Biomedical subjects

Mitsuo Ochi

Publications and source records attributed to Mitsuo Ochi.

151 records · Page 9Linked to original sources

PubMedDate not supplied

Relationship between osteochondritis dissecans of the lateral femoral condyle and lateral menisci types.

The purpose of this study was to examine the relationship between osteochondritis dissecans (OCD) of the lateral femoral condyle and lateral menisci. From 1993 to 2002, 38 knees (28 patients) were diagnosed with OCD of the lateral femoral condyle. OCD locations were graded by the Cahill and Berg classification. The types of lateral menisci were classified by Watanabe's classification. The relationship between OCD of the lateral femoral condyle and lateral menisci was examined. On the anterior-posterior view, 25 OCDs were located in zone 4 and 13 in zone 5. The types of lateral menisci were complete discoid in 19 knees, incomplete discoid in 15, and normal in 4. Ten of the 19 complete discoid menisci were damaged. Complete discoid menisci without tears were found in OCDs located in zone 4; incomplete discoid menisci were found in OCDs located in zone 5. The authors found a relationship between the type of OCD and the state of the lateral meniscus.

Adolescent↗

PubMedDate not supplied

Three-dimensional computed tomography imaging: its applicability in the evaluation of extensor tendons in the hand and wrist.

OBJECTIVE: The purpose of this study was to determine whether 3-dimensional (3D) computed tomography (CT) imaging with volume rendering can accurately evaluate extensor tendons in the hand and wrist. METHODS: Three-dimensional CT imaging was used to evaluate 14 cases. The location where the rupture was suspected was the wrist level in all cases. The accuracy of the image diagnosis was confirmed during surgery in 13 cases. RESULTS: Three-dimensional CT could identify all extensor tendons proximal to the metacarpophalangeal joint. In the cases with rupture, the location of the distal stump could be identified, whereas that of the proximal stump was uncertain. The tendon stump location confirmed during surgery correlated well with the images. CONCLUSIONS: This study revealed the usefulness of 3D CT imaging in defining extensor tendons proximal to the metacarpophalangeal joint. This method increased the accuracy and ease of diagnosis and was always useful in surgical planning and patient education.

Adult↗

PubMedDate not supplied

Three-dimensional computed tomography imaging evidence of regeneration of the semitendinosus tendon harvested for anterior cruciate ligament reconstruction: a comparison with hamstring muscle strength.

OBJECTIVE: The purpose of this study was to evaluate the regeneration of semitendinosus tendons harvested for anterior cruciate ligament (ACL) reconstruction using 3-dimensional (3D) computed tomography (CT) imaging and to compare the degree of regeneration with hamstring strength. METHODS: Twenty-nine patients who underwent ACL reconstruction using ipsilateral autogenous semitendinosus tendons were examined before surgery and 6 and 12 months after surgery by 3D CT imaging. The types of regenerated tendons and the proximal shift of the muscle-tendon junction were evaluated. RESULTS: The types of regenerated semitendinosus tendons varied from case to case. There was a positive correlation between the peak torque ratio of the hamstring muscle strength and the proximal shift of the muscle-tendon junction 6 months after surgery. The proximal shift did not affect the peak torque ratio 12 months after surgery, however. CONCLUSIONS: A proximal shift of the muscle-tendon junction may help to explain the individual differences in early postoperative hamstring muscle strength recovery.

Adolescent↗

PubMedDate not supplied

Determination of time of biologic fixation after anterior cruciate ligament reconstruction with hamstring tendons.

BACKGROUND: It has been unclear when a hamstring tendon graft becomes biologically fixed in the bone tunnel after anterior cruciate ligament reconstruction. HYPOTHESIS: Postoperative biomechanical testing and magnetic resonance images can indicate biologic fixation of the graft in the femoral bone tunnel. STUDY DESIGN: Prospective cohort study. METHODS: Sixty-four patients were evaluated by serial biomechanical testing, magnetic resonance imaging, and second-look arthroscopy 2 years after surgery. Biologic fixation of the graft was confirmed radiographically by injecting a contrast medium into the femoral bone tunnel. RESULTS: Forty-two stable knees with graft fixation maintained a high stiffness (120% of normal) and showed low signal intensity in an early postoperative magnetic resonance image (12 +/- 8 months). Fourteen stable knees without graft fixation had gradually increased anterior displacement with nearly normal stiffness and high signal intensity. Five unstable knees with graft fixation retained low stiffness (70%) and showed late low signal intensity at 20 +/- 9 months. Three unstable knees without biologic fixation had rapidly increased anterior displacement, with half the stiffness of a normal knee. CONCLUSION: Postoperative low stiffness and high signal intensity might indicate late biologic graft fixation, predicting a possibility of postoperative anterior knee instability.

Adolescent↗

PubMedDate not supplied

Acetabular osteosarcoma treated by irradiation-vascularized hybrid bone graft.

BACKGROUND: Periacetabular reconstruction after malignant bone tumor resection to preserve limb function is extremely challenging. The optimal reconstruction method has not yet received consensus and the functional outcomes still remain unsatisfactory. CASE REPORT: A thirteen-year-old girl who was suffering from acetabular osteosarcoma was treated with wide excision of the tumor, followed by periacetabular reconstruction with an autogenous extracorporeal irradiated osteoarticular graft combined with a vascularized fibula graft. Incorporation of the irradiated pelvic bone was achieved despite infection and limb function turned out to be acceptable. CONCLUSION: This is the first report on an irradiation-vascularized hybrid autograft to reconstruct massive bone loss in primary limb-sparing surgery.

Acetabulum↗

PubMedDate not supplied

Histological findings in a human autogenous pasteurized bone graft.

BACKGROUND: Autogenous bone graft after pasteurization is one of the most valuable procedures for reconstruction of large bone defects following excision of malignant musculoskeletal tumors. To date, there have been no documented histological reports on pasteurized bone grafts, apart from short-term histological results. CASE REPORT: We treated a 27-year-old male with a periosteal chondrosarcoma of the tibia by wide excision and reimplantation of the large pasteurized bone. Biopsy specimens harvested from the pasteurized bone over 3 years after reimplantation were evaluated histologically. The graft cortices remained totally necrotic with empty osseous lacuna, whereas the architecture of the acellular cortical bones was still maintained without microfractures. Deposited seams of woven bone existed focally on the surface of the acellular trabeculae. CONCLUSION: Our medium-term histological outcome suggests the limitations of incorporating a pasteurized hone graft, but also advocates its role as a useful temporary material for the reconstruction of massive bone defects.

Adult↗

PubMedDate not supplied

Postradiation malignant fibrous histiocytoma and osteosarcoma of a patient with high telomerase activities.

BACKGROUND: An extremely rare case of postradiation malignant fibrous histiocytoma (MFH) and osteosarcoma (OS) secondary to radiation therapy for leukemia-related osteolytic lesions is presented. In addition, the telomere biology of these tumors was investigated. CASE REPORT: A 14-year-old boy was diagnosed with acute lymphocytic leukemia. The right tibia was irradiated at a total dose of 60 Gy, and the left tibia was irradiated at a total dose of 40 Gy. The left tibia developed MFH and the right tibia developed OS. RESULTS: Telomere reduction (MFH 70.2, OS 70.0%) and high telomerase activities (MFH 12.1, OS 17.7 TPG) were observed. These results reflect an aggressive feature of postradiation sarcomas. CONCLUSION: Prognosis for patients diagnosed with postradiation sarcoma is poor due to its aggressiveness. However, even if sarcoma occurs after irradiation in more than two fields in a single patient, improvements in prognosis are anticipated with appropriate chemotherapies and wide resection.

Adolescent↗