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Biomedical subjects

M Kurosaka

Publications and source records attributed to M Kurosaka.

At least 55 records · Page 3Linked to original sources

Primary bone tumors of the femur presenting with spinal symptoms: a report of two cases and review of the literature.

Two case reports of femoral bone lesions simulating lumbar spinal disease are presented. Physical examination and case history were strongly suggestive of lumbar spinal pathology. In case 1, surgical resection of a venous hemangioma in the lumbar epidural space was performed but did not relieve pain. In case 2, conservative treatments for a protruded disk were performed for 3 months before an accurate diagnosis was made. After correct diagnoses were made, excision of the femoral tumors brought rapid relief of all abnormal findings in both cases. Compared with other causes of sciatica, femoral bone tumors are rare. However, careful attention should be paid to rule out these lesions if the diagnosis of a lumbar spinal disease is uncertain. Bone scintigraphy seems to be a sensitive diagnostic method to detect extraspinal osseous lesions.

Adult↗

Graft healing in the bone tunnel in anterior cruciate ligament reconstruction.

The histologic sequence in the bone tunnel after anterior cruciate ligament reconstruction using the bone-patellar tendon-bone graft was investigated in this study. Eighteen adult mongrel dogs were used. After excision of the anterior cruciate ligament, the graft was routed through the bone tunnels and fixed with interference fit screws. After the dogs were sacrificed at intervals, the bone blocks containing the bone tunnels were isolated and processed for histologic examination. At the bone-bone interface, incorporation of the bone plug at each end of the graft was completed at 12 weeks. The structure of the tendon insertion of the grafted patellar tendon, consisting of four distinct zones, was observed without apparent necrotic and degenerative change for as long as 12 weeks. Between the tendon and the bone tunnel, a layer of hypercellular fibrous tissue gradually became mature with time. Thus, it appeared the morphologic characteristics and location of the reestablished attachment of the bone-patellar tendon-bone graft were more similar to those of the native anterior cruciate ligament compared with the graft to bone healing in the hamstring tendon graft.

Animals↗

Radiographic and computed tomographic analysis of the position of the tibial tubercle in recurrent dislocation and subluxation of the patella.

Among the factors that influence the patellofemoral alignment and stability, the position of the tibial tubercle was evaluated using plain radiographs and computed tomography (CT). Radiographs of the Q-angle with the knee in full extension and quadriceps muscle relaxed showed that mean Q-angles in the dislocation or subluxation group and control group were 13.8 degrees and 14.3 degrees, respectively. The major reason for this deceptive measurement was a patella positioned laterally in the dislocation or subluxation group. Better estimation was made with the modified Q-angle measurement by using the most concave point of the intercondylar notch as a reference point instead of the center of the patella. By overshadowing CT images of the levels of the patellofemoral joint and the tibial tubercle, it was possible to evaluate the location of the tibial tubercle in relation to the femoral trochlea. Both the angular measurement (lateral deviation angle [LDA]) and the distance measurement (lateral deviation index [LDI]) showed that the tibial tubercle in the dislocation or subluxation group was rotated externally and shifted laterally (LDA, 36.3+/-7.0 degrees and LDI, 30.1+/-5.6) compared with the control group (LDA, 20.2+/-7.1 degrees and LDI, 15.1+/-5.6). Further study is warranted to elucidate the exact mechanism of recurrent patellar dislocation and subluxation.

Adult↗

Developmental and dynamic canal stenosis as radiologic factors affecting surgical results of anterior cervical fusion for myelopathy.

STUDY DESIGN: The correlation between preoperative and postoperative lateral functional radiograms and clinical results was analyzed in 74 cases of myelopathy treated by anterior cervical fusion. OBJECTIVES: To clarify the correlation between clinical results and radiologic findings (developmental and dynamic stenosis). SUMMARY OF BACKGROUND DATA: Although radiologic changes have been reported at the disc level adjacent to anterior cervical fusion, the question of whether these radiologic findings affect the clinical results of anterior fusion has not been resolved. METHODS: The "deteriorated" results group (28 cases) was composed of cases with deterioration of 2 points or more in the Japan Orthopedic Association score at follow-up compared with the postoperative best score. The "good" results group (46 cases) exhibited a recovery rate of > or = 50%. The two groups were compared in lateral functional roentgenograms on which the sagittal canal diameter in each vertebra and the diameter between the inferoposterior lip of the vertebral body and the anterior margin of the lamina of the distal vertebra in the extended neck were measured. A diameter of less than 12 mm was defined as developmental canal stenosis or dynamic canal stenosis. RESULTS: Fifty-four percent of the cases in the deteriorated results group had developmental canal stenosis, whereas the same findings were identified in only 2% of the cases in the good results group (P < 0.01). Preoperative dynamic canal stenosis at the disc level adjacent to the fusion was found in 64% of the patients in the deteriorated results group and in only 4% of the patients in the good results group (P < 0.01). CONCLUSIONS: Patients in the deteriorated results group showed a higher incidence of preoperative developmental and/or dynamic canal stenosis at the adjacent disc level than those in the the good results group. These results indicate that patients with preoperative developmental canal stenosis are not suitable candidates for anterior cervical fusion. When dynamic canal stenosis is found below or above the level of fusion, simultaneous fusion is recommended to avoid deterioration of the myelopathy.

Cervical Vertebrae↗

Efficacy of the axially loaded pivot shift test for the diagnosis of a meniscal tear.

Although magnetic resonance imaging (MRI) has improved the diagnostic accuracy of meniscal pathology, the authors believe that physical examination remains essential to the evaluation of knee pathology. In this study, the diagnostic accuracy of five clinical tests for meniscal pathology was prospectively evaluated in 160 patients, who thereafter underwent arthroscopy. 69% (109 knees) of the knees tested had associated ACL deficiency. There were 144 meniscal lesions in 130 of the 160 knees which were examined. The sensitivity of the tests was lower than the specificity. Conventional tests such as McMurray and Apley tests showed a low accuracy rate of 45% and 28% respectively. The diagnostic value of the axially loaded pivot shift test was significantly higher, indicating that this remains a useful diagnostic aid.

Adolescent↗

Evaluation of functional deficits determined by four different hop tests in patients with anterior cruciate ligament deficiency.

The purpose of this study was to analyze the validity of the newly designed functional ability test (FAT) for the normal population and patients with deficiency of the anterior cruciate ligament (ACL). The FAT consists of four tests: the figure-of-eight hop, the up-down hop, the side hop, and the single hop. Sixty control subjects and 50 patients with unilateral ACL deficiency were tested. In the control group, the values measured were significantly different between males and females in all of the tests. On the other hand, when left/right difference values were compared, no significant difference was found between males and females in any of the tests. More than 95% of control group exhibited symmetrical function in each part of the FAT, whereas in the ACL-deficient group, the percentage of patients who showed abnormal symmetry was 68% in the figure-of-eight hop, 58% in the up-down hop, 44% in the side hop, and 42% in the single hop. The percentage of ACL-deficient patients with functional asymmetry in at least one of the four tests was 82%. The FAT was found to be useful in evaluating lower limb function in ACL-deficient patients.

Adolescent↗

Extension injury of the thoracolumbar spine.

STUDY DESIGN: This is a report of a patient with a rare fracture in the thoracolumbar spine. OBJECTIVES: To illustrate the previously undescribed fracture in the thoracolumbar spine and to propose a new mechanism of this rare lesion with a literature review. SUMMARY OF BACKGROUND DATA: Extension injury of the thoracolumbar spine is uncommon. Although there have been several reports of hyperextension injuries in the thoracolumbar spine, the injury mechanism of the present case was different from those in the previously reported cases. METHODS: The clinical findings, roentgenographic appearance, treatment, and follow-up result were presented, and the mechanism of this lesion was analyzed. RESULTS: Physical examination revealed no neurologic deficit. Radiographs showed the oblique fracture line extended from the middle region of the L1-L2 disc to the posteroinferior edge of the L2 vertebral body, with the widening of bilateral L2-L3 facet joints. The patient was treated conservatively with a successful outcome. Two years after his injury, the patient had resumed his previous activity completely. CONCLUSIONS: The authors considered that the mechanism of this rare injury was a combination of hyperextension force and axial loading.

Adult↗

Effect of basic fibroblast growth factor on the healing of defects in the canine anterior cruciate ligament.

The effect of basic fibroblast growth factor (bFGF) on the healing of partial anterior cruciate ligament (ACL) lacerations was investigated in 17 adult mongrel canines. The defect was created in the midsubstance of both ACLs using a biopsy punch. In the bFGF group, a bFGF-impregnated pellet was sutured to the infrapatellar fat pad close to the defect. In the control group, the same pellet without bFGF was used. The healing process was evaluated macroscopically and histologically at 1, 3, 6, and 24 weeks postoperatively. In the bFGF group, a pannus-like tissue which contained abundant blood vessels extended into the defect from the adjacent synovial tissue in the early postoperative phase. Histological examination of the tissue which filled the defect revealed initial remodeling processes with a decreased number of cells and better orientation of the collagen fibers at 6-24 weeks. On the other hand, in the control group, poor healing processes were observed at each examination period. This study demonstrated that the application of a bFGF-impregnated pellet may enhance the healing potential of a partially injured ACL. Enhanced neovascularization and the formation of granulation tissue induced by bFGF early in the healing process accounted for the increased healing response.

Animals↗

Athletic knee injuries. Similarities and differences between Asian and Western experience.

The pattern and prevalence of knee injuries among athletes are different in Asia, Europe, and North America because of factors such as the different sporting cultures of the regions and the type of favorite sports. Sampling and data bias and the variable levels of diffusion of sports in the different parts of the world also are responsible for the variation. In this review, the knee emerges as the most commonly injured part of the body; such injuries present significant problems of mechanical block or instability that may compromise athletic performance. Sports specific injuries are delineated, and specific groups, such as children and adolescents, female, and master athletes, are reviewed in light of the characteristic patterns of knee injuries. Differences in the patients' attitude, health care systems, and consultations of traditional medical practitioners produce major differences in management styles. However, it is encouraging to find a concerted effort on all continents in the search for a better understanding of knee injuries and a more satisfactory coordination between clinical and basic science research in this field.

Adolescent↗

Effect of fibrin glue and endothelial cell growth factor on the early healing response of the transplanted allogenic meniscus: a pilot study.

Twentyfour meniscal allotransplantations were conducted in 12 adult mongrel dogs. The medial meniscus was replaced using a deep-frozen meniscal allograft. The junction between the meniscus and capsule was treated in one of the three ways. In the control group, the meniscus was sutured only to the adjacent capsular tissue (group C). In the second group, fibrin glue was injected at the junction (group F), and in the third group, fibrin glue and endothelial cell growth factor (ECGF) were injected at the juncture between the transplanted meniscus and the adjacent capsule before the meniscus was sutured (group FE). Histological observation was performed to investigate the effect of fibrin glue and ECGF on the healing process of transplants at various intervals of 1, 4, 8 and 12 weeks. No immunological response was noted in any of the knees. The healing of the transplanted meniscus was first observed at the peripheral attachment. Also, the pannus-like tissue extended from the synovium to the surface of the meniscus. The healing rate in each group at 1 week and 12 weeks was 22% and 77% in group C, 52% and 80% in group F, and 64% and 80% in group FE, respectively. At 4 and 8 weeks, early cellular repopulation was found in group FE and the area which contained new cells was larger than the acellular central core at 8 weeks. However, there was no difference among the three groups at 12 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Analysis of the drill hole orientation in anterior cruciate ligament reconstruction].

In the reconstructive procedure of the anterior cruciate ligament (ACL), the relationship was investigated between the orientation of the drill holes from the isometric points and the deformity in the ligament graft. We first investigated, by numerical analysis, the optimal orientation of the drill holes for minimal deformation. Secondly, we experimentally by using eight fresh cadaveric knees, measured the relationship between the orientation of the drill holes and the bending angle in the grafts. The optimal orientation of the drill hole in the femur was found to be tilted 20 degrees laterally in the coronal plane and 23 degrees anteriorly in the sagittal plane. In the tibia, the drill hole should be directed 24 degrees medially and 50 degrees anteriorly from the isometric point. The numerically analysed bending angle corresponded well to the results from the experimental study. The deformation in the graft on the femoral side was larger than that on the tibial side. Therefore, the orientation of the femoral drill hole was concluded to be more important than the orientation of the tibial drill hole.

Anterior Cruciate Ligament↗

Light and electron microscopic study of remodeling and maturation process in autogenous graft for anterior cruciate ligament reconstruction.

We evaluated the remodeling process of autogenous patellar tendon graft for anterior cruciate ligament (ACL) reconstruction by means of light microscopic (LM) and electron microscopic (EM) examinations from the biopsy specimens obtained at the time of second-look arthroscopy. Twenty-one patients were examined at various times postoperatively (from 6 weeks to 15 months, mean 9.5 months), and the results were correlated with the morphology of normal patellar tendon and normal ACL. Our study showed that the graft was revascularized in the early postoperative period, fibroblastic remodeling took place, and the graft obtained gross similarity to the original ACL on their arthroscopic and LM appearances at approximately 1 year postoperatively. However, EM study showed that at both approximately 6 months and 1 year postoperatively the grafts consisted equally of active fibroblasts with a higher cytoplasm-to-nucleus ratio compared with normal ACL. Collagen fibrils of these grafts were of uniformly small diameter compared with normal patellar tendon and ACL. Our results with ultrastructural study suggest that the grafts were still immature even at 1 year postoperatively.

Adolescent↗

[Clinical usefulness of the measurement of type-II procollagen carboxypeptide (C-II propeptide, pColl-II-C) in synovial fluid as a marker of collagen metabolism in cartilage].

Type-II procollagen-C-peptide (pColl-II-C) in synovial fluids was studied in 319 patients with osteoarthritis (OA; 151), rheumatoid arthritis (RA; 141), traumatic arthritis (TA; 27) and 15 healthy volunteers using the newly developed ELISA kit. The mean levels of pColl-II-C in synovial fluids of healthy controls, OA, TA, and RA were 0.3 +/- 0.1 ng/ml, 5.9 +/- 0.3 ng/ml, 6.8 +/- 1.4 ng/ml and 1.1 +/- 0.1 ng/ml, respectively. pColl-II-C levels in synovial fluids of OA and TA were significantly higher compared to those of healthy controls and RA. It was also demonstrated that pColl-II-C levels could reflect the quantitative and qualitative change of cartilage metabolism. Therefore, the quantification of this molecule in synovial fluid could be beneficial to know the synthetic activity of type II collagen of chondrocytes, since pColl-II-C is a part of the precursor molecule of type II collagen.

Adolescent↗

Weakness of thigh muscles in individuals sustaining anterior cruciate ligament injury.

The purpose of this study was to assess the quadriceps and hamstrings muscle strength deficits at different knee flexion angles (30 degrees and 60 degrees) in individuals who had sustained anterior cruciate ligament (ACL) injury, who had never had thigh muscle strengthening exercise. Isometric (0 degree/sec) and isokinetic (60 degrees/sec and 180 degrees/sec) torque measurements were performed on sixty-six patients (29 males and 37 females) with chronic ACL insufficiency. Significant strength deficits of the quadriceps and hamstrings muscles in injured knees were found at both 30 degrees and 60 degrees of knee flexion in three testing conditions (0 degree/sec, 60 degrees/sec, and 180 degrees/sec). In the comparison of torque production at 30 degrees and 60 degrees knee flexion angles, for the male group, significantly greater deficits of the quadriceps torque were found at 60 degrees knee flexion than at 30 degrees knee flexion in the isometric and isokinetic 60 degrees/sec testing modes. For the female group, significantly greater deficit of the quadriceps torque was found at 60 degrees knee flexion than at 30 degrees knee flexion only in isokinetic 60 degrees/sec. There was no significant difference of the hamstrings torque deficit between 30 degrees and 60 degrees knee flexion in any testing modes. In the comparison of isometric and two isokinetic testing modes (60 degrees/sec and 180 degrees/sec), for the male group, significantly greater deficits of the quadriceps torque were found at 30 degrees knee flexion in isokinetic 180 degrees/sec and at 60 degrees knee flexion in isokinetic 60 degrees/sec as compared to the isometric test. There was no statistical difference in the hamstrings torque values. For the female group, significantly greater deficits of the quadriceps and hamstrings torque were found at 30 degrees knee flexion in isokinetic 60 degrees/sec and at 60 degrees in isokinetic 60 degrees/sec and 180 degrees/sec as compared to the isometric test. It was concluded that long lasting instability without any muscle exercises may result in the weakness of not only the quadriceps muscle but also even hamstrings muscle, and that the quadriceps strength might be more susceptible to ACL insufficiency at 60 degrees knee flexion angle than at 30 degrees knee flexion angle, whereas, the hamstrings did not show any angular-specific torque deficits. These findings might resulted from characteristics of torque-curves of the quadriceps and hamstrings muscles.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

Arthroscopic evaluation of synovitis in the knee joints.

It is not always easy to diagnose certain types of monoarthritis of the knee joints. In such cases, it is essential to evaluate the condition of the synovitis both macroscopically and microscopically, as the synovial appearance (synovitis) closely reflects the pathological condition (arthritis) of the knee joints. Arthroscopy is an excellent tool for visualizing and evaluating the condition of the synovium macroscopically. On arthroscopic examination, precise evaluation of the villi often provides clues, enabling accurate diagnosis. In addition, histological sections obtained from biopsy specimens in various cases of synovitis give significant information. In this article, arthroscopic observation and histological sections of various cases of synovitis are compared, and the diagnostic value and limitations of arthroscopic examination are discussed.

Arthritis↗