Selective Angiography to Detect Anterior Spinal Artery Stenosis in Thoracic Ossification of the Posterior Longitudinal Ligament

Yoshida Go,Ushirozako Hiroki,Hasegawa Tomohiko,Yamato Yu,Yasuda Tatsuya,Banno Tomohiro,Arima Hideyuki,Oe Shin,Mihara Yuki,Yamada Tomohiro,Ide Koichiro,Watanabe Yuh,Ushio Takasuke,Matsuyama Yukihiro 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.3

Study Design: Single-center prospective study.Purpose: To investigate anterior spinal artery (ASA) status using preoperative selective angiography in patients undergoing surgery for thoracic ossification of the posterior longitudinal ligament (T-OPLL).Overview of Literature: Surgery for T-OPLL has a high risk of neurological complications, which might be associated with insufficient spinal cord blood flow.Methods: This study prospectively examined nine T-OPLL patients who underwent posterior thoracic decompression with kyphosis correction and instrumented fusion at Hamamatsu University School of Medicine between 2017 and 2019. All underwent preoperative selective angiography to detect and evaluate the Adamkiewicz artery and ASA. Intraoperative neuromonitoring and Doppler ultrasonography were performed to analyze neurological complications and spinal cord blood flow.Results: All nine patients showed ASA stenosis in the area of T-OPLL. In all patients, the Adamkiewicz artery was located between T7 and L2 and the area of ASA stenosis corresponded to the level of T-OPLL and greatest spinal cord compression; intraoperative Doppler ultrasonography confirmed the ASA defect at the same spinal level. The number of spinal levels from the Adamkiewicz artery to the most compressive OPLL lesion was greater in the two patients who developed postoperative neurological deficit compared to those who did not (5.5 vs. 2.3, p=0.014).Conclusions: This is the first study to report detection of ASA stenosis in patients with T-OPLL. Maintaining spinal cord blood flow is important in these patients to avoid neurological deterioration.

Minimum Clinically Important Differences in Oswestry Disability Index Domains and Their Impact on Adult Spinal Deformity Surgery

Go Yoshida,Tomohiko Hasegawa,Yu Yamato,,Sho Kobayashi,Oe Shin,Tomohiro Banno,Yuuki Mihara,Hideyuki Arima,Hiroki Ushirozako,Tatsuya Yasuda,Daisuke Togawa,Yukihiro Matsuyama 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.1

Study Design: Retrospective study. Purpose: To calculate the minimum clinically important difference (MCID) for total and individual domains of the Oswestry Disability Index (ODI) and assess score distribution and changes over time in surgically treated adult spinal deformity (ASD) patients. Overview of Literature: Despite the common use of ODI for assessing ASD, there are no robust studies defining MCID values for this index. Methods: This study included 240 consecutive ASD patients with a minimum of 2 years of follow-up. We calculated MCID values for total and individual ODI domains using all or part of the Scoliosis Research Society-22R questionnaire as anchors. Using current MCID values, we measured the acquisition rates in patients who acquired MCID at follow-up in both total and individual ODI domains. Differences in pathology, age, and locations of the upper and lower instrumented vertebrae were analyzed. Results: MCID of the total ODI score was 11%, with an area under the curve of 0.737. Each domain ranged from 0 to 2, with 1 being the most common value. In the pain and standing domains, >60% of the patients acquired MCID, although acquisition rates of the personal care, lifting, sleep, and sexual activity domains were relatively low (20%–35%). Patients with MCID had more radiographic improvement in lumbar lordosis, sagittal vertical axis, and T1 pelvic angle than those without MCID (p <0.05). Conclusions: To our knowledge, this is the first study to describe MCID of ODI (11%) after ASD surgery. In the pain and standing domains, most patients acquired MCID although the rates of acquisition of MCID in the personal care, lifting, sleep, and sexual activity domains were low. Spine surgeons should counsel their patients regarding the benefits and setbacks of ASD surgery.

Novel Measurement Technique for the Sagittal Vertical Axis and Its Clinical Application in Adult Spinal Deformity

Go Yoshida,Kenta Kurosu,Yu Yamato,Tomohiko Hasegawa,Tatsuya Yasuda,Daisuke Togawa,Yukihiro Matsuyama 대한척추외과학회 2017 Asian Spine Journal Vol.11 No.2

Study Design: Prospective physical measurement of the sagittal vertical axis (SVA). Purpose: To evaluate a simple method for measuring SVA by analyzing its relationship with radiographic measurements and clinical appearance. Overview of Literature: No studies have examined physical measurements using the cranial center of gravity (CCG) in a relaxed standing position. Methods: The physical measurement of the horizontal distance between CCG and spina iliaca posterior superior (CCG-SIPS) was measured using a straight ruler in 252 healthy volunteers and 56 patients with adult spinal deformity. Health-related quality of life (HRQOL) was evaluated using the Oswestry disability index (ODI), and clinical symptoms were assessed according to standing status and the presence of gastroesophageal reflux disease (GERD). Results: CCG-SIPS increased with age in the volunteer group and strongly correlated with radiographic SVA in the patient group (r =0.984). Differences increased between CCG-SIPS in patients in the relaxed position and radiographic SVA with an increase in sagittal malalignment (r =0.692, p <0.001). ODI with high sagittal malalignment (CCG-SIPS >120 mm) was significantly larger in the patient group than in the group with low sagittal malalignment (59.9±18.8 vs. 45.1±17.0; p =0.004); these patients (CCG-SIPS >120 mm) needed crutches or walkers for standing. The patient group with GERD had significantly larger sagittal malalignment than the group without GERD (160.3 mm vs. 81.0 mm). Conclusions: The CCG-SIPS correlated with age and strongly reflected radiographic SVA and HRQOL in the patients. Moreover, it reflects a relaxed posture without a backward shift in the radiographic position even in patients with severe sagittal malalignment. The critical limit of CCG-SIPS can be relevant to clinical appearance, including standing assistance (>120 mm) and the existence of GERD (>150 mm). Thus, it will be a useful predictor of true SVA in clinical practice before radiographic evaluation.

Accuracy of Percutaneous Lumbosacral Pedicle Screw Placement Using the Oblique Fluoroscopic View Based on Computed Tomography Evaluations

Go Yoshida,Koji Sato,Tokumi Kanemura,Toshiki Iwase,Daisuke Togawa,Yukihiro Matsuyama 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.4

Study Design: Retrospective. Purpose: This study aims to investigate the accuracy of the oblique fluoroscopic view, based on preoperative computed tomography (CT) images for accurate placement of lumbosacral percutaneous pedicle screws (PPS). Overview of Literature: Although PPS misplacement has been reported as one of the main complications in minimally invasive spine surgery, there is no comparative data on the misplacement rate among different fluoroscopic techniques, or comparing such techniques with open procedures. Methods: We retrospectively selected 230 consecutive patients who underwent posterior spinal fusion with a pedicle screw construct for degenerative lumbar disease, and divided them into 3 groups, those who had undergone: minimally invasive percutaneous procedure using biplane (lateral and anterior-posterior views using a single C-arm) fluoroscope views (group M-1), minimally invasive percutaneous procedure using the oblique fluoroscopic view based on preoperative CT (group M-2), and conventional open procedure using a lateral fluoroscopic view (group O: controls). The relative position of the screw to the pedicle was graded for the pedicle breach as no breach, <2 mm, 2–4 mm, or >4 mm. Inaccuracy was calculated and assessed according to the spinal level, direction and neurological deficit. Inter-group radiation exposure was estimated using fluoroscopy time. Results: Inaccuracy involved an incline toward L5, causing medial or lateral perforation of pedicles in group M-1, but it was distributed relatively equally throughout multiple levels in groups M-2 and controls. The mean fluoroscopy time/case ranged from 1.6 to 3.9 minutes. Conclusions: Minimally invasive lumbosacral PPS placement using the conventional fluoroscopic technique carries an increased risk of inaccurate screw placement and resultant neurological deficits, compared with that of the open procedure. Inaccuracy tended to be distributed between medial and lateral perforations of the L5 pedicle, as a result of pedicle morphology and the PPS pathway. Oblique fluoroscopic views, based on CT measurement, may allow accurate PPS insertion with a shorter fluoroscopy time.

An Efficient Substrate Bias Generator with CMOS Double Charge-Pumping Circuit

Yasoji Suzuki,Masahiro Yoshida,Mitsuo Teramoto,Yukihiro Saeki,Shinichi Saitoh 대한전자공학회 1997 ITC-CSCC :International Technical Conference on Ci Vol.- No.-

Revision Surgery for a Rod Fracture with Multirod Constructs Using a Posterior-Only Approach Following Surgery for Adult Spinal Deformity

Yamato Yu,Hasegawa Tomohiko,Yoshida Go,Banno Tomohiro,Oe Shin,Arima Hideyuki,Mihara Yuki,Ushirozako Hiroki,Yamada Tomohiro,Watanabe Yuh,Ide Koichiro,Nakai Keiichi,Kurosu Kenta,Matsuyama Yukihiro 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.5

Study Design: Single-center retrospective case series.Purpose: We aimed to evaluate the clinical results of revision surgery for a rod fracture using a posterior-only approach and determine the best procedure to prevent refracture in patients with adult spinal deformity (ASD).Overview of Literature: ASD affects the thoracolumbar spine and often requires surgical correction. However, surgery for extensive spinal fusion causes rod fracture, a major mechanical complication. Few studies have described the treatment methods for rod fractures. Furthermore, the clinical outcomes of revision surgery for rod fractures in patients with ASD are currently unclear.Methods: We retrospectively reviewed the medical records of 404 patients who underwent corrective fusion surgery for ASD with a minimum 2-year follow-up. We studied cases of reoperation for postoperative rod fractures and investigated surgical procedure, intraoperative findings, clinical course, and rod refracture following revision surgery.Results: Rod fracture was observed in 88 patients (21.8%). Fifty-three patients (average age, 68.3 years; average blood loss, 502.2 mL [% estimated blood volume=16.4%]; and operation time, 203.3 minutes) who suffered from a rod fracture at an average of 28.3 months after the primary operation underwent reoperation. Surgical invasiveness had no significant differences in total or partial rod replacement; however, the procedures with and without an anterior bone graft significantly differed. The replaced rod refractured at an average of 35.3 months after the revision surgery of five patients. The rod also refractured at a level outside multiple rods in two patients and with traumatic episodes in three patients. Three patients had bone grafts in the anterior column.Conclusions: Revision surgery involving a multirod with a posterior-only approach for a rod fracture that occurred after ASD was performed successfully. Bone grafting in the anterior column is unnecessary for patients without massive bone defects.

Transcranial Motor Evoked Potential Monitoring for the Detection of Nerve Root Injury during Adult Spinal Deformity Surgery

Hiroki Ushirozako,Go Yoshida,Sho Kobayashi,Tomohiko Hasegawa,Yu Yamato,Tatsuya Yasuda,Tomohiro Banno,Hideyuki Arima,Shin Oe,Yuki Mihara,Daisuke Togawa,Yukihiro Matsuyama 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.4

Study Design: Retrospective study. Purpose: We aimed to determine the utility of transcranial motor evoked potential (TcMEP) monitoring for the detection of intraoperative nerve root injury. Overview of Literature: Intraoperative neuromonitoring is important for the prediction of neurological injuries or postoperative paralysis. Nerve root injury can develop as a complication of adult spinal deformity (ASD) surgery. Methods: We analyzed 295 patients who underwent ASD surgery using multi-channel TcMEP monitoring between 2010 and 2016 (58 men, 237 women; median age, 68 years; follow-up period ≥1 year). We defined the alarm point as a TcMEP amplitude <30% of that at baseline, and nerve root injury as meeting the focal TcMEP alerts shortly following surgical procedures with the presence of postoperative motor deficits in the selected muscles. Patients were classified into two groups, as those with nerve root injury and those with true-negatives. Results: Seven patients (2.4%) exhibited neurological events related to nerve root injury, comprising six true-positive and one falsenegative cases. TcMEP monitoring from multiple myotomes was effective in detecting nerve root injury. Compared to the 248 truenegative cases, the seven cases of nerve root injury were associated with significantly different preoperative pelvic tilt (PT) values, sacral slope values, and degree of change in PT. The cutoff for the degree of change in PT for predicting nerve root injury, with the best sensitivity and specificity, was 17.5°. Multivariate logistic analyses revealed that a change of >17.5° in PT (odds ratio, 17.5; 95% confidence interval, 1.994–153.560; p =0.010) was independently associated with intraoperative nerve root injury. Conclusions: Multi-channel TcMEP monitoring may be useful for detecting nerve root injuries. A change in PT of >17.5° may be a significant risk factor for neurological events related to intraoperative nerve root injury.

A New Electrophysiological Method for the Diagnosis of Extraforaminal Stenosis at L5–S1

Hiroshi Iwasaki,Munehito Yoshida,Hiroshi Yamada,Hiroshi Hashizume,Akihito Minamide,Yukihiro Nakagawa,Masaki Kawai,Shunji Tsutsui 대한척추외과학회 2014 Asian Spine Journal Vol.8 No.2

Study Design: A retrospective study. Purpose: To examine the effectiveness of using an electrodiagnostic technique as a new approach in the clinical diagnosis of extraforaminal stenosis at L5–S1. Overview of Literature: We introduced a new effective approach to the diagnosis of extraforaminal stenosis at the lumbosacral junction using the existing electrophysiological evaluation technique. Methods: A consecutive series of 124 patients with fifth lumbar radiculopathy were enrolled, comprising a group of 74 patients with spinal canal stenosis and a second group of 50 patients with extraforaminal stenosis at L5–S1. The technique involved inserting a pair of needle electrodes into the foraminal exit zone of the fifth lumbar spinal nerves, which were used to provide electrical stimulation. The compound muscle action potentials from each of the tibialis anterior muscles were recorded. Results: The distal motor latency (DML) of the potentials ranged from 11.2 to 24.6 milliseconds in patients with extraforaminal stenosis. In contrast, the DML in patients with spinal canal stenosis ranged from 10.0 to 17.2 milliseconds. After comparing the DML of each of the 2 groups and at the same time comparing the differences in DML between the affected and unaffected side of each patient, we concluded there were statistically significant differences (p <0.01) between the 2 groups. Using receiver operating characteristic curve analysis, the cutoff values were calculated to be 15.2 milliseconds and 1.1 milliseconds, respectively. Conclusions: This approach using a means of DML measurement enables us to identify and localize lesions, which offers an advantage in diagnosing extraforaminal stenosis at L5–S1.

Impact of Spinal Correction Surgeries with Osteotomy and Pelvic Fixation in Patients with Kyphosis Due to Osteoporotic Vertebral Fractures

Hasegawa Tomohiko,Ushirozako Hiroki,Yamato Yu,Yoshida Go,Yasuda Tatsuya,Banno Tomohiro,Arima Hideyuki,Oe Shin,Yamada Tomohiro,Ide Koichiro,Watanabe Yuh,Matsuyama Yukihiro 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.4

Study DesignCombination of retrospective and prospective study.PurposeWe aimed to compare the clinical outcomes between local fixation surgery and spinopelvic fixation surgery for the treatment of kyphosis secondary to osteoporotic vertebral fractures with spinopelvic malalignment.Overview of LiteratureThe clinical characteristics of patients with rigid kyphosis due to osteoporotic vertebral fracture differ from that of middle-aged patients with vertebral fractures in terms of bone fragility and presence of spinopelvic malalignment. Little is known about the surgical strategies for these deformities, most especially the extent of fusion of vertebra involved.MethodsWe analyzed 24 patients with vertebral osteotomy at the level of the fracture and spinal fixation without pelvic fixation (local group), and 22 patients with vertebral osteotomy and pelvic fixation (pelvic group). Radiographic parameters, the incidence of proximal junctional kyphosis (PJK), distal junctional kyphosis (DJK), rod fractures, and the Oswestry Disability Index (ODI) were compared between the two groups over a 2-year follow-up period.ResultsIn the pelvic group, postoperative spinopelvic parameters significantly improved, with the improvements maintained. No remarkable changes in spinopelvic parameters were seen in the local group. The mean ODI scores 2 years after surgery were 45.3 and 33.0 in the local and pelvic group, respectively (p-value <0.05). There was no significant difference in the incidence of PJK in the local and pelvic groups, but there was a higher rate of DJK (41.7%) in the local group. In contrast, rod fractures were more common in the pelvic group (45.5%). Patients with DJK had higher ODI scores 2 years after surgery (52.0 in DJK patients vs. 34.8 in non-DJK patients; p-value <0.05).ConclusionsFor patients with rigid kyphosis due to osteoporotic vertebral fractures, better spinopelvic alignment and health-related quality of life can be achieved through extensive corrective surgery with pelvic fixation.

Association between Pelvic Parameters and Vaginal Delivery

Yamada Tomohiro,Yamato Yu,Hasegawa Tomohiko,Yoshida Go,Yasuda Tatsuya,Banno Tomohiro,Arima Hideyuki,Oe Shin,Mihara Yuki,Ushirozako Hiroki,Ide Koichiro,Watanabe Yuh,Hosino Hironobu,Matsuyama Yukihiro 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.2

Study Design: Cross-sectional study. Purpose: To investigate the association between vaginal delivery and pelvic parameters and clarify the effect of parity on parameter fluctuations. Overview of Literature: During vaginal delivery, the sacroiliac joint widens and the sacrum nutates (nods). However, the association between these pelvic parameters and parity is unknown. Methods: As part of a 2016 health screening, 320 female volunteers underwent whole-spine radiographs. Age-matched healthy women were grouped according to the number of vaginal deliveries (0, 1–2, or ≥3). Demographic variables and spinopelvic parameters were compared among the three groups. Results: Of the 320 volunteers, 213 were enrolled (mean age, 71.1±7.2 years). The mean number of vaginal deliveries was 2.2. The average pelvic incidence (PI) was 55.6°±11.1° and was significantly higher in the 90 women with three or more vaginal deliveries than in the other two groups (p<0.001). The average sacral slope was 33.4°±11.1° and was significantly higher in the women with three or more vaginal deliveries than in the 18 who did not deliver vaginally (p<0.001). The 105 women with one or two vaginal deliveries had significantly higher PIs and sacral slopes than did those who did not deliver vaginally (p<0.001). Conclusions: This is the first study documenting an association between vaginal delivery and pelvic parameters. Bony birth canal realignment during vaginal delivery can affect postnatal PI. Our study helps in understanding the PI changes over a woman’s life span.