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Dive into the research topics where Yoshinori Takakura is active.

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Featured researches published by Yoshinori Takakura.


Journal of Bone and Joint Surgery, American Volume | 1999

Arthroscopic drilling for the treatment of osteochondral lesions of the talus

Tsukasa Kumai; Yoshinori Takakura; Ichiro Higashiyama; Susumu Tamai

BACKGROUND An osteochondral lesion of the talus is a relatively rare disorder of the ankle. While a number of treatment options have been reported, it appears to be difficult to manage all lesions with a single approach. We evaluated the indications for and the results of arthroscopic drilling for the treatment of an osteochondral lesion of the talus. METHODS Eighteen ankles (seventeen patients) with a symptomatic osteochondral lesion of the talus were examined. The ages of the patients ranged from ten to seventy-eight years (mean, 28.0 years) at the time of the operation, and the patients were followed postoperatively for two to 9.5 years (mean, 4.6 years). After the continuity of the cartilage overlying the lesion and the stability of the lesion had been confirmed, arthroscopic drilling was performed with use of a Kirschner wire that was 1.0 to 1.2 millimeters in diameter. A cast was not applied postoperatively, and full weight-bearing was allowed six weeks after the procedure. RESULTS The clinical result was good for thirteen ankles and fair for five; all ankles had improvement. Twelve of the thirteen ankles that were in patients who were less than thirty years old had a good result. In contrast, only one of the five ankles in patients who were fifty years old or more had a good result. Thus, the clinical results tended to be better for younger patients. Improvement was seen radiographically in fifteen ankles. However, the three ankles in patients who were more than sixty years old were found to have no improvement on radiographic examination. Analysis of the group of patients who had a history of trauma revealed that the mean interval between the injury and the operation was 6.3 months for the three ankles that had a good radiographic result and 11.3 months for the six that had a fair result. Thus, the radiographic results tended to be better when the interval between the injury and the operation was shorter. CONCLUSIONS Arthroscopic drilling for the treatment of medial osteochondral lesions of the talus does not require osteotomy of the medial malleolus or postoperative immobilization; thus, the procedure is less invasive than other types of operative treatment for the condition and it allows early resumption of daily activities and sports. On the basis of the results in this study, we believe that the procedure is effective and useful in young patients, especially those who have not yet had closure of the epiphyseal plate. A specific indication for the procedure is an early lesion with only mild osteosclerosis of the surrounding talar bone, continuity of the cartilaginous surface, and stability of the osteochondral fragment.


Journal of Bone and Joint Surgery-british Volume | 1995

Low tibial osteotomy for osteoarthritis of the ankle. Results of a new operation in 18 patients

Yoshinori Takakura; Yasuhito Tanaka; Tsukasa Kumai; Susumu Tamai

Primary osteoarthritis of the ankle with no history of trauma is rare. We report the use of a low tibial osteotomy on 18 ankles in 18 patients, two men and 16 women. The osteotomy is designed to correct the varus tilt and anterior opening of the distal tibial joint surface where it has been shown by weight-bearing radiographs and arthroscopy that there is healthy articular cartilage on the lateral side of the ankle. An opening-wedge osteotomy was used to achieve slight overcorrection. Follow-up of the 18 ankles at an average of 6 years 11 months (2.7 to 12.10) showed the results by our own scoring system to be excellent in six ankles, good in nine, and fair in three with no poor results. Of the three patients with fair results, two had been undercorrected and the third had little residual articular cartilage. Arthroscopic examination of ten ankles showed repair by fibrocartilage in seven. We conclude that slight overcorrection of deformity by low tibial osteotomy is effective in treating intermediate-stage primary osteoarthritis of the ankle.


Spine | 2010

Disc regeneration therapy using marrow mesenchymal cell transplantation: a report of two case studies.

Takafumi Yoshikawa; Yurito Ueda; Kiyoshi Miyazaki; Munehisa Koizumi; Yoshinori Takakura

Study Design. Marrow mesenchymal cells (MSCs) contain stem cells and possess the ability to regenerate bone, cartilage, and fibrous tissues. Here, we applied this regenerative ability to intervertebral disc regeneration therapy in an attempt to develop a new spinal surgery technique. Objective. We analyzed the regenerative restoration ability of autologous MSCs in the markedly degenerated intervertebral discs. Summary of Background Data. Fusion for lumbar intervertebral disc instability improves lumbago. However, fused intervertebral discs lack the natural and physiologic functions of intervertebral discs. If intervertebral discs can be regenerated and repaired, then damage to adjacent intervertebral discs can be avoided. We verified the regenerative ability of MSCs by animal studies, and for the first time, performed therapeutic intervertebral disc regeneration therapy in patients and obtained favorable findings. Methods. Subjects were 2 women aged 70 and 67 years; both patients had lumbago, leg pain, and numbness. Myelography and magnetic resonance imaging showed lumbar spinal canal stenosis, and radiograph confirmed the vacuum phenomenon with instability. From the ilium of each patient, marrow fluid was collected, and MSCs were cultured using the medium containing autogenous serum. In surgery, fenestration was performed on the stenosed spinal canal and then pieces of collagen sponge containing autologous MSCs were grafted percutaneously to degenerated intervertebral discs. Results. At 2 years after surgery, radiograph and computed tomography showed improvements in the vacuum phenomenon in both patients. On T2-weighted magnetic resonance imaging, signal intensity of intervertebral discs with cell grafts was high, thus indicating high moisture contents. Roentgenkymography showed that lumbar disc instability improved. Symptom was alleviated in both patients. Conclusion. The intervertebral disc regeneration therapy using MSC brought about favorable results in these 2 cases. It seems to be a promising minimally invasive treatment.


Clinical Orthopaedics and Related Research | 1999

Long-term results of arthrodesis for osteoarthritis of the ankle.

Yoshinori Takakura; Yasuhito Tanaka; Kazuya Sugimoto; Koichi Akiyama; Susumu Tamai

A bone graft in the shape of a triangular prism was taken from the anterior surface of the tibia and used in the arthrodesis in 43 joints of 42 patients with primary and secondary osteoarthritis of the ankle. The modified anterior sliding inlay graft method was used. The average period of external immobilization was 5.8 weeks (range, 27-84 days), and followup ranged from 2 years 4 months to 14 years 11 months (average, 7 years 2 months). Nonunion was detected in three (7%) patients: one patient returned to work without additional treatment, and the other two patients underwent followup surgery within 7 months, and bony union was achieved. The final rate of nonunion was 2.3%. After the operation, excellent alleviation of pain was obtained. However, dorsiflexion of the foot decreased from the preoperative average value of 10.5 degrees to the postoperative value of 4.2 degrees, and plantar flexion also decreased from the preoperative value of 24.7 degrees to the postoperative value of 14 degrees. In addition, the range of motion of the subtalar and Chopart joints gradually improved with little effect on daily living activities. The most appropriate position of arthrodesis of the ankle appears to be in the neutral position between dorsal and plantar flexion. In addition, the varus and valgus angle of the hindfoot should be in a neutral or slightly valgus position. Degenerative arthritis developed and advanced in the subtalar joint in 32.5% of the patients, and these degenerative changes were exacerbated in many patients if such changes were present before surgery. Tibial stress fracture occurred in two (4.7%) patients as a complication that was specific to the current surgical method. Thus, the surgical procedure was modified to prevent the onset of tibial stress fracture.


Journal of Bone and Joint Surgery-british Volume | 2006

Low tibial osteotomy for varus-type osteoarthritis of the ankle

Yasuhito Tanaka; Yoshinori Takakura; Koji Hayashi; Akira Taniguchi; Tsukasa Kumai; Kazuya Sugimoto

In this retrospective study we have assessed the results of low tibial valgus osteotomy for varus-type osteoarthritis of the ankle and its indications. We performed an opening wedge osteotomy in 25 women (26 ankles). The mean follow-up was for eight years and three months (2 years 3 months to 17 years 11 months). Of the 26 ankles, 19 showed excellent or good clinical results. Their mean scores for pain, walking, and activities of daily living were significantly improved but there was no change in the range of movement. In the ankles which were classified radiologically as stage 2 according to our own grading system, with narrowing of the medial joint space, and in 11 as stage 3a, with obliteration of the joint space at the medial malleolus only, the joint space recovered. In contrast, such recovery was seen in only two of 12 ankles classified as stage 3b, with obliteration of the joint space advancing to the upper surface of the dome of the talus. Low tibial osteotomy is indicated for varus-type osteoarthritis of stage 2 or stage 3a.


Journal of Bone and Joint Surgery, American Volume | 1998

Results of Opening-Wedge Osteotomy for the Treatment of a Post-Traumatic Varus Deformity of the Ankle*

Yoshinori Takakura; Takanori Takaoka; Yasuhito Tanaka; Hiroshi Yajima; Susumu Tamai

&NA; We performed a one-stage opening-wedge valgus osteotomy in nine patients to correct a post-traumatic progressive varus deformity of the ankle. The osteotomy site was stabilized with two, three, or four Kirschner wires or with a plate and screws (in one patient). The site of the osteotomy united within two months after the operation in eight patients and at six months in one patient who was fifty-nine years old. The average duration of follow-up was seven years and four months (range, two years and four months to thirteen years and two months). Postoperatively, the range of motion of the ankle was decreased in six patients and remained unchanged in three. However, none of the patients reported any limitation in the activities of daily living, and the four adolescent patients were able to participate in sports activities. The result was graded as excellent for four ankles, good for two, and fair for three.


Clinical Orthopaedics and Related Research | 1990

Ankle arthroplasty : a comparative study of cemented metal and uncemented ceramic prostheses

Yoshinori Takakura; Yasuhito Tanaka; Kazuya Sugimoto; Susumu Tamai; Kenji Masuhara

From 1975 to 1980, total ankle arthroplasty was performed using a metal and polyethylene prosthesis on 30 ankles in 28 patients with painful arthritis. However, because loosening and sinking of the prosthesis were significant, a ceramic total prosthesis was designed in 1980 to be used without cement. Between 1980 and 1987, 39 ankles in 35 patients with osteoarthritis, rheumatoid arthritis, and hemophilic arthritis were replaced using the ceramic prosthesis. Out of 39 ankles, nine were replaced with cement and 30 without cement. The follow-up period for the cemented metal and ceramic cases ranged from 13.4 to 6.2 years, with an average of 8.1 years, and for uncemented ceramic cases from 1.2 to 6.4 years, with an average of 4.1 years. Based on a rating scale for ankle evaluation, 27% of the cemented cases and 67% of the uncemented cases are satisfactory. Five metal ankles and one ceramic ankle were reoperated upon, with one revision and five arthrodeses performed. Ceramic total ankle arthroplasty, performed without cement, has to date provided mostly excellent stable results.


Tissue Engineering Part C-methods | 2009

Osteocalcin secretion as an early marker of in vitro osteogenic differentiation of rat mesenchymal stem cells.

Akifumi Nakamura; Yoshiko Dohi; Manabu Akahane; Hajime Ohgushi; Hiroshi Nakajima; Hiroyuki Funaoka; Yoshinori Takakura

Osteocalcin (OC) is a bone-specific protein synthesized by osteoblasts that represents a good marker for osteogenic maturation. We examined whether in vitro osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (MSCs) could be simply assessed at earlier stages by monitoring OC secretion into the conditioned medium, rather than measuring OC deposition on the extracellular matrix (ECM), using a sandwich enzyme immunoassay system involving a specific anti-rat OC monoclonal antibody. During a 16-day culture, OC was secreted into the medium of MSCs from day 8 and increased substantially until day 16. In contrast, OC deposition on the ECM was low, even at day 13, when calcium deposition was at high levels. The histological expression pattern of OC messenger RNA provided in situ evidence that osteoblastic cells appeared at the early stages of 6 to 9 days and matured over time in vitro. Furthermore, the temporal expression of osteogenesis-specific genes, such as the transcriptional factors core-binding factor 1 and osterix, followed by increases in secretory OC proved the commitment of MSCs to osteoblastic differentiation. These results revealed that biomineralization followed secretion of OC, which may reflect early osteoblastic differentiation of cultured MSCs under osteoinductive conditions. We ascertained the osteogenic differentiation capacity of cultured MSCs in a non-destructive manner by monitoring OC secretion into the culture medium and proved that secretory OC could represent a reliable marker for predicting in vivo osteogenic potential in bone tissue engineering.


Journal of Bone and Joint Surgery-british Volume | 1991

Tarsal tunnel syndrome. Causes and results of operative treatment

Yoshinori Takakura; Chikara Kitada; Kazuya Sugimoto; Yasuhito Tanaka; Susumu Tamai

From 1975 to 1988, operative treatment was performed on 50 feet in 45 patients with tarsal tunnel syndrome. The causes of this syndrome were correlated with operative findings and included ganglia in 18, and a bony prominence from talocalcaneal coalition in 15. Five feet had sustained an injury, tumours were found in three and there was no obvious cause in nine. In most cases in need of operative treatment, there was a space-occupying lesion. Classifying the results according to causes, those with coalition or a tumour fared better, and idiopathic and traumatic cases had a worse outcome. In cases with a definite lesion, an excellent result can be expected from surgical treatment carried out soon after onset of the condition.


Journal of Bone and Joint Surgery, American Volume | 2003

Anatomy of the spring ligament.

Akira Taniguchi; Yasuhito Tanaka; Yoshinori Takakura; Kunihiko Kadono; Manabu Maeda; Hiroshi Yamamoto

BACKGROUND The spring ligament has been reported to be composed of the inferior calcaneonavicular and superomedial calcaneonavicular ligaments. We investigated the lower layer of the spring ligament fibrocartilage complex under the fibrocartilaginous surface, identified three distinct structures, and examined the morphology and running patterns of their fiber bundles. METHODS Forty-eight cadaveric feet were examined. After ablation of the ankle joint and extirpation of the talus, the surface cartilage of the spring ligament fibrocartilage complex was carefully removed with forceps, and the length, width, and thickness of the three components of the complex were measured with calipers. RESULTS The three components of the spring ligament complex are the superomedial calcaneonavicular ligament, the inferior calcaneonavicular ligament, and a structure that we termed the third ligament, which comprises fibers running from the notch between the calcaneal facets to the navicular tuberosity. CONCLUSIONS We demonstrated a third component of the spring ligament; this component runs from the notch between the anterior and middle calcaneal facets to the tubercle of the navicular in the lower layer of the spring ligament complex, lying beneath the cartilaginous surface of the complex.

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Kazuya Sugimoto

National Archives and Records Administration

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Hajime Ohgushi

National Institute of Advanced Industrial Science and Technology

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Susumu Tamai

Nara Medical University

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Tsukasa Kumai

National Archives and Records Administration

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Koji Hattori

Nara Medical University

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