly cocultured with HSOS-1 cells or cloned no. 9 cells in the presence of OCIF for 14 days, HOS cell-mediated osteoclastogenesis was suppressed, indicating that RANK-RANKL system is involved in the HOS cell-mediated osteoclastogenesis.

Acid Phosphatase↗