Hemilaminectomy for Removal of Extramedullary or Extradural Spinal Cord Tumors: Medium to Long-Term Clinical Outcomes

Toshitaka Naganawa,Kei Miyamoto,Hideo Hosoe,Naoki Suzuki,Katsuji Shimizu 연세대학교의과대학 2011 Yonsei medical journal Vol.52 No.1

Purpose: Laminectomy is generally the treatment of choice for removal of spinal tumors. However, it has been shown that laminectomy may cause instability due to damage of posterior elements of the spinal column, which may induce subsequent kyphosis in the future. Therefore, to reduce the risk of deformity and spinal instability after laminectomy, hemilaminectomy has been used. However, the medium to long-term effects of hemilaminectomy on spinal sagittal alignment is not well understood. The present study was performed to evaluate the clinical outcomes, including spinal sagittal alignment of patients, associated with spinal cord tumors treated by surgical excision using hemilaminectomy. Materials and Methods: Twenty hemilaminectomy operations at our institute for extramedullary or extradural spinal cord tumors in 19 patients were evaluated retrospectively with an average follow-up of 85 months (range, 40-131 months). Neurological condition was evaluated using the improvement ratio of the Japanese Orthopaedic Association Score (JOA score) for cervical, thoracic myelopathy, or back pain, and sagittal alignment by sagittal Cobb angle of the hemilaminectomied area. Results: The mean improvement ratio of neurological results was 56.7% in the cervical spine (p < 0.01, n = 10), 26.3% in the thoracic spine (not significant, n = 5), and 48.6% in the lumbar spine (NS, n = 5). The sagittal Cobb angle was 4.3 ± 18.0° in the preoperative period and 5.4 ± 17.6° at the latest follow-up, indicating no significant deterioration. Conclusion: Hemilaminectomy is useful for extramedullary or extradural spinal cord tumors in providing fair neurological status and restoration of spinal sagittal alignment in medium to long-term follow-up.

Comparison of Magnetic Resonance Imaging and Computed Tomography-Myelography for Quantitative Evaluation of Lumbar Intracanalar Cross-Section

Hiroyasu Ogura,Kei Miyamoto,Shoji Fukuta,Toshitaka Naganawa,Katsuji Shimizu 연세대학교의과대학 2011 Yonsei medical journal Vol.52 No.1

Purpose: A comparison of MRI and computed tomography-myelography (CTM) for lumbar intracanalar dimensions. To compare the capability and reproducibility of MRI and CTM in measuring the cross-sectional morphology of intracanalar lesions of the lumbar spine. Materials and Methods: MRI and CTM of lumbar disc levels from 61 subjects with various lumbar spinal diseases were studied. Dural area, dural anteroposterior (AP) diameter, dural right-left diameter, and thickness of the ligamentum flavum were measured by two orthopedic surgeons. Each section was graded by degree of stenosis. Absolute value and intra- and inter-observer correlation coefficients (ICC) of these measurements and the associations between MRI and CTM values were determined. Results: Except for MRI determination of ligament flavum thickness, CTM and MRI and intra- and ICC suggested sufficient reproducibility. When measurements of dural area, dural AP diameter, and RL diameter were compared, values in CTM were significantly (p = 0.01-0.004) larger than those in MRI (CTM/MRI ratios, 119%, 111%, and 105%, respectively). As spinal stenosis became more severe, discrepancies between CTM and MRI in measurements of the dural sac became larger. Conclusion:Both CTM and MRI provided reproducible measurements of lumbar intracanalar dimensions. However, flavum thickness may be more accurately measured by CTM. Because the differences in the measurements between CTM and MRI are very slight and there is very little data to suggest that the precise degree of stenosis is related to symptoms or treatment outcome, the usefulness of the CTM over MRI needs to be confirmed in future studies.

Clinical Outcomes of Surgical Treatments for Traumatic Spinal Injuries due to Snowboarding

Takahiro Masuda,Kei Miyamoto,Kazuhiko Wakahara,Kazu Matsumoto,Akira Hioki,Tetsuya Shimokawa,Katsuji Shimizu,Shinji Ogura,Haruhiko Akiyama 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.1

Study Design: Retrospective study. Purpose: To assess treatment outcomes of snowboarding-related spinal and spinal cord injuries. Overview of Literature: Snowboarding-related spinal or spinal cord injury have a great impact on social and sporting activities. Methods: A retrospective review of 19 cases of surgically treated snowboard-related injury was done. Analyzed parameters included site of injury, type of fracture, peri- and postoperative complications, pre- and postoperative neurological status, activities of daily living, and participation in sports activities at the final follow-up. Results: The major site of injury was the thoracolumbar junction caused by fracture-dislocation (13/19 cases). The remaining 6 cases had cervical spine injuries. Over 60% of the patients had Frankel A and B paralysis. All patients were surgically treated by posterior fusion with instrumentation. Five underwent additional anterior fusion. Surgical outcome was restoration of ambulatory capacity in 12 patients (63.2%). Ultimately, 15 patients (78.9%) could return to work. Patients with complete paralysis upon admission showed reduced ambulatory capacity compared to those with incomplete paralysis. None of the patients again participated in any sports activities, including snowboarding. Conclusions: Snowboarding-related spinal or spinal cord injury has a great impact on social as well as sports activities. It is necessary to enhance promotion of injury prevention emphasizing the snowboarders’ responsibility code.

Cervical Symmetric Dumbbell Ganglioneuromas Causing Severe Paresis

Akira Hioki,Kei Miyamoto,Yoshinobu Hirose,Yusuke Kito,Kazunari Fushimi,Katsuji Shimizu 대한척추외과학회 2014 Asian Spine Journal Vol.8 No.1

We report an extremely rare case with bilateral and symmetric dumbbell ganglioneuromas of the cervical spine in an elderly patient. A 72-year-old man came by ambulance to our hospital due to progressive incomplete paraplegia. Magnetic resonance imaging demonstrated bilateral symmetric dumbbell tumors at the C1/2 level. We performed total resection of the intracanalar tumor, aiming at complete decompression of the spinal cord, and partial and subtotal resection of foraminal outside portions. Histopathological examination of the surgical specimen indicated the tumor cells to be spindle cells with the presence of ganglion cells and no cellular pleomorphism, suggesting a diagnosis of ganglioneuroma. Although the surgery was not curative, the postoperative course was uneventful and provided a satisfactory outcome. This is the fourth known case of cervical ganglioneuromas of the bilateral symmetric dumbbell type.

Sagittal Alignment of a Strut Graft Affects Graft Subsidence and Clinical Outcomes of Anterior Cervical Corpectomy and Fusion

Koun Yamauchi,Kazunari Fushimi,Kei Miyamoto,Akira Hioki,Katsuji Shimizu,Haruhiko Akiyama 대한척추외과학회 2017 Asian Spine Journal Vol.11 No.5

Study Design: Retrospective study. Purpose: The purpose of this study was to investigate the influence of sagittal alignment of the strut graft on graft subsidence and clinical outcomes after anterior cervical corpectomy and fusion (ACCF). Overview of Literature: ACCF is a common technique for the treatment of various cervical pathologies. Although graft subsidence sometimes occurs after ACCF, it is one cause for poor clinical results. Malalignment of the strut graft is probably one of the factors associated with graft subsidence. However, to the best of our knowledge, no prior reports have demonstrated correlations between the alignment of the strut graft and clinical outcomes. Methods: We evaluated 56 patients (33 men and 23 women; mean age, 59 years; range, 33–84 years; 45 with cervical spondylotic myelopathy and 11 with ossification of the posterior longitudinal ligament) who underwent one- or two-level ACCF with an autogenous fibular strut graft and anterior plating. The Japanese Orthopaedic Association (JOA) score recovery ratio for cervical spondylotic myelopathy was used to evaluate clinical outcomes. The JOA score and lateral radiograms were evaluated 1 week and 1 year postoperatively. Patients were divided into two groups (a straight group [group I] and an oblique group [group Z]) based on radiographic assessment of the sagittal alignment of the strut graft. Results: Group I showed a significantly greater JOA score recovery ratio (p <0.05) and a significantly lower graft subsidence than group Z (p <0.01). Conclusions: Our findings suggest that a straight alignment of the strut graft provides better clinical outcomes and lower incidence of graft subsidence after ACCF. In contrast, an oblique strut graft can lead to significantly increased strut graft subsidence and poor clinical results.

Cantilever Transforaminal Lumbar Interbody Fusion for Upper Lumbar Degenerative Diseases (Minimum 2 Years Follow Up)

Akira Hioki,Kei Miyamoto,Hideo Hosoe,Seiichi Sugiyama,Naoki Suzuki,Katsuji Shimizu 연세대학교의과대학 2011 Yonsei medical journal Vol.52 No.2

Purpose: To evaluate the clinical outcomes of cantilever transforaminal lumbar interbody fusion (c-TLIF) for upper lumbar diseases. Materials and Methods: Seventeen patients (11 males, 6 females; mean ± SD age: 62 ± 14 years) who underwent c-TLIF using kidney type spacers between 2002 and 2008 were retrospectively evaluated,at a mean follow-up of 44.1 ± 12.3 months (2 year minimum). The primary diseases studied were disc herniation, ossification of posterior longitudinal ligament (OPLL), degenerative scoliosis, lumbar spinal canal stenosis, spondylolisthesis, and degeneration of adjacent disc after operation. Fusion areas were L1-L2 (5 patients), L2-L3 (9 patients), L1-L3 (1 patient), and L2-L4 (2 patients). Operation time, blood loss, complications, Japanese Orthopaedic Association (JOA) score for back pain, bone union, sagittal alignment change of fusion level, and degeneration of adjacent disc were evaluated. Results: JOA score improved significantly after surgery, from 12 ± 2 to 23 ± 3 points (p < 0.01). We also observed significant improvement in sagittal alignment of the fusion levels, from - 1.0 ± 7.4 to 5.2 ± 6.1 degrees (p < 0.01). Bony fusion was obtained in all cases. One patient experienced a subcutaneous infection, which was cured by irrigation. At the final follow-up, three patients showed degenerative changes in adjacent discs, and one showed corrective loss of fusion level. Conclusion: c-TLIF is a safe procedure, providing satisfactory results for patients with upper lumbar degenerative diseases.