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Featured researches published by Eiki Shirasawa.


International Journal of Surgery Case Reports | 2016

Remarkable regression of a giant cell tumor of the cervical spine treated conservatively with denosumab: A case report

Toshiyuki Nakazawa; Gen Inoue; Takayuki Imura; Masayuki Miyagi; Wataru Saito; Takanori Namba; Eiki Shirasawa; Kentaro Uchida; Naonobu Takahira; Masashi Takaso

Highlights • Denosumab induced remarkable regression and surrounding sclerosis of the giant cell tumor at 5th cervical vertebral body six months after the administration and these findings are sustained for two years.• FDG-PET/CT showed significant uptake of the tracer before administration of denosumab but no obvious uptake was noted two years after the administration.• The patient has been asymptomatic for two years since denosumab treatment started without any evidence of the recurrence of the giant cell tumor.


Brain and behavior | 2015

Treatment of nocturnal leg cramps by blockade of the medial branch of the deep peroneal nerve after lumbar spine surgery.

Takayuki Imura; Gen Inoue; Toshiyuki Nakazawa; Masayuki Miyagi; Wataru Saito; Kentaro Uchida; Takanori Namba; Eiki Shirasawa; Naonobu Takahira; Masashi Takaso

Patients with lumbar spine disease sometimes complain of nocturnal leg cramps. We sought to investigate the effectiveness of blocking the medial branch of the deep peroneal nerve as treatment for nocturnal leg cramps after spinal surgery for lumbar spine disease.


Spine Surgery and Related Research | 2018

Spontaneous Spinal Epidural Hematoma in an Infant with Developmental Disabilities

Manabu Mukai; Masayuki Miyagi; Tomohisa Koyama; Takayuki Imura; Kuniaki Nakahara; Toshiyuki Nakazawa; Gen Inoue; Wataru Saito; Eiki Shirasawa; Kentaro Uchida; Masashi Takaso

Introduction Spontaneous spinal epidural hematomas (SSEHs) are rare in childhood, especially in infants. Case Report We present the case of a 17-month-old-boy with trisomy 21 and a large SSEH. He was hospitalized for acute onset paraplegia after 6 days of irritability. Nine days after symptom onset, magnetic resonance imaging (MRI) of the spine revealed an extensive epidural hematoma between C7 and T5 causing severe spinal cord compression. After a coagulation disorder was ruled out (12 days after onset), he underwent emergency hemilaminectomy with evacuation of the hematoma. His neurologic impairment gradually improved, and 4 months after surgery he was back to his neurologic baseline. At 18 months after surgery, he was walking independently, although he had some developmental disabilities due to trisomy 21. Conclusions Only 20 cases of SSEH in infancy have been previously reported, and this is the first report of SSEH in an infant with developmental disabilities. Because of the non-specific symptoms and difficulty obtaining MRIs in infants, particularly in those with developmental disabilities, the diagnosis and treatment of SSEH may be delayed. However, early diagnosis with MRI and early evacuation of SSEH in patients with severe neurological impairments is important for good outcomes. Attention must be paid to postoperative spinal deformity in infants.


Spine Surgery and Related Research | 2018

Safety and Efficacy of Treatment for Scolios Is Secondary to Spinal Muscular Atrophy Fused to Lumbar 5 Level

Shoichiro Takei; Masayuki Miyagi; Wataru Saito; Takayuki Imura; Gen Inoue; Toshiyuki Nakazawa; Eiki Shirasawa; Kentaro Uchida; Tsutomu Akazawa; Naonobu Takahira; Masashi Takaso

Introduction Patients with spinal muscular atrophy (SMA) usually have progressive scoliosis. Although fusion of the sacrum or pelvis has been recommended for correcting pelvic obliquity (PO), the procedure is invasive. This study determined as to whether performing instrumentation to the fifth lumbar vertebra (L5) is safe and effective for scoliosis in patients with SMA. Methods Twelve patients with SMA underwent posterior spinal fusion and stopping instrumentation at the L5 level. We evaluated age at surgery, the duration of surgery, blood loss, complications, preoperative and postoperative Cobb angles, and PO. Results The mean age at surgery was 11.4 years; the mean duration of surgery was 319 minutes, and the mean blood loss was 1170 mL. The Cobb angle improved from 97.3° to 39.1° at 1 month postoperatively (correction rate, 60.9%) and to 42.3° at the final follow-up. PO was corrected from 27.8° to 13.1° at 1 month postoperatively (correction rate, 51.7%) and to 19.8° at the final follow-up. No complications were reported. All patients showed improvement in low back pain, with reduced difficulty while sitting. However, >10% correction loss of PO was observed in 6 patients with high preoperative PO. Conclusions The correction rate of scoliosis in SMA patients with posterior spinal fusion and instrumentation to the L5 level was acceptable, and no complications occurred. Scoliosis associated with SMA was more rigid and severer than scoliosis associated with Duchenne muscular dystrophy. Correction rates of the Cobb angle and PO in SMA patients with instrumentation to L5 were similar to those in SMA patients with instrumentation to the sacrum or pelvis. Correction loss of PO was greater in patients with high preoperative PO than in those with low preoperative PO. Instrumentation and fusion to L5 for scoliosis in patients with SMA seems safe and effective, except in cases of high preoperative PO.


Spine Surgery and Related Research | 2018

Perioperative Complications in Posterior Spinal Fusion Surgery for Neuromuscular Scoliosis

Mitsuyoshi Matsumoto; Masayuki Miyagi; Wataru Saito; Takayuki Imura; Gen Inoue; Toshiyuki Nakazawa; Eiki Shirasawa; Kentaro Uchida; Tsutomu Akazawa; Naonobu Takahira; Masashi Takaso

Introduction Patients with neuromuscular disorders sometimes show progressive spinal scoliosis. The surgery for neuromuscular scoliosis (NMS) has high rates of complications. In this study, we elucidated the perioperative complications in patients with NMS. Methods We included 83 patients with NMS (58 boys and 25 girls; 61 with muscular dystrophy, 18 with spinal muscular atrophy, and 4 others) who had undergone posterior fusion surgery for scoliosis. We evaluated the perioperative complications (within 3 months), age at time of surgery, operative time, blood loss, preoperative %VC and FEV1.0 (%) for pulmonary function, and preoperative ejection fraction (EF) for cardiac function. Results There were 5 (6%) major complications, including pneumonia and a cardiovascular complication requiring intensive care unit (ICU) care, and 15 (18%) minor complications including viral enteritis and a urinary tract infection. Overall, there were 20 (24%) complications. Three of the 5 major complications were pulmonary. The mean age at the time of surgery was 13.7 y, operative time was 304 min, and blood loss was 1530 ml. The mean preoperative %VC was 41%, FEV1.0 was 91%, and EF was 60%. When we separated the patients into a group with major complications (n = 5) and a group without major complications (n = 78), the preoperative %VC in the group with major complications (23%) was significantly lower than that in the group without (42%) (p < 0.05). However, operative time, blood loss, preoperative FEV1.0 (%) and EF between the two groups were not significantly different (p > 0.05). Conclusions Compared with the previous findings of the perioperative complication rate (45%-74%) for NMS, the complication rate was remarkably low in this case series. Because of advances in medical skills, including anesthesia and surgical instruments, surgery for NMS appears to be safe. However, patients with NMS with complications demonstrated severe restrictive ventilatory impairment preoperatively. Therefore, we should be vigilant for perioperative pulmonary complications especially in patients with NMS and preoperative severe restrictive ventilatory impairment.


Spine Surgery and Related Research | 2018

The Relationship between Preoperative Echocardiographic Evaluation and Spinal Deformity in Patients with Neuromuscular Scoliosis

Wataru Saito; Gen Inoue; Takayuki Imura; Toshiyuki Nakazawa; Masayuki Miyagi; Eiki Shirasawa; Akiyoshi Kuroda; Kentaro Uchida; Masashi Takaso

Introduction Echocardiography is an important component of perioperative cardiac risk stratification in patients with neuromuscular scoliosis (NMS). However, there are little data regarding the relationship between preoperative echocardiographic findings and spinal deformity. We retrospectively reviewed preoperative echocardiographic data to investigate the relationship between echocardiographic evaluation and spinal deformity in NMS. Methods We reviewed 73 NMS patients (mean age: 13.3 years, male 66%) who underwent spinal correction surgery between 2008 and 2016. Echocardiographic data including ejection fraction (EF), valvar disease, and inferior vena cava diameter were collected from the preoperative exam. Demographic and radiographic data were also collected. Results Preoperative diagnoses included Duchenne muscular dystrophy, Fukuyama congenital muscular dystrophy, other dystrophy, spinal muscular atrophy, and congenital myopathies. Mean Body Mass Index (BMI) was 15.6 kg/m2. Mean major Cobb angle before surgery was 86.6 ± 28.2°. Because of technical difficulty, complete echocardiographic data could only be collected and evaluated in 49.3% of patients. Neither right nor left sided cardiac evaluation could be completed in 20.5%. Patients in whom complete echocardiographic data could not be collected had significantly more extensive thoracic scoliosis with a more rigid curve and hypokyphosis, and were of lower weight and BMI than patients in whom complete data could be collected. Ten cases (13.7%) were diagnosed as having minor heart-related complications immediately after surgery, and they had higher right atrial pressures preoperatively. Conclusions Echocardiography can be technically difficult in NMS patients with extensive spinal deformities. We found that perioperative cardiac function could only be evaluated by echocardiogram in about half of NMS patients undergoing spinal correction surgery. The absence of an adequate preoperative cardiac evaluation could render these patients more susceptible to perioperative heart-related complications. Echocardiography may not be sufficient to evaluate cardiac conditions in children with extensive NMS.


Global Spine Journal | 2018

Radiographic and Clinical Outcomes From the Use of S2 Alar Screws in Surgery for Adult Spinal Deformity

Toshiyuki Nakazawa; Gen Inoue; Takayuki Imura; Masayuki Miyagi; Wataru Saito; Eiki Shirasawa; Kentaro Uchida; Naonobu Takahira; Masashi Takaso

Study Design: Retrospective. Objectives: To evaluate the efficacy of S2 alar screws in surgery for correction of adult spinal deformity (ASD). Methods: We retrospectively reviewed the cases of 23 patients (mean follow-up: 18.5 months, minimum 12 months) who underwent corrective surgery for ASD using S2 alar screws as anchors for instrumentation of lower vertebrae. The background of the patients and their spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], lumbar lordosis [LL], thoracic kyphosis [TK], sagittal vertical axis [SVA], and PI-LL) were evaluated. Results: LL was improved from 9.7 ± 20.5° and SVA from 141.0 ± 64.0 mm before surgery to 39.0 ± 9.6° and 51.7 ± 40.8 mm immediately after surgery, respectively, and 38.2 ± 12.7° and 70.5 ± 59.2 mm at final follow-up. In 13 patients without sufficient correction (postoperative PI-LL ≥10°), bone mineral density and postoperative LL were significantly less, and PI, PI-LL, and PT were significantly greater than in patients with postoperative PI-LL <10°, suggesting that these are risk factors for undercorrection. In 5 patients, SVA increased more than 40 mm during follow-up. Postoperative LL was significantly less (31.4° vs 41.0°) and postoperative PI-LL was significantly greater (21.6° vs 9.3°) in these patients, suggesting a PI-LL mismatch induces postoperative progression of global malalignment. Conclusions: Use of S2 alar screws as anchors for instrumentation in ASD surgery should be restricted. Their use might be an option for patients with low PI, and without severe osteoporosis, in whom efficient surgical correction can be obtained.


Archives of Orthopaedic and Trauma Surgery | 2018

Relationship between spinal sagittal alignment and acetabular coverage: a patient-matched control study

Kensuke Fukushima; Masayuki Miyagi; Gen Inoue; Eiki Shirasawa; Katsufumi Uchiyama; Naonobu Takahira; Masashi Takaso

IntroductionThe significance of the relationship between the spine and hip joints has been frequently discussed. However, the relationship between acetabular coverage and spinal sagittal alignment has not been fully elucidated as previous studies did not adequately control for factors that might affect the spinopelvic alignment. The aim of this study was to elucidate the impact of acetabular coverage on spinal sagittal alignment by comparing patient groups matched on sex, age, and the presence of hip and anterior impingement pain.Materials and methodsWe prospectively enrolled 30 women undergoing periacetabular osteotomy (PAO) for developmental dysplasia of the hip (DDH) and 30 women undergoing hip arthroscopic surgery (HAS) for labral tears. The lateral centre edge angle was measured on hip radiographs. In addition, the sagittal vertical axis, pelvic tilt, pelvic incidence, sacral slope (SS), and lumbar lordosis (LL) were measured on preoperative plain radiographs of the whole spine to assess the sagittal spinal alignment. Clinical and radiologic data were compared between the two groups (PAO vs. HAS).ResultsThe patient groups did not differ in age and body mass index. The mean SS was significantly greater in the PAO group (41.6° ± 1.6°) than in the HAS group (35.3° ± 1.5°; P = 0.0039). Additionally, the mean LL was significantly greater in the PAO group (54.5° ± 2.0°) than in the HAS group (45.1° ± 1.9°; P = 0.0015).ConclusionsThe SS and LL were greater in patients with DDH than in patients with hip pain, but without DDH. Patients with DDH might show lumbar hyperlordosis to rotate the pelvis anteriorly, increasing the anterosuperior acetabular coverage.


Spine Surgery and Related Research | 2017

Surgical treatment for suicidal jumper's fracture (unstable sacral fracture) with thoracolumbar burst fracture: a report of three cases

Shotaro Fujino; Masayuki Miyagi; Shuichiro Tajima; Takayuki Imura; Ryo Tazawa; Gen Inoue; Toshiyuki Nakazawa; Wataru Saito; Eiki Shirasawa; Hiroaki Minehara; Terumasa Matsuura; Tadashi Kawamura; Kentaro Uchida; Naonobu Takahira; Masashi Takaso

Introduction Suicidal jumpers fracture (unstable sacral fracture) is characterized not only by multiple fractures including thoracolumbar fractures, but also major chest and abdominal injuries. Early stabilization of these fractures and early ambulation are required for the treatment and management of chest and abdominal injuries. We present 3 cases of suicidal jumpers fracture with thoracolumbar burst fracture, treated with minimally invasive posterior fixation surgery, which is a combination of percutaneous pedicle screws (PPS) and the mini-open Galveston technique. Case reports Case 1. A 50-year-old woman was injured by a fall from the 5th floor of a building as the result of a suicide attempt. Computed tomography revealed an H-shaped unstable sacral fracture and thoracolumbar fractures with major chest and abdominal injuries. For early stabilization of spinopelvic instability and early ambulation, we treated the patient with PPS and the mini-open Galveston technique. Her early postoperative emergence from bedrest contributed to the improvement of her general condition. One year after surgery at the final follow-up, she was able to walk with a T-cane without any motor, bladder, or bowel dysfunction (BBD) and achieved almost complete healing of the fractures. Cases 2 and 3. A 25-year-old woman (Case 2) and a 43-year-old woman were injured in falls. They had multiple injuries including unstable sacral fractures, and thoracolumbar fractures with major chest and abdominal injuries. We treated these patients with PPS and the mini-open Galveston technique. One year after surgery, they were able to walk with a T-cane and achieved almost complete healing of thoracolumbar fractures, but delayed healing of an unstable sacral fracture in Case 2, and remaining BBD in Case 3. Conclusion PPS and the mini-open Galveston technique is a good approach to fixation because they are minimally invasive and provide moderately rigid fixation, especially in patients with multiple trauma whose general condition is poor.


Journal of Orthopaedic Science | 2017

Common iliac vein injury during L5-S1 posterior lumbar interbody fusion in a patient with systemic lupus erythematosus receiving steroid treatment: A case report.

Wataru Saito; Gen Inoue; Toshiyuki Nakazawa; Takayuki Imura; Masayuki Miyagi; Kentaro Uchida; Takanori Namba; Eiki Shirasawa; Naonobu Takahira; Masashi Takaso

Major vessel injuries following lumbar spinal surgery have been reported [1e12]. Vascular repair is mandatory in such injuries because of the associated high mortality rate [1,2,4,6]. Here we report a common iliac vein injury that occurred during L5eS1 posterior lumbar interbody fusion surgery in a patient with systemic lupus erythematosus taking corticosteroids who was treated successfully with endovascular stent grafting.

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Tsutomu Akazawa

St. Marianna University School of Medicine

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