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Biomedical subjects

Masahito Hatori

Publications and source records attributed to Masahito Hatori.

At least 37 records · Page 2Linked to original sources

Operative treatment by external fixation for polyostotic fibrous dysplasia in the elbow joint. A case report.

Fibrous dysplasia is a condition in which normal skeletal bone changes into fibroblastic stroma and immature bone. We report our experience of a unilateral external fixator applied for the treatment of polyostotic fibrous dysplasia arising in the elbow. The patient was a 38 year-old man. His main complaint was left elbow pain and a mass, which increased in size. The histological diagnosis from the needle biopsy was fibrous dysplasia. An articulated unilateral external fixator was used for immobilization. The lesions in the left distal humerus and proximal ulna were curetted and cancellous bone was packed into the cavity. An external fixator (Elbow Fixator, Orthofix Inc., McKinney, USA) was applied from the proximal humeral shaft to the distal ulnar shaft for postoperative tentative immobilization and preservation of the affected elbow joint movement. At two years after the operation, the range of motion of the affected elbow was 90 degrees in flexion and -35 degrees in extension. The range of motion in pronation and supination of the left forearm was normal. No evidence of recurrence was noted at two years after surgery. The merits of using an external fixator were: an earlier start of range of motion exercises, and a decrease in the risk of tumor dissemination.

Adult↗

Fatigue fracture of the distal femur arising in the elderly.

Fatigue fractures most frequently involve the tibia and metatarsal bones in the young. We report a very unusual case of fatigue fracture in the distal femur of a 62-year-old man. The differential diagnosis was a pathological fracture due to a metastatic bone tumor. The diagnosis of fatigue fracture was based on the fact that the patient walked every day for a long time, together with the following radiological features: no definite cortical destruction, a radiolucent area surrounded by sclerosis on CT, no extraskeletal mass, and sharp linear low signal intensities in the center of the lesion on MR images. Rest and restricted walking improved his symptoms and fracture healing. Fatigue fracture should be ruled out even in the elderly, especially those who engage in sports activities for long periods.

Age Factors↗

Talar fractures associated with ipsilateral femoral shaft fractures: report of three cases.

Talar fractures associated with ipsilateral femoral shaft fractures have been occasionally reported, but an unexpectedly high potential for simultaneous occurrence of the fractures in head-on collisions has not been well documented. We treated three patients with ipsilateral femoral shaft and talar fractures in a 2-year period starting in 2000. The patients were male, aged 25, 34 and 40 years, polytraumatized with other injuries. In all cases, the fractures occurred in the right lower extremities of drivers involved in head-on collisions. The talar fractures were not detected at the initial diagnosis. We considered that the feet had been dorsiflexed and exposed to an axial load from the front when the drivers pushed the brake pedals. This condition was considered to cause both fractures. Careful examination should be carried out to rule out talar fractures in swollen feet associated with femoral shaft fractures in head-on collisions.

Accidents, Traffic↗

Clinical results in severe carpal tunnel syndrome and motor nerve conduction studies.

The purposes of this study were to assess the value of motor nerve conduction studies as a prognostic indicator for severe carpal tunnel syndrome (CTS) and to investigate residual nerve disorder after surgery. Fifty hands in 46 patients with severe CTS were followed for at least 6 months after surgery for open carpal tunnel release. Compound muscle action potential (CMAP) from the abductor pollicis brevis (APB) muscle and the second lumbrical (SL) muscle were recorded before and after surgery, and distal latency (DL) and amplitude were analyzed. APB-CMAP was not recordable in 43 hands while SL-CMAP was recordable in all 50 hands before surgery. Results were excellent in 28 hands, good in 16 hands, fair in 6 hands, with no poor results after surgery. The ratio of excellent result was 65% in patients in whom DL of preoperative SL-CMAP was less than 10 ms, and 20% in patients whose DL was 10 ms or more. Delayed DL was seen in postoperative APB-CMAP and SL-CMAP, especially in the patients with good or fair results. We consider that SL-CMAP was valuable as a prognostic indicator for severe CTS, and if DL was 10 ms or more, myelinization of fibers would not be sufficient after surgery.

Action Potentials↗

Development and reliability of a standard rating system for outcome measurement of foot and ankle disorders I: development of standard rating system.

BACKGROUND: The aim of this study was to report the five scales comprising the rating system that the Japanese Society for Surgery of the Foot (JSSF) devised (JSSF standard rating system) and the newly offered interpretations and criteria for determinations of each assessment item. METHODS: We produced the new scales for the JSSF standard system by modifying the clinical rating systems established by the American Orthopaedic Foot and Ankle Society (AOFAS scales) and the Japanese Orthopaedic Association's foot rating scale (JOA scale). We also provided interpretations of each assessment item and the criteria of determinations in the new standard system. RESULTS: We improved the ambiguous expressions and content in the conventional standard rating systems so they would be easily understood by Japanese people. The result was five scales in total. Four were designed for use specifically for ankle-hindfoot, midfoot, hallux metatarsophalangeal-interphalangeal, and lesser metatarsophalangeal-ineterphalangeal sites; and the fifth was for the foot and ankle with rheumatoid arthritis. Furthermore, we described interpretations and criteria for determinations with regard to evaluation items in each scale. CONCLUSIONS: Conventionally, the AOFAS scales or the JOA scale have been separately applied depending on the sites or disorders concerned, but it was often difficult to decide on scores during practical evaluations because of differing expressions in different languages and also because of ambiguity in the interpretation of each evaluation item and in scoring standards as well. JSSF improved these scales and added definite interpretations of evaluation items as well as criteria for the rating (to be reported here in part I). Because these steps were expected to improve the reliability of outcomes assessed by each scale, we examined the reliability in scores of the newly developed scales, which are reported in part II (in this issue).

Ankle↗

Development and reliability of a standard rating system for outcome measurement of foot and ankle disorders II: interclinician and intraclinician reliability and validity of the newly established standard rating scales and Japanese Orthopaedic Association rating scale.

BACKGROUND: This study evaluated the validity and inter- and intraclinician reliability of (1) the Japanese Society of Surgery of the Foot (JSSF) standard rating system for four sites [ankle-hindfoot (AH), midfoot (MF), hallux (HL), and lesser toe (LT)] and the rheumatoid arthritis (RA) foot and ankle scale and (2) the Japanese Orthopaedic Association's foot rating scale (JOA scale). METHODS: Clinicians from the same institute independently evaluated participating patients from their institute by two evaluations at a 1- to 4-week interval. Statistical evaluation was as follows. (1) The intraclass correlation coefficient (ICC) was calculated from data collected from at least two examinations of each patient by at least two evaluating clinicians (Data A). (2) Total scores for the two evaluations were determined from the distribution of differences in data between the two evaluations (Data B); each item was evaluated by determining Cohen's coefficient of agreement. (3) The relation between patient satisfaction and total score was investigated only for patients who underwent surgery (Data C). Spearman's rank correlation coefficient was obtained. RESULTS: Participants were 65 clinicians and 610 patients, including those with disorders of the AH (313), MF (47), HL (153), and LT (50) and those with RA (47). From Data A, the ICC was high for AH and HL by JSSF scales and for AH, MF, and LT by the JOA scale. From Data B, the coefficient showed high validity for both scales for AH, with almost no difference between the two scales; the validity for HL was higher with the JOA scale than with the JSSF scale. From Data C, correlations were significant between patient satisfaction and outcome for AH and HL by the JSSF scales and for AH, HL, and LT by the JOA scale. CONCLUSIONS: The validity of both scales was high. Clinical evaluation of the therapeutic results using these scales would be highly reliable.

Ankle↗

Emergency operation for phlegmonous gastritis.

Phlegmonous gastritis is a rare inflammatory lesion in which bacterial infection occurs in the gastric wall. A case of phlegmonous gastritis producing an intramural filling defect in the stomach is presented. Endoscopy showed edematous and reddened gastric mucosa with a mass lesion in the gastric body and antrum. An abdominal CT scan showed diffuse and irregular thickening of the gastric wall. At emergency operation, a total gastrectomy with splenectomy was performed. The most important differential diagnosis is carcinoma, especially scirrhous-type gastric cancer. Radiographic findings of phlegmonous gastritis resemble those of scirrhous gastric cancer. More frequent recognition of this disease, early diagnosis and prompt institution of treatment is essential.

Aged↗

Pyogenic liver abscesses secondary to carcinoma of the sigmoid colon: a case report and clinical features of 20 cases in Japan.

We report a case of liver abscesses associated with sigmoid colon cancer in an 81-year-old woman. The patient was referred to our hospital because of a tumorous lesion of the sigmoid colon. Five days before the scheduled operation, she presented abdominal pain, fever and chill. Imaging scans revealed multiple liver abscesses in both lobes, which were successfully treated with intravenously administered antibiotics. Two weeks later, the patient underwent laparoscopic-assisted sigmoidectomy. Nineteen cases of liver abscess associated with colonic cancer have been reported during the past ten years in Japan, and we report the clinical features of these cases in this paper. An aggressive search for the underlying cause of pyogenic liver abscess should be an integral part of the definitive treatment of this disease.

Aged, 80 and over↗

Angiomyolipoma in the knee--a case report.

Extrarenal angiomyolipoma is an uncommon disease and this may be the first report of angiomyolipoma in the knee, mimicking a malignant sarcoma. A 38-year-old man without tuberous sclerosis presented with a history of increased mass in the knee joint. Computerized tomography and magnetic resonance imaging demonstrated a CS x CS x CR cm subcutaneous tumor in the knee joint. The tumor was widely excised. Histologically, the tumor was, well circumscribed, and composed of smooth muscle, vascular spaces, connective tissue, and mature fat. There were no signs of recurrence at one year and eight months after surgery.

Adult↗

Desmoplastic melanoma arising in the ankle.

Desmoplastic melanoma (DM) is an uncommon but potentially devastating malignancy that can be cured with early recognition and surgery. DM often occurs in elderly men and develops on sun-exposed areas with the head and neck being the most common site of origin followed by the extremities and trunk. We report a rare case of DM occurring in the ankle in an 85-year-old woman. Magnetic resonance imaging of the affected ankle showed a 4.3 x 4.3 x 2.5 cm sized mass which was located in the subcutaneous region, attached to lower leg muscles, the fibula, and the calcaneus. No metastasis to the lung, liver, bones or abdominal lymph nodes was found. In spite of below knee amputation, the patient died of lung metastases 10 months after surgery. Among several factors causing early death of the patient, a large size, a deep location and rapid growth of the tumor seem to be most important.

Aged, 80 and over↗

Lipofibromatosis arising in a pediatric forearm--a case report.

Lipofibromatosis is a rare pediatric tumour described by Fetsch et al. in 2000. There have been few reports about this tumour and few descriptions of its imaging features. We report a case of this tumour forming a slowly growing, painless mass arising in the forearm of a ten-month-old boy. This is the first report of lipofibromatosis to present the radiological findings before surgery. Plain radiography and computed tomography demonstrated a tumour located just beneath the fascia. Ultrasonic study showed a hyperechoic tumour of 33 x 30 x 7 mm in size. Magnetic resonance imaging demonstrated a multilobular mass with high signal intensities on both T1/T2 weighted images. Macroscopically, the tumour was poorly marginated. Microscopically, the tumour was composed of abundant adipose tissues transversed by fibroblastic bands. The adipose tissue occupied over 70% of the tumour. Adipocytes and fibroblastic element infiltrated into the normal skeletal muscle tissues. Recognition of this clinical entity is needed, especially in cases of lipomatous tumours arising in pediatric hands and feet.

Fibroma↗

Skeletal muscle metastasis secondary to cancer--a report of seven cases.

Cancer metastasis to the skeletal muscle is very rare. In this report, we describe 7 cases (6 males, 1 female, age 55-76, mean 66 y.o.) with unusual presentation of cancer metastasis to the skeletal muscle, illustrating the principal clinical, radiographic and histologic features. The primary tumors were lung cancer in 4 cases (3 adenocarcinomas, 1 squamous cell carcinoma) and renal cell carcinoma, esophageal carcinoma, hepatocellular carcinoma in each one. The metastatic sites were the adductors, iliopsoas, rectus femoris, biceps bracii, triceps bracii, deltoid, and paravertebral muscle in each one. The unusual sites of metastases were visualized by CT and/or MRI and confirmed by needle or trocar biopsy. Five patients died in 2 to 24 months with the average of 8 months after initial examination.

Aged↗

Infantile fibrosarcoma of thigh--a case report.

Infantile fibrosarcoma is a rare soft tissue malignant tumor, when it occurs, it is usually seen in the first year of life. The clinical course of infantile fibrosarcoma is more favorable and metastasis is rare compared with that in adulthood. While adult fibrosarcoma are common in the thigh, infantile fibrosarcoma affect chiefly the distal portions of the extremities. Standard treatment is primarily wide surgical excision. In this case report, we present our experience of an infantile fibrosarcoma of thigh with good clinical course 36 months after tumor resection and the usefulness of detecting the ETV6-NTRK3 gene fusion in differential diagnosis.

DNA-Binding Proteins↗

Spindle cell lipoma showing biphasic pattern--a case report.

This is a case report of a rare spindle cell lipoma (SCL) showing an unusual biphasic pattern with radiological findings and histological features. SCL is most common in men between the ages of 45 and 65 and it is reported that the tumor has a tendency to occur in the posterior neck area. This case was a 75-year old man with a 7 x 5 cm subcutaneous tumor in the posterior neck. Magnetic resonance imaging (MRI) examination demonstrated an unusual biphasic pattern. The signal intensities on T1 and T2 weighted images of the outer layer of the mass were high, and were suppressed on fat suppression views and showed no enhancement after gadolinium (Gd) injection. There was a low signal intensity area of 15 mm in diameter on both T1 and T2 weighted images, in the central part of the mass. This area was well enhanced with the Gd compound. Also macroscopically it could be seen that the excised tumor consisted of two different tissue components. Microscopically, the outer yellowish portion was mainly composed of mature adipose tissue. The inner whitish fibrous portion contained a mixture of small and uniform spindle-shaped cells, collagen fibers, and scattered mature adipose cells. No malignancy was observed. The diagnosis of spindle cell lipoma was made. No recurrence was seen seven months after marginal excision.

Aged↗

Giant cell formation through fusion of cells derived from a human giant cell tumor of tendon sheath.

Although the mechanism of multinucleation in giant cell tumors of tendon sheath (GCTTS) remains unknown, two mechanisms have been proposed: one is cell fusion and the other amitotic division. The purpose of this study was to clarify the multinucleation process of cultured cells from GCTTS using an in vitro fluorescent cell membrane labeling technique. Cultured GCTTS cells obtained from a 7-year-old Japanese girl were divided into two groups, one for PKH-2 (green) staining and the other for PKH-26 (red) staining. After staining with the dyes, the cell populations were mixed and observed with a fluorescent microscope on the 4th and 14th days after mixing. On both the 4th and 14th days, the cultured GCTTS giant cells showed a mosaic of green and red colors, thus indicating cell membrane fusion. Images of double fluorescent labeled giant cells indicated cell fusion of mononucleated stromal cells that lead to multinucleated giant cells in these GCTTS cell cultures. These findings suggest that multinucleation in GCTTS results from the fusion of mononuclear stromal cells in vitro.

Animals↗

Post-laminectomy long-term survival of a patient with spinal cord compression secondary to metastatic prostate cancer.

Spinal cord compression is a skeletal-related event in advanced malignancies and is associated with serious morbidity and poor prognosis. Despite the palliative nature of laminectomy treatment, it is important to prevent neurological deficits and relieve pain as a means to improve quality of life. Here we report on a prostate cancer patient with spinal cord compression who became ambulant from paraparesis after he underwent a decompression laminectomy; he survived for 9.5 years with good quality of life.

Decompression, Surgical↗

Sex steroid receptors in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a disease characterized primarily by chronic inflammatory synovitis and is well-known to be associated with significant sex differences in its prevalence and clinical features. Sex steroids have been proposed to be involved in the pathogenesis of RA, but details pertaining to the expression of sex steroid receptors in RA synovial tissue have yet to be fully characterized. In the present study, we examined oestrogen receptor (ER) alpha, ERbeta, progesterone receptor (PR) and androgen receptor (AR) mRNA expression using real-time reverse transcriptase-PCR (RT-PCR) in eight female RA synovial tissues and six female synovial tissues without inflammation, and determined immunolocalization of ERalpha, ERbeta, PR-A, PR-B and AR using immunohistochemistry in synovial tissues obtained from 22 RA patients. Real-time RT-PCR analysis demonstrated the expression of ER, PR and AR mRNAs in both RA and non-inflamed synovial tissues. Relative abundance of ER mRNAs was significantly higher in RA synovial tissue than non-inflamed synovial tissue (P<0.05). In addition, the relative ERalpha/ERbeta mRNA expression ratio was significantly lower in RA than non-inflamed synovial tissue (RA, 2.34 +/- 1.60; and non-inflamed, 20.7 +/- 19.1; P<0.05). There were no significant differences in relative abundance of PR mRNA. Relative abundance of AR mRNA was significantly lower in RA (P<0.05). Immunoreactivity for ERalpha, ERbeta, PR-B and AR was detected in the lining cells, inflammatory cells and fibroblasts in all the patients examined. The labelling indices for ERbeta and PR-B were more abundant in both lining cells (ERbeta, 54.2 +/- 12.2%; PR-B, 73.6 +/- 18.9%) and inflammatory cells (ERbeta, 74.6 +/- 16.2%; PR-B, 75.9 +/- 16.1%) than in fibroblasts (ERbeta, 36.5 +/- 15.6%; PR-B, 49.4 +/- 18.0%). Labelling indices for ERalpha and AR were significantly higher in lining cells (ERalpha, 14.4 +/- 8.6%; AR, 31.2 +/- 11.3%) and fibroblasts (ERalpha, 12.1 +/- 7.5%; AR, 20.1 +/- 9.6%) than those in inflammatory cells (ERalpha, 5.7 +/- 3.3%; AR, 9.2 +/- 4.4%). There were significant differences (P<0.05) in the labelling indices for ERalpha, ERbeta and PR-B between men and women under 50 years of age in fibroblasts of RA synovial tissues. These results indicate that sex steroid receptors are present in RA and non-inflamed synovial tissues, including inflammatory cells in RA, and suggest that sex steroids may play important roles in the regulation of inflammation of RA synovial tissue.

Age Factors↗