Severe Spinal Deformity Research Articles

Preoperative halo-gravity traction combined with one-stage posterior spinal fusion surgery following for severe rigid scoliosis with pulmonary dysfunction: a cohort study

BackgroundTo assess the efficacy of preoperative halo-gravity traction (HGT) in treating severe spinal deformities, evaluating radiological outcomes, pulmonary function, and nutritional status.MethodsThis study retrospectively included 33 patients with severe spinal deformity who were admitted to our department from April 2018 to January 2022. All the patients underwent HGT prior to the posterior spinal fusion corrective surgery, with no patients having undergone anterior or posterior release procedures. The correction of deformity, pulmonary function tests (PFTs), and nutritional status data were collected and analyzed before and after HGT.ResultsA total of 33 patients (9 males, 24 females) were finally included in this study with an average age of 17.79 ± 7.96 (range 12–29) years. Among them, 20 patients were aged ≤ 16 years. The traction weight started from 1.5 kg and raised to 45.2 ± 13.2% of body weight on average progressively, with the average traction duration of 129 ± 63 days. After traction, the main curve was corrected from an average of 120.66 ± 3.89° to 94.88 ± 3.35°, and to 52.33 ± 22.36° (53%) after surgery(P < 0.05). PFTs also showed a significant increase in FVC%, FEV1%, and MEF% after traction [43.46 ± 14.76% vs. 47.33 ± 16.04%, 41.87 ± 13.68% vs. 45.19 ± 15.57%, and 40.44 ± 15.87% vs. 45.24 ± 17.91%, p < 0.05]. Total protein, albumin, and BMI were used as indicators of nutritional status. TP and albumin were significantly improved after traction, from 67.24 ± 5.43 g/L to 70.68 ± 6.98 g/L and 42.40 ± 3.44 g/L 45.72 ± 5.23 g/L, respectively(P < 0.05). No significant difference was found in deformity correction and lung function improvement between patients with traction for more or less than three months (p > 0.05). Two patients developed transient brachial plexus palsy during traction.ConclusionsHalo-gravity traction can partially correct spinal deformity, enhance pulmonary function. And HGT has been shown to facilitate an improved nutritional status in these patients. It could be used as a preoperative adjuvant treatment for severe spinal deformity. However, according to the study, a traction period longer than three months may not be necessary.

Transverse interlaminar ultrasound-guided C1-C2 puncture for the intrathecal administration of nusinersen in patients with spinal muscular atrophy.

Severe spinal deformities and previous spinal orthopedic instrumentation may result in substantial technical challenges for nusinersen delivery through lumbar puncture in patients with spinal muscular atrophy (SMA). The aim of this paper was to review our experience with ultrasound-guided cervical puncture as an alternative approach for the intrathecal administration of nusinersen. This was a retrospective medical record review of transverse interlaminar ultrasound-guided C1-C2 puncture for nusinersen delivery in SMA patients. The details of puncture, complications, and success rate of the procedure were summarized. There were four patients who received a total of 13 cervical punctures for nusinersen delivery. All procedures were technically successful with no major complications. Full doses of nusinersen were delivered intrathecally. Transverse interlaminar ultrasound-guided C1-C2 puncture is an alternative approach for administering nusinersen if lumbar puncture fails. The success of the technique requires a thorough preprocedural evaluation of cervical spine imaging, sound knowledge of the cervical sonoanatomy and careful manipulation of the needle.

Outcomes of Traditional Dual Growing Rods With Apical Control Techniques for the Treatment of Early-Onset Scoliosis: Comparison With Patients Treated With Traditional Dual Growing Rods Only With a Minimum 2-Year Follow-up After Graduation.

Correction with traditional dual growing rods (TDGR) might not be sufficient for severe and rigid spinal deformity. TDGR combines with apical control techniques (ACT) could theoretically improve curve correction and decrease the incidence of mechanical complications. However, long-term results for TDGR with ACT are limited. The aim of this study was to retrospectively review and compare the outcomes of patients who graduated from TDGR with or without ACT. Patients who were treated by TDGR with or without ACT with a minimum 2-year follow-up after graduation were enrolled. According to the intervention for the apex, patients were further divided into the TDGR group, the TDGR + apical control pedicle screws group (without apical fusion), and the TDGR + hybrid technique group. Clinical outcomes, radiological parameters, pulmonary function, and complications were compared among the 3 groups. A total of 76 patients (51 patients in the TDGR group, 10 patients in the apical control pedicle screws group, and 15 patients in the hybrid technique group) were enrolled. Compared with TDGR, TDGR + ACT achieved better main curve correction, better control of apical vertebral translation and rotation, and lower incidence of complications and revision surgery (P < .05) while maintaining development of the spine and chest. Although the difference was not significant, patients in the TDGR + ACT group had better pulmonary function at the last follow-up (P > .05). The percentage of patients receiving final fusion in the TDGR + ACT group was significantly lower than that in the TDGR group (P < .05). Compared with TDGR, TDGR + ACT can achieve better curve correction and apical control and comparable clinical outcomes while maintaining the growth of the spine and chest. Patients may derive more benefits from treatment with TDGR + ACT, including a lower incidence of mechanical complications and revision surgery, better pulmonary function, and the avoidance of final fusion.

Surgical Treatment Strategies for Severe and Neglected Spinal Deformities in Children and Adolescents without the Use of Radical Three-Column Osteotomies.

Background: Severe spinal deformity manifests as a pronounced deviation from the normal curvature of the spine in the frontal, sagittal, and horizontal planes, where the coronal plane curvature exceeds 90 degrees and may coincide with hyperkyphotic deformity. The most severe deformities exhibit rigidity, with flexibility below 30%. If left untreated or improperly treated, these deformities can result in serious complications associated with progression of the curvature. A combination of surgical techniques is frequently employed to attain optimal outcomes and minimize the risk of complications. The overall medical condition of the patient, their capacity to endure extensive procedures, the expertise of the surgeon, and the resources available all play significant roles in determining the course of management. A systematic and thorough review of the relevant literature was conducted utilizing a variety of electronic databases. The primary objective of this study was to scrutinize the surgical techniques commonly employed in complex spine surgeries for the management of severe scoliosis without resection vertebral body techniques, with higher potential risk of major complications, including permanent neurological deficit. Conclusions: Halo-gravity traction, halo femoral traction, and all techniques for releases of the spine (anterior, posterior, or combine), as well as thoracoplasty, have demonstrated significant effectiveness in managing severe and rigid idiopathic scoliosis. The combination of several of these methods can lead to optimal alignment correction without the need to perform high-risk techniques involving three-column osteotomies. Surgeons must customize the indications based on factors such as available resources, characteristics of the deformity, and the patient's individual profile. Surgical correction of severe scoliosis without vertebral body resection surgeries decreases the potential risks related to neurological and pulmonary complications while providing significant clinical improvement outcomes. The powerful Ponte osteotomy is indicated for severe scoliosis, curves with poor flexibility, for better restoration of hypokyphosis, and decrease of hyperkyphosis. These corrective techniques combined with HGT or temporary internal distraction rods are recommended as viable options for managing individuals with severe rigid spine deformity characteristics. Therefore, they also should be considered and performed by a proficient surgical team. The presence of neuromonitoring is crucial throughout these procedures.

Osteoporotic vertebral fracture: Our Experience and update

Introduction: Osteoporotic vertebral fracture is a fragility fracture due to osteoporosis and is a growing public health problem. It mainly affects postmenopausal women and men &gt; 50 years. It significantly affects morbidity, financial condition, quality of life and mortality of patients. It presents mainly with back pain, which is mostly manageable with conservative measures. Those with unrelieved pain, severe spinal deformity or neurological impairment would require intervention. The quality of bone and surgical fitness along with associated co-morbidities of these elderly people, require special consideration, indications and appropriate modification of technique and instruments for surgical intervention. Materials and methodology: This prospective study summarizes the management of osteoporotic vertebral fractures from September 2015 to September 2021 in Nepal Medical College, Kathmandu, Nepal. The study included patients with back pain of more than 50 years old age. The backpain was evaluated clinically using visual analogue scale and Oswestry Disability Index, neurological deficits using Frankel grading system and deformity using X-ray. Other investigations included MRI, Dexa scan, Serum calcium and Vitamin D3. Risk factors for developing osteoporosis and OVF were also assessed. Results: Out of the 630 patients of more than 50 years age, presenting in neurosurgical OPD with backache from September 2015 to September 2020, 158 cases were later diagnosed to have osteoporotic spine fractures. There were 122 (77.2%) postmenopausal ladies and 36 (22.8%) gentlemen. All had backpain, with 36% having VAS score of &lt; 3 and 64% had ODI of mild to moderate disability. The neurological deficits were present in 16.4% and mostly were Frankel grade C and D. Significant kyphoscoliosis (Cobb angle more than 20 degrees) in X-ray was present in 18 (11.3%) patients. 88 (55.7%) patients had Dexa scan and T score was less than -2.5 in 88 (56%). Serum calcium was low in (41) 26% and Vitamin D3 was low in (107) 67.7% of the patients. For backpain, all were started on non-operative management. Vertebral augmentation procedure was not available in our institute. Thus, surgery was offered in 44 (28%) of the patients but only 18 (11.4%) agreed for surgery and underwent decompression with long segment fixation. Only 48 patients remained in follow up for more than 2 years and all had satisfactory control of pain with no deterioration in deformity or neurological deficit. There were no significant short or long-term complications or mortality. Conclusion: Osteoporotic vertebral fracture is a very common reason for back pain in people of more than 50 years old affecting their livelihood. The majority responded to conservative treatment. Those indicated for surgery need special consideration in preparation, technique and devices. Preventive measures can help reduce the problem load.

Posterior Spinal Fusion for Severe Kyphosis in a Child with Gaucher Disease: A Case Report and Review of the Literature

Background: Skeleton involvement is one of the most significant aspects of Gaucher disease (GD). However, the treatment for spinal involvement in GD among patients undergoing enzyme replacement therapy (ERT) is poorly characterized. We present a case of progressive kyphotic spinal deformity in a young child caused by vertebral involvement, which was managed by posterior spinal fusion without anterior spinal release under ERT. Case presentation: This is a retrospective study. A 10-year-old boy presenting with progression kyphosis (thoracic kyphotic angle of 113°) associated with type-IIIb GD had undergone posterior spinal fusion with segmental pedicle screw fixation (from T6-L3) and Ponte osteotomy. The patient went back to school without further brace protection. Proximal junctional kyphosis (PJK) was observed at 4 months postoperatively. Revision surgery was performed to prevent neurological impairment. Additional posterior spinal fusion from T2–T6 and decompressive laminectomy were performed during the revision surgery. A 2-year follow-up showed no recurrence of PJK and solid fusion was achieved in the patient under ERT and brace protection. Conclusions: Posterior spinal fusion without anterior spinal release is a good treatment option for severe spinal deformity in patients with GD. However, the fusion level and reinforced fixation require careful consideration. Revision surgery and brace protection is needed as long as PJK is observed.

Effectiveness and safety of preoperative distraction using modified halo-pelvic Ilizarov distraction assembly in patients with severe kyphoscoliosis.

A 2-year follow-up study. To evaluate the effectiveness of modified halo-pelvic Ilizarov distraction assembly in the management of patients with severe kyphoscoliosis. Severe and rigid scoliosis curves are always a challenge for operating surgeons. Preoperative correction through halo-pelvic devices successfully minimizes the severity of the curve; however, cumbersome complications are also reported with its use. Modified assembly could be safe for these cases. Patients with severe kyphoscoliosis having coronal Cobb angle >90° were applied with modified halo-pelvic Ilizarov distraction assembly preoperatively. The modified assembly consisted of a pelvic component and halo ring, and distraction was given at the rate of 2-3 mm/day for 6-12 weeks. Complete clinical assessments along with pulmonary function tests were performed, and scoliosis series X-ray images were assessed for coronal and sagittal Cobb angle and other spinopelvic parameters before applying the assembly and during 2 years of follow-up. Thirty-four patients (age, 9-27 years; male/female ratio of 18:16) were included. The coronal and sagittal Cobb angles were 116°±16.2° and 84°±28.3°, respectively. Correction rates obtained through modified halo-pelvic assembly were nearly 52% (p=0.001) in coronal and 40% (p=0.001) in sagittal Cobb angles, with improvement in height (p=0.001). Apical vertebral translation and coronal balance were also improved significantly (p=0.001). Further improvements in all the parameters were obtained after definitive surgery, with improvements in the forced expiratory volume in 1 second (p =0.002) and forced vital capacity (p=0.001). Our modified halo-pelvic Ilizarov distraction assembly can achieve good correction in severe spinal deformities without significant risk to neurology, has fewer complications, and promotes good patient compliance.

A Successful Endotracheal Intubation of a Patient with Ankylosing Spondylitis: A Case Report

Background: Ankylosing spondylitis (AS) is a chronic inflammatory disorder that primarily affects the spine and eventually causes its malformation. Surgery is a common treatment for AS patients. Patients with severe AS usually have difficulty with ventilation or intubation. Therefore, airway management should be carefully evaluated, especially in patients with severe cervical deformities. Anesthesiologists must fully and carefully evaluate the airway in these patients. Case Presentation: A 49-year-old woman with AS suffered from a severe spinal deformity that required surgical treatment under general anesthesia. The patient was monitored for vital signs and adequately oxygenated. Lidocaine was used for cricothyroid puncture and throat anesthesia. The feasibility of tracheal intubation was assessed using a visual laryngoscope to expose the glottis under full surface anesthesia. Finally, a #7 enhanced tracheal catheter was successfully inserted after conventional sequential induction. The surgery was successfully completed, and the patient was discharged 10 days after surgery. Conclusions: Anesthesiologists should fully and carefully assess the presence of a difficult airway in patients with AS, whether it is difficult to ventilate or intubate. Adequate preparation plans are essential.

Implementing a Halo Gravity Traction Program: A Multidisciplinary Endeavor.

Halo gravity traction (HGT) is a preoperative modality for children with severe spinal deformity used to optimize spine flexibility and balance while decreasing the likelihood of neurologic injury. HGT is a dependable solution for these challenging spinal deformities. Aligning treatment guidelines and providing resources, education, and training for staff are key components for a successful HGT program. The HGT program at Children's Mercy Hospital was then developed with a systems approach with the holistic goal of multidisciplinary collaboration with physical/occupational therapy, hospital medicine, pulmonology, psychology, nutrition, child life, and complex care management. Education, research, and national collaboration to standardize this therapy should improve patient safety and support quality improvement.

Restoring L4-S1 Lordosis Shape in Severe Sagittal Deformity: Impact of Correction Techniques on Alignment and Complication Profile

Severe sagittal plane deformity with loss of L4-S1 lordosis is disabling and can be improved through various surgical techniques. However, data is limited on the differing ability of anterior lumbar interbody fusion (ALIF), pedicle subtraction osteotomy (PSO), and transforaminal lumbar interbody fusion (TLIF) to achieve alignment goals in severely malaligned patients. To examine surgical techniques aimed at restoring L4-S1 lordosis in severe adult spinal deformity (ASD). Retrospective review of prospectively collected data. A total of 96 patients who underwent ALIF, PSO, and TLIF were included in this study. The following data were observed for all cases: patient demographics, spinopelvic parameters, complications, and PROMs. Severe ASD patients with preoperative PI-LL >20°, L4-S1 lordosis <30°, and full body radiographs and patient-reported outcome measures (PROMs) at baseline and six-week postoperative visit were included. Patients were grouped into ALIF (1-2 level ALIF at L4-S1), PSO (L4/L5 PSO), and TLIF (1-2 level TLIF at L4-S1). Comparative analyses were performed on demographics, radiographic spinopelvic parameters, complications, and PROMs. Among the 96 included patients, 40 underwent ALIF, 27 underwent PSO, and 29 underwent TLIF. At baseline, cohorts had comparable age, sex, race, Edmonton frailty scores and radiographic spinopelvic parameters (p>0.05). However, PSO was performed more often in revision cases (p<0.001). Following surgery, L4-S1 lordosis correction (p=0.001) was comparable among ALIF and PSO patients and caudal lordotic apex migration (p=0.044) was highest among ALIF patients. PSO patients had higher intraoperative estimated blood loss (p<0.001) and motor deficits (p=0.049), and in-hospital ICU admission (p=0.022) and blood products given (p=0.004) but were otherwise comparable in terms of length of stay, blood transfusion given, and postoperative admission to rehab. Likewise, 90-day postoperative complication profiles and six-week PROMs were comparable as well. ALIF can restore L4-S1 sagittal alignment as powerfully as PSO, with fewer intra-operative and in-hospital complications. When feasible, ALIF is a suitable alternative to PSO and likely superior to TLIF for correcting L4-S1 lordosis among patients with severe sagittal malalignment.

Results of the Surgical Approach of Idiopathic Scoliosis in Adolescents and Postoperative Quality of Life: Systematic Literature Review.

Adolescent idiopathic scoliosis is considered the most severe and common spinal deformity, affecting children and adolescents still in the neuropsychomotor development phase before they reach skeletal maturity. This study aimed to evaluate the surgical approach to adolescent idiopathic scoliosis (AIS), considering the results associated with the reduction of pathological curvature, pulmonary function, and repercussions on the quality of life of adolescents undergoing such treatment. Systematic literature review, with a quantitative and qualitative approach to the data collected, structured according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), carried out in the databases linked to the Medical Literature Analysis and Retrieval System Online (MEDLINE) and Latin American and Caribbean Health Sciences Literature (LILACS). The total sample of the studies was 638 adolescents with AIS, with a mean age of 14.93 years ± 1.24. The mean correction of the main pathological curvature in the studies was 55.06% ± 12.24. In all of the selected studies using posterior spinal fusion to correct AIS, there was a significant reduction in pathological curvatures (> 49%), and the recurrence of curvature in none of the studies exceeded a pathological gain of more than 5%. As for lung function, the studies showed significant increases in forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) in patients with severe AIS, and no pulmonary function losses were reported after surgery to correct AIS.

A critical event frequent lead to reversible spinal cord injury during vertebral column resection surgery.

To report a "critical phase" (between osteotomy completion and correction beginning) that will frequently lead to the reversible intraoperative neurophysiological monitoring (IOM) change during posterior vertebral column resection (PVCR) surgery. The study sample consisted of 120 patients with severe spine deformity who underwent PVCR and deformity correction surgeries. Those patients were recruited consecutively from 2010 to 2018 January in our spine center. The detailed IOM data (the amplitude of MEP & SEP) and its corresponding surgical points were collected prospectively. Early and long-term postoperative neurologic outcomes were assessed for the following functions: motor, sensory, and pain at immediate postoperative and 1-year post-operation in this cases series. A total of 105 (105/120) patients presented varying degrees of IOM reduction in the critical phase; the mean IOM amplitude retention vs rescue rate was 27% ± 11.2 versus 58% ± 16.9, P < 0.01 (MEP) & 34% ± 8.3 versus 66% ± 12.4 P < 0.01 (SEP). Patients with postoperative spinal deficits often had a significantly longer IOM-alerting duration than the patients without (p < 0.01, Mann-Whitney U-test), and IOM-alerting duration greater than 39.5min was identified as an independent predictor of the risk of postoperative spinal deficits. The reversible IOM events probably often appear in the critical phase during PVCR surgery. The new postoperative spinal deficits are possible for patients without satisfied IOM recovery or alerting duration greater than 39.5min. Timely and suitable surgical interventions are useful for rescuing the IOM alerts.

Precise execution of personalized surgical planning using three-dimensional printed guide template in severe and complex adult spinal deformity patients requiring three-column osteotomy: a retrospective, comparative matched-cohort study

BackgroundThe surgical treatment of severe and complex adult spinal deformity (ASD) commonly required three-column osteotomy (3-CO), which was technically demanding with high risk of neurological deficit. Personalized three dimensional (3D)-printed guide template based on preoperative planning has been gradually applied in 3-CO procedure. The purpose of this study was to compare the efficacy, safety, and precision of 3D-printed osteotomy guide template and free-hand technique in the treatment of severe and complex ASD patients requiring 3-CO.MethodsThis was a single-centre retrospective comparative cohort study of patients with severe and complex ASD (Cobb angle of scoliosis > 80° with flexibility < 25% or focal kyphosis > 90°) who underwent posterior spinal fusion and 3-CO between January 2020 to January 2023, with a minimum 12 months follow-up. Personalized computer-assisted three-dimensional osteotomy simulation was performed for all recruited patients, who were further divided into template and non-template groups based on the application of 3D-printed osteotomy guide template according to the surgical planning. Patients in the two groups were age- and gender- propensity-matched. The radiographic parameters, postoperative neurological deficit, and precision of osteotomy execution were compared between groups.ResultsA total of 40 patients (age 36.53 ± 11.98 years) were retrospectively recruited, with 20 patients in each group. The preoperative focal kyphosis (FK) was 92.72° ± 36.77° in the template group and 93.47° ± 33.91° in the non-template group, with a main curve Cobb angle of 63.35° (15.00°, 92.25°) and 64.00° (20.25°, 99.20°), respectively. Following the correction surgery, there were no significant differences in postoperative FK, postoperative main curve Cobb angle, correction rate of FK (54.20% vs. 51.94%, P = 0.738), and correction rate of main curve Cobb angle (72.41% vs. 61.33%, P = 0.101) between the groups. However, the match ratio of execution to simulation osteotomy angle was significantly greater in the template group than the non-template group (coronal: 89.90% vs. 74.50%, P < 0.001; sagittal: 90.45% vs. 80.35%, P < 0.001). The operating time (ORT) was significantly shorter (359.25 ± 57.79 min vs. 398.90 ± 59.48 min, P = 0.039) and the incidence of postoperative neurological deficit (5.0% vs. 35.0%, P = 0.018) was significantly lower in the template group than the non-template group.ConclusionPerforming 3-CO with the assistance of personalized 3D-printed guide template could increase the precision of execution, decrease the risk of postoperative neurological deficit, and shorten the ORT in the correction surgery for severe and complex ASD. The personalized osteotomy guide had the advantages of 3D insight of the case-specific anatomy, identification of osteotomy location, and translation of the surgical planning or simulation to the real surgical site.

Hip Osteoarthritis in Patients Undergoing Surgery for Severe Adult Spinal Deformity: Prevalence and Impact on Spine Surgery Outcomes.

Hip osteoarthritis (OA) is common in patients with adult spinal deformity (ASD). Limited data exist on the prevalence of hip OA in patients with ASD, or on its impact on baseline and postoperative alignment and patient-reported outcome measures (PROMs). Therefore, this paper will assess the prevalence and impact of hip OA on alignment and PROMs. Patients with ASD who underwent L1-pelvis or longer fusions were included. Two independent reviewers graded hip OA with the Kellgren-Lawrence (KL) classification and stratified it by severity into non-severe (KL grade 1 or 2) and severe (KL grade 3 or 4). Radiographic parameters and PROMs were compared among 3 patient groups: Hip-Spine (hip KL grade 3 or 4 bilaterally), Unilateral (UL)-Hip (hip KL grade 3 or 4 unilaterally), or Spine (hip KL grade 1 or 2 bilaterally). Of 520 patients with ASD who met inclusion criteria for an OA prevalence analysis, 34% (177 of 520) had severe bilateral hip OA and unilateral or bilateral hip arthroplasty had been performed in 8.7% (45 of 520). A subset of 165 patients had all data components and were examined: 68 Hip-Spine, 32 UL-Hip, and 65 Spine. Hip-Spine patients were older (67.9 ± 9.5 years, versus 59.6 ± 10.1 years for Spine and 65.8 ± 7.5 years for UL-Hip; p < 0.001) and had a higher frailty index (4.3 ± 2.6, versus 2.7 ± 2.0 for UL-Hip and 2.9 ± 2.0 for Spine; p < 0.001). At 1 year, the groups had similar lumbar lordosis, yet the Hip-Spine patients had a worse sagittal vertebral axis (SVA) measurement (45.9 ± 45.5 mm, versus 25.1 ± 37.1 mm for UL-Hip and 19.0 ± 39.3 mm for Spine; p = 0.001). Hip-Spine patients also had worse Veterans RAND-12 Physical Component Summary scores at baseline (25.7 ± 9.3, versus 28.7 ± 9.8 for UL-Hip and 31.3 ± 10.5 for Spine; p = 0.005) and 1 year postoperatively (34.5 ± 11.4, versus 40.3 ± 10.4 for UL-Hip and 40.1 ± 10.9 for Spine; p = 0.006). This study of operatively treated ASD revealed that 1 in 3 patients had severe hip OA bilaterally. Such patients with severe bilateral hip OA had worse baseline SVA and PROMs that persisted 1 year following ASD surgery, despite correction of lordosis. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

P178 CXCL12/CXCR4-mediated osteogenic precursor cells recruitment: a key mechanism in ankylosing spondylitis-associated pathological bone formation

Abstract Background/Aims Ankylosing spondylitis (AS) is a debilitating condition characterised by severe spinal deformities, inflammation, and excessive bone formation, imposing significant socioeconomic burdens. Current treatments alleviate symptoms but fail to address bone structural damage. Pathological bone formation often occurs at entheses, where tendons and ligaments connect to bone. Osteogenic precursor cells (OPCs) play a crucial role, but their migration to new bone sites is poorly understood. C-X-C motif chemokine ligand 12 (CXCL12) is implicated in cell migration and bone-related processes, but its role in AS remains unclear. This study explores CXCL12/CXCR4 signalling in OPC recruitment and new bone formation, providing insights into AS pathogenesis and potential therapeutic targets. Methods We established mouse models, including the DBA/1 model, lipopolysaccharide-induced spondyloarthritis model, and Achilles tendon semi-transection model to confirm the role of CXCL12-Induced OPCs migration in pathological new bone formation. Additionally, genetically edited mouse models were generated to confirm the underlying mechanism of OPCs migration and their spatiotemporal phenotypes of differentiation, including DBA1;CXCL12 col2 transgenic mice, CXCL12hi/hi;Col2a1-creERT mice, and CXCR4fl/fl;Prx1-creERT mice. Results In this study, we have identified CXCL12 as a crucial contributor to the initiation of pathological new bone formation by recruiting OPCs. CXCL12 was highly expressed in regions predisposed to pathological bone development, attracting OPCs to these upregulated areas. Inhibiting the CXCL12/CXCR4 axis with AMD3100 or the conditional knockout of CXCR4 effectively reduced OPC migration and subsequent pathological bone formation in animal models of AS. Overexpression of CXCL12 in genetically engineered animals with a DBA/1 background demonstrated a stable joint ankylosis phenotype, providing a valuable model for the study of AS. Furthermore, our research revealed the indispensable role of Rac1 in OPC migration and the ensuing pathological bone formation. Conclusion This study elucidates the novel role of CXCL12 in AS and offers potential strategies for targeting the CXCL12/CXCR4-Rac1 axis to prevent the progression of axial skeletal ankylosis. Disclosure H. Cui: None. H. Liu: None.

Effectiveness and Safety of Preoperative Halo Gravity Traction-Assisted Posterior Spinal Fusion Surgery for Severe and Rigid Scoliosis: A Comparative Matched-Cohort Study

Background. Severe and rigid scoliosis poses significant challenges in surgical correction, and innovative approaches are continually sought to enhance effectiveness and ensure patient safety. Halo-gravity traction (HGT) continues to be a vital tool in managing severe spinal conditions, offering a nonsurgical or preoperative approach to address spinal deformities. However, the correction effect that HGT can achieve for severe and rigid spinal deformity is currently unclear and the impact of HGT on the selection of spinal osteotomy grade was still unknown. Methods. A retrospective matched-cohort study was conducted and a total of 74 patients from January 2018 to December 2021 in our institution were finally enrolled in this study, including 27 patients in the HGT group and 47 patients in the non-HGT group based on whether patients receive HGT or not. Comprehensive assessments including radiographic outcomes, surgical parameters, and clinical complications were collect and analyzed before and after correction surgery. Results. Of the patients included in the HGT group, 21 had thoracic curvature and 6 had thoracolumbar/lumbar curvature, compared with 38 and 9 in the non-HGT group, respectively (P=0.66). There was no significant difference in the etiologies of scoliosis between two groups (15/7/3/2 vs. 25/16/4/2, P=0.85). The main curve in HGT and non-HGT groups were corrected from an average of 113.69°–51.25° and 111.94°–63.79° (P&lt;0.01). For the HGT group, the mean correction rate of focal kyphosis (FK) was 45.43%, which was significantly higher than those in the non-HGT group (33.98%, P&lt;0.05). There were no statistically significant differences in preoperative parameters of sagittal vertical axis (SVA) (P=0.13) or thoracic kyphosis (TK) (P=0.07) between the two groups. Postoperatively, the HGT group showed significantly lower values in SVA (P=0.001) and TK (P=0.001) compared to the non-HGT group. However, there was no significant difference in the imaging parameters coronal vertical axis (CVA) and apical vertebral translation (AVT) between the two groups (P&gt;0.05). In the preoperative surgical planning phase before HGT treatment, 26 patients were initially considered candidates for 3-column osteotomy (3CO), while one patient was evaluated as suitable for posterior column osteotomy (PCO). Following HGT treatment, the assessment changed with 11 patients identified as candidates for 3CO and 16 patients deemed suitable for PCO. The application proportion of 3CO was significantly higher in the non-HGT group than in the HGT group (P&lt;0.05). The mean blood loss of the non-HGT group was significantly greater than that of the HGT group (666.67 ± 486.55 ml vs. 1024.47 ± 718.46 ml, P&lt;0.05), but the surgical time showed no difference between the two groups (297.33 ± 66.89 mins vs. 299.15 ± 56.73 mins, P=0.90). The incidence of complications in the HGT group was 7.4%, which was significantly lower than that of the non-HGT group (P&lt;0.05). Conclusion. This study showed that the use of HGT, as a feasible and safe strategy, has superior efficacy and safety for treating severe and rigid scoliosis and can reduce the level of osteotomy used during surgery to some extent.

Novel Surface Topographic Assessment of Lung Volume and Pulmonary Function Tests in Idiopathic Scoliosis: A Preliminary Study.

Severe spinal deformity results in restrictive pulmonary disease from thoracic distortions and lung-volume limitations. Though spirometry and body plethysmography are widely accepted tests for pulmonary function tests (PFTs), they are time-consuming and require patient compliance. This study investigates whether surface topographic [surface topography (ST)] measurements of body volume difference (BVD) and torso volume difference between maximum inhale and exhale correlate to values determined on PFTs. This study included patients with idiopathic scoliosis and thoracic/thoracolumbar curves ≥40 degrees. Patients received ST scans, clinical examinations, and EOS biplanar radiographs on the same day. PFTs were performed within 3 months of ST/radiographic analysis. Univariate linear regression analysis was used to examine relationships between BVD, PFT values, and mean curves. Sixteen patients (14.6 ± 2.2 y, 69% females) with idiopathic scoliosis and mean thoracic/thoracolumbar curves of 62 degrees ± 15˚ degrees (45 degrees to 93 degrees) were assessed. BVD displayed statistically high-positive positive correlations with forced vital capacity ( R = 0.863, P < 0.0001), forced expiratory volume in 1 second ( R = 0.870, P < 0.001), vital capacity ( R = 0.802, P < 0.0001), and TLC ( R = 0.831, P < 0.0001. Torso volume difference showed similarly high positive correlations to forced vital capacity, forced expiratory volume in 1 second, vital capacity, and TLC, but not residual volume. No correlations emerged between the mean thoracic/thoracolumbar curve and BVD or PFT values. This study strongly endorses further investigation into ST scanning as an alternative to traditional PFTs for assessing pulmonary volumes. The noncontact and noninvasive nature of ST scanning presents a valuable alternative method for analyzing thoracic volume, particularly beneficial for patients unable to cooperate with standard PFTs. Level II-prognostic.

Posterior vertebral column resection: Exploring practical uses in clinical settings.

The purpose of this study was to present our experience in patients who had been treated with posterior vertebral column resection (PVCR) for various spinal deformities. Thirty-seven patients who performed PVCR between 2015 and 2018 were evaluated retrospectively. The mean follow-up period was 24 months (range: 12-50 months). The demographic data of the patients, mean blood loss, amount of blood replacement, duration of operation, intensive care and hospitalization period, PVCR level, instrumentation level, amount of preoperative curvature, amount of postoperative curvature improvement, preoperative and postoperative neurological status, and complications were examined. Angular measurements were performed on X-ray. The mean age of the patients was 37.5 years (range: 3-80 years). PVCR was applied to patients due to different pathologies (congenital, tumor metastasis, posttraumatic kyphosis, revision scoliosis, and infection). The mean operation time was 445.5 min (260-720) with an average blood loss of 1903 ml (400-7000 ml). It was observed that the average local kyphosis angle decreased from 67.65° to 7.42° in 26 patients who were operated for advanced deformity (P < 0.001). When these values were compared in all 34 patients, the preoperative angle value decreased from 55.1° to 3.5° (P < 0.001) and decreased from 70° to 0° in 13 congenital kyphosis patients. PVCR is an effective method for correcting severe spinal deformities and can be used to correct curvature in different patient groups. Level 3.

Comparison of multilevel low-grade techniques versus three-column osteotomies in adult spinal deformity surgery: does harmonious correction matter?

Recent debate has arisen between whether to use a three-column osteotomy (3CO) or multilevel low-grade (MLG) techniques to treat severe sagittal malalignment in adult spinal deformity (ASD) surgery. The goal of this study was to compare the outcomes of 3CO and MLG techniques performed in corrective surgeries for ASD. ASD patients who had a baseline PI-LL > 30° and 2-year follow-up data were included. Patients underwent either 3CO or MLG (thoracolumbar posterior column osteotomies at ≥ 3 levels or anterior lumbar interbody fusion at ≥ 3 levels with no 3CO). The segmental utility ratio was used to assess relative segmental correction (segmental correction divided by overall correction in lordosis divided by the number of thoracolumbar interventions [interbody fusion, thoracolumbar posterior column osteotomies, and 3CO]). The paired t-test was used to assess lordotic distribution by differences in lordosis between adjacent lumbar disc spaces (e.g., L1-2 to L2-3). Multivariate analysis, controlling for age, sex, BMI, osteoporosis, baseline pelvic incidence, and T1 pelvic angle, was used to evaluate the complication rates and radiographic and patient-reported outcomes between the groups. A total of 93 patients were included, 53% of whom underwent MLG and 47% of whom underwent 3CO. The MLG group had a lower BMI (p < 0.05). MLG patients received fewer previous fusions than 3CO patients (31% vs 80%, p < 0.001). MLG patients had 24% less blood loss but a 22% longer operative time (565 vs 419 minutes, p = 0.008). Using adjusted analysis, the 3CO group had greater segmental and relative correction at each level (segmental utility ratio mean 69% for 3CO vs 23% for MLG, p < 0.001). However, the 3CO group had lordotic differences between two adjacent lumbar disc pairs (range -0.5° to 9.0°, p = 0.009), while MLG was more harmonious (range 2.2°-6.5°, p > 0.4). MLG patients were more likely to undergo realignment to age-adjusted standards (OR 5.6, 95% CI 1.2-46.4; p = 0.033). MLG patients were less likely to develop neurological complications or undergo reoperation (OR 0.4, 95% CI 0.1-0.9; p = 0.041). Adjusted analysis revealed that MLG patients more often met a substantial clinical benefit in the Oswestry Disability Index score (OR 5.3, 95% CI 1.1-26.8; p = 0.043). MLG techniques showed better utility in lumbar distribution and age-adjusted global correction while minimizing neurological complications and reoperation rates by 2 years postoperatively. In selected instances, these techniques may offer the spine deformity surgeon a safer alternative when correcting severe adult spinal deformity.

Advance in pediatric spinal cord injury

AbstractThe incidence rate of spinal cord injury in children is lower than that in adults, accounting for about 5% of all spinal cord injuries. Motor vehicle accidents are the main cause of spinal cord injuries in children. As the spine of children is still in the process of growth and development, the anatomical structure and biomechanics have unique characteristics, and its etiology, injury site, and clinical manifestations are different from those of adults. Misdiagnosis and delayed diagnosis can lead to severe spinal deformity and neurological complications. Children and adolescents with spinal cord injuries may suffer from lifelong disability, which will do great harm to children, families, and society. Early magnetic resonance imaging examination can effectively avoid underdiagnosis of spinal cord injury without radiographic abnormality and select appropriate treatment. In addition, it is also important to establish a family‐centered rehabilitation model to help the affected children reintegrate into society and achieve the goal of returning to normal life. This article reviews the etiology, epidemiology, clinical characteristics, complications, and treatment of spinal cord injury in children and adolescents.