Simplified S1 vertebral bone quality score independently predicts proximal junctional kyphosis after surgery for degenerative lumbar scoliosis.

OBJECTIVE: Our study aimed to assess the effectiveness of the simplified S1 vertebral bone quality (VBQ) score in predicting the incidence of proximal junctional kyphosis (PJK) after surgery for degenerative lumbar scoliosis (DLS). METHODS: We reviewed 122 patients with DLS who underwent posterior lumbar decompression and long-segment fusion surgery in our hospital from January 2016 to December 2020. The patients were classified into PJK group and non-PJK group. S1 VBQ scores are determined by signal intensity measurements taken from the mid-sagittal plane of T1-weighted non-contrast MRI. Logistic regression analysis was used to identify factors associated with PJK. Receiver-operating characteristic curve (ROC) analysis was used to evaluate the value of S1 VBQ score in predicting pedicle PJK after DLS. RESULTS: 122 DLS patients (90 females and 32 males) met the inclusion criteria. In addition, 27 patients (22.13%) had PJK at the time of last follow-up. VBQ was higher in PJK patients than non-PJK patients (3.58 ± 0.67 vs. 3.08 ± 0.54, p < 0.001). Preoperatively, patients in the PJK group had a greater TLK than those in the non-PJK group (20.00 ± 6.22 vs. 16.86 ± 5.38, p = 0.011). After surgery, patients in the PJK group had greater TLK (p < 0.001) and PJA (p < 0.001) compared with the non-PJK group. At final FU, patients in the PJK group had greater TK (p = 0.002), TLK (p < 0.001), SVA (p < 0.001), and PJA (p < 0.001) than patients in the non-PJK group (Table 4). In multivariate logistic regression analysis, higher VBQ score (OR 4.565, 95% CI 1.43-14.568, p = 0.010), advanced age (OR 1.119, 95% CI 1.021-1.227, p = 0.016), and larger TLK (OR 1.191, 95% CI 1.041-1.362, p = 0.011) were significant predictors of postoperative PJK in patients with DLS (Table 6). A statistically significant positive correlation existed between VBQ score and PJA change (r = 0.370, p < 0.001). We created ROC curves for VBQ scores as predictors of PJK with a diagnostic accuracy of 72.1% (95% CI 60.15-82.9%.The ideal limit for the VBQ score was 3.205 (sensitivity: 77.8%, specificity: 81.4%). CONCLUSION: To the best of our knowledge, this is the first study to evaluate the effectiveness of the S1 VBQ score in predicting postoperative PJK in DLS. Our study included major risk factors and found that S1 VBQ score was a significant predictor of PJK in patients undergoing DLS surgery. The higher the S1 VBQ score, the higher the probability of PJK.

Non-traumatic complete cervical spine dislocation with severe fixed kyphosis: successful multidisciplinary approach to a challenging case.

BACKGROUND: To our knowledge, there is no previous report in the literature of non-traumatic neglected complete cervical spine dislocation characterized by anterior spondyloptosis of C4, extreme head drop, and irreducible cervicothoracic kyphosis. CASE PRESENTATION: We report the case of a 33-year-old Caucasian man with a 17-year history of severe immune polymyositis and regular physiotherapy who presented with severe non-reducible kyphosis of the cervicothoracic junction and progressive tetraparesia for several weeks after a physiotherapy session. Radiographs, computed tomography, and magnetic resonance imaging revealed a complete dislocation at the C4-C5 level, with C4 spondyloptosis, kyphotic angulation, spinal cord compression, and severe myelopathy. Due to recent worsening of neurological symptoms, an invasive treatment strategy was indicated. The patient's neurological status and spinal deformity greatly complicated the anesthetic and surgical management, which was planned after extensive multidisciplinary discussion and relied on close collaboration between the orthopedic surgeon and the anesthetist. Regarding anesthesia, difficult airway access was expected due to severe cervical angulation, limited mouth opening, and thyromental distance, with high risk of difficult ventilation and intubation. Patient management was further complicated by a theoretical risk of neurogenic shock, motor and sensory deterioration, instability due to position changes during surgery, and postoperative respiratory failure. Regarding surgery, a multistage approach was carefully planned. After a failed attempt at closed reduction, a three-stage surgical procedure was performed to reduce displacement and stabilize the spine, resulting in correct spinal realignment and fixation. Progressive complete neurological recovery was observed. CONCLUSION: This case illustrates the successful management of a critical situation based on a multidisciplinary collaboration involving radiologists, anesthesiologists, and spine surgeons.

[Current status of surgical treatment for angular kyphosis in spinal tuberculosis].

Objective: To review current status of surgical treatment for angular kyphosis in spinal tuberculosis and provide reference for clinical treatment. Methods: The literature on the surgical treatment for angular kyphosis of spinal tuberculosis in recent years was extensively reviewed and summarized from the aspects of surgical indications, surgical contraindications, surgical approach, selection of osteotomy, and perioperative management. Results: Angular kyphosis of spine is a common complication in patients with spinal tuberculosis. If kyphosis progresses gradually, it is easy to cause neurological damage, deterioration, and delayed paralysis, which requires surgical intervention. At present, surgical approaches for angular kyphosis of the spine include anterior approach, posterior approach, and combined anterior and posterior approaches. Anterior approach can be performed for patients with severe spinal cord compression and small kyphotic Cobb angle. Posterior approach can be used for patients with large kyphotic Cobb angle but not serious neurological impairment. A combined anterior and posterior approaches is an option for spinal canal decompression and orthosis. Osteotomy for kyphotic deformity include Smith-Peterson osteotomy (SPO), pedicle subtraction osteotomy (PSO), vertebral column resection(VCR), vertebral column decancellation (VCD), posterior vertebral column resection (PVCR), deformed complex vertebral osteotomy (DCVO), and Y-shaped osteotomy. SPO and PSO are osteotomy methods with relatively low surgical difficulty and low surgical risks, and can provide 15°-30° angular kyphosis correction effect. VCR or PVCR is a representative method of osteotomy and correction. The kyphosis correction can reach 50° and is suitable for patients with severe angular kyphosis. VCD, DCVO, and Y-shaped osteotomy are emerging surgical techniques in recent years. Compared with VCR, the surgical risks are lower and the treatment effects also improve to varying degrees. Postoperative recovery is also a very important part of the perioperative period and should be taken seriously. Conclusion: There is no consensus on the choice of surgical treatment for angular kyphosis in spinal tuberculosis. Osteotomy surgery are invasive, which is a problem that colleagues have always been concerned about. It is best to choose a surgical method with less trauma while ensuring the effectiveness.

Aggressive vertebral hemangiomas contain no adipose tissue resulting in thoracic spine kyphosis: A case report.

RATIONALE: Aggressive vertebral hemangiomas (AVHs) destroy continuous vertebral bodies and intervertebral discs and resulting in spinal kyphosis is extremely rare. The very aggressive behavior was attributable to its significant vascular component and contained no adipose tissue. PATIENT CONCERNS: We report a case of thoracic spine kyphosis of AVHs with multiple vertebral bodies and intervertebral disc destruction in a 45-year-old woman. DIAGNOSES: Based on the imaging studies, the patient underwent surgical removal of this lesion and spinal reconstruction. Histopathology consistent with vertebral hemangioma and contained no adipose. INTERVENTIONS: The patient underwent surgical removal of the lesion and spinal reconstruction. After subperiosteal dissection of the paraspinal muscles and exposure of the laminae, the laminae of the T5-7 vertebrae were removed and exposing the lesion. The lesion was soft and showed cystic changes, completely curetted and autogenous bone was implanted. Vertebroplasty was performed through T3-T9 pedicles bilaterally. Pedicle screw fixation was performed for segmental fixation and fusion. OUTCOMES: After 9 days of operation, the incision healed cleanly and free of pain. She was discharged in good general condition. The patient remained asymptomatic after follow-up 6 months of postoperative. LESSONS: AVHs destroy multiple vertebral bodies and intervertebral discs and resulting in spinal kyphosis is extremely rare.

Percutaneous kyphoplasty through unilateral puncture on the convex side for the treatment of painful osteoporotic vertebral compression fracture with scoliosis.

PURPOSE: To assess the clinical safety, accuracy, and efficacy of percutaneous kyphoplasty (PKP) surgery using an enhanced method of unilateral puncture on the convex side for the treatment of painful osteoporotic vertebral compression fractures (P-OVCF) with scoliosis. METHODS: Clinical and radiographic data of P-OVCF patients with scoliosis who underwent PKP via unilateral puncture on the convex side from January 2018 to December 2021 were retrospectively analyzed. This technique's detailed surgical steps and tips were described. The local kyphosis angle (LKA), scoliosis Cobb angle (SCA), and local scoliosis Cobb angle (LSCA) were measured using X-ray and compared at pre-operation, post-operation, and the last follow-up. The width of pedicle (POW), inner inclination angle (IIA), lateral distance (LD), and puncture course length (PCL) were measured on the axial computed tomography image and compared between two sides. Postoperative computed tomography was employed to evaluate the condition of cement distribution and puncture. Clinical outcomes were evaluated using the Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for back pain (BP). RESULTS: Thirty-six patients, 23 women and 13 men, with an average age of 76.31 ± 6.28 years were monitored for 17.69 ± 4.70 months. The median surgical duration of single vertebrae was 35 min. The volume of bone cement for single vertebrae was 3.81 ± 0.87 ml and the proportion of sufficient cement distribution of the patients was 97.22. LKA was considerably improved from pre-operation to post-operation and sustained at the last follow-up. SCA and LSCA were not significantly modified between these three-time points. IIA, PCL, and LD were lower on the convex side than on the concave side. POW was considerably wider on the convex side. The ODI and VAS-BP scores were significantly improved after surgery and sustained during the follow-up. CONCLUSIONS: Combining with the proper assessment of the pre-injured life status of patients, PKP surgery using unilateral puncture on the convex side for the treatment of P-OVCF with scoliosis can achieve safe, excellent clinical, and radiographic outcomes.

Percutaneous Curved Vertebroplasty Decrease the Risk of Cemented Vertebra Refracture Compared with Bilateral Percutaneous Kyphoplasty in the Treatment of Osteoporotic Vertebral Compression Fractures.

Purpose: The purpose of this study is to compare the refracture rate of the cemented vertebral body of percutaneous curved vertebroplasty (PCVP) and bilateral percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral compression fractures (OVCF). Methods: Ninety-four patients with single segment thoracolumbar OVCF were randomly divided into two groups (47 patients in each) and underwent PCVP or bilateral PKP surgery, respectively. Refracture of cemented vertebral body, bone cement injection volume and cement pattern, cement leakage rate, total surgical time, intraoperative fluoroscopy time, preoperative and postoperative Cobb angles and anterior vertebral height, Oswestry disability index questionnaire (ODI) and visual analog scales (VAS) were recorded. Results: The PCVP group had significantly lower refracture incidence of the cemented vertebral than the bilateral PKP group (p<0.05). There was a significant postoperative improvement in the VAS score and ODI in both group (p<0.01), and no significant difference was found between two groups. The operation time and intraoperative fluoroscopy times were significantly less in the PCVP group than in the bilateral PKP group (p<0.01). The mean kyphosis angle correction and vertebral height restoration in the PCVP group was significantly less than that in the bilateral PKP group (p<0.01). Conclusion: Both PCVP and PKP were safe and effective treatments for OVCF. The PCVP had lower refracture rate of the cemented vertebral than the bilateral PKP group, and PCVP entailed less exposure to fluoroscopy and shorter operation time than bilateral PKP.

[Effect of Kümmell's disease with kyphosis on spinal-pelvic sagittal parameters].

OBJECTIVE: To explore the effect of Kümmell's disease with kyphosis on the sagittal morphology of the spine-pelvis. METHODS: A retrospective analysis of 34 patients of Kümmell's disease with kyphosis （Kümmell group） admitted from August 2015 to September 2022, including 10 males and 24 females with an average age of （71.1±8.5） years old. A control group of 37 asymptomatic population aged （69.3±6.7） years old was matched. Spinal-pelvic sagittal parameters were measured on the anterior-posterior and lateral X-rays of the whole spine in the standing position, including segmental kyphosis（SK） or thoracolumbar kyphosis（TLK）, thoracic kyphosis（TK）, lumbar lordosis（LL）, pelvic incidence（PI）, pelvic tilt（PT）, sacral slope（SS）, sagittal vertical axis（SVA）, T1 pelvic angle（TPA） and PI-LL. Vertebral wedge angle（WA） in Kümmell was measured and differences in parameters among groups were analyzed and the relationship between spino-pelvic parameters and WA, SK were also investigated. RESULTS: TK, SK, PT, SVA, TPA and PI-LL in Kümmell group were significantly larger than those in control group （P<0.05）, LL and SS in Kümmell group were significantly decreased than those in control group （P<0.05）, and there was no significant difference in PI between two groups （P>0.05）. In Kümmell group, WA（30.8±5.9）° showed a positive correlation with SK and TK（r=0.366, 0.597, P<0.05）, and SK was significantly correlated with LL and SS（r=0.539, -0.591, P<0.05）. Strong positive correlation between LL and PI, SS, SVA, TPA, PI-LL were also confirmed in patients with Kümmell with kyphosis（r=0.559, 0.741, -0.273, -0.356, -0.882, P<0.05）. CONCLUSION: Patients with Kümmell with kyphosis not only have segmental kyphosis, but also changes the overall spinal-pelvic sagittal parameters, including loss of lumbar lordosis, pelvic retrorotation, trunk forward tilt. The surgical treatment of Kümmell disease should not only pay attention to the recovery of the height of the collapsed vertebra, but also focus on the overall balance of the spine-pelvic sagittal plane for patients with kyphosis.

Is The Modular Dynamic System as Effective as Classical Dynamic Systems in Long Segment Dynamic Thoracolumbar Stabilization?

AIM: To evaluate the outcomes of dynamic stabilization in the multilevel degenerative spondylotic spine, and to compare the two dynamic systems (Dynesys® and Orthrus®) to reveal the increasing role of dynamic systems in the management of the degenerative spine. MATERIAL AND METHODS: A total of 74 patients who received dynamic stabilization for degenerative pathologies were retrospectively analyzed. Demographic details: preoperative data including neurological status, pain scores, and radiology; and intraoperative data including blood loss, duration of surgery, complications, and postoperative data including the neurologic status, duration of hospital stay, and pain scores were examined. RESULTS: Patients in both groups showed statistically significant improvements in their Visual Analog Scale and Oswestry Disability Index scores. Significant corrections of thoracic kyphosis (T2-T12), the sagittal vertical axis, and T10-L2 thoracolumbar kyphosis were obtained in our cohort (p < 0.05). A total of 4 patients received revision surgery due to screw loosening. Patients were discharged after 3-4 days and mobilized on the first postoperative day. CONCLUSION: We did not experience any serious issues in terms of stabilization in the cases in which we employed both systems. Our patients' clinical results were satisfactory in both systems. Existing systems can be used safely even in long-segment stabilization surgeries.

Hybrid kyphoplasty with short-versus intermediate- and long-segment pedicle screw fixations for the management of thoracolumbar burst fractures.

BACKGROUND: This study aimed to determine if the hybrid short-segment (HSS) technique is a good alternative to the intermediate-segment (IS) and long-segment (LS) techniques in pedicle screw fixations for acute thoracolumbar burst fractures (TLBFs). METHODS: In this retrospective evaluation, we examined 43 patients who underwent surgical treatments, including one- or two-level suprajacent (U) and infrajacent (L) pedicle screw fixations, for acute single-level TLBFs with neurological deficits between the T11 and L2 levels from July 2013 to December 2019. Among these patients, 15 individuals underwent HSS (U1L1), 12 received IS (U2L1), and 16 underwent LS (U2L2) fixations. Supplemental kyphoplasty of the fractured vertebral bodies was performed exclusively in the HSS group. Our analysis focused on assessing blood loss and surgical duration. Additionally, we compared postoperative thoracolumbar kyphotic degeneration using the data on Cobb angles on lateral radiographic images acquired at three time points (preoperatively, postoperative day 1, and follow-up). The end of follow-up was defined as the most recent postoperative radiographic image or implant complication occurrence. RESULTS: Blood loss and surgical duration were significantly lower in the HSS group than in the IS and LS groups. Additionally, the HSS group exhibited the lowest implant complication rate (2/15, 13.33%), followed by the LS (6/16, 37.5%) and IS (8/12, 66.7%) group. Implant complications occurred at a mean follow-up of 7.5 (range: 6-9), 9 (range: 5-23), and 7 (range: 1-21) months in the HSS, IS, and LS groups. Among these implant complications, revision surgeries were performed in two patients in the HSS group, two in the IS group, and one in the LS group. One patient treated by HSS with balloon kyphoplasty underwent reoperation because of symptomatic cement leakage. CONCLUSIONS: The HSS technique reduced intraoperative blood loss, surgical duration, and postoperative implant complications, indicating it is a good alternative to the IS and LS techniques for treating acute single-level TLBFs. This technique facilitates immediate kyphosis correction and successful maintenance of the corrected alignment within 1 year. Supplemental kyphoplasty with SpineJack® devices and high-viscosity bone cements for anterior reconstruction can potentially decrease the risk of cement leakage and related issues.

Spinal Manifestations of Skeletal Dysplasia: A Practical Guide for Clinical Diagnosis.

Skeletal dysplasias are a group of genetic conditions defined by atypical bone or cartilage growth and development. Skeletal abnormalities include short stature, limb deformity, joint contracture, and spinal deformity. Over 90% of disorders have a known genetic mutation that can definitively determine the diagnosis. As patients may present with a primary spinal concern, a careful clinical and radiographic evaluation can allow the physician to develop a working diagnosis to guide additional evaluation. Spinal manifestations include scoliosis and kyphoscoliosis, cervical instability, cervical kyphosis, thoracolumbar kyphosis, spinal stenosis, and atypical vertebral body morphology. An understanding of the affected conditions, prevalence, and natural history of these radiographic findings aids the orthopaedic surgeon in establishing a diagnosis and guides appropriate orthopaedic care.

Surgical limits, pitfalls, and potential solutions in kyphectomy in myelomeningocele: three cases and systematic review of the literature.

OBJECTIVES: To describe surgical treatment of 3 cases of severe and progressive thoracolumbar kyphosis in myelomeningocele and provide a systematic review of the available literature on the topic. METHODS: Medical records and pre- and post-operative imaging of 3 patients with thoracolumbar kyphosis and myelomeningocele were reviewed. A database search was performed for all manuscripts published on kyphectomy and/or surgical treatment of kyphosis in myelomeningocele. Patients' information, preoperative kyphosis angle, type of surgery, levels of surgery degrees of correction after surgery and at follow-up, and complications were reviewed for the included studies. RESULTS: Three cases underwent posterior vertebral column resection (pVCR) of 2-4 segments at the apex of the kyphosis (kyphectomy). Long instrumentation was performed with all pedicle screws constructed from the thoracic spine to the pelvis using iliac screws. According to literature review, a total of 586 children were treated for vertebral kyphosis related to myelomeningocele. At least one vertebra was excised to gain some degree of correction of the deformity. Different types of instrumentation were used over time and none of them demonstrated to be superior over the other. CONCLUSION: Surgical treatment of progressive kyphosis in myelomeningocele has evolved over the years incorporating all major advances in spinal instrumentation techniques. Certainly, the best results in terms of preservation of correction after surgery and less revision rates were obtained with long construct and screws. However, complication rate remains high with skin problems being the most common complication. The use of low-profile instrumentation remains critical for treatment of these patients.

Surgical outcome after treatment of thoracolumbar spinal stenosis in adults with achondroplasia.

PURPOSE: To describe the complications and the outcome of patients with achondroplasia undergoing thoracolumbar spinal surgery. METHODS: Retrospective analysis of prospectively collected data of all patients with achondroplasia undergoing surgery within the years 1992-2021 at the thoracic and/or lumbar spine. The outcome was measured by analyzing the surgical complications and revisions. The patient-rated outcome was assessed with the COMI score from 2005 onwards. RESULTS: A total of 15 patients were included in this study undergoing a total of 31 surgeries at 79 thoracolumbar levels. 12/31 surgeries had intraoperative complications consisting of 11 dural tears and one excessive intraoperative bleeding. 4/18 revision surgeries were conducted due to post-decompression hyperkyphosis. The COMI score decreased from 7.5 IQR 1.4 (range 7.1-9.8) preoperatively to 5.3 IQR 4.1 (2.5-7.5) after 2 years (p = 0.046). CONCLUSION: Patients with achondroplasia, the most common skeletal dysplasia condition with short-limb dwarfism, are burdened with a congenitally narrow spinal canal and are commonly in need of spinal surgery. However, surgery in these patients is often associated with complications, namely dural tears and post-decompression kyphosis. Despite these complications, patients benefit from surgical treatment at a follow-up of 2 years after surgery.

Kyphectomy and sliding growing rod technique in patients with congenital lumbar kyphosis deformity with myelomeningocele.

OBJECTIVE: Neural tube defects are the most common congenital disorders after cardiac anomalies. Lumbar kyphosis deformity is observed in 8-15% of these patients. This deformity severely limits the daily lives of these patients. In our study, we aimed to correct the kyphosis angle of the patients with lumbar kyphosis associated with myelomeningocele (MMC) and allow them to continue their growth without limiting their lung capacity by applying kyphectomy and sliding growing rod technique. PATIENTS AND METHODS: In this study, we retrospectively evaluated 24 patients with congenital lumbar kyphosis deformity associated with MMC, aged between 4 and 9 years, and who applied to Umraniye Training and Research Hospital between the dates of 2018 and 2021. We evaluated preoperative and postoperative kyphosis angles, correction rates, bleeding during operations, operation time, level of instrumentation, number of the resected vertebrae, initial levels of the posterior defects, duration of hospital stays, annual lengthening, and weight of the patients. RESULTS: Mean age was 5.04 (between 4 and 9). Mean preoperative and early postoperative kyphosis angles were 129.8° (87-175°) and 0.79° (- 20-24°), respectively. The kyphotic deformity correction rate was 99.1%. A difference was found regarding kyphosis measurements between preoperative and early period values (p < 0.05). The annual height lengthening of patients was calculated as 0.74 cm/year and 0.77 cm/year between T1-T12 and T1-S1, respectively. Mean preoperative level of hemoglobin (Hgb) was 11.95, postoperative Hgb value was 10.02, and the decrease was significant (p < 0.05). In terms of complications, 50% (12) had broken/loosen screws, 50% (12) had undergone debridement surgery, 37.5% (9) had vacuum-assisted closure therapy, and 33.3% (8) had to get all of their implants removed. CONCLUSION: We believe that our sliding growing rod technique is a new and updated surgical method that can be applied in these patient groups, facilitating the life, rehabilitation process, and daily care of MMC patients with lumbar kyphosis. This technique seems to be a safe and reliable method which preserves lung capacity and allows lengthening.

T1 Pedicle Subtraction Osteotomy With Subaxial Cervical Pedicle Screw Fixation.

Patients suffering from ankylosing spondylitis are not only predisposed to the development of rigid cervicothoracic deformities but are also at an increased risk of cervical fractures. Deformity correction and stabilization are particularly challenging in this patient population due to the brittle bone quality and low bone mineral density. Thoracic pedicle subtraction osteotomy is a workhorse approach for the correction of focal severe kyphotic deformity with lower complication rates than 3-column osteotomy. Successful execution of an upper thoracic PSO requires careful presurgical planning as well as anticipation of the patient's postoperative needs. Here, we describe the use of a T1 PSO in the correction of a rigid cervicothoracic chin-on-chest deformity in a patient with AS. The risk of implant failure was reduced by the use of a multi-rod construct, navigated cervical pedicle screws, and dual-pitched thoracic pedicle screws.

Distal Junctional Failures in Degenerative Thoracolumbar Hyperkyphosis.

OBJECTIVE: Degenerative thoracolumbar hyperkyphosis (DTH) is a disease that negatively affects individual health and requires surgical intervention, yet the ideal surgical approach and complications, especially distal junctional failures (DJF), remain poorly understood. This study aims to investigate DJF in DTH and to identify the risk factors for DJF so that we can improve surgical decision-making, and advance our knowledge in the field of spinal surgery to enhance patient outcomes. METHODS: This study retrospectively reviewed 78 cases (late osteoporotic vertebral compression fracture [OVCF], 51; Scheuermann's kyphosis [SK], 17; and degenerative disc diseases [DDD], 10) who underwent corrective surgery in our institute from 2008 to 2019. Clinical outcomes were assessed using health-related quality of life (HRQOL) measures, including the visual analogue scale (VAS) scores for back and leg pain, the Oswestry disability index (ODI), and the Japanese Orthopaedic Association (JOA) scoring system. Multiple radiographic parameters, such as global kyphosis (GK) and thoracolumbar kyphosis (TLK), were assessed to determine radiographic outcomes. Multivariate logistic regression analysis was employed to identify the risk factors associated with DJF. RESULTS: HRQOL improved, and GK, TLK decreased at the final follow-up, with a correction rate of 67.7% and 68.5%, respectively. DJF was found in 13 of 78 cases (16.7%), two cases had wedging in the disc (L3-4) below the instrumentation, one case had a fracture of the lowest instrumented vertebrae (LIV), one case had osteoporotic fracture below the fixation, nine cases had pull-out or loosening of the screws at the LIV and three cases (23.1%) required revision surgery. The DJF group had older age, lower computed tomography Hounsfield unit (CT HU), longer follow-up, more blood loss, greater preoperative sagittal vertical axis (SVA), and poorer postoperative JOA and VAS scores (back). The change in TLK level was larger in the non-DJF group. Post-sagittal stable vertebrae (SSV) moved cranially compared with pre-SSV. CONCLUSION: Age, CT HU, length of follow-up, estimated blood loss, and preoperative SVA were independent risk factors for DJF. We recommend fixation of the two vertebrae below the apex vertebrae for DTH to minimize surgical trauma.

Is Proximal Triangular Fixation Better than the Conventional Method in Adult Spinal Deformity Surgery?

In adult spinal deformity (ASD) surgery, one of the key factors working to prevent proximal junctional kyphosis is the proximal anchor. The aim of this study was to compare clinical and radiographic outcomes of triangular fixation with conventional fixation as proximal anchoring techniques in ASD surgery. We retrospectively evaluated 54 patients who underwent corrective spinal fusion for ASD. Fourteen patients underwent proximal triangular fixation (Group T; average 74.6 years), and 40 patients underwent the conventional method (Group C; average 70.5 years). Clinical and radiographic outcomes were assessed using visual analogue scale (VAS) values for back pain and the Oswestry disability index (ODI). Radiographic evaluation was also collected preoperatively and postoperatively. Surgical times and intraoperative blood loss of the two groups were not significantly different (493 vs 490 min, 1,260 vs 1,173 mL). Clinical outcomes such as VAS and ODI were comparable in the two groups. Proximal junctional kyphosis in group T was slightly lower than that of group C (28.5% vs 47.5%, p=0.491). However, based on radiology, proximal screw pullout occurred significantly less frequently in the triangular fixation group than the conventional group (0.0% vs 22.5%, p=0.049). Clinical outcomes in the two groups were not significantly different.

Characteristics and standards of severe sagittal imbalance in adult patients with spinal deformities: a retrospective analysis.

OBJECTIVE: To analyze the characteristics of "severe" dynamic sagittal imbalance (DSI) in patients with adult spinal deformity (ASD) and establish criteria for them. METHODS: We retrospectively analyzed 102 patients with ASD presenting four cardinal signs of lumbar degenerative kyphosis. All patients underwent deformity corrective surgery and were divided into three groups according to the diagnostic criteria based on the Oswestry disability index and dynamic features (△Timewalk: time until C7 sagittal vertical axis [C7SVA] reaches ≥ 20 cm after the start of walking) of sagittal imbalance. The paravertebral back muscles were analyzed and compared using T2-weighted axial imaging. We performed a statistically time-dependent spinopelvic sagittal parameter analysis of full standing lateral lumbar radiographs. Lumbar flexibility was analyzed using dynamic lateral lumbar radiography. RESULTS: The patients were classified into the mild (△Timewalk ≥ 180 s, 35 patients), moderate (180 s > △Timewalk ≥ 30 s, 38 patients), and severe (△Timewalk < 30 s, 29 patients) groups. The back muscles in the severe group exhibited a significantly higher signal intensity (533.4 ± 237.5, p < 0.05) and larger area of fat infiltration (35.2 ± 5.4, p < 0.05) than those in the mild (223.8 ± 67.6/22.9 ± 11.9) and moderate groups (294.4 ± 214.7/21.6 ± 10.6). The analysis of lumbar flexibility revealed significantly lower values in the severe group (5.8° ± 2.5°, p < 0.05) than in the mild and moderate groups (14.2° ± 12.4° and 11.4° ± 8.7°, respectively). The severe group had significantly lower lumbar lordosis (LL, 25.1° ± 22.7°, p < 0.05) and Pelvic incidence-LL mismatch (PI-LL, 81.5° ± 26.6°, p < 0.001) than those of the mild (8.2° ± 16.3°/58.7° ± 18.8°) and moderate (14.3° ± 28.6°/66.8° ± 13.4°) groups. On receiver operating characteristic curve analysis, PI-LL was statistically significant, with an area under the curve of 0.810 (95% confidence interval) when the baseline was set at 75.3°. The severe group had more postoperative complications than the other groups. CONCLUSIONS: Our results suggest the following criteria for severe DSI: C7SVA > 20 cm within 30 s of walking or standing, a rigid lumbar curve < 10° on dynamic lateral radiographs, and a PI-LL mismatch > 75.3°.

Navigation-Assisted One-Staged Posterior Spinal Fusion Using Pedicle Screw Instrumentation in Adolescent Idiopathic Scoliosis-A Case Series.

Background and Objectives: Adolescent idiopathic scoliosis (AIS) is a prevalent three-dimensional spinal disorder, with a multifactorial pathogenesis, including genetics and environmental aspects. Treatment options include non-surgical and surgical treatment. Surgical interventions demonstrate positive outcomes in terms of deformity correction, pain relief, and improvements of the cardiac and pulmonary function. Surgical complications, including excessive blood loss and neurologic deficits, are reported in 2.27-12% of cases. Navigation-assisted techniques, such as the O-arm system, have been a recent focus with enhanced precision. This study aims to evaluate the results and complications of one-stage posterior instrumentation fusion in AIS patients assisted by O-arm navigation. Materials and Methods: This retrospective study assesses 55 patients with AIS (12-28 years) who underwent one-stage posterior instrumentation correction supported by O-arm navigation from June 2016 to August 2023. We examined radiological surgical outcomes (initial correction rate, loss of correction rate, last follow-up correction rate) and complications as major outcomes. The characteristics of the patients, intraoperative blood loss, operation time, number of fusion levels, and screw density were documented. Results: Of 73 patients, 55 met the inclusion criteria. The average age was 16.67 years, with a predominance of females (78.2%). The surgical outcomes demonstrated substantial initial correction (58.88%) and sustained positive radiological impact at the last follow-up (56.56%). Perioperative complications, including major and minor, occurred in 18.18% of the cases. Two patients experienced a major complication. Blood loss (509.46 mL) and operation time (402.13 min) were comparable to the literature ranges. Trend analysis indicated improvements in operation time and blood loss over the study period. Conclusions: O-arm navigation-assisted one-stage posterior instrumentation proves reliable for AIS corrective surgery, achieving significant and sustained positive radiological outcomes, lower correction loss, reduced intraoperative blood loss, and absence of implant-related complications. Despite the challenges, our study demonstrates the efficacy and maturation of this surgical approach.

Defining threshold for sagittal correction in lumbar fractures.

PURPOSE: Surgical indications for thoraco-lumbar fractures are driven both by neurological status, fractures instability and kyphotic deformity. Regarding kyphotic deformity, an angulation superior to 20° is considered by many surgeons as a surgical indication to reduce the disability induced by post-traumatic kyphosis. However, there is a lack of data reporting the ideal or theoretical lordosis that one must have in a particular lumbar segment on CT-scan. The main goal of this study was to determine the mean value for segmental lumbar lordosis according to pelvic incidence (PI) on a cohort of normal subjects. METHODS: The consecutive CT-scan of 171 normal adult subjects were retrospectively analyzed. The PI and the segmental lordosis (L4S1, L3L5, L2L4, L3L1, L2T12 and T11-L1) were measured on all CT-scan. The mean values were calculated for the global cohort and a sub-group analysis according to IP ranges (< 45°, 45 < IP < 60° and > 60°) was performed. RESULTS: The mean angular values for the whole cohort were IP: 54, 9°; L4S1: - 38, 1°; L3L5: - 30, 6°; L2L4: - 14, 1°; L1L3: - 4, 9°; T12L2: + 1, 9° and T11L1: + 5, 4°. The segmental values vary significatively with PI ranges, as for L3L5: - 26, 8° (PI < 45°); - 30° (45 < PI < 60°) and - 35, 1° (PI > 60°). CONCLUSION: These results provide a referential of theoretical values of segmental lordosis according to PI. This abacus may help spinal surgeon in their decision-making process regarding lumbar fractures, to determine the amount of sagittal correction needed, according to the PI range, to be adapted to the sagittal morphology of the patient. LEVEL OF EVIDENCE: III.

Treatment of kyphotic deformity in Kümmell's disease through vertebral body screw fixation and intertransverse process grafting: A case report.

RATIONALE: Kümmell's disease, also well acknowledged as delayed posttraumatic vertebral body collapse, it is a rare condition which mainly occurs in elderly people more than 50 years old, with the thoracolumbar junction being mostly affected. PATIENT CONCERNS: In this research, we employed posterior short-segment screw fixation within the injured vertebral region, coupled with intertransverse process bone grafting, to address Kümmell's disease. A 57-year-old female was admitted to our institution with incapacitating back pain and obvious kyphotic deformity. DIAGNOSES: The diagnosis of Kummell disease was mainly depended on clinical symptoms and imaging examinations. INTERVENTIONS: In this research, we employed posterior short-segment screw fixation within the injured vertebral region, coupled with intertransverse process bone grafting, to address Kümmell's disease. OUTCOMES: The patient could walk independently with the help of a thoracolumbosacral orthosis brace on postoperative Day 2. No pains, kyphotic deformity and neurological deficits were observed during the 36 months of postoperative follow-up. These improvements can be visualized through postoperative magnetic resonance imaging and CT scans. Short-segment screw fixation provides short-term stability to the fracture site and accelerates fracture healing. Subsequently, the healed intervertebral and transverse process grafts offer long-term stability, a fact corroborated by postoperative CT scans. LESSONS: In summary, for Kümmell's disease patients exhibiting kyphotic deformity without neurological deficits or compression, posterior short-segment vertebral screw fixation with intertransverse process bone grafting stands as a viable alternative treatment approach.