Spinal Metastasis from Struma Ovarii: Case Report and Review of the Literature

Kazuyoshi Kobayashi,Shiro Imagama,Shin Tsunekawa,Kaori Hosokawa,Minemori Watanabe,Zenya Ito,Kei Ando,Naoki Ishiguro 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.2

Struma ovarii is a rare tumor that is defined as an ovarian teratoma with a thyroid tissue component exceeding 50%. Most of these tumors are benign, with malignant struma ovarii occurring in <1% of patients. Here, we describe the case of a 49-year-old female patient with malignant struma ovarii who developed thoracic spine metastasis. She had undergone an oophorectomy and was diagnosed with struma ovarii 10 years previously. She had remained recurrence-free thereafter. At 49 years of age, she developed low back pain and was admitted to our hospital for evaluation of a spinal tumor at the Th7 level. An emergency bone biopsy led to a diagnosis of metastasis from malignant struma ovarii. External beam radiotherapy inhibited further tumor growth and there was no resulting muscle weakness. This is the first report of spinal metastasis occurring 10 years after resection of struma ovarii, indicating the need for long-term follow-up.

Progressive Relapse of Ligamentum Flavum Ossification Following Decompressive Surgery

Kei Ando,Shiro Imagama,Zenya Ito,Kazuyoshi Kobayashi,Junichi Ukai,Akio Muramoto,Ryuichi Shinjo,Tomohiro Matsumoto,Hiroaki Nakashima,Naoki Ishiguro 대한척추외과학회 2014 Asian Spine Journal Vol.8 No.6

Thoracic ossification of the ligamentum flavum (T-OLF) is a relatively rare spinal disorder that generally requires surgical intervention, due to its progressive nature and the poor response to conservative therapy. The prevalence of OLF has been reported at 3.8%–26%, which is similar to that of cervical ossification of the posterior longitudinal ligament (OPLL). The progression of OPLL after cervical laminoplasty for the treatment of OPLL is often shown in long-term follow-up. However, there have been no reports on the progression of OLF following surgery. We report a case of thoracic myelopathy secondary to the progressive relapse of OLF following laminectomy.

Variety of the Wave Change in Compound Muscle Action Potential in an Animal Model

Zenya Ito,Shiro Imagama,Kei Ando,Akio Muramoto,Kazuyoshi Kobayashi,Tetsuro Hida,Kenyu Ito,Yoshimoto Ishikawa,Mikito Tsushima,Akiyuki Matsumoto,Satoshi Tanaka,Masayoshi Morozumi,Yukihiro Matsuyama,Naok 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.6

Study Design: Animal study. Purpose: To review the present warning point criteria of the compound muscle action potential (CMAP) and investigate new criteria for spinal surgery safety using an animal model. Overview of Literature: Little is known about correlation palesis and amplitude of spinal cord monitoring. Methods: After laminectomy of the tenth thoracic spinal lamina, 2–140 g force was delivered to the spinal cord with a tension gage to create a bilateral contusion injury. The study morphology change of the CMAP wave and locomotor scale were evaluated for one month. Results: Four different types of wave morphology changes were observed: no change, amplitude decrease only, morphology change only, and amplitude and morphology change. Amplitude and morphology changed simultaneously and significantly as the injury force increased (p <0.05) Locomotor scale in the amplitude and morphology group worsened more than the other groups. Conclusions: Amplitude and morphology change of the CMAP wave exists and could be the key of the alarm point in CMAP.

Outpatient Myelography: A Prospective Trial Comparing Complications after Myelography between Outpatients and Inpatients in Japan

Tomohiro Matsumoto,Shiro Imagama,Hidenori Inoue,Takaaki Aoki,Naoki Ishiguro,Yoshimitsu Osawa 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.6

Study Design: Prospective comparative study. Purpose: To compare the incidence and severity of adverse reactions associated with myelography performed in outpatients vs. in inpatients and report the safety and usefulness of outpatient myelography in Japanese patients. Overview of Literature: Myelography is normally performed as an inpatient procedure in most hospitals in Japan. No studies have reported the usefulness and adverse effects of outpatient myelography in Japanese patients. Methods: We performed 221 myelography procedures. Eighty-five of the 221 patients underwent outpatient myelography using our new protocol. The incidence and severity of adverse reactions were compared with the other 136 patients, who underwent conventional inpatient myelography. We further compared the cost of outpatient and inpatient myelography. Results: The overall rate of adverse effects was 9.4% in outpatients, as compared with 7.4% in inpatients. Overall, 1.2% of outpatients and 0.74% inpatients experienced “severe” adverse effects (requiring hospitalization). There were no significant differences between the 2 groups in either the overall rate of adverse effects or the rate of “severe” adverse effects. Moreover, the average outpatient procedure cost was only one-third to one-half that of the inpatient procedure. Conclusions: This was the first study to address the safety and usefulness of outpatient myelography in Japanese patients. If selected according to proper inclusion criteria for outpatient procedure, no significant differences were observed in the adverse effects between inpatients and outpatients. The outpatient procedure is more economical and has the added benefit of being more convenient and time-efficient for the patient.

Single-Stage Removal of Thoracic Dumbbell Tumors from a Posterior Approach Only with Costotransversectomy

Kei Ando,Shiro Imagama,Norimitsu Wakao,Kenichi Hirano,Ryoji Tauchi,Akio Muramoto,Hiroki Matsui,Tomohiro Matsumoto,Yukihiro Matsuyama,Naoki Ishiguro 연세대학교의과대학 2012 Yonsei medical journal Vol.53 No.3

Purpose: Thoracic dumbbell tumors are relatively rare, usually arising from neurogenic elements. Methods for surgical removal thereof remain controversial. The purpose of this study was to evaluate the surgical results of a single-stage posterior approach with laminectomy and costotransversectomy only for the management of thoracic dumbbell tumors. Materials and Methods: Eight cases of thoracic large dumbbell tumor were analyzed retrospectively: seven men and one woman (mean age, 49 years). Pathologic findings included schwannoma in five patients, neurofibroma in two patients (Recklinghausen in one patient), and ganglioneuroma in one patient. All patients underwent single-stage removal of dumbbell tumors by a posterior approach followed by laminectomy and costotransversectomy combined with instrumentation. Clinical and radiologic outcomes were reviewed, thereafter. Results: Operative time ranged from 185 to 420 minutes (mean, 313 minutes), with estimated blood loss ranging from 71 to 1830 mL (mean, 658 mL). Postoperative complications included atelectasis in one case. All patients had tumors successfully removed with no neurological deterioration. Spinal deformities were not observed in any patients at the last follow-up (mean, 52 months), with instrumentation. Conclusion: Single-stage surgery with laminectomy and costotransversectomy may be useful for removing thoracic dumbbell tumors without a combined anterior approach.

Perioperative Management of Patients with Hemophilia during Spinal Surgery

Kazuyoshi Kobayashi,Shiro Imagama,Kei Ando,Kenyu Ito,Mikito Tsushima,Masayoshi Morozumi,Satoshi Tanaka,Masaaki Machino,Kyotaro Ota,Yoshihiro Nishida,Naoki Ishiguro 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.3

Study Design: Single-center retrospective study. Purpose: To optimize the perioperative management of patients with hemophilia who are undergoing spinal surgery. Overview of Literature: Hemophilia is a rare disease in which there is a tendency of bleeding because of a congenital deficiency in blood coagulation factor activity. There has been no previous report on spinal surgery in patients with hemophilia. Methods: The subjects were five patients (all males) with hemophilia who underwent spinal surgery at Nagoya University Hospital. Two patients had hemophilia A (deficiency of factor VIII) and three had hemophilia B (deficiency of factor IX). The mean age at the time of surgery was 63 years (range, 46–73 years). The following surgeries were performed: posterior lumbar interbody fusion (PLIF) in two patients, and lumbar fenestration, cervical laminoplasty and lumbar fenestration, and cervical laminoplasty and PLIF in one patient each. Results: Coagulation factor at a mean dose of 4.8 ×103 U (range, 3–6 ×103 U) was intravenously injected before surgery, and a mean dose of 5.2 ×103 U (rang, 4–6 ×103 U) was continuously administered for 24 hours after surgery. Factor activity was maintained at ≥80% until postoperative day 14 and at ≥50% thereafter. The average duration of surgery was 178 minutes (range, 133–233 minutes), the estimated blood loss was 661 mL (range, 272–1,344 mL), and a drain tube was left subfascially in place for 2 days in all patients. Reoperation due to postoperative surgical site infection was required in one patient, but there were no complications due to hemorrhagic diathesis. The total dose of coagulation factor administered during hospitalization was 102 ×103 U (range, 46–198 ×103 U). Conclusions: Coordination with a hematologist and dose adjustment of the coagulation factor preparation to maintain a target level of coagulation factor activity facilitated a smooth postoperative course with perioperative control of bleeding during spinal surgery for patients with hemophilia.

Utility of a Computed Tomography-Based Navigation System (O-Arm) for En Bloc Partial Vertebrectomy for Lung Cancer Adjacent to the Thoracic Spine: Technical Case Report

Kazuyoshi Kobayashi,Shiro Imagama,Zenya Ito,Kei Ando,Kohei Yokoi,Naoki Ishiguro 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.2

We describe successful vertebrectomy from a posterior approach using a computed tomography (CT)-based navigation system (O-arm) in a 53-year-old man with adenocarcinoma of the posterior apex of the right lung with invasion of the adjacent rib, thoracic wall, and T2 and T3 vertebral bodies. En bloc partial vertebrectomy for lung cancer adjacent to the thoracic spine was planned using O-arm. First, laminectomy was performed from right T2 to T3, and pedicles and transverse processes of T2 to T3 were resected. O-arm was used to confirm the location of the cutting edge in the T2 to 3 right vertebral internal body, and osteotomy to the anterior cortex was performed with a chisel. Next, the patient was placed in a left decubitus position. The surgical specimen was extracted en bloc . This case shows that O-arm can be used reliably and easily in vertebrectomy from a posterior approach and can facilitate en bloc resection.

Postoperative Severe Headache Following Cervical Posterior Surgical Fixation from C2 Distally

Ryoji Tauchi,이상훈,Jin-Young Kim,김용찬,Colleen Peters,Shiro Imagama,Naoki Ishiguro,Jacob Buchowski,K. Daniel Riew 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.4

Study Design: Retrospective study. Purpose: To identify the prevalence of severe headache occurring after cervical posterior surgical fixation (PSF) and to evaluate the clinical and radiological findings associated with severe headache after surgery. Overview of Literature: Several studies have reported on the axial pain after cervical surgery. However, to our knowledge, the incidence of severe headache after cervical PSF has not been elucidated. Methods: The medical records and radiological assessment of patients who underwent surgical treatment from August 2002 to May 2012 were reviewed to identify the prevalence and risk factors for severe headaches occurring following PSF from C2 distally. Neck disability index scores (NDI) (the item for neck pain), the type of C2 screw, number of cervical fused levels (1–6), and smoking habit were calculated preoperatively and postoperatively. In addition, radiological parameters (T1 slope angle, C1/2 angle, C2–7 Cobb angle, C2–7 sagittal vertical axis and C1-implant distance) were assessed for all patients. Severe headache was defined as a high NDI headache score (>4 out of 5). Results: Eighty-two patients met the inclusion criteria. The mean age was 59.2 years (range, 21–78 years), and the mean number of fused levels was 5.1. The mean follow-up period was 2.9 years (range, 1–10.9 years). While only one severe headache occurred de novo postoperatively in a patient in the C3 or C4 distally group (total 30 patients, average age of 50.2 years), 11 patients in the C2 distally group (p =0.04) had severe headache occur postoperatively. The radiological parameters were not significantly different between the postoperative milder headache and severe headache (SH) groups. The SH group had a significantly higher preoperative NDI score (neck pain) (p <0.01). Conclusions: Newly occurring severe headaches can occur in 18% of patients after PSF from C2 distally. The patients with newly occurring severe headaches had significantly higher preoperative NDI score (neck pain).

Unplanned Second-Stage Decompression for Neurological Deterioration Caused by Central Canal Stenosis after Indirect Lumbar Decompression Surgery

Hiroaki Nakashima,Tokumi Kanemura,Kotaro Satake,Yoshimoto Ishikawa,Jun Ouchida,Naoki Segi,Hidetoshi Yamaguchi,Shiro Imagama 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.4

Study Design: Prospective cohort study. Purpose: This study aimed to identify risk factors for unplanned second-stage decompression for postoperative neurological deficit after indirect decompression using lateral lumbar interbody fusion (LLIF) with posterior fixation. Overview of Literature: Indirect lumbar decompression with LLIF has been used as a minimally invasive alternative to direct decompression to treat degenerative lumbar diseases requiring neural decompression. However, evidence on the prevalence of neurological deficits caused by spinal canal stenosis after indirect decompression is limited. Methods: This study included 158 patients (mean age, 71.13±7.98 years; male/female ratio, 67/91) who underwent indirect decompression with LLIF and posterior fixation. Indirect decompression was performed at 271 levels (mean level, 1.71±0.97). Logistic regression analysis was used to identify the risk factors for postoperative neurological deficits. The variables included were age, sex, body mass index, presence of primary diseases, diabetes mellitus, preoperative motor deficit, levels operated on, preoperative severity of lumbar stenosis, and preoperative Japanese Orthopedic Association (JOA) score. Results: Postoperative neurological deficit due to spinal canal stenosis occurred in three patients (1.9%). Spinal stenosis due to hemodialysis (p<0.001), ligament ossification (p<0.001), presence of preoperative motor paralysis (p<0.001), low JOA score (p=0.004), and severe canal stenosis (p=0.02) were significantly more frequent in the paralysis group. Conclusions: Severe preoperative canal stenosis and neurological deficit were identified as risk factors for postoperative neurological deterioration caused by spinal canal stenosis. Additionally, uncommon diseases, such as spinal stenosis due to hemodialysis and ligament ossification, increased the risk of postoperative neurological deficit; therefore, in such cases, indirect decompression is contraindicated.

The Prevalence and Risk Factors for S2 Alar-Iliac Screw Loosening with a Minimum 2-Year Follow-up

Hiroaki Nakashima,Tokumi Kanemura,Kotaro Satake,Kenyu Ito,Yoshimoto Ishikawa,Jun Ouchida,Naoki Segi,Hidetoshi Yamaguchi,Shiro Imagama 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.2

Study Design: A retrospective cohort study. Purpose: The purpose of this study was to investigate the prevalence and risk factors for S2 alar-iliac (SAI) screw loosening following lumbosacral fixation, with a minimum 2-year follow-up. Overview of Literature: Although SAI screws allow surgeons to perform lumbosacral fixation with a low profile and enhanced biomechanical strength, screw loosening following surgery can occur in some cases. However, few studies have investigated the prevalence and risk factors for SAI screw loosening. Methods: This retrospective study included 35 patients (mean age, 72.8±8.0 years; male, 10; female, 25) who underwent lumbosacral fixation using SAI screws with at least 2 years of follow-up. SAI screw loosening and L5–S bony fusion were assessed using computed tomography. The period for which the screws appeared loose and the risk factors for SAI screw loosening were investigated 2 years after surgery. Results: A total of 70 SAI screws and 70 S1 pedicle screws were inserted. Loosening was observed 0.5, 1, and 2 years after surgery in 17 (24.3%), 35 (50.0%), and 35 (50.0%) SAI screws, respectively. Bony fusion rate at L5–S was significantly lower in patients with SAI screw loosening than in those without screw loosening (65.0% vs. 93.3%, p=0.048). The score for SAI screw contact with the iliac cortical bone and the bony fusion rate at L5–S were significantly lower in the loosening group than in the non-loosening group (1.8±0.5 vs. 2.2±0.3, p<0.001, respectively). Postoperative pelvic incidence–lumbar lordosis was significantly higher in the loosening group than in the non-loosening group (7.9°±15.4° vs. 0.5°±8.7°, p=0.02, respectively). Conclusions: SAI screw loosening is closely correlated with pseudoarthrosis at L5–S. Appropriate screw insertion and optimal lumbar lordosis restoration are important to prevent postoperative complications related to SAI screws.