With the emergence of big data and more personalized approaches to spine care and predictive modeling, data science and deep analytics are taking center-stage. Although current techniques in machine learning and artificial intelligence have gained attention, their applications remain limited by their reliance on traditional analytic platforms. Quantum computing has the ability to circumvent such constraints by attending to the various complexities of big data while minimizing space and time dimensions within computational algorithms. In doing so, quantum computing may one day address research and clinical objectives that currently cannot be tackled. Understanding quantum computing and its potential to improve patient management and outcomes is therefore imperative to drive further advancements in the spine field for the next several decades.

Background: A thoracolumbar burst fracture (BF) is a severe type of compression fracture, which is the most common type of traumatic spine fractures. Generally, surgery is the preferred treatment, but whether the optimal approach is either an anterior or a posterior approach remains unclear. This study aims to determine whether either method provides an advantage.

Methods: Following PRISMA guidelines, a systematic review was conducted, identifying studies comparing anterior versus posterior surgical approaches in patients with thoracolumbar BFs. Data were analyzed using Review Manager 5.3. Seven studies were included.

Results: An operative time of 87.97 min (53.91, 122.03; p<0.0001) and blood loss of 497.04 mL (281.8, 712.28; p<0.0001) were lower in the posterior approach. Length of hospital stay, complications, reintervention rate, neurological outcomes, postoperative kyphotic angle, and costs were similar between both groups.

Conclusions: Surgical intervention is usually selected to rehabilitate patients with BFs. The data obtained from this study suggest that a posterior approach represents a viable alternative to an anterior approach, with various advantages such as a shorter operative time and decreased bleeding.

Introduction: In the early phase of the coronavirus disease 2019 (COVID-19) pandemic, the importance of triaging surgeries was suggested to reduce burdens on the existing health system and maintaining service. The governor declared a state of emergency and requested that residents avoid going out unnecessarily (semi-lockdown) for the entire prefecture including our medical region from February 28 until May 25, 2020. However, for several spine patients, a significant delay in care may result in the progression of extremity weakness and pain. This study aimed to investigate trends of spine surgeries during the first COVID-19 semi-lockdown in the nonepidemic region in Japan.

Methods: Spine surgeries performed in our institution from February 28 until May 25 between 2017 and 2020 were retrospectively reviewed and analyzed. We compared the number of spine surgeries and types of surgical spine pathologies between 2017 and 2019: previous years and 2020: a COVID-19 year.

Results: The mean number of spine surgeries performed in previous years was 121 cases, and the number of spine surgeries performed in a COVID-19 year was 109 cases. The percentage of urgent surgeries was 19.6% in previous years versus 37.6% in a COVID-19 year; the difference was statistically significant (P<0.05). Among the urgent surgical spine pathologies, the prevalence of cauda equina or severe nerve root compression leading to progressive neurological deterioration or intractable pain was 20.2% in a COVID-19 year, which was significantly higher than 12.4% in previous years (P<0.05).

Conclusions: The first COVID-19 semi-lockdown in Japan led to a decrease in elective cases and an increase in urgent cases and might affect progressive neurological deterioration for some spine patients even in a nonepidemic region.

Introduction: The present study aimed to understand the characteristics of adjacent segment stenosis post-surgery by examining the status of adjacent segment stenosis in patients with long-term follow-up after muscle-preserving selective laminectomy (SL).

Methods: We examined 43 patients who underwent muscle-preserving SL at a single academic institution and were followed up for >10 years. The C2-C7 angle, C2-C7 sagittal vertical axis, range of motion, and C7 slope were measured using an X-ray lateral view. The anterior-posterior diameter of the spinal cord (AP of SC) and anterior-posterior diameter of the dural tube (AP of dura) at adjacent segment were measured using magnetic resonance imaging T2-weighted sagittal section. Residual space for the spinal cord at the adjacent segment (SAC) was calculated as the difference between AP of SC and AP of dura.

Results: Four cases had cephalad adjacent segment stenosis at the last follow-up (upper stenosis (US) group), 9 cases had caudal adjacent segment stenosis ( lower stenosis (LS) group), and 30 cases had no stenosis (none (N) group). AP of SC, AP of dura, and SAC at the upper adjacent segment were significantly lower in the US group. AP of dura and SAC at the lower adjacent segment were significantly lower in the LS group. Multivariate logistic regression analysis revealed that the small AP of dura in the upper adjacent segment and small SAC in the lower adjacent segment were risk factors for developing a new stenosis.

Conclusions: Decompression should be considered beforehand in adjacent segments with small AP of SC and small AP of dura when performing cervical decompression.

Introduction: Cervical isometric muscle strengthening and cervical range of motion (ROM) training are recommended after laminoplasty (LP). However, their preventive effects on axial pain are unclear. We examined whether neck extension muscle strengthening and cervical ROM training from the early postoperative period effectively suppress postoperative axial pain.

Methods: Sixty-one patients undergoing a muscle-preserving LP attached to C2 and C7 for cervical spondylotic myelopathy or ossification of the posterior longitudinal ligament were randomly allocated to the cervical exercise (33 patients) or nonexercize (28 patients) groups. Postoperative cervical collars were not worn in any cases. The cervical exercise group underwent neck extension isometric muscle strengthening and cervical ROM exercises for 3 months starting on postoperative day 2. Changes in axial pain (visual analog scale [VAS]) from baseline at 2 weeks and 3 months after surgery were evaluated as the primary outcome. Cervical muscle strength, cervical ROM, and Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) scores were evaluated as secondary outcomes.

Results: Axial pain was significantly exacerbated at 2 weeks after LP compared with before surgery, and then, a significant improvement was observed at 3 months after surgery. No significant interaction was observed between the intervention and nonintervention groups. There was no difference in secondary outcomes between groups. The change in the VAS of axial pain from before surgery to 3 months after surgery showed a greater decreased neck extension muscle strength resulting in severer axial pain.

Conclusions: Cervical muscle strengthening and cervical ROM exercise from the early postoperative period did not relieve axial pain at 2 weeks and 3 months after a muscle-preserving LP attached to C2 and C7. No significant difference in neck extension muscle and cervical movement was observed between the intervention and nonintervention groups. Therefore, a muscle-preserving LP attached to C2 and C7 is a good strategy to prevent axial pain in the early postoperative period.

Clinical Trials Registration Number: UMIN000040692

Introduction: Although strict compliance with brace wearing is important for patients with scoliosis, no study has analyzed the most ideal conditions for temperature logger accuracy. We evaluated the optimal brace position and threshold temperature for the logger and determined the reliability of its measurements in patients with scoliosis.

Methods: Five temperature loggers were embedded into holes generated at five different brace positions (right scapula, right chest, left chest, lumbar, and abdomen) within the brace. We compared measurement errors at each position using different threshold temperatures to determine the ideal anatomical position and threshold temperature. Under the ideal conditions determined, we calculated the reliability of the temperature logger readings in three healthy participants.

Results: Measurement errors (i.e., differences between the actual and logger-recorded brace wearing times) were the lowest at the 28°C and 30°C threshold temperatures when the logger was positioned at the left chest and at 30°C at the abdomen. Among these three temperature/position combinations, we considered the abdomen to be the least affected by the shape of the brace; thus, the placement of the temperature logger at the abdomen using a threshold temperature of 30°C was the most ideal condition.

Conclusions: The placement of the temperature logger at the abdomen using a threshold temperature of 30°C was the most ideal condition, with the reliability of the logger being 97.9%±0.9%. This information might be useful for scoliosis management teams, and this temperature logger provides a valuable clinical tool.

Introduction: The purpose of this study was to assess radiological features and clinical scores of osteoporotic vertebral fracture (OVF) accompanied by spinous process fracture (SPF).

Methods: We included painful patients with single-level OVF with intravertebral cleft. SPF was detected using magnetic resonance imaging (MRI) and/or computed tomography (CT). The plain radiographs of the vertebral fractures were evaluated based on the wedging angle of the fractured vertebrae and vertebral instability. We investigated the clinical parameters of age, gender, visual analog scale (VAS) score for low back pain (LBP), Oswestry Disability Index (ODI), and the period from the onset of acute fracture.

Results: MRI and/or CT indicated among 195 patients of OVF with LBP, 41 patients (20.5%) had SPFs. SPFs were observed one level above the fractured vertebral body in 35 patients (85.4%) and at the same level as the fractured vertebral body in 6 patients (14.6%). The prevalence of vertebral fracture of thoracic spine in the SPF-positive group was significantly greater than that in the SPF-negative group. There were no significant differences in age, gender, VAS, ODI, the time period from the onset of acute LBP, wedging angle, and vertebral instability between the presence or absence of SPFs.

Conclusions: SPFs occurred in 20.5% of patients with OVF and LBP. In addition, SPFs often occurred one level above the fractured vertebra, and SPFs with OVF tended to be located in the thoracic spine.

Introduction: Osteoporotic vertebral compression fracture (OVCF) in the elderly is a major public health concern. This retrospective case-control study aimed to determine the difference in interobserver reliability between radiography, magnetic resonance imaging (MRI), and computed tomography (CT), respectively, and whether CT radiological findings can predict prolonged back pain at 2 weeks after OVCFs.

Methods: Patients were divided into the prolonged back pain group or the recovered back pain group depending on the numerical rating scale at 2 weeks after admission. Radiography, MRI, and CT images were classified on the basis of conventions described by previous classifications. Interobserver reliability was calculated on images rated by two board-certified spine surgeons. Multivariate logistic regression models were used to evaluate whether the presence or absence of anterior wall injury, endplate deficit, posterior wall injury, lateral wall injury, or intervertebral disc deficit on CT was predictive of prolonged back pain.

Results: Of the 130 patients, 89 cases (68.5%) involved prolonged back pain at 2 weeks after admission. Neither average age (79.8 vs. 80.1 years, respectively) nor duration to initial consultation (9.4 vs. 6.4 days, respectively) differed significantly between the prolonged and recovered back pain groups. Interobserver reliability was 0.51, 0.77 (0.67-0.86), and 0.82 (0.72-0.92) for radiography, MRI, and CT, respectively.

After adjusting for confounding factors such as age, sex, duration to initial consultation, and extent of OVCF, the multivariate analysis showed that the presence of endplate deficit and posterior wall injury was a significant predictive factor for prolonged back pain (odds ratio [OR] 8.5, area under the curve (AUC); 0.79 and OR 2.5, AUC 0.72), respectively.

Conclusions: Good reliability assessments of CT-based evaluations were noted. After a detailed novel CT evaluation at initial presentation, the presence of an endplate deficit and posterior wall injury was the significant risk factor for prolonged back pain at 2 weeks after an OVCF.

Introduction: The use of the antifibrinolytic agent tranexamic acid has positive effects on bleeding control, but our knowledge is still limited regarding how fibrinolysis suppression changes the process of bone formation and the quality of bone. Because of the several side effects of systemic tranexamic acid, topical usage has been established in several procedures. This study aimed to investigate the effect of local tranexamic acid on vertebral fusion by using macroscopic, radiologic, and microscopic techniques. We also attempted to determine the safe dose range in case some doses had negative effects on fusion.

Methods: Twenty-eight Wistar albino rats underwent intertransverse fusion. All rats were randomized into four groups: groups treated with local tranexamic acid doses of 1 mg/kg (D1), 10 mg/kg (D10), and 100 mg/kg (D100) and the control group with no drug (D0). At the end of the eighth week, all rats were sacrificed for evaluation in terms of palpation, mammography, and histopathologic analysis.

Results: The manual palpation results presented with lower fusion rates in D10 and D100 groups than in the control group. Radiological examination results were significantly higher in the control group. The histopathologic examination revealed no significant differences between groups in the percent of new bone formation.

Conclusions: Our results showed that local administration of tranexamic acid reduced the quality and stability of fusion without a delay in bone formation. However, doses of 1 mg/kg did not reduce the stability in the palpation test. Our findings suggest that 1 mg/kg dose is a critical threshold above which tranexamic acid reduced the bone healing process of fusion and that surgeons should consider the doses of local tranexamic acid during surgery.

Introduction: Balloon kyphoplasty (BKP) is a minimally invasive surgical approach for the treatment of osteoporotic vertebral fractures (OVF). Some risks have been reported after treatment with BKP; therefore, it is necessary to determine when BKP does not work. Thus, in this study, we aim to clarify the radiographic predictors of secondary vertebral fractures and cement loosening after BKP for OVF.

Methods: This study enrolled patients with single-level OVF at the thoracolumbar junction (T11-L2) who underwent BKP for the first time between January 2011 and March 2014. The clinical outcomes were evaluated using the visual analog scale (VAS) and a modified Oswestry Disability Index (ODI) at 1 week and 1, 3, 6, and 12 months after surgery. Radiographic assessments were performed preoperatively and within 1 year after BKP using plain radiography and computed tomography.

Results: The 85 patients who met the inclusion criteria underwent BKP. The average age of participants (21 men, 64 women) was 77.8 years (range, 57-92 years). Postoperative VAS and ODI scores were all significantly better than preoperative scores. Polymethyl methacrylate (PMMA) -cement leakage was observed in 18 patients (21.2%) but was asymptomatic in all cases. Secondary vertebral fractures were detected in 20 patients (23.5%), including adjacent levels in 15 patients (17.6%) and non-adjacent levels in 5 patients (5.9%). Rostral bridging osteophyte formation was found to be significantly associated with the occurrence of adjacent vertebral fractures (odds ratio 12.746; p=0.010). PMMA-cement loosening was observed in three patients (3.5%). A high prevalence (100%) of bridging osteophytes, vacuum clefts, and spinous process fractures was observed in patients with PMMA-cement loosening. PMMA-cement loosening was found in 3 out of 10 patients with all three of these factors.

Conclusions: Rostral bridging osteophyte formation was determined to be a risk factor for both adjacent vertebral fractures and PMMA-cement loosening.

Level of Evidence: 3

Introduction: For the aging population, surgery for lumbar spinal canal stenosis (LSCS) requires minimally invasive procedures. Recently, trans-sacral epiduroscopic laser decompression for lumbar disc herniation has been reported with good results. In this study, we devised a new method to perform trans-sacral epiduroscopic laser ablation of the ligamentum flavum (LF), known to be the major cause of LSCS. Using a live pig, this study aims to evaluate the efficacy, safety, and drawbacks of this procedure.

Methods: Using an epiduroscope, we observed intra-spinal canal structures and then examined the feasibility and problems of a decompression procedure to ablate the LF using holmium:YAG (Ho:YAG) laser. The pig was observed for behavioral changes and neurological deficits after the procedure. Histological analysis was performed to evaluate the amount of tissue ablation and damage to surrounding tissues.

Results: Although it was possible to partially ablate the LF using the Ho:YAG laser under epiduroscopy, it was difficult to maintain a clear field of view, and freely decompressing the target lesion has been a challenge. After the first two experiments, the pig neither showed abnormal behavior nor any signs of pain or paresis. However, in the third experiment, the pig died during the operation. On autopsy, no thermal or mechanical injury was noted around the ablated site, including the dura mater and nerve root. Histological analysis showed that the LF and lamina were deeply ablated as the laser power increased, and no damage was noted on surrounding tissues beyond a depth of 500 μm.

Conclusions: Although Ho:YAG laser could ablate the ligamentum and bone tissues without causing damage to surrounding tissues, it was difficult to completely decompress the LF under epiduroscopy. This method is a potentially highly invasive procedure that requires caution in its clinical application and needs further improvement in terms of the instruments and techniques used.

Introduction: Atlantoaxial dislocation (AAD) is a complicated and challenging deformity with severe morbidities. Irreducible AAD with C1/2 bony fusion requires anterior (transoral or transnasal) odontoidectomy to decompress spinal cord or medulla, which is highly demanding technique that is risky for comorbidities. Here, we report our application of modified Goel's technique to reduce AAD with bony fusion through single-stage posterior approach surgery.

Technical Note: Our technique that can reduce AAD with bony fusion through single-stage posterior approach surgery is reported. Joint release, distraction, cage implantation, and atlantoaxial or occipitocervical fixation can successfully manage AAD with C1/2 bony fusion. Key points for the technique include pinpointing original joint space, thorough release of bony fusion, stepwise distraction, and cage implantation with autograft.

Conclusions: Joint release, distraction, cage implantation, and atlantoaxial or occipitocervical fixation can successfully manage bony irreducible AAD. This technique provided an option for bony fused AAD and improved safety and efficacy of its management.