Biomedical subjects

T U Jiya

Publications and source records attributed to T U Jiya.

5 recordsLinked to original sources

PubMed2001

Polyurethane real-size models used in planning complex spinal surgery.

STUDY DESIGN: The application of polyurethane real-size models for planning and performing complex spinal surgery is described. OBJECTIVE: To determine the feasibility of using polyurethane real-size models to plan osteotomies, resections, and designs of custom-made spinal implants in complex spinal surgery. SUMMARY OF BACKGROUND DATA: In selected patients with complex spinal pathology, exact planning of the surgical procedure is not possible using current imaging methods. In these cases, real-size spinal models would be desirable to enhance pre- and perioperative planning by visual and tactile feedback, and to improve the production of custom-made spinal implants. METHODS: A real-size spinal model of six patients was produced from hardened polyurethane foam on the basis of data from contiguous computer tomography slices. In two patients, the models were used to plan correction osteotomies and resections, with the assistance of image-guided surgery in one of the patients. In four patients, the models were used to plan tumor resections and to produce custom-made spinal implants. RESULTS: In all the patients, the surgical procedure could be performed exactly according to the preplanned intervention. The polyurethane real-size models provided essential and additional information by direct visual and tactile feedback. They allowed in vitro testing of custom-made spinal implants with a perfect fit. CONCLUSIONS: Real-size spinal models made from polyurethane foam can be used to provide excellent understanding of the complex spinal pathology in highly selected patients. These models allow complex spinal surgery with a more predictable outcome.

Adolescent↗

PubMed1999

Free vascularized bone graft in spinal surgery: indications and outcome in eight cases.

In selected spinal deformities the use of a vascularized graft to establish fusion may be considered: compared to a non-vascularized graft it has superior mechanical properties, resulting in greater graft strength and stiffness, and greater effectiveness in facilitating union. Eight patients with a progressive spinal deformity (four cases) and malignancy (four cases) were treated with resection and/or correction and stabilization. To facilitate (multi)level fusion vascularized fibular grafts were used in two cervical and two thoracolumbar deformities. Fibular (two cases) or iliac grafts (two cases) were used in four cases of spinal reconstruction after vertebrectomy for malignancy. In all patients complete incorporation of the graft was obtained within 5 weeks to 8 months postoperatively. Complications occurred in three cases: one patient had a transient laryngeal edema and laryngeal nerve palsy. Another patient had a non-fatal deep vein thrombosis with pulmonary embolisms, successfully treated with anticoagulants. A third patient developed a lung infection and subsequently a deep infection around the dorsal instrumentation; after hardware removal the infection was controlled. At the latest follow-up (mean 30 months, range 24-48 months) six out of eight patients are alive. One patient died 2.5 years after the intervention due to widespread metastases, while another patient died in the postoperative period due to unknown reasons. Vascularized bone graft in spinal surgery facilitates primary mechanical stability and rapid fusion, and it has higher resistance to infection. The variety of applications of a vascularized graft may extend the range of indications for the use of grafts in spinal surgery.

Adolescent↗

PubMed1999

Histopathology of retrieved allografts of the femoral head.

From November 1994 to March 1997, we harvested 137 grafts of the femoral head from 125 patients for donation during total hip arthroplasty according to the guidelines of the American Associations of Tissue Banks (AATB) and the European Association of Musculo-Skeletal transplantation (EAMST). In addition to the standards recommended by these authorities, we performed histopathological examination of a core biopsy of the retrieved bone allograft and of the synovium. Of the 137 allografts, 48 (35.0%) fulfilled all criteria and were free for donation; 31 (22.6%) were not regarded as suitable for transplantation because the serological retests at six months were not yet complete and 58 (42.3%) were discarded because of incomplete data. Of those discarded, five showed abnormal histopathological findings; three were highly suspicious of low-grade B-cell lymphoma, one of monoclonal plasmacytosis and the other of non-specific inflammation of bone marrow. However, according to the standards of the AATB or EAMST they all met the criteria and were eligible for transplantation. Our findings indicate that the incidence of abnormal histopathology in these retrieved allografts was 3.6%. Since it is essential to confirm the quality of donor bones in bone banking, we advise that histopathological screening of donor bone should be performed to exclude abnormal allografts.

Adult↗

PubMed1998

Lumbar intervertebral disc involvement in chronic lymphocytic leukemia. A case report.

STUDY DESIGN: Report of a patient with a rare location of a solid chronic lymphocytic leukemic mass of an intervertebral lumbar disc. OBJECTIVES: To illustrate the previously undescribed discovertebral involvement of chronic lymphocytic leukemia and to discuss the diagnostic difficulties. SUMMARY OF BACKGROUND DATA: Chronic lymphocytic leukemia primarily involves lymph nodes, spleen, liver, and bone marrow. Bone lesions are rare in chronic lymphocytic leukemia and usually consist of areas of osteopenia. Spinal involvement in chronic lymphocytic leukemia is rare, and only two cases of spinal cord compression attributable to an extradural solid mass composed of leukemic cells have been reported. Intervertebral disc involvement in chronic lymphocytic leukemia has not been reported previously. METHODS: The clinical findings, radiographs, histology, treatment, and follow-up results are presented. RESULTS: Radiographs and magnetic resonance imaging studies showed partial collapse of vertebrae L2 and L3, with destruction and protrusion of the intervertebral disc L2-L3 with dura compression. Treatment consisted of radiotherapy followed by en bloc resection of vertebrae L2 and L3 stabilized with stackable cages and anterior fixation with Kaneda bars. Intervertebral disc infiltration with leukemic cells of B-cell origin was confirmed through histologic examination and immunohistochemical studies of a biopsy and resection specimen. Twenty months after treatment the patient was still in remission and fully mobilized. CONCLUSIONS: Intervertebral disc involvement in cases of chronic lymphocytic leukemia is rare. Its presence should be considered in patients with back pain and neurologic symptoms who had been treated for this form of leukemia in the past. Differentiation with infectious spondylodiscitis can be difficult. Histology is necessary to confirm diagnosis.

Aged↗

PubMed1997

Surgical treatment of wrist deformity in hereditary multiple exostosis.

Wrist deformity represents a unique problematic entity in patients with Hereditary Multiple Exostosis (HME). We report our experience in the treatment of wrist deformities due to HME using three surgical procedures and the outcome of 12 wrist surgical corrections by comparing preoperative, postoperative and last follow-up radiographic values of the carpal slip, radial articular angle and ulnar shortening. Eight out of 12 forearms did show a postoperative improvement of the radiographic parameters, although recurrence of the deformity occurred frequently. Two forearms showed no change in postoperative radiologic parameters. The average age at operation was 13 years, 4 months and the average duration of follow-up was 76.1 months. Prevention and reducing the progression of deformity and functional disability is an important goal in the management of these patients. The type of deformity is the most important factor in deciding the type of surgery to be performed.

Adolescent↗