Preoperative Less Right Shoulder Elevation Had a Higher Risk of Postoperative Shoulder Imbalance When Main Thoracic Curve Shows Higher Correction Regardless of the Upper Instrumented Vertebra Level for Patients with Adolescent Idiopathic Scoliosis Lenke

Banno Tomohiro,Yamato Yu,Hasegawa Tomohiko,Yoshida Go,Arima Hideyuki,Oe Shin,Mihara Yuki,Ide Koichiro,Watanabe Yuh,Kurosu Kenta,Nakai Keiichi,Matsuyama Yukihiro 대한척추외과학회 2023 Asian Spine Journal Vol.17 No.1

Study Design: This is a retrospective study.Purpose: This study aimed to investigate the incidence of and risk factors for postoperative shoulder imbalance (PSI) in patients with Lenke type 1.Overview of Literature: PSI is a complication resulting in poor self-image and satisfaction in adolescent idiopathic scoliosis (AIS) patients.Methods: We examined the data of AIS patients with Lenke type 1 curves who underwent posterior fusion surgery in a retrospective manner. PSI was defined as a 2-year postoperative absolute radiographic shoulder height (RSH) of ≥2 cm. Patients were divided into two groups based on the presence of PSI and the level of their upper instrumented vertebra (UIV) (UIV at T2 or T3 [U-UIV] or UIV below T3 [L-UIV]). The radiographic parameters and clinical outcomes were compared, and the cutoff values of risk factors were identified by multivariate analysis.Results: Of 104 patients, 21 (20.2%) had left shoulder elevation PSI. The PSI group had a significantly greater preoperative RSH (−5.1 mm vs. −14.3 mm) and main thoracic (MT) curve correction rate (77.3% vs. 69.1%) than the non-PSI group. The PSI incidence did not differ between the U-UIV and L-UIV groups. Multivariate analysis identified preoperative RSH and the MT curve correction rate as independent risk factors for PSI. The receiver operating characteristic curve analysis identified the preoperative RSH cutoff value as −6.5 mm and MT curve correction rate cutoff value as 76.9%.Conclusions: Even in AIS patients with Lenke type 1 curves, the incidence of PSI was relatively high (20.2%). Patients with preoperative lower right shoulder elevation (i.e., RSH >−6.5 mm) had a higher risk of PSI regardless of UIV level when the MT curve showed a higher correction rate (i.e., correction rate >76.9%).

Multi-Rod Constructs Can Increase the Incidence of Iliac Screw Loosening after Surgery for Adult Spinal Deformity

Tomohiro Banno,Tomohiko Hasegawa,Yu Yamato,Daisuke Togawa,Go Yoshida,Sho Kobayashi,Tatsuya Yasuda,Hideyuki Arima,Shin Oe,Yuki Mihara,Hiroki Ushirozako,Yukihiro Matsuyama 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.3

Study Design: A retrospective study. Purpose: To investigate the incidence of iliac screw loosening with a two-rod vs. multi-rod construct and the effect on clinical and radiographic outcomes after surgery for adult spinal deformity (ASD). Overview of Literature: Multi-rod construct is useful for preventing rod fracture in ASD surgery. However, limited information is available regarding the incidence of iliac screw loosening after corrective fusion surgery using a multi-rod construct. Methods: Total 106 patients with ASD (24 men and 82 women; mean age, 68 years) who underwent corrective fusion surgery using bilateral iliac screws and were followed up for at least 1 year were reviewed. The following variables were compared between patients who underwent surgery with a two-rod and multi-rod construct: age, sex, bone mineral density (BMD), fusion level, high-grade osteotomy, L5/S interbody fusion, screw loosening (upper instrumented vertebra [UIV], S1, and iliac), rod fracture, proximal junctional kyphosis, spinopelvic parameters, and Oswestry Disability Index (ODI) score. We also compared patients with and without iliac screw loosening in the multi-rod construct group. Results: Of the 106 patients, 55 underwent surgery with a conventional two-rod construct and 51 with a multi-rod construct (three rods in 16, four rods in 35). Iliac and UIV screw loosening was observed in 24 patients (21%) and 35 patients (33%), respectively. The multi-rod group showed significantly higher incidence of iliac and UIV screw loosening and lower incidence of rod fracture. Patients with iliac screw loosening had a lower BMD than those without screw loosening; however, no significant differences were observed in the spinopelvic parameters or the ODI score. Conclusions: The use of multi-rod constructs led to a higher incidence of junctional screw loosening than the use of conventional two-rod constructs, especially in patients with osteoporosis. Iliac screw loosening did not affect sagittal alignment or clinical outcome in the short term.

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.

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.

Change in Line of Sight after Corrective Surgery of Adult Spinal Deformity Patients: A 2-Year Follow-up

Magcalas Ken Jeffrey,Oe Shin,Yamato Yu,Hasegawa Tomohiko,Yoshida Go,Banno Tomohiro,Arima Hideyuki,Mihara Yuki,Ushirozako Hiroki,Yamada Tomohiro,Ide Koichiro,Watanabe Yuh,Matsuyama Yukihiro 대한척추외과학회 2023 Asian Spine Journal Vol.17 No.2

Study Design: Cohort study.Purpose: There is currently no published study that focuses on the spinal corrective surgery effects with cranial parameters in adult spinal deformity (ASD) patients. It is an important factor to measure since it plays a critical role in maintaining the line of sight. The objective is to determine the change in cranial parameters using the slope of McGregor’s line (McGS) after ASD surgery after 2 years of follow-up.Overview of Literature: A study concluded that cervical spine alignment (C2–C7 lordosis) is strongly affected by thoracic kyphosis (TK). Another study showed that patients with ascending gaze had significantly more thoracolumbar malalignment.Methods: This retrospective study includes 295 corrective surgery patients with ASD. Subjects were divided into two groups after propensity age matching analysis: cranial malalignment (McGS <−8 or >13) and normal cranial alignment (−8≤ McGS ≤13). Lumbar lordosis (LL), pelvic tilt (PT), TK, cervical lordosis (CL), and sagittal vertical axis (SVA) were evaluated between the two groups.Results: SVA (95–56 mm) and PT (34°–25°) decreased and LL (19°–41°) increased 2 years after surgery (p <0.05), but McGS (−1.1° to −0.5°) and CL (21°–19°) did not change. Conversely, in the group with cranial malalignment, SVA (120–64 mm), PT (35°–26°), and LL (12°–41°) showed similar results to the normal cranial parameter group 2 years after surgery, but in contrast, McGS (−13° to −2°) and CL (24°–18°) improved significantly.Conclusions: Severe ASD adversely affects to maintain horizontal gaze but can be improved by spinal corrective surgery.

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.

Relationship between Knee Osteoarthritis and Spinopelvic Sagittal Alignment in Volunteers over 50 Years of Age

Yasuda Tatsuya,Togawa Daisuke,Hasegawa Tomohiko,Yamato Yu,Kobayashi Sho,Yoshida Go,Banno Tomohiro,Arima Hideyuki,Oe Shin,Hoshino Hironobu,Koyama Hiroshi,Hanada Mitsuru,Imada Takayuki,Matsuyama Yukihir 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.4

Study Design: Large cohort study of volunteers.Purpose: The purpose of this study was to investigate the relationship between the severity of knee osteoarthritis, assessed using the Kellgren-Lawrence (KL) grading scale, and spinopelvic sagittal alignment in older adult volunteers.Overview of Literature: The relationship between spinopelvic alignment in the sagittal plane and knee osteoarthritis in the coronal plane is unclear.Methods: Volunteers over 50 years of age underwent radiographic analysis. Radiographic parameters including pelvic tilt (PT), pelvic incidence (PI), lumbar lordosis (LL), thoracic kyphosis, and sagittal vertical axis (SVA) were measured. The the three Scoliosis Research Society-Schwab sagittal modifiers (PT, SVA, I–LL) were categorized and the KL grade was assessed. Differences in spinopelvic parameters and Oswestry Disability Index (ODI) scores among KL grades were evaluated.Results: A total of 396 volunteers (160 men, 236 women; mean age, 74.4 years) were analyzed. PI–LL and PT in KL4 were significantly higher compared to that in the other KL grades. However, there were no significant group differences in SVA. In women, but not in men, higher frequencies of the worst modifier grade (++) were observed for PI–LL and PT in the KL3 and KL4 groups compared to those for the other KL grades. In women, the ODI score in KL4 was worse compared to that in the other KL grades.Conclusions: Individuals over 50 years of age with severe knee osteoarthritis had poor lumbo-pelvic sagittal alignment. Moreover, the progression severity of knee osteoarthritis had more impact onstronger relationship with lumbo-pelvic malalignment and disability-related low back pain in women than in men.

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.

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.

Relationship between Spinal Hemangioblastoma Location and Age

Tatsuya Yasuda,Tomohiko Hasegawa,Yu Yamato,Sho Kobayashi,Daisuke Togawa,Tomohiro Banno,Hideyuki Arima,Shin Oe,Yukihiro Matsuyama 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.2

Study Design: Retrospective case series. Purpose: To investigate the relationship between tumor location and clinical characteristics. Overview of Literature: Hemangioblastoma is a rare disease that develops in the central nervous system. Magnetic resonance imaging (MRI) is useful to evaluate hemangioblastomas. Hemangioblastoma’s location is designated as intramedullary, intramedullary+extramedullary, or extramedullary by MRI. Methods: We analyzed 11 patients who underwent surgery for spinal hemangioblastoma. Using T1 contrast axial MRI data, the cases were divided into three groups (intramedullary, intramedullary+extramedullary, and extramedullary). Patient demographics, MRI findings, and preoperative neurological status were analyzed and compared for each group. Results: The average age of patients with intramedullary, intramedullary+extramedullary, and extramedullary hemangioblastoma was 34.0, 64.4, and 67.5 years, respectively. Patients in the intramedullary hemangioblastoma group were younger than the other groups. Extramedullary cases had a smaller syrinx compared to the other groups. Conclusions: Age may play an important role in the hemangioblastoma tumor location and the subsequent diagnosis by an MRI.