Biomedical subjects

Hideki Warashina

Publications and source records attributed to Hideki Warashina.

8 recordsLinked to original sources

PubMed2005

Expression of inflammatory cytokines, RANKL and OPG induced by titanium, cobalt-chromium and polyethylene particles.

Bone resorption is regulated by cytokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1beta) and by the balance of a receptor activator of nuclear factor-kappaB ligand (RANKL) and osteoprotegerin (OPG). The aim of this study was to investigate the mechanism of particle-induced osteolysis in murine calvariae by assessing the extent of osteolysis and the expression of inflammatory cytokines, RANKL and OPG after implantation of metal and polyethylene particles. The murine calvariae implanted with Ti6Al4V, CoCr or high-density polyethylene (HDP) particles showed significantly more extensive osteolysis and elevated levels of inflammatory cytokines. The ratio between RANKL and OPG was high in the mice implanted with Ti6Al4V and HDP particles, but not in the mice implanted with CoCr particles. These observations suggested that CoCr particle-induced osteoclastogenesis may be caused directly by inflammatory cytokines rather than by the RANKL-RANK pathway. There might be different mechanisms at work in particle-induced osteolysis between Ti6Al4V, HDP and CoCr.

Animals↗

PubMed2004

The unstable total hip replacement.

Instability after total hip arthroplasty (THA) is not a rare occurrence. Numerous factors have been associated with dislocation including surgical approach, implant design, failure to restore proper hip mechanics and soft tissue restraints, and patient variables such as early postoperative compliance, soft tissue integrity, and neurologic conditions such as poor proprioception. A thorough understanding of the mechanism of dislocation, timing, and direction of dislocation is mandatory in formulating an approach toward treatment. The radiographic evaluation should evaluate hip mechanics including component orientation, adequacy of leg lengths, and restoration of offset in the frontal and sagittal planes. The treatment of the unstable total hip replacement is based on numerous variables including the timing of instability, direction, and mechanism. Instability in the early postoperative period in the hip with proper orientation and restored mechanics often is treated successfully with patient reeducation and use of adjunctive bracing. The treatment of the recurrent dislocator can be more difficult. Although reestablishing proper mechanics and orientation can be successful in many instances, some patients continue to have dislocation. Constrained acetabular liners have significantly improved the success rate of reducing the incidence of dislocation, but problems related to premature wear and dislodgement are a major concern. The use of larger articulating bearing surfaces used with the newer cross-linked polyethylene may provide the solution to instability minimizing the concerns related to constrained components.

Arthroplasty, Replacement, Hip↗

PubMed2003

Experimental evaluation of the usefulness of osteochondral allograft for articular cartilage defect.

This study was conducted to evaluate the usefulness of osteochondral allografts for articular cartilage defects. Cartilaginous defects measuring 4.5 mm in diameter were experimentally prepared in both the weight-bearing and non-weight-bearing regions of the femur in six male miniature pigs (9 months old). Osteochondral grafting was performed using fresh autografts (group AU), fresh allografts (group AL), or frozen allografts (group FA). Untreated cartilaginous defects were used as the control (group D). All the pigs were killed 4 weeks later, and the respective osteochondral grafts were macro- and microscopically evaluated. Hematoxylin and eosin staining, safranin O staining, and immunostaining [matrix metalloprotease-1 (MMP-1) and tissue inhibitor of metalloprotease-2 (TIMP-2)] were used for the histological evaluations of transplanted cartilage. Macroscopic and microscopic findings were assessed according to the criteria proposed by Wakitani et al. Although groups AU and AL showed similar median scores (ranges) for the evaluation of cartilaginous defect restoration, groups FA and D showed unfavorable scores: 3.9 (0-9) in group AU; 4.5 (0-12) in group AL; 10.2 (4-12) in group FA; and 7.0 (5-11) in group D. Immunostaining revealed almost identical results in groups AU and AL. As there were no histologically significant differences in the status of the osteochondral grafts between fresh autografts and fresh allografts, fresh allografts might be useful donor osteochondral grafts.

Animals↗

PubMed2003

Quality of life after several treatments for osteoarthritis of the hip.

The purpose of this study was to examine quality of life (QOL) after a rotational acetabular osteotomy (RAO), primary total hip arthroplasty (THA), or conservative treatment (Conservative). A series of 147 patients with osteoarthritis of the hip were grouped according to treatment into the RAO group ( n = 62), THA group ( n = 40), and Conservative group ( n = 45) (treated with medication and rehabilitation alone). The mean age of the RAO group was 40 years, the THA group 54 years, and the Conservative group 50 years. The mean follow-up periods were 3.6, 3.9, and 3.3 years, respectively. All patients were female. As a control group 609 volunteers participating in a town mass screening program were recruited. QOL was determined using the Nottingham Health Profile (NHP). Each area of QOL was evaluated separately in all of the treatment groups at less than 1 year after therapy, at more than 1 year but less than 5 years, and at more than 5 years. With regard to QOL at less than 1 year after therapy, the Conservative group had significantly higher scores for energy, pain, and emotional reaction than the Control group. With regard to physical mobility, all of the treatment groups showed significantly higher scores than the Control group. With regard to QOL at more than 1 year but less than 5 years, the RAO and THA groups showed significantly higher scores than the Control group regarding physical mobility. Regarding pain, the RAO and Conservative groups showed significantly higher scores than the Control group. With regard to QOL at more than 5 years, for physical mobility all of the treatment groups showed significantly higher scores than the Control group. For pain the RAO group showed significantly higher scores than the Control group. NHP is a useful means for evaluating QOL in patients treated for osteoarthritis of the hip.

Acetabulum↗

PubMed2003

Biological reaction to alumina, zirconia, titanium and polyethylene particles implanted onto murine calvaria.

Periprosthetic osteolysis is a serious problem that limits long-term survival of total hip arthroplasty. Ceramics have been introduced as a joint surface material to reduce osteolysis due to wear particles. The aim of this study is to investigate the biological reaction of ceramic particles on murine calvarial bone, in comparison with polyethylene and titanium particles. Sixty CL/BL6 mice were divided into five groups according to the materials implanted onto the murine calvariae: control, Al(2)O(3), ZrO(2), high-density polyethylene (HDP) and Ti6Al4V. One week after the implantation, each calvarial tissue was dissected and the release of proinflammatory mediators (IL-1beta, IL-6, TNF-alpha) and bone resorption were assessed. The particles of HDP and Ti6Al4V induced three and two times larger osteolytic lesions than the control, respectively. The levels of IL-1beta and IL-6 were significantly elevated in the medium subcultured with the calvariae of HDP and Ti6Al4V groups. Any particle type did not increase the levels of TNF-alpha. There were no significant differences observed in the levels of proinflammatory mediators or osteolytic area among Al(2)O(3), ZrO(2) and control groups. The inflammatory response and bone resorption induced by ceramic particles were much smaller than those induced by HDP and Ti6Al4V. These biological features suggest the biocompatibility of ceramics as a joint surface material for artificial joints.

Aluminum↗

PubMed2003

Early head penetration into cemented Hylamer Ogee socket.

The authors reviewed 18 consecutive cemented total hip arthroplasties with the Hylamer Ogee socket. The average follow-up period was 47 months. All Hylamer Ogee sockets were sterilized by gamma irradiation in air, and the average period from production to surgery was 12 months. Two-dimensional penetration of the femoral head into the Hylamer Ogee socket was determined from anteroposterior radiographs of the pelvis using a digitizer. The average head penetration rate of the present series was 0.36 mm/y. Osteolysis around both components was found in 6 cases (30%). Of 4 cases defined as aseptic loosening, 2 were revised during the follow-up period. To detect component loosening because of catastrophic high wear of the cemented Hylamer Ogee socket as early as possible, precise radiographic follow-up is essential.

Aged↗

PubMed2002

The long-term behavior of poly-L-lactide screws in a minipig fracture model: preliminary report.

The long-term degradation tissue response to poly-L-lactide (PLLA) screw was investigated for a minipig tibia fracture. As a bone-fracture model, three PLLA screws per animal were used to fix a tibia that had been subjected to a crank-shaped osteotomy. A total of 12 nine-month-old male minipigs were used. In time period from 1 month to 3 years, clinical, radiographic, and pathological studies were conducted. On macroscopic examination, no clear granuloma or fistula formation was noted for 3 years. On microscopic examination, no osteoclasts or giant cells were detected around the screws during the 3 years postoperatively. A substantial degradation of PLLA screw was observed between 2 and 3 years. At 3 years only slight residual breakdown products were found in macrophages. On electric microscopic examination, numerous degraded polymers were seen in a small number of macrophages around the screws. In this model, fixation of tibia fractures using PLLA screws was not associated with any side effects, and was safe and useful for up to 3 years.

Animals↗

PubMed2002

Total hip arthroplasty for a patient with angel-shaped phalango-epiphyseal dysplasia (ASPED). A case report.

Angel-shaped phalango-epiphyseal dysplasia is characterized by the angel shape of the middle phalanx and severe coxarthrosis in adult life. This osteochondrodysplasia shows a further variety of heterogeneous multiple epiphyseal dysplasias. It also shows a late and dysplastic development of the femoral head that leads to osteoarthrotic changes with severe hip pain and gait disturbance. In this report, we show a 35-year-old female with Angel-shaped phalango-epiphyseal dysplasia that was treated by bilateral total hip arthroplasty. She has suffered from her coxalgia since she was 27 and since the age of 30 has been able to walk with the aid of crutches. The radiographs of her bilateral hip showed severe osteochondrotic changes with a progressive disappearance of the joint space. Total hip arthroplasties were performed to treat the osteoarthrosis on the bilateral hip joint due to Angel-shaped phalango-epiphyseal dysplasia. One year after surgery, she is pain-free, and able to walk with a cane. Based on this case, we propose that total hip arthroplasty should be considered one of the treatments for the coxopathy in patients with Angel-shaped phalangoepiphyseal dysplasia.

Adult↗