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Dive into the research topics where Hiroya Sakai is active.

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Featured researches published by Hiroya Sakai.


Journal of Spinal Disorders & Techniques | 2006

Traumatic anterior lumbosacral dislocation caused by hyperextension mechanism in preexisting L5 spondylolysis: a case report and a review of literature.

Kunio Saiki; Shigeru Hirabayashi; Hiroya Sakai; Kouichi Inokuchi

Of many reports referring to injury mechanism in anterior lumbosacral dislocation, there were none concerning hyperextension mechanism. We report a case of a 46-year-old man with preexisting L5 spondylolysis sustaining traumatic complete anterior lumbosacral dislocation. The operative findings, together with the radiologic findings, strongly suggested that the dislocation occurred by hyperextension mechanism. Open reduction was done by applying force of distraction with flexion using a rod and screw system, followed by the internal fixation from the L3 to S1 vertebrae and the postero-superior iliac spine. The lumbosacral dislocation was reduced to 77%. At the follow-up at 5 years after surgery, bony union was obtained and the patient could move with a wheelchair although the neurologic deficit in lower extremities observed preoperatively did not recover. Preexisting L5 spondylolysis was considered to increase the potential for anterior lumbosacral dislocation by additional force of compression with hyperextension. Posterior instrumentation using a rod and screw system was considered a useful method for reduction, decompression, stabilization, and fusion.


Clinical Orthopaedics and Related Research | 2002

Iliac Bone Graft for Steroid-associated Osteonecrosis of the Femoral Condyle

Naoshi Fukui; Hisashi Kurosawa; Akira Kawakami; Hiroya Sakai; Kozo Nakamura

The use of steroid medication may predispose to osteonecrosis of the femoral condyle. However, there is a controversy regarding treatment of this disease, especially for lesions in advanced stages. Since 1987, the authors have treated such lesions by autologous osteoperiosteal graft obtained from the iliac bone. When limb alignment was affected by the disease, proximal tibial valgus or varus osteotomy was done concomitantly. The rationale for this method is to replace the necrotic bone and damaged cartilage by autogenous bone and periosteum, anticipating the chondrogenic potential of the latter. In this study, 10 knees in eight patients were reviewed to learn the outcome of this procedure with a mean followup of 79 months (range, 32–158 months). The grafts were incorporated successfully in nine joints, and satisfactory results were achieved in all patients. Therefore autologous iliac bone graft is a promising alternative for treatment of osteonecrosis, especially when patients are young and physically active.


Journal of Hand Surgery (European Volume) | 2014

Simultaneous modified Camitz opponensplasty using a pulley at the radial side of the flexor retinaculum in severe carpal tunnel syndrome

Naoki Kato; Takahiro Yoshizawa; Hiroya Sakai

Camitz opponensplasty using the palmaris longus has been used in patients undergoing open carpal tunnel release. It is considered to have several advantages over other opponensplasty techniques, but it provides weak flexion and pronation, which are prerequisites for opposition. To address this shortcoming, we have used a modified Camitz procedure with a pulley at the radial side of the dissected flexor retinaculum and have assessed the results in comparison with the conventional Camitz procedure. Both procedures provided significant improvements in palmar abduction and Disabilities of the Arm, Shoulder, and Hand and Kapandji scores at 3 months post-operatively, but patients who underwent the modified Camitz procedure showed better improvement in pulp pinch, palmar abduction, and thumb pronation.


Foot & Ankle International | 2001

Anterior dislocation of the subtalar joint: a case report.

Toyohiko Kanda; Hiroya Sakai; Kunihiko Koseki; Kazuya Tamai; Noriyuki Takeyama; Koichi Saotome

We report a very rare case of anterior dislocation of the subtalar joint. Forceful supination of the foot and dorsiflexion of the ankle was considered the cause of the injury in this case. Closed reduction was successful for the talocalcaneal component of subtalar joint, although surgery was subsequently performed because of the residual subluxation of the midtarsal joint including the talonavicular component of subtalar joint and the associated fracture of the lateral process of the talus. Satisfactory results were shown at three-year follow-up.


Clinical Orthopaedics and Related Research | 2004

Effect of hyperbaric oxygen on the ligament healing process in rats.

Hirotaka Mashitori; Hiroya Sakai; Noriyuki Koibuchi; Hideki Ohtake; Toshiyuki Tashiro; Kazuya Tamai; Koichi Saotome

Animal experiments were done to investigate whether administration of hyperbaric oxygen promotes scar tissue formation, increases expression of the Type I procollagen gene, and improves the tensile properties of healing ligament. In 76 Sprague-Dawley rats, a 2-mm segment of the medial collateral ligament was removed. Thirty-eight rats were exposed to hyperbaric oxygen at 2.5 atmospheres absolute for 2 hours 5 days per week (Group H), whereas the remaining rats were exposed to room air (Group C). The animals were sacrificed at 3, 7, 14, and 28 days postoperatively. In situ hybridization histochemistry was done to examine the Type I procollagen gene expression in healing ligaments in 40 rats, whereas a tensile failure test was done in the remaining rats. The amount of scar tissue was greater in Group H than in Group C. Type I procollagen gene expression at 7 or 14 days was significantly greater in Group H than in Group C. The ultimate load and stiffness in Group H were significantly greater than in Group C at 14 days. Administration of hyperbaric oxygen promotes scar tissue formation and increases Type I procollagen gene expression in healing ligaments. These effects are associated with the improvement of their tensile properties.


Journal of Clinical Neuroscience | 2009

Occipitocervical fusion using a hook and rod system between cervical levels C2 and C3

Takao Motosuneya; Shigeru Hirabayashi; Hironobu Yamada; Hiroya Sakai

We aimed to evaluate the clinical utility and safety of the hook and rod method for occipitocervical fusion. Eleven consecutive patients (3 males, 8 females; 50-78 years old, average 63.8 years; 16-77 months follow-up, average 33.7 months) with unstable lesions at the craniocervical junction who underwent occipitocervical fusion using a hook and rod system were examined. A Compact Cotrel-Dubousset cervical system (Sofamor-Danek, Memphis TN, USA) was used in all patients. The claw mechanism was applied bilaterally between the hook on the C2 lamina and the hook on the C3 inferior articular process. No complications occurred during surgery. Solid bony fusion was obtained in all patients and no patient became clinically worse postoperatively. Occipitocervical fusion using a hook and rod system is a useful procedure that allows decompression of the spinal cord and secure spinal fusion at multiple levels simultaneously.


Case reports in orthopedics | 2016

Spontaneous Recurrent Hemarthrosis of the Knee: A Report of Two Cases with a Source of Bleeding Detected during Arthroscopic Surgery of the Knee Joint

Eisuke Nomura; Hisatada Hiraoka; Hiroya Sakai

We report two cases of the spontaneous recurrent hemarthrosis of the knee. In these cases lateral meniscus was severely torn and a small tubular soft tissue with pulsation was identified on the synovium in the posterolateral corner during arthroscopic surgery of the knee joint. Gentle grasping of this tissue by forceps led to pulsating bleeding, which stopped by electrocoagulation. This soft tissue was considered a source of bleeding, since no recurrence of hemarthrosis was observed for more than four years after surgery. It was highly probable that this soft tissue was the ruptured end of the lateral inferior genicular artery or its branch. This case report strongly supports the theory that the bleeding from the peripheral arteries of the posterior portion of the lateral meniscus is the cause of spontaneous recurrent hemarthrosis of the knee.


Journal of Orthopaedic Science | 2014

Useful MRI assessment for bowstringing of the flexor tendon after trigger finger release

Naoki Kato; Takahiro Yoshizawa; Hiroya Sakai

Bowstringing of the flexor tendon because of inadvertent disruption of the A2 pulley has been routinely described as a complication after the release of trigger fingers. In this report, we present two cases of bowstringing of the flexor tendon after release of trigger fingers. In both cases, magnetic resonance imaging (MRI) with the finger in flexion was useful for definitive diagnosis, and reconstruction of the A2 pulley by the double loop technique using the palmaris longus (PL) tendon resulted in satisfactory outcome.


European Spine Journal | 2008

Posterior atlantoaxial subluxation due to os odontoideum combined with cervical spondylotic myelopathy : a case report

Takao Motosuneya; Shigeru Hirabayashi; Hironobu Yamada; Yousuke Kobayashi; Shigeki Sekiya; Hiroya Sakai

In patients with os odontoideum and posterior atlantoaxial subluxation are extremely rare. No reports have described posterior atlantoaxial subluxation associated with os odontoideum combined with cervical spondylotic canal stenosis, both of which require surgical treatment. We report one case of a 75-year-old female who underwent arthrodesis between the occiput and C3 using a hook-and-rod system and also a double-door laminoplasty from levels C3 to C7. The claw mechanism was applied between the C2 lamina and the C3 inferior articular process. The posterior atlantoaxial subluxation was completely reduced by the method that the rod gradually pushed the posterior arch of C1 anteriorly during connection to the occiput. Twelve months after surgery, the patient showed improvement in preoperative clumsiness and gait disturbance, and the latest plain radiographs showed solid osseous fusion, with no loss of correction or instrumentation failure.


Journal of trauma and treatment | 2012

Radiohumeral Arthrodesis for Severe Open Communited Fracture Using External Fixation: A Case Report

Naoki Kato; Tetsuya Torio; Hiromi Oda; Hiroya Sakai

Recently, prosthetic replacement has been commonly applied as a standard procedure for the elbow joint destruction by arthritis or trauma, and elbow arthrodesis has been used only for patients who are unsuitable for other conventional treatment methods. In most cases, ulnohumeral arthrodesis is performed, considering the geometry and the amount of surface area of the distal humerus and proximal ulna. In this report, we present a successful case of the radiohumeral arthrodesis using unilateral external fixation without bone grafting for a patient who sustained severe open communited fracture with transarticular massive bone loss. We decided to fuse the elbow at 70 degrees of flexion, and the forearm was fixed at 80 degrees of pronation. At 13-month after the operation, radiographic evidence of solid enlarged right elbow fusion was gained. At more than three years after operation, we evaluated patient-oriented quantitative functional disability using Disabilities of the Arm, Shoulder and Hand (DASH) to confirm that radiohumeral arthrodesis fixed at this angle could be accepted. This technique can be recommended as a salvage procedure in the face of significant bone loss of the proximal ulna.

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Hironobu Yamada

Saitama Medical University

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Takao Motosuneya

Saitama Medical University

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Motohisa Yashiki

Saitama Medical University

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Naoki Kato

Saitama Medical University

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