This paper described the comparison among 3 robotic systems which is now used in Japan in 2022. We started to use ExcelsiusGPS (Globus Medical) since December, 2021. The system is the most suitable for our operation theater. Safety, the cost-performance and education for young spine surgeons are the critical issues. We must consider the merit and demerit when we use robotic system.

Introduction: A loss of cervical lordosis or kyphotic change after posterior decompression surgery is one of the potential complications when treating patients with cervical spondylotic myelopathy (CSM). K-line in the neck-flexed position (flexion K-line) reflects anterior dynamic compression factors for the spinal cord. Posterior decompression can lead to poor neurological recovery for patients with CSM with flexion K-line (−) than those with flexion K-line (+).

In the present study, the authors aim to compare clinical outcomes and radiographic parameters including sagittal alignment or balance between Group A (flexion K-line [+] and neutral K-line [+]) and Group B (flexion K-line [−] and neutral K-line [+]).

Methods: A total of 42 consecutive patients were enrolled; the inclusion criteria were cases with CSM, posterior decompression surgery, ages 40 or over at the time of surgery, and minimum follow-up period of 6 months. The following radiographic parameters were measured: the minimum distance between K-line and vertebral body or osteophytes (KLBH: K-line brace height), local kyphosis angle, segmental range of motion (ROM), C2-C7 angle, C7 slope, and C2-C7 sagittal vertical axis (SVA). Clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) score for cervical myelopathy, JOA Cervical Myelopathy Evaluation Questionnaire, and Visual Analogue Scale. The patients were divided into Group A (n = 31) and Group B (n = 11).

Results: Preoperative KLBH in the flexion, neutral, and extension position and postoperative KLBH in the neutral position were significantly smaller in Group B than in Group A. A postoperative decrease of KLBH in the neutral position was significantly larger in Group B than in Group A. In two cases (4.8%), neutral K-line changed from (+) to (−) after surgery; both cases were in Group B. A postoperative decrease of C2-C7 angle was not significantly different between the two groups. C7 slope and C2-C7 SVA were similar between the two groups. The number of cases with preoperative focal kyphosis angle ≥10° and/or with segmental ROM ≥10° was significantly larger in Group B than in Group A. In addition, MRI findings and clinical outcomes were similar between the two groups.

Conclusions: In patients with CSM, neutral K-line can change from (+) to (−) after posterior decompression. Preoperative flexion K-line (−), focal kyphosis angle ≥10°, and segmental ROM ≥10° are potential risk factors for a loss of cervical lordosis or kyphotic change. With the above factors, additional measures including partial fusion or correction may be required to prevent a loss of cervical lordosis or kyphotic change.

Introduction: Recently, lateral lumbar interbody fusion (LLIF) has been widely used in correction surgery for adult spinal deformity (ASD), and its strong coronal correction force has the potential risk of coronal imbalance (CI) in the patients with residual lumbosacral fractional curve. Here, we investigated measures of postoperative CI and their effectiveness in circumferential minimally invasive surgery (CMIS) using LLIF and percutaneous pedicle screw (PPS) for ASD.

Methods: A total of 105 patients who underwent CMIS using LLIF and PPS at our institution since 2018 were included in this study. Patients were classified into two groups at the time of intraoperative first rod application-group CI (upper instrumented vertebra-central sacrum vertical line (UIV-CSVL) ≥10 mm) and group non CI (UIV-CSVL<10 mm). Pre- and postoperative spinopelvic parameters, L4 tilt, and C7-CSVL were compared. In the group CI, rod rotation technique (RR), S2 alar iliac screw (SAI) distraction (SD), and kickstand rod technique (KR) were performed as necessary, UIV-CSVL and its change were determined immediately after rod application and after various measures, and pre- and postoperative C7-CSVL were evaluated.

Results: Pre- and postoperative L4 tilt were significantly larger in group CI than group non CI. In group CI, improvement of UIV-CSVL was observed by various measures, and the amount of change in UIV-CSVL increased with the addition of measures, and the postoperative C7-CSVL was less than 10 mm in all measures.

Conclusions: Measures for CI and their effectiveness in CMIS for ASD were examined. By performing RR, SD, and KR sequentially, coronal balance could be corrected efficiently intraoperatively.

Introduction: The spinal instability neoplastic score (SINS) is a classification system used to diagnose neoplastic spinal instability. Several reports have also described its use as a screening tool to identify patients at risk of skeletal-related events. We investigated the efficacy of SINS to detect the risk of neurological deficit in patients with spinal metastases by assessing spinal metastatic instability before the onset of myelopathy.

Methods: We performed surgery on 81 patients with cervical or thoracic lesions classified as metastatic spine disease between 2004 and 2019. In this cohort, spinal instability was assessed in 29/81 patients before the occurrence of myelopathy. Spinal instability was evaluated by SINS with computed tomography (CT) performed within 6 months of the neurological deficit. We defined patients with a score of 7 or higher as at-risk patients.

Results: CT was performed at an average of 72 days before the onset of neurological deficits. The SINS were 2 no-metastases cases, 4 of less than 7 (stability), 15 of 7-12 (indeterminate instability), and 8 of 13-18 (instability). We were unable to detect 21% (6/29) patients at risk of SINS.

Conclusions: We may not be able to detect approximately 20% at-risk patients with neurological deficits by SINS before myelopathy presents.

Introduction: Several hospitals have introduced outpatient telephone consultations because of the COVID-19 pandemic. For the continuity and development of this approach, acquiring an understanding of the needs of patients and clarifying applicable cases are relevant objectives. This study aimed to clarify the characteristics of patients who did not prefer to continue telephone consultations.

Methods: A total of 293 patients with lumbar degenerative disc disease responded to a questionnaire regarding their preferences for future medical consultations (primary endpoints of the study). Participants selected one from the following responses: "always by phone," "sometimes by phone," "by phone in case of emergency," and "always face-to-face." We collected information on patient demographics, medical treatment, and symptom history using medical records as secondary endpoints. In addition, we performed a logistic regression analysis to examine the characteristics of patients who expressed a preference for care that was "always face-to-face."

Results: The average age of the patients was 72 years. They had received an average of 1.5 telephone consultations, and 4% of these patients chose "always by phone" as their preference for future medical consultations. Further, 29% chose "sometimes by phone," 28% chose "by phone in case of emergency," and 29% chose "always face-to-face." A multivariate analysis revealed that patients who preferred face-to-face consultations were more likely to be in their 70s (odds ratio: 2.30). Furthermore, these patients scored higher on the numeric rating scale (NRS) for back pain (1.15). In this group, there were fewer patients with J1 daily living skills (0.40) compared with other respondents.

Conclusions: Patients in their 70s, those with severe back pain, and those who were limited in their activities of daily living tended to prefer face-to-face medical consultations. Many of these patients prefer to consult with their doctors about their pain face-to-face rather than by phone. Moreover, several might prefer to receive a palpation or injection.

Introduction: The kickstand rod technique (KRT) is developed by Lenke et al. to correct residual intraoperative and postoperative coronal malalignment (CM) in thoracic-iliac corrective surgery. The iliac bone on the shift side is arranged through the usual median longitudinal skin incision and another iliac screw is added, and a closed-closed domino connector is placed at the thoracolumbar transition of the main rod on the shift side. A kickstand rod is placed between the added iliac screw and the domino connector, the set screws securing the two main rods are loosened except at the sacral and iliac regions, and a distraction force to correct is applied between the domino corrector and the distal rod grippers. Regarding CM after adult spinal deformity correction surgery, it is reported that CM remains in 60% and occurs iatrogenically in 9% of the cases postop. Insufficient correction of the lumbosacral fractional curve can result in oblique takeoff and cause CM. Here, we describe 3 cases of intraoperative additional correction of lumbar degenerative scoliosis with KRT for CM that remains after the usual correction procedure.

Case Report: The ages at surgery were 68, 73, and 74 years, and the preoperative distance between the C7 plumbline and center sacral vertical line (C7PL-CSVL) was 20, 65, and 33 mm. In each case, lateral interbody fusion (LIF) (L2/3-4/5, L2/3-4/5, L1/2-5/6) was performed anteriorly, and posterior fixation (9th thoracic vertebrae-ilium) was performed in two stages. Posterior lumbar interbody fusion was performed on the lower lumbar-sacral vertebrae that did not undergo LIF, and the fractional curve was corrected. Since CM remained in the intraoperative X-ray after the usual correction procedure, the additional correction was performed with KRT. The C7PL-CSVL was 13, 11, and 18 mm in the postoperative first standing position X-ray.

Conclusions: We experienced three cases of intraoperative additional correction with KRT for CM that remains after the usual correction procedure. KRT is a simple and useful procedure that can be the standard for spine surgeons.

Introduction: We successfully performed the surgical resection of lumbosacral pseudoarticulation using intraoperative computed tomography-based navigation system in 2 cases with Bertolotti's syndrome.

Case Report: Case 1 was 15-year-old girl. After pseudoarthrectomy, the VAS score of low back pain improved from VAS 90 to 30 mm. Case 2 was 21-year-old woman, who had a persistent low back pain (VAS 40 mm) even after the microscopic pseudoarthrectomy probably due to incomplete pseudoarthrectomy. We performed navigation-assisted resection of the remaining anomalous transverse process in the second surgery, and her symptom improved (VAS 40 to 20 mm).

Conclusions: The resection of anomalous transverse processes is sometimes difficult because of the anomalous feature and poor visibility. Navigation-guided approach facilitated complete resection.