Biomedical subjects

M Itoman

Publications and source records attributed to M Itoman.

44 records · Page 3Linked to original sources

PubMed1992

Valgus-flexion osteotomy for middle-aged patients with advanced osteoarthritis of the hip: a clinical and radiological evaluation.

We followed up 34 secondary osteoarthritis patients with 38 hips treated by valgus-flexion osteotomy between 1979 and 1985. The average age of the patients at surgery was 45 years and the follow-up period ranged from 5 to 11 years. After surgery, the clinical evaluations were made according to the JOA Hip Score which remained unchanged in all 38 hips for 5 years. After 6 years there were some hips whose score declined with time. It was found that the preoperative extension-flexion range was the factor that was most closely associated with the result of the surgery (p less than 0.01). Radiological examination at 5 years revealed that the joint space had been widely broadened and the trabecular structure nearly normalized in 23 hips (60.5%), while 15 hips (39.5%) showed a slight degree of joint space broadening and were left with sclerosis and pseudocysts. After a lapse of 10 years or more, in 13 hips out of 10 patients, seven were found to have osteoarthritic changes and revision had to be done by THR in 2 patients. Valgus-flexion osteotomy can therefore be said to provide one of the useful means to preserve joints when employed in middle-aged patients with secondary OA.

Adult↗

PubMed1991

Experimental study on allogenic bone grafts.

The effects of various processing techniques on the biomechanical properties and the histological incorporation of bone grafts were investigated in a rat model over a 6 month period. The stiffness of bone increased after freezing to -80 degrees C and freeze-drying. Decalcified bone was very soft. Visco-elasticity was pronounced at 4 to 12 weeks and the stiffness of the graft increased at 16 weeks. This progressive rise in stiffness was in line with the progressive incorporation of the graft. The bone incorporation ratio is proposed as a histological indicator of osteo-inductive properties. It was found to be best in fresh autografts, followed by processed allografts (frozen, freeze-dried and decalcified) and fresh allografts. The values of these 3 groups showed a statistically significant difference.

Animals↗

PubMed1991

Ganglion causing paralysis of the suprascapular nerve. Diagnosis by MRI and ultrasonography.

A 26-year-old man had a right infraspinatus muscle weakness and aching of the shoulder due to suprascapular nerve entrapment confirmed by electromyography. MRI revealed a well-defined area of increased signal intensity over the suprascapular notch. An ultrasonogram showed a homogeneous hypoechogenic area at the base of the scapular spine. A diagnosis was made of a ganglion compressing the inferior branch of the suprascapular nerve. After removal of several ganglia, the patient had immediate pain relief, and normal electromyographic findings were obtained 5 months postoperatively.

Adult↗

PubMed1988

Banked bone grafting for bone defect repair--clinical evaluation of bone union and graft incorporation.

One hundred and twenty-four banked bone grafts performed during the past 15 years were studied in respect to union and graft incorporation processes using X-ray, bone scintigraphy and histology. Radiological study of the chip graft showed an absence of cavity contours, and homogenization of the grafted area, followed by development of the trabecular structure. In the block graft, initial union was shown at the junctional area followed by the appearance of mottled shadows throughout the entire graft and finally differentiation of bone marrow and cortex. Bone scintigraphy showed an initial increase in RI uptake at the junction and then a gradual increase in the entire graft. Histological study showed that bone apposition on the trabeculae of the graft starts in the junction and later extends to other areas. The replacement of cancellous bone is more rapid than that of cortical bone. The porous surface seems to promote bone union and incorporation when large block grafts of cortical bone are used.

Bone Neoplasms↗

PubMed1988

Stable osteosynthesis by interlocking cylinder nailing for fractures of the femur and tibia.

Between 1979 and 1986, 140 patients with fractures of the femur and 94 with tibial fractures were treated with our own interlocking cylinder nail system and followed for 1 to 3 years. Overall, 97.9% of fractures of the femur and 93.6% of the tibia were found to have achieved excellent or good results clinically and radiologically. Complications included: delayed union which developed in 2 patients with femoral and tibial fractures and deep infection which developed in 3 of the tibial fractures. Even in highly comminuted fractures, the fracture site can be fixed securely with the interlocking cylinder nail system. Because mechanical strength of the cylinder nail is by far superior to that of the clover nail, the patient may be allowed early full weight bearing on his affected leg.

Bone Nails↗

PubMed1988

Aseptic necrosis of the femoral head supervening on systemic lupus erythematosus in identical twins--case report.

Identical twins who grew up in different environments from 100 days after birth developed systemic lupus erythematosus (SLE), followed later by aseptic necrosis of the femoral head (ANFH). Diagnosis of SLE was made in the younger sister (case 1) at age 14 and the elder (case 2) at 21 years of age. ANFH developed in these cases 5.9 and 1.2 years after the onset of SLE respectively. From some ovular identifications, they were diagnosed as being completely identical. These cases are of particular interest, since they suggest that hereditary factors are concerned with the development of ANFH to some degree.

Adolescent↗

PubMedDate not supplied

Progression of osteoporosis in cancellous bone depending on trabecular structure.

Progression of osteoporosis is caused by a decline in bone formation activity relative to the resorption activity. In this paper, the authors carried out a theoretical analysis of the progression of osteoporosis to estimate the osteoporotic change in the upper end of the femur. According to this analysis, the progression rate of osteoporosis in cancellous bone depends on the product of remodeling activity, Ract, and the trabecular structure parameter, Ktr. To confirm that the theoretical results were reasonably comparable to actual osteoporotic change, these two factors were measured in rabbits. From the results, it was concluded that the highest progression rate was shown in bar/bar-like trabecular structure (type 3); the next highest rate, was shown in plate/bar-like structure (type 2); and the plate/plate-like structure (type 1) was the most insensible. Furthermore, the bone volume fractions of cancellous bone were measured at the upper end of human femurs with and without osteoporosis. Then the measured value was compared with the theoretical value for each type of trabecular structure. Results showed that the decrease in bone volume fraction predicted by Eq. 7 was well in accord with the actual decrease.

Age Factors↗

PubMedDate not supplied

Percutaneous reduction of displaced radial neck fractures.

Twenty patients with acute, displaced, radial neck fractures were treated by percutaneous reduction with a periosteal elevator. In all cases acceptable radiographic reduction was achieved, and the reduction position was maintained on serial x-ray examinations with a mean observation period of 3 years. Clinical results were satisfactory in all but one case with slightly limited elbow extension.

Adult↗