Posterior vertebral column resection in spinal deformity: a systematic review

Biomechanical and clinical evaluation of PSO, modified PSO and VCR treating OVCF kyphosis: a finite element analysis

Objective

To confirm the effect of surgery on spinal column biomechanics and to provide theoretical support for the advantages and disadvantages of different surgical methods and their clinical efficacy.

Methods

33 continuous patients with no significant difference in risk factors related to the mechanical complications were enrolled in this retrospective study. Sagittal parameters were measured in the pre-, post-operative and following-up lateral radiograph of spine. An finite element (FE) model was created using CT scanning from a female volunteer with osteoporotic vertebral compression fracture (OVCF) with solely kyphosis. Pedicle subtraction osteotomy (PSO), vertebral column resection (VCR) and modified PSO(mPSO) for OVCF were simulated on FE model. Stress distribution and deformation of the FE model were measured.

Results

Clinical - All differences in preoperative spinal sagittal parameters were not statistically significant. mPSO showed it is superior to PSO and VCR in multiple postoperative and following-up spinal sagittal parameters. The operation duration and intraoperative blood loss of mPSO are less than the other two. For postoperative mechanical complications, no statistically significant differences were observed. Biomechanical - Six operating conditions (flexion, extension, left/right bending, left/right twisting) for each post-operative FE model have been examined. In most conditions, the displacement of mPSO is similar to that of PSO, with both larger than that of VCR. All the maximum equivalent stress on the vertebral body is within the safe range. The stress is mainly distributed on the T10 vertebral body and the fixed vertebral body L2, while the stress of VCR is greater than that of mPSO and PSO. The intervertebral disc pressure is highest in VCR, followed by PSO, and lowest in mPSO under all conditions. The maximum pressure on the intervertebral discs is located between T10 and T11.

Conclusion

The finite element analysis showed that mPSO has a similar spine stability to PSO, and possibly creates a better environment for bone-to-bone fusion and prevents adjacent segments degeneration. Combined with its less surgical risks, we believe that the modified pedicle subtraction osteotomy may be an appropriate strategy for indicated cases of OVCF.

Predictive Value of Bolster Supine X-Ray for the Correction of Segmental Deformity After Thoracolumbar Fusion Surgery

BACKGROUND AND OBJECTIVES

Assessment of thoracolumbar spine flexibility is crucial for determining which osteotomy to perform (posterior column osteotomy or 3-column osteotomy) to restore sagittal balance. Although preoperative bolster supine X-rays have been used to evaluate spine flexibility, their correlation with postoperative spinopelvic parameters has not been reported. We aimed to evaluate the predictive value of bolster X-ray for correcting sagittal deformities after thoracolumbar fusion surgery.

METHODS

We retrospectively evaluated patients who underwent bolster supine radiography before posterior thoracolumbar fusion. Demographic data, operative records, and radiographic parameters were also recorded. The segmental Cobb angle, defined as the angle between the upper endplate of the uppermost and lower endplates of the lowest instrumented vertebrae, was compared between bolster and postoperative X-ray to evaluate the correlation between them. The predictive value of bolster X-ray for postoperative deformity correction was measured using intraclass correlation coefficients (ICC).

RESULTS

Forty-two patients were included. The preoperative segmental Cobb angle (-1.4 ± 22.4) was significantly lower than the bolster segmental Cobb angle (23.2 ± 18.7, P < .001) and postoperative segmental Cobb angle (27.9 ± 22.3, P < .001); however, no significant difference was observed between the bolster and postoperative segmental Cobb angles ( P = .746). Bolster X-ray showed a very strong correlation with postoperative X-ray (r = 0.950, P < .001) for segmental Cobb angle. Bolster supine X-ray had good-to-excellent reliability for postoperative X-ray with an ICC of 0.913 (95% CI, 0.760-0.962, P < .001) for the segmental Cobb angle.

CONCLUSION

Bolster supine X-rays demonstrate good-to-excellent reliability with postoperative X-rays for segmental Cobb angles. These findings offer valuable insights into the selection of appropriate osteotomy techniques for clinical practice.

Complications and outcomes after three-column osteotomy: a 5-year follow-up

BACKGROUND

Three-column spinal osteotomies (3-CO) are powerful techniques used to correct spinal deformity. These surgeries are associated with an elevated risk of complications. While outcomes have been reported in the literature with 2 years follow-up, longer-term outcomes of three-column osteotomies remain understudied.

OBJECTIVES

This study aims to examine patient reported outcomes and complications for three-column osteotomies at 5 years.

STUDY DESIGN

Retrospective review of a prospectively collected spinal deformity cases database.

PATIENT SAMPLE

All consecutive adult patients at a single spine surgery center treated with either a pedicle subtraction osteotomy (PSO) or vertebral column resection (VCR) for spinal deformity, and with a minimum 5-year follow-up were included.

OUTCOME MEASURES

Visual-analog scale (VAS) for back pain score (0 to 10), Oswestry Disability Index (ODI) score (0 to 100), number of complications, revision rate, sagittal balance, lumbar lordosis at preoperative and at 5-year visit.

METHODS

Data was extracted from a prospectively collected spinal deformity surgery database continuously updated since 2002 with data from operative reports, patients' medical visit notes and patients' self-reported VAS and ODI questionnaires completed at each office visit. Radiographic measurements were performed on standing full-length spine radiographs taken at preop and 5-year visits. Descriptive statistics, comparison of means and proportions among groups, and a logistic regression analysis were conducted using the statistical software package SPSS version 28. Statistical significance was set at p<.05.

RESULTS

Of 127 consecutive adult patients with minimum of 5-year follow-up undergoing a 3-CO posterior spinal surgery for spinal deformity were identified and included in the study, 79 (62%) were treated with PSO, and 48 (38%) with VCR. Both PSO and VCR groups demonstrated significant improvements in VAS (PSO preop: 6.7, 5-year: 4.6, p<.001; VCR preop: 7.1, 5-year: 5.2, p<.001), and ODI (PSO preop: 52.9, 5-year: 45.4, p<.001; VCR preop: 57.5, 5-year 43.0, p<.001) that were maintained at 5 years. Major and minor complications occurring within 5 years were not statistically different between the PSO and VCR groups (major: 59.5% vs 56.3%, p=.85; minor: 45.6% vs 37.5%, p=.46). The rate of revision surgery within 5 years was 39.4% overall. Of the fifty patients requiring revision, 37.5% were for nonunion, 27.1% instrumentation failure, 14.6% proximal junctional kyphosis (PJK), 12.5% vertebral fracture, 6.3% motor weakness, and 2.1% infection. Improvements in lumbar lordosis were maintained at 5 years in both the PSO (29.9° vs 47.2°, p<.001) and VCR (34.6° vs 48.5°, p<.001) groups while sagittal balance maintained significant improvement in the VCR group (9.5 cm vs 6.3 cm, p=.008) but not the PSO (11.4 cm vs 9.3 cm, p=.065).

CONCLUSION

Patients undergoing three-column osteotomies had a major complication rate of 57.5% and a minor complication rate of 42.5% after 5 years. Improvements in lumbar lordosis were maintained at 5-year follow-up, but sagittal balance was only maintained in the VCR group. Despite these radiographic findings, both VCR and PSO groups maintained significant clinical improvements in both VAS and ODI scores at 5-year follow up.

Spinal cord injury in high-risk complex adult spinal deformity surgery: review of incidence and outcomes from the Scoli-RISK-1 study

STUDY DESIGN

Clinical case series.

OBJECTIVE

To describe the cause, treatment and outcome of 6 cases of perioperative spinal cord injury (SCI) in high-risk adult deformity surgery.

SETTING

Adult spinal deformity patients were enrolled in the multi-center Scoli-RISK-1 cohort study.

METHODS

A total of 272 patients who underwent complex adult deformity surgery were enrolled in the prospective, multi-center Scoli-RISK-1 cohort study. Clinical follow up data were available up to a maximum of 2 years after index surgery. Cases of perioperative SCI were identified and an extensive case review was performed.

RESULTS

Six individuals with SCI were identified from the Scoli-RISK-1 database (2.2%). Two cases occurred intraoperatively and four cases occurred postoperatively. The first case was an incomplete SCI due to a direct intraoperative insult and was treated postoperatively with Riluzole. The second SCI case was caused by a compression injury due to overcorrection of the deformity. Three cases of incomplete SCI occurred; one case of postoperative hematoma, one case of proximal junctional kyphosis (PJK) and one case of adjacent segment disc herniation. All cases of post-operative incomplete SCI were managed with revision decompression and resulted in excellent clinical recovery. One case of incomplete SCI resulted from infection and PJK. The patient's treatment was complicated by a delay in revision and the patient suffered persistent neurological deficits up to six weeks following the onset of SCI.

CONCLUSION

Despite the low incidence in high-risk adult deformity surgeries, perioperative SCI can result in devastating consequences. Thus, appropriate postoperative care, follow up and timely management of SCI are essential.

Modified pedicle subtraction osteotomy for osteoporotic vertebral compression fractures: a retrospective study of 104 patients

BACKGROUND

Osteoporotic vertebral compression fractures (OVCF) caused by osteoporosis is a common clinical fracture type. There are many surgical treatment options for OVCF, but there is a lack of comparison among different options. Therefore, we counted a total of 104 cases of OVCF operations with different surgical plans, followed up the patients, and compared the surgical outcome indications before, after and during the follow-up.

METHOD

104 patients who underwent posterior osteotomy (Modified PSO, SPO, PSO, VCR) and kyphosis correction surgery at our hospital between April 2006 and August 2021 with a minimum follow-up period of 24 months were included. All cases were injuries induced by a fall incurred while standing or lifting heavy objects without high-energy trauma. The mean CT value was 71 HU, which was below 110 HU, indicating severe osteoporosis. The indications for surgery included gait disturbance due to severe pain with pseudarthrosis, increased kyphotic angle, and progressive neurological symptoms. Pre- and postoperative CL, TLK, TK, PrTK, TKmax, GK, LL, PI, SS, PT, SVA, TPA, were investigated radiologically. Additionally, We evaluated estimated blood loss, surgical time and perioperative symptom.

RESULT

The results show, after operation, TLK (37.32 ± 10.61° vs. 11.01 ± 8.06°, P < 0.001), TK (35.42 ± 17.64° vs. 25.62 ± 12.24°, P < 0.001), TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001), SVA (44.91 ± 48.67 vs. 23.52 ± 30.21, P = 0.013), CL (20.23 ± 13.21° vs. 11.45 ± 9.85°, P = 0.024) and TPA (27.44 ± 12.76° vs. 13.91 ± 9.24°, P = 0.009) were improved significantly in modified Pedicle subtraction osteotomy (mPSO) after operation. During follow-up, TLK (37.32 ± 10.61° vs. 13.88 ± 10.02°, P < 0.001) and TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001) were improved significantly in Modified PSO group. In additon, estimated blood loss (790.0 ± 552.2 ml vs. 987.0 ± 638.5 ml, P = 0.038), time of operation (244.1 ± 63.0 min vs. 292.4 ± 87.6 min, P = 0.025) were favorable in Modified PSO group compared to control group.

CONCLUSION

To conclude, mPSO could acquire a favorable degree of kyphosis correction as well as fewer follow-up complications. Compared with other surgical methods, it also has the advantages of less surgical trauma and shorter operation time. It can be an effective solution for the treatment of OVCF.

Surgical management of omega deformity in a patient with neurofibromatosis type 1: a case report

PURPOSE

To describe the surgical treatment in a patient with a partial omega deformity in the thoracic spine with neurofibromatosis type 1.

METHODS

The patient was a 55-year-old man with an omega deformity, which is defined as a curvature in which the end vertebra is positioned at the level of, above, or below the apical vertebra (i.e., a horizontal line bisecting it). We performed halo gravity traction (HGT) for 7 weeks, followed by posterior spinal instrumented nearly equal in situ fusion from T2-L5 with three femoral head allografts and a local bone autograft. We avoided reconstruction of the thoracic anterior spine because of his severe pulmonary dysfunction.

RESULTS

HGT improved the % vital capacity from 32.5 to 43.5%, and improved the Cobb angle of the kyphosis from > 180° before traction to 144° after traction. The Cobb angle of kyphosis and scoliosis changed from > 180° preoperatively to 155° and 146°, respectively, postoperatively, and 167° and 156°, respectively, at final follow-up. His postoperative respiratory function deteriorated transiently due to bilateral pleural effusions and compressive atelectasis, which was successfully treated with a frequent change of position and nasal high flow for 1 week. At final follow-up, his pulmonary function improved from 0.86 to 1.04 L in VC, and from 32.5 to 37.9% in %VC. However, there was no overall improvement in preoperative distress following surgery, although his modified Borg scale improved from 3 preoperatively to 0.5 postoperatively. One month after discharge, he felt worsening respiratory distress (SpO2:75%) and was readmitted for pulmonary hypertension for 2 months. He was improved by non-invasive positive pressure ventilation (biphasic positive airway pressure) for 1 week, medication and daily lung physiotherapy. Thereafter, he has been receiving permanent daytime (0.5 L/min) and nighttime (2 L/min) oxygen therapy at home. A solid arthrodesis through the fusion area was confirmed on computed tomography. However, the kyphosis correction loss was 12° (i.e., 155°-167°), while the scoliosis correction loss was 10° (i.e., 146°-156°) at 2 years of recovery.

CONCLUSIONS

We suggest that nearly equal in situ fusion is a valid option for preventing further deformity deterioration and avoiding fatal complications.

Posterior vertebral column resection: Exploring practical uses in clinical settings

Background

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.

Methods

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.

Results

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.

Conclusion

PVCR is an effective method for correcting severe spinal deformities and can be used to correct curvature in different patient groups.

Level of Evidence

Level 3.

Improvement of Pulmonary Function and Reconstructed 3-Dimensional Lung Volume After Halo-Pelvic Traction Combined With Posterior Correction for Severe Rigid Spinal Scoliosis: A Multicenter Study

BACKGROUND AND OBJECTIVES

Severe rigid spinal scoliosis (SRSS) leads to severe restrictive ventilation dysfunction. Currently, the reports about the influence of preoperative halo-pelvic traction (HPT) combined with correction surgery on pulmonary function in patients with SRSS were relatively few. This study aims to investigate (1) the influence of preoperative HPT on lung volume and pulmonary function, (2) the further influence of the following correction surgery on lung volume and pulmonary function, and (3) the relationship among deformity correction, pulmonary function test outcomes, and computed tomography-based lung volume.

METHODS

A total of 135 patients with SRSS who underwent preoperative HPT and followed low-grade osteotomy correction surgery were reviewed. Spinal parameters, including proximal thoracic curve, main thoracic curve (MTC), lumbar curve, coronal balance, thoracic kyphosis, lumbar lordosis, sagittal vertical axis, pulmonary function test outcomes (forced vital capacity [FVC], the percentage of predicted forced vital capacity [FVC%], forced expiratory volume in 1 second [FEV1], total lung capacity [TLC]), and lung volume (Vin), were analyzed before, after HPT and at the final follow-up, respectively.

RESULTS

The mean FVC, FVC%, FEV1, and TLC increased from 1.67 L, 51.13%, 1.47 L, and 2.37 L to 1.95 L, 64.35%, 1.75 L, and 2.78 L, respectively, after HPT and further improved to 2.22 L, 72.14%, 1.95 L, and 3.15 L, respectively, at the final follow-up. The mean Vin increased from 1.98 L to 2.42 L after traction and further increased to 2.76 L at the final follow-up. The variation of MTC was correlated with the improvement of FVC (r = 0.429, P = .026), FVC% (r = 0.401, P = .038), FEV1 (r = 0.340, P = .043), and TLC (r = 0.421, P = .029) and the variation of Vin (r = 0.425, P = .015) before HPT and after surgery.

CONCLUSION

Preoperative HPT can improve preoperative pulmonary function and enhance the preoperative lung volume. There were significant correlations among the variations of MTC, pulmonary function indexes, and lung volume before HPT and after surgery in patients with SRSS.

The contribution of preoperative balanced halo-pelvic traction to severe rigid spinal deformity correction

PURPOSE

The aim of this study was to assess the clinical efficacy of balanced halo-pelvic traction (HPT) and evaluate its contribution to the correction surgery in treating adult severe rigid spinal deformity.

METHODS

One hundred and eight adult patients with severe rigid spinal deformity who underwent preoperative HPT and correction surgery were reviewed. The main coronal curve, segmental kyphotic angle, coronal balance (CB), sagittal balance (SVA), and the length of spine were measured before HPT, after HPT, post-operatively, and at final follow-up. The HPT contribution rates to deformity correction were calculated.

RESULTS

The pre-HPT main coronal curve was 103.4 ± 10.6°, improved to 61.0 ± 13.4° after traction and further improved to 44.2 ± 10.2° after surgical correction, and maintained at 50.3 ± 9.9° at final follow-up. CB started at 4.2 ± 4.8 cm, improved to 2.1 ± 2.5 cm after HPT, 0.8 ± 1.2 cm after operation, and 0.7 ± 0.9 cm at final follow-up. The pre-HPT sagittal segmental kyphotic angle was 67.3 ± 17.7°, was then improved to 42.2 ± 27.5° after traction and further improved to 34.9 ± 10.2° after surgery, and maintained at 35.4 ± 10.4° at final follow-up. The length of spine improved from 35.9 ± 5.9 to 42.6 ± 6.0 cm via HPT, reached up to 45.0 ± 6.0 cm after operation, and maintained at 44.3 ± 5.2 cm at final follow-up.

CONCLUSION

HPT is effective for the treatment of severe rigid spinal deformity. Balanced HPT can dramatically improve coronal and sagittal deformity as well as spinal length before corrective surgery.

Intraoperative Neurophysiological Monitoring Alerts During Three-Column Osteotomy: Incidence and Risk Factors

PRUPOSE

To analyze the incidence and risk factors of intraoperative neurophysiological monitoring (IONM) alerts in patients undergoing three-column osteotomy.

METHODS

A total of 551 patients (340 males and 211 females) with an average age of 31.9 years undergoing posterior 3-column osteotomy were retrospectively reviewed. The coronal Cobb angle of main curve and sagittal global kyphosis were measured on preoperative standing whole spinal x-rays. The Frankel scores at preoperation, postoperation, and the last follow-up were recorded and applied for assessment of neurologic status. Surgical procedures and other factors associated with IONM alerts were analyzed.

RESULTS

A total of 98 (17.8%) IONM alerts were reported during surgery, including 82 somatosensory evoked potential alerts and 91 motor evoked potential alerts. Positive wake-up test was revealed in 57 patients (10.3%) even after prompt managements, and new neurologic deficits were observed in 50 patients (9.1%) at immediate postoperation. Of the 50 patients with new neurologic deficits at postoperation, the Frankel scores were A in 5 patients, B in 4, C in 9, and D in 32. The χ 2 test showed that patients with congenital deformities, global kyphosis >90°, vertebral column resection procedure, cervicothoracic/thoracic osteotomy, blood loss >3,000 mL, and preoperative neurologic deficit were at a higher risk of IONM alerts.

CONCLUSIONS

The incidence of IONM alerts in patients undergoing 3-column osteotomy was 17.8%. Congenital deformities, global kyphosis >90°, vertebral column resection, cervicothoracic/thoracic osteotomy, blood loss >3,000 mL, and preoperative neurologic deficit indicated high risk of IONM alerts.

Multi-rod posterior correction only with halo-femoral traction for the management of adult neuromuscular scoliosis (> 100°) with severe pelvic obliquity: a minimum 5-year follow-up

BACKGROUND

Many patients with neuromuscular scoliosis (NMS) experience a variety of difficult medical problems that aggravate the development effects of progressive scoliosis and pelvic obliquity (PO). The objective of the current study was to assess the safety and effectiveness of multi-rod posterior correction only (MRPCO) with halo-femoral traction (HFT) for the management of adult NMS (> 100°) with severe PO.

METHODS

From 2012 to 2017, 13 adult patients who suffered from NMS (> 100°) with severe PO underwent MRPCO with HFT. The radiography parameters in a sitting position, such as the coronal Cobb angle of the main curve, the PO and the trunk shift (TS), were measured at the preoperative, postoperative and final follow-up stages. The preoperative and final follow-up assessment of the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) was taken.

RESULTS

The average follow-up span was 68.15 ± 6.78 months. There was decreased postoperative coronal Cobb angle with an average mean of 125.24° ± 11.78° to 47.55° ± 12.10°, with a correction rate of 62.43%; the PO was reduced to 6.25° ± 1.63° from 36.93° ± 4.25° with a correction rate of 83.07%; the TS was reduced to 2.41 cm ± 1.40 cm from 9.19 cm ± 3.07 cm. There was significant improvement in all parameters compared to the preoperative data. The VAS score reduced from 4.77 ± 0.93 to 0.69 ± 0.75, and the ODI score reduced from 65.38 ± 16.80 to 28.62 ± 12.29 at the final follow-up.

CONCLUSIONS

Treatment of adult NMS (> 100°) with severe PO could be safe and effective with MRPCO with HFT. In order to obtain the optimum sitting balance, this could reduce the prevalence of complications and rectify the curvature and the correction of PO.

Posterior-based Osteotomies for Deformity Correction

Posterior-based osteotomies are crucial to the restoration of lordosis in adult spinal deformity. Posterior-column osteotomies are suited for patients with an unfused anterior column and non-focal sagittal deformity requiring modest correction in lordosis. When performed on multiple levels, posterior-column osteotomy may provide significant harmonious correction in patients who require more extensive correction. Pedicle subtraction osteotomy and vertebral column resection are appropriate for patients with a fused anterior column and more severe deformity, particularly focal and/or multiplanar deformity. The power of pedicle subtraction osteotomy and vertebral column resection to provide greater correction and to address multiplanar deformity comes at the cost of higher complication rates than posterior-column osteotomy.

Correction of severe adult idiopathic scoliosis posteriorly with skipped pedicle screw instrumentation and rod augmentation

BACKGROUND

Although it is challenging to correct severe adult idiopathic scoliosis (ADIS) deformities, optimal results can be achieved by multiple asymmetric Ponte osteotomies with lower surgical risks. Skipping the apical instrumentation and using multiple rods and connectors may further facilitate the procedure. We named this method as "modular correction technique" (MCT).

METHODS

Sixty-two patients with severe ADIS who were treated with MCT were recruited into this study, and retrospectively evaluated. Radiographic and functional outcomes as well as pulmonary functions were examined preoperatively and at last follow-up. Main radiologic parameters were related to Cobb angles, coronal, sagittal, and shoulder balance. Scoliosis Research Society-22 questionnaire and the Oswestry Disability Index were used to evaluate clinical outcomes.

RESULTS

Average age of the patients was 41.3 years (range: 23-65). Thirty-nine of the patients were female and 23 of them were male. Coronal Cobb angle of the main curve, shoulder balance, coronal, and sagittal balance significantly improved after the surgery. Forced vital capacity and forced expiratory volume in the first second were mildly improved after the surgery, however the improvement was not statistically significant. Postoperative clinical outcome scores improved significantly.

CONCLUSION

MCT can be performed with low risk of complications and relatively low operation time and blood loss. It facilitates rod insertion and correction maneuvers. Radiologic, especially coronal balance, and functional outcomes can be improved with minimal morbidity while deterioration of pulmonary function is prevented. This technique is useful in severe but relatively flexible ADIS deformities.

Long-term Outcomes of Posterior Multilevel Crack Osteotomy: Revisional Surgery for Scoliosis With a Fusion Mass

OBJECTIVE

Osteotomies are required for the mobilization of spinal segments in patients with revisional scoliosis surgery with a fusion mass; however, only a few techniques have shown efficacy and safety, and their mid- and long-term outcomes remain unelucidated. This study aimed to analyze long-term outcomes of the posterior multilevel crack osteotomy (PMCO) technique for revisional surgery for scoliosis with a fusion mass.

METHODS

Data from 18 patients who underwent revisional scoliosis surgery using PMCO between 2009 and 2015 and had more than 5-year follow-up were retrospectively reviewed. The Cobb angle and coronal and sagittal balance parameters were examined preoperatively, postoperatively, and during the final follow-up. Perioperative parameters and complications were also assessed.

RESULTS

Preoperative and postoperative Cobb angles were 60.5° and 29.9°, respectively (p < 0.001); this improvement was maintained until the final follow-up (33.4°, p = 0.058). The difference in preoperative and postoperative coronal balance was statistically significant (15.9 mm and 9.2 mm, respectively; p < 0.001); this was maintained until the final follow-up (p = 0.071). There was no change in sagittal balance parameters over the 3 measurement periods. Only 1 patient showed PMCO-related motor weakness, but he spontaneously recovered 3 months after postsurgery. Pseudarthrosis was not observed during the follow-up period.

CONCLUSION

Incomplete osteotomy using PMCO provided satisfactory deformity correction without severe complications during revisional surgery for scoliosis with a fusion mass. It may be a less invasive procedure that maintains cortical continuity, preserves soft tissues, and provides sufficient mobility for the correction of spinal segments.

Modified Bone-Disc-Bone Osteotomy for Spinal Kyphosis: A Retrospective Clinical Study with 2-Year Follow-Up

OBJECTIVE

To determine the efficacy of modified bone-disc-bone osteotomy to treat spinal kyphosis.

METHODS

Between January 2018 and December 2022, 20 patients underwent modified bone-disc-bone osteotomy surgery for spinal kyphosis. Radiologic parameters pelvic incidence, pelvic tilt, sagittal vertical axis, and kyphotic Cobb angle were measured and compared. Oswestry Disability Index, visual analog scale, and general complications were recorded to evaluate clinical outcomes.

RESULTS

All 20 patients completed 24 months of postoperative follow-up. Mean kyphotic Cobb angle correction was from 40.2 ± 6.8° to 8.9 ± 4.1° immediately after surgery to 9.8 ± 4.8° at 24 months postoperatively. Average surgical time was 277 minutes (range, 180-490 minutes). Mean intraoperative blood loss was 1215 mL (range, 800-2500 mL). Sagittal vertical axis was improved from 4.2 cm (range, 1-5.8 cm) preoperatively to 1.1 cm (range, 0-2 cm) at final follow-up (P < 0.05). Pelvic tilt was reduced from 27.6 ± 4.1 preoperatively to 14.9 ± 4.4 postoperatively (P < 0.05). Visual analog scale decreased from 5.8 ± 1.1 preoperatively to 1 ± 0.6 at final follow-up (P < 0.05). Oswestry Disability Index changed from 28.7 ± 2.7% preoperatively to 9.4 ± 1.8% at final follow-up. Bony fusion was achieved at 12 months postoperatively in all patients. All patients experienced significant improvement in clinical symptoms and neurological function at final follow-up.

CONCLUSIONS

Modified bone-disc-bone osteotomy surgery is an effective and safe method for treatment of spinal kyphosis.

Paraparesis and congenital severe hyperkyphosis in Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome: A rare deformity management during the Sars-Cov-2 pandemic

Introduction

Mayer-Rokitansky-Küster-Hauser syndrome (MRKH) syndrome can be classified into two types: type I (isolated) without extragenital abnormalities; type II (associated) with the presence of extragenital dimorphisms. Skeletal abnormalities are the second most frequent extragenital manifestations.

Research question

Association between MRKH and congenital scoliosis has been described; on the contrary, hyperkyphosis is very rare and sparsely described in the medical literature. Here we report our experience in the management of thoracolumbar hyperkyphosis in 16-year-old patient diagnosed with MRKH syndrome with an acute neurological impairment due to T11-T12 disc herniation.

Material and methods

Clinical and radiological images of the case were retrieved from the medical notes, operative records and imaging system.

Results

Posterior surgical correction was proposed to treat the severe spinal deformity; however, surgery was delayed because of SARS-CoV2 pandemic outbreak. During the pandemic, the patient had a major clinical and radiological deterioration with development of paraparesis. Complete clinical resolution of the paraparesis and restoration of balance was achieved with a two stage surgical approach, with a first anterior stage followed by a delayed posterior approach aimed at deformity correction.

Discussion

Congenital kyphosis are rare deformities that can progress rapidly leading to severe neurological deficits and worsening of the deformity. When patient has neurological deficit the surgical strategy to address the neurological problem first and plan the more complex and demanding corrective surgery remains a valid strategy that must be consider.

Conclusion

This is the first reported case of hyperkyphosis in Mayer-Rokitansky-Küster-Hauser syndrome (MRKH) syndrome surgically treated.

Severe kyphoscoliosis correction utilizing sublaminar bands in the setting of a vertebral column resection: a unique technical report

PURPOSE

Severe kyphoscoliosis produces combined coronal and sagittal imbalance, a challenging presentation of Adult Spinal Deformity (ASD). Vertebral column resection (VCR) provides three-dimensional correction typically reserved for severe and/or fixed deformities. The challenge of a VCR is to stabilize the spinal column during incremental reduction maneuvers to correct the deformity. We describe novel use of sub-laminar bands with a temporary pivoting rod construct to achieve coronal and sagittal correction in one reductive maneuver.

METHODS

All available notes, imaging, and reports were summarized for inclusion.

RESULTS

A 67-year-old male presented severe, progressive thoracolumbar kyphoscoliosis, subsequent back pain, and difficulty in ambulating. Given the progression, surgical intervention was undertaken. The patient underwent an L3 VCR followed by instrumentation from T2 to pelvis. Kyphoscoliosis correction was performed via a single reduction maneuver using novel pivoting-rod construct and sub-laminar bands followed by quad-rod construct placement. Fresh, frozen, femoral head allograft, and BMP were utilized. The patient was placed in a Jewett brace for 6 weeks postoperatively and recovered. His condition remains optimized at three-year follow-up.

CONCLUSION

Correcting three-dimensional deformities can require vertebral column resection and pose risk during correction. We propose a sub-laminar band with a pivot-rod construct as a safe, effective technique, limiting the number of reduction maneuvers.

Sequential correction using satellite rod for the treatment of severe rigid spinal deformity: a retrospective study of 19 cases

OBJECTIVES

The purpose of this study was to evaluate the effectiveness of sequential correction using satellite rod in patients with severe rigid spinal deformity undergoing posterior-only PVCR.

METHODS

19 patients with severe rigid spinal deformity who underwent PVCR at our center from January 2014 to December 2019 were reviewed. Radiographic measurements, including major coronal Cobb angle, kyphotic curve angle, coronal and sagittal balance were measured. Clinical results were noted, including the SRS-22 questionnaire, the Oswestry Disability Index score, and complications.

RESULTS

Total 19 patients were followed at least 2 years. The mean coronal Cobb angle decreased from 122.7° ± 13.17° to 57.89° ± 8.65° postoperatively, and to 58.42° ± 8.98° at final follow-up. Correction rate is 52.8%. The kyphotic curve angle improved from 102.2° ± 17.05° preoperatively to 39.68° ± 13.67° postoperatively, and to 37.74° ± 12.14° at final follow-up. Correction rate is 61.2%. Compared to preoperative results, apex vertebral translation, ODI and SRS-22 were significantly improved at the final follow-up.

CONCLUSIONS

For patients with severe rigid spinal deformities, sequential correction with an auxiliary satellite rod can effectively reduce surgical difficulty and improve correction rate.

Vertebral column resection (VCR) at the subapical vertebra for correction of angular kyphosis associated with neurofibromatosis type 1(NF1): a case report

PURPOSE

To describe the process and outcome of vertebral column resection (VCR) at the subapical vertebra for correction of angular kyphosis associated with neurofibromatosis type 1(NF1).

METHODS

A review and summary of the medical history, radiographs, operative procedure, and complications of a 16-year-old male presenting with severe angular kyphosis associated with NF1 with dyspnea.

RESULTS

A 16-year-old male presented with severe angular kyphosis associated with NF1 with dyspnea. Preoperative radiographs demonstrated multiple vertebrae were rotated in the vicinity of the apical vertebra, with a wedge-shaped deformity, dysplasia, T10-T12 kyphotic angle of 160°, and T2-L2 kyphotic angle of 95°. VCR at the L1 vertebra (distal end of the apical vertebra) with bone grafting and internal fixation was performed. Postoperative imaging revealed that the T2-L2 Cobb angle was 20°, denoting a correction rate of 79%. The patient's height increased from 130 to 150 cm. The position of internal fixation was not displaced, and the correction angle was maintained at 2-year follow-up.

CONCLUSIONS

The novel strategy of performing VCR at the subapical vertebra, with posterior displacement of the distal end, and remodeling of the spinal canal is potentially a safe and efficacious option to correct sharp angular kyphosis.

Adult Spinal Deformity: A Comprehensive Review of Current Advances and Future Directions

Owing to rapidly changing global demographics, adult spinal deformity (ASD) now accounts for a significant proportion of the Global Burden of Disease. Sagittal imbalance caused by age-related degenerative changes leads to back pain, neurological deficits, and deformity, which negatively affect the health-related quality of life (HRQoL) of patients. Along with the recognized regional, global, and sagittal spinopelvic parameters, poor paraspinal muscle quality has recently been acknowledged as a key determinant of the clinical outcomes of ASD. Although the Scoliosis Research Society-Schwab ASD classification system incorporates the radiological factors related to HRQoL, it cannot accurately predict the mechanical complications. With the rapid advances in surgical techniques, many surgical options for ASD have been developed, ranging from minimally invasive surgery to osteotomies. Therefore, structured patient-specific management is important in surgical decision-making, selecting the proper surgical technique, and to prevent serious complications in patients with ASD. Moreover, utilizing the latest technologies such as robotic-assisted surgery and machine learning, should help in minimizing the surgical risks and complications in the future.

Posterior vertebral column resection for pediatric rigid spinal deformity

INTRODUCTION

Surgery for pediatric spinal deformity may involve vertebral osteotomies in complex cases. Vertebral column resection (VCR) is the most technically demanding procedure, with the severest morbidity. It can use a double anterior and posterior approach (APVCR), though a single posterior approach (PVCR) is gaining in popularity.

HYPOTHESIS

PVCR provides effective correction with acceptable morbidity in children.

METHOD

A single-center retrospective series included spinal deformities treated by PVCR. Surgical data and global pelvic-spinal balance parameters were analyzed.

RESULTS

Sixteen PVCRs were performed in 13 patients, with a mean age of 14.1±2.8 years. Mean operative time was 411±54minutes. Mean preoperative rigid principal Cobb angle was 74.3°. Mean correction was 64.3% postoperatively, without significant correction loss at last follow-up. Mean blood loss was 941±221ml. The cell-saver enabled 92.3% autologous transfusions, with 53.4% homologous transfusions. Transient monoplegia and permanent psoas deficit were observed during the postoperative period. Radiologic follow-up found 4 non-unions requiring revision.

CONCLUSION

PVCR provided major correction of rigid spinal deformity in children. Complications mainly comprised mechanical or neurological incidents.

LEVEL OF EVIDENCE

IV, non-comparative cohort study.

Posterior Vertebral Column Resection (pVCR) for Severe Thoracolumbar Kyphosis in Patients With Achondroplasia

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

We aimed to evaluate the safety and validity of posterior vertebral column resection (pVCR) for severe thoracolumbar kyphosis (TLK) in the achondroplasia (ACH) patients.

METHODS

Seven ACH patients (male: female = 6:1) who underwent pVCR procedures due to severe TLK from December 2008 to December 2017 in the authors' hospital were included in this retrospective study. Their mean follow-up duration was 67 ± 35 months. Their clinical characteristics, radiologic characteristics, surgical characteristics and surgical complications were reviewed.

RESULTS

A total of 8 vertebrae were removed with an average of 5 ± 2 levels of decompression and 9 ± 2 segments instrumented. The mean correction rates of TLKs and the main curves were 73 ± 15% and 87 ± 6%, respectively. Five patients (71%) had preoperative neurological symptoms with a mean Japanese Orthopedic Association (JOA) score of 8 ± 3 points. Their neurological functions were all improved, with a recovery rate of 78 ± 32% for the JOA score at the last follow-up. Four patients (57%) suffered from surgical complications, including rod breakages (43%), neurological complications (28%), dural tears (14%), cerebrospinal fluid leaks (14%) and proximal junction kyphosis (14%).

CONCLUSIONS

pVCR can offer a good correction for TLK and improve neurological function with extensive laminectomies in ACH patients. But the morbidity of surgical complications is relatively high. Therefore, it is a reserved surgical option for severe TLK in ACH patients by experienced spinal surgeons, especially with apical markedly hypoplastic vertebrae.

Posterior Vertebral Column Resection for Severe Spinal Deformity Correction: Comparison of Pediatric, Adolescent, and Adult Groups

We compared the pre-, intra-, and postoperative characteristics among three groups of patients who underwent posterior vertebral column resection (PVCR) to clarify age-related characteristics and to guide patient management, surgical planning, and complication avoiding. We compared and analyzed the etiology, surgical events, outcomes, and complications among pediatric, adolescent, and adult patients who underwent PVCR in a single-center database retrospectively. Patients were categorized into pediatric (0–12 yr), adolescent (13–19 yr), and adult (>20 yr) cohorts. Demographics, surgical events, clinical and radiographic results, and major complications were compared between groups. A total of 87 patients with a mean follow-up 42 (24–96) months were identified. Pediatric group (14) had a high frequency of congenital vertebral and cardiac abnormal, adolescents (47) presented more intracanal malformations, and idiopathic was common in the adult group (26). Although pediatric patients had shorter fusion levels than adolescent and adult, their mean resected vertebrae (1.91), percentage of blood loss (estimated blood loss per total blood volume) (201.9%), and operative time were much higher. The coronal/sagittal correction rate was significantly higher in the pediatric group (73.6%/72.3%). Overall, surgical complications were more frequent in adults, particularly neuromonitoring alert and implant failure. However, more severe complications were noted in younger patients. For pediatric patients with PVCR, poor physiological conditions and frequent comorbidities indicated cautious patient selection and sufficient preoperative preparation. The higher correction rate may be due to the excellent compliance of the spinal cord. For adult patients, preoperative traction and adjusting the tension of the spinal cord during surgery could contribute to neurological safety.

Closing-opening wedge osteotomy for the treatment of congenital kyphosis in children

BACKGROUND

To evaluate the safety and effectiveness of posterior closed-open wedge osteotomy for treatment of congenital kyphosis in children.

METHODS

Imaging and clinical data from January 2010 to December 2019 of posterior closed-open wedge osteotomy of congenital kyphosis with at least 2-year follow up was analyzed retrospectively. Perioperative indicators such as operation time, osteotomy site, osteotomy method and occurrence of complications, and imaging indicators were observed. The 3D printed models were used to measure the expanded distance of anterior edge vertebra and closed length of spinal canal line. The clinical effect was evaluated through SRS-22 questionnaires.

RESULTS

There were 15 CK patients in this study. The osteotomy segments and details are as follows: 1 case each for T6-9 and L2, 2 cases at T11, 3 cases at T12, and 6 cases at L1. The average operation time was 314 min, the average blood loss was 970 mL, the average fusion range was 6.3 segments, and the average time of follow up was 70.5 months. The Cobb angle of local kyphosis was corrected from 65.6 ± 18.8° to 11.3 ± 7.1°(p < .001). The range of kyphosis correction was 40-90°, and average correction rate was 83.2% (67.7-95.7%). The correction was stable in follow-up, and the kyphotic angle was 11.0 ± 7.6 (p = .68). The preoperative SVA was 31.5 ± 21.8 mm, and the postoperative recovery was 18.0 ± 15.5, while the last follow-up was 9.1 ± 7.9. The p values were 0.02 and 0.07 respectively. By using 3D printed models, the expanded distance of anterior edge vertebra and closed length of spinal canal line were 14.5 ± 7.5 mm and 24.5 ± 8.0 mm respectively. Self-image and satisfaction in SRS-22 improved significantly. There was no recurrence of deformity and junctional kyphosis.

CONCLUSIONS

The posterior closing-opening wedge osteotom for treatment of congenital kyphosis in children is satisfactory, if selected appropriately. During the longitudinal follow-up, the patients could achieve solid fusion and the correction could be well maintained.Evidence of Confidence: IVa.

The Reliability of Computer-Assisted Three-Dimensional Surgical Simulation of Posterior Osteotomies in Thoracolumbar Kyphosis Secondary to Ankylosing Spondylitis Patients

Objectives. The study was aimed at investigating the reliability of computer-assisted three-dimensional surgical simulation (CA3DSS) of posterior osteotomies in thoracolumbar kyphosis secondary to ankylosing spondylitis (TLKAS) patients. Methods. Eligible TLKAS patients who underwent posterior correction surgery with posterior osteotomies were consecutively included. Simulated posterior osteotomies were performed in Mimics and 3-Matic Medical software. Coronal and sagittal angle and alignment parameters were measured in preoperative full-length X-ray, preoperative original 3D spine (Pre-OS), simulated 3D spine (SS), and postoperative original 3D spine (Post-OS). Reliability was tested by both intraclass correlation coefficients (ICCs) and Bland-Altman analysis. Results. A total of 30 TLKAS patients were included. Excellent consistency of radiological parameters was shown between preoperative X-ray and Pre-OS model. In SS and Post-OS models, excellent reliabilities were shown in global kyphosis (ICC 0.832, 95% CI 0.677-0.916), thoracic kyphosis (ICC 0.773, 95% CI 0.577-0.885), and lumbar lordosis (ICC 0.896, 95% CI 0.794-0.949) and good reliabilities were exhibited in the main curve (ICC 0.680, 95% CI 0.428-0.834) and sagittal vertical axis (ICC 0.619, 95% CI 0.338-0.798). ICCs of correction angle achieved by pedicle subtraction osteotomy (PSO) was 0.754 (95% CI 0.487-0.892), and that of posterior column osteotomies (PCO) was 0.703 (95% CI 0.511-0.829). Bland-Altman analysis also showed good agreement for both Cobb angle and distance measurements in Pre-OS and SS models, and good reliabilities were shown in PCO and PSO in real spine and SS models. Conclusions. CA3DSS can provide an accurate measurement, and it is a reliable and effective method to conduct proper simulation for correction surgery with posterior osteotomies in TLKAS patients. This trial is registered with Chinese Clinical Trial Registry ChiCTR2100053808.

Retrospective analysis of deformed complex vertebral osteotomy in children with severe thoracic post-tubercular angular kyphosis

Background

Many surgical options have been described to manage post-tubercular kyphosis, but the standard approach for treating severe post-tubercular angular kyphosis in children has not been established yet. The present study was performed to evaluate the safety and efficacy of deformed complex vertebral osteotomy (DCVO) for the treatment of severe thoracic post-tubercular angular kyphosis (> 70°) in children.

Methods

Deformed complex vertebrae indicated that multiple deformed and fused vertebrae were usually involved with two or more vertebral bodies and the partial or total fusion of many segments' facet joints and intervertebral discs. Thus, DCVO indicated that a wider posterior wedge-shaped and three-column osteotomy was performed within deformed complex vertebrae to correct a more extensive range of angles. From 2010 to 2017, 15 children who suffered from severe thoracic post-tubercular angular kyphosis underwent DCVO. Deformed complex vertebrae involved two vertebral bodies in 9 patients and three vertebral bodies in 6 patients. The Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) were assessed preoperatively and at the final follow up. This was a retrospective study analysing the outcome after grade 4/5 spinal osteotomies in deformed complex vertebrae.

Results

The mean duration of surgery was 239 ± 37.81 min. The average period of follow-up was 31.6 ± 6.98 months. The preoperative mean kyphosis of deformed complex vertebrae was 83.39° ± 9.04°; the mean thoracic kyphosis (TK) and lumbar lordosis (LL) were 81.09° ± 8.51° and 80.51° ± 7.64°, respectively; the mean sagittal vertical axis (SVA) was 3.83 cm ± 1.43 cm. The postoperative mean kyphosis of deformed complex vertebrae was reduced to 19.98° ± 2.47° (P < 0.001) with a mean kyphosis correction of 63.41°; at the final follow up, it was 18.4° ± 2.29° (P < 0.001) without obvious loss of correction. The postoperative mean TK, LL, and SVA were reduced to 24.05° ± 3.84°, 46.9° ± 3.53°, and 0.6 cm ± 0.34 cm, respectively (P < 0.001 for all); and there was no obvious loss of sagittal alignment and balance at the final follow up (p = 0.982, p = 0.604, p = 0.754). Complicated with neural dysfunction preoperatively, 5 Frankel's grade D cases showed complete neurological recovery at final follow up. VAS score reduced from 3.6 ± 1.18 to 0.87 ± 0.64 (P < 0.001); and ODI score reduced from 22.21 ± 6.93 to 5.02 ± 2.6 (P < 0.001) at the final follow up.

Conclusions

DCVO was an individualized osteotomy for treating severe thoracic post-tubercular angular kyphosis in children and could be safe and effective in reducing the incidence of complications and significantly improving kyphosis correction.

Apical region correction and global balance: a 3-rods surgical strategy for the treatment of severe and rigid scoliosis

Background

The treatment of severe and rigid scoliosis is challenging. We developed a surgical strategy for severe and rigid scoliosis since 2014. This study aimed to retrospectively analyze the safety and efficacy of apical region correction and global balance with 3 rods as a surgical strategy for the treatment of severe and rigid scoliosis.

Methods

A retrospective study was performed for patients with severe and rigid scoliosis who underwent one-stage posterior corrective operation using the apical region correction and global balance with 3 rods surgical strategy between February 2014 and April 2020. The inclusion criteria were as follows: [1] Cobb angle > 90°; [2] flexibility < 30%; [3] a minimum 2-year follow-up. Patients were excluded if they had a history of traction or spinal surgery. Coronal and sagittal parameters, including Cobb angle, flexibility, apex vertebra translation, trunk shift (TS), thoracic kyphosis, lumbar lordosis, and sagittal vertical axis (SVA) were measured preoperatively, postoperatively and at the final follow-up. The Scoliosis Research Society 22-item questionnaire was administered preoperatively and at the final follow-up. During the operation, one slightly-bent short rod was placed into the concave side of apical region and correction was achieved by rod-rotation and distraction. Two pre-bent long rods were placed into both sides of the scoliosis and global balance was improved by leveling the proximal thoracic vertebrae and distal lumbar vertebrae.

Results

A total of 41 patients were included, with an average age of 20 years (range, 12–49 years) and follow-up of 34 months (range, 24–58 months). Postoperative correction rate was 53% for scoliosis. There were 14 patients with normal kyphosis before surgery, and 28 patients with normal kyphosis at the last follow-up. 88% of the patients (23/26) with preoperative coronal imbalance (TS > 20 mm) restored coronal balance at the final follow-up. 87% of the patients (14/16) with preoperative sagittal imbalance (SVA > 40 mm) restored sagittal balance at the final follow-up. The mean operation time and blood loss were 286 min and 941 mL, respectively. No patients had neurological complications or implant failure.

Conclusion

The surgical strategy of apical region correction and global balance with 3 rods is a safe and effective alternative for the surgical treatment of severe and rigid scoliosis.

Early-onset scoliosis: a narrative review

Early-onset scoliosis (EOS) is defined as any spinal deformity that is present before 10 years old, regardless of etiology.

Deformity must be evaluated based on the intercorrelation between the lungs, spine, and thorax.

Curvatures of early-onset have increased risk of progression, cardiorespiratory problems, and increased morbidity and mortality.

Progression of the deformity may produce thoracic insufficiency syndrome, where a distorted thorax is unable to support normal respiratory function or lung growth.

Management and treatment of EOS should pursue a holistic approach in which the psychological impact and quality of life of the patient are also taken into consideration.

Growth-friendly surgical techniques have not met the initial expectations of correcting scoliotic deformity, promoting thoracic growth, and improving pulmonary function.

Posterior-only surgical correction with heavy halo-femoral traction for the treatment of extremely severe and rigid adolescent idiopathic scoliosis (> 130°)

INTRODUCTION

The treatment of extremely severe and rigid spinal deformities was a great surgical challenge. Pulmonary impairment often occurred, which increased the challenges to already daunting surgical approaches. The present study was performed to evaluate the safety and efficacy of posterior-only surgical correction with heavy halo-femoral traction (HFT) for the treatment of extremely severe and rigid adolescent idiopathic scoliosis (AIS) of more than 130°.

MATERIALS AND METHODS

From 2010 to 2017, 11 patients suffered from extremely severe and rigid AIS of more than 130° underwent posterior-only surgical correction with HFT. The preoperative mean coronal Cobb angle of major curve was 139.01° ± 5.83°, and the mean flexibility was 17.21% ± 3.33%; the mean angle of thoracic kyphosis (TK) and lumbar lordosis (LL) were 65.02° ± 7.21° and 39.05° ± 4.08°, respectively; the mean trunk shift (TS) and sagittal vertical axis (SVA) were 3.3 ± 0.97 cm and 3.97 ± 1.16 cm, respectively; moreover, the percent forced vital capacity (FVC%) and percent forced expiratory volume in 1 s (FEV1%) were 50.08% ± 6.07% and 53.46% ± 5.96%, respectively; the mean body height and weight were 140.09 ± 4.95 cm and 37 ± 4.34 kg, respectively.

RESULTS

The mean duration of surgery was 335.91 ± 48.31 min and blood loss was 1590 ± 520.1 ml. The average period of follow-up was 32.18 ± 8.17 months. After heavy HFT, the mean coronal Cobb angle of major curve was reduced to 82.98° ± 6.91° with correction rate of 40.39%. After posterior-only surgical correction, the mean coronal Cobb angle was further reduced to 51.17° ± 5.4° with correction rate of 63.27%. The postoperative mean TK, LL, TS and SVA were improved to 23.85° ± 5.14°, 44.95° ± 2.26°, 1.32 ± 0.72 cm and 1.42 ± 0.83 cm, respectively. At the final follow-up, the corrective loss rate of Cobb angle was only 0.72%; moreover, the mean FVC% and FEV1% were increased to 65.45% ± 5.29% and 69.08% ± 5.32% with improvement of 15.36% and 15.62%, respectively; the mean body height and weight were increased to 154.45 ± 5.32 cm and 45 ± 4.02 kg with improvement of 14.36 cm and 8 kg, respectively. The spinal cord function was stable, and there were no new neurological symptoms after correction.

CONCLUSIONS

Posterior-only surgical correction with heavy HFT could be safe and effective for the treatment of extremely severe and rigid AIS of more than 130° in reducing the incidence of complications and greatly improving curve correction.

Elucidating the Potential Mechanisms Underlying Distraction Spinal Cord Injury-Associated Neuroinflammation and Apoptosis

The incidence of distraction spinal cord injury (DSCI), which results from spinal cord ischemia due to vascular compromise and spinal cord tract disturbances, remains high. Furthermore, because no ideal animal model that mimics DSCI in clinical settings is available thus far, the related molecular mechanisms underlying DSCI remain unclear. Thus, this study aimed to establish a porcine model of DSCI and investigate the neuroinflammation and apoptosis mechanisms in these pigs. Before surgery, all pigs were randomly divided into three groups: sham group, osteotomy surgery only; the incomplete distraction spinal cord injury (IDSCI) and complete distraction spinal cord injury (CDSCI) group, osteotomy plus DSCI surgery with a motor-evoked potential (MEP) amplitude decreased by approximately 75% and 100%, respectively. After surgery, modified Tarlov scoring and MRC muscle strength scoring were used to evaluate neurologic function in each group. We observed the distracted spinal cord using MRI, and then all pigs were sacrificed. Inflammatory cytokine levels in the spinal cord and cerebrospinal fluid (CSF) were also analyzed. We used immunofluorescence staining to assess the neuronal and microglial structure and function and astrocyte hyperplasia in the central DSCI lesions (T15). Western blotting was used to determine the expression of apoptosis-related proteins. Results showed that the modified Tarlov scoring and muscle strength decreased significantly in the two DSCI groups. T2-MRI showed a relative enhancement at the center of the DSCI lesions. H&E and Lxol fast blue staining revealed that spinal cord distraction destroyed the normal structure of spinal cord tissues and nerve fiber tracts, exacerbating inflammatory cell infiltration, hyperemia, and edema. The IL-1β, IL-6, and TNF-α levels increased in the spinal cord and CSF following DSCI. Immunofluorescence staining results indicated the GFAP, Iba-1 expression increased following DSCI, whereas the NeuN expression reduced. Moreover, DSCI promoted the protein expression of P53, Bcl-2-associated X protein (Bax), and Caspase-3 in the spinal cord tissues, whereas it reduced the Bcl-2 expression. This study successfully established a porcine DSCI model that closely mimics DSCI in clinical settings, and clarified the mechanisms underlying DSCI-associated neuroinflammation and apoptosis; thus, our findings highlight potential DSCI-treatment strategies for further establishing suitable drug therapies.

Outcome after Posterior Vertebral Column Resection in Patients with Severe Osteoporotic Fractures—A Retrospective Analysis from Two Centers

Background and Objectives: In osteoporotic fractures of the spine with resulting kyphosis and threatening compression of neural structures, therapeutic decisions are difficult. The posterior vertebral column resection (pVCR) has been described by different authors as a surgical treatment in a single-stage posterior procedure. The aim of this study is to evaluate midterm outcomes of patients treated by pVCR due to severe osteoporotic fractures. Materials and Methods: Retrospective data analysis of all the patients treated for osteoporotic fractures by pVCR from 2012–2020 at two centers was performed. Demographic data, visual analog scale (VAS), Frankel scale (FS), Karnofsky performance status (KPS), radiological result and spinal fusion rates were evaluated. Results: A total of 17 patients were included. The mean age was 70 ± 10.2 y. The mean VAS decreased significantly from 7.7 ± 2.8 preoperatively to 3.0 ± 1.6 at last follow-up (p < 0.001) and the segmental kyphosis decreased from 29.4 ± 14.1° to 7.9 ± 8.0° (p < 0.001). The neurologic function on the FS did not worsen in any and improved in four of the patients. The median KPS remained stable over the whole observation period (70% vs. 70%). Spinal fusion was observed in nine out of nine patients who received CT follow-up >120 days after index surgery. Conclusions: This study showed that pVCR is a safe surgical technique with few surgical complications and no neurological deterioration considering the cohort. The patients’ segmental kyphosis and VAS improved significantly, while the KPS remained stable.

Pre-operative Halo-Pelvic Traction for Neurofibromatosis Patients with Severe Proximal Thoracic Spinal Deformity: Indications and Early Treatment Outcome

Introduction:

To report the indications and early treatment outcomes of pre-operative halo-pelvic traction in patients with neurofibromatosis associated with severe proximal thoracic (PT) spinal deformity.

Materials and methods:

We reviewed four patients with neurofibromatosis with severe PT spinal deformity. Case 1, a 16-year-old male presented with severe PT kyphoscoliosis (scoliosis: 89°, kyphosis: 124°) and thoracic myelopathy. Case 2 was a 14-year-old, skeletally immature male who presented with a PT lordoscoliosis (scoliosis: 85°). Case 3, a 13-year-old male, presented with severe PT kyphoscoliosis (scoliosis: 100°, kyphosis: 95°). Case 4, a 35-year-old gentleman, presented with severe PT kyphoscoliosis (scoliosis: 113°, kyphosis: 103°) and thoracic myelopathy. All patients underwent pre-operative halo-pelvic traction. After a period of traction, all patients underwent posterior spinal fusion (PSF) with autologous bone grafts (local and fibula bone grafts) and recombinant human bone morphogenetic protein-2 (rhBMP-2).

Results:

Both patients with thoracic myelopathy regained near normal neurological status after halo-pelvic traction. Following traction, the scoliosis correction rate (CR) ranged from 18.0% to 38.9%, while the kyphosis CR ranged from 14.6% to 37.1%. Following PSF, the scoliosis CR ranged from 24.0% to 58.8%, while the kyphosis CR ranged from 29.1% to 47.4%. The total distraction ranged from 50-70mm. Duration of distraction ranged from 26-95 days. The most common complication encountered during halo-pelvic traction was pin-related e.g. pin tract infection, pin loosening and migration, osteomyelitis, and halo-pelvic strut breakage. No patients had cranial nerve palsies or neurological worsening.

Conclusion:

Pre-operative correction of severe PT spinal deformities could be performed safely and effectively with the halo-pelvic device prior to definitive surgery.

Surgical Causes of Significant Intraoperative Neuromonitoring Signal Changes in Three-Column Spinal Surgery

Study Design

Retrospective case series.

Purpose

To evaluate the risks and causes of neurologic complications in three-column spinal surgery by analyzing intraoperative neurophysiological monitoring (IONM) data.

Overview of Literature

Three-column spinal surgery, which may be required to correct complex spinal deformities or resection of spinal tumors, is known to carry a high risk of neurologic complications. However, few studies reported a specific surgical procedure related to a significant IONM signal change during surgery.

Methods

Multimodality IONM data, including somatosensory-evoked potentials (SSEP) and motor-evoked potentials (MEP), were reviewed in 64 patients who underwent three-column spinal surgery from 2011 to 2015. Surgical procedures included posterior vertebral column resection, pedicle subtraction osteotomy, total en bloc spondylectomy, piecemeal spondylectomy, and corpectomy with laminectomy (n=27) in three cervical, 34 thoracic, and 31 lumbar procedures.

Results

Significant IONM signal changes occurred in 11 of 64 (17.1%) patients. SSEP and MEP were changed in 11 patients. Postoperative neurologic deterioration occurred in 54.5% (6 of 11) of the patients, and two of them were permanent. There was no postoperative neurologic deterioration in patients without significant signal change. Suspected causes of IONM data changes are as follows: adhesion/tethering, translation, contusion, and perfusion.

Conclusions

Based on the results of this study, to enhance neurologic safety in three-column spinal surgery, surgeons should pay attention to protect the spinal cord from mechanical insult, especially when the spinal column was totally destabilized during surgery, and not to compromise perfusion to the spinal cord in close cooperation with a neurologist and anesthesiologist.

Is there an indication for surgery in patients with spinal deformities? - A critical appraisal

Background

High-quality evidence exists to support physiotherapy and brace treatment for scoliosis and other spinal deformities. However, according to previous systematic reviews, it seems that no evidence exists for surgery. Nevertheless, the number of research articles focussing on spinal surgery highly exceeds the number of articles focussing on conservative treatment.

Objective

The purpose of this study is to conduct an updated search for systematic reviews providing high-quality evidence for spinal surgery in patients with spinal deformities.

Method

A narrative review including PubMed and the Cochrane database was conducted on April 12, 2020, with the following search terms: (1) spinal deformities, surgery, systematic review and outcome; (2) kyphosis, surgery, systematic review and outcome; (3) Scheuermann's disease, surgery, systematic review and outcome, and (4) scoliosis, surgery, systematic review and outcome.

Results

No reviews containing prospective controlled or randomised controlled studies were found providing evidence for surgery.

Conclusions

A general indication for spine surgery just based on the Cobb angle is not given. In view of the long-term unknown variables and the possible long-term complications of such treatment, a surgical indication for patients with spinal deformities must be reviewed on an individual basis and considered carefully. A current systematic review appears necessary in order to be able to draw final conclusions on the indication for surgery in patients with spinal deformities.

Clinical implications

In view of the increasing number of surgeons with an affiliation to industry, the indication for surgery needs to be given by independent conservative specialists for spinal deformities in order to provide an objective recommendation.

Pedicle Subtraction Osteotomy in Lateral Position: A New Strategy for Correcting Severe Thoracolumbar Kyphosis Combined with Hip Flexion Contracture in Ankylosing Spondylitis

Objective

To describe spinal osteotomy in lateral position, which might be a new strategy for correcting thoracolumbar kyphotic deformity combined with severe hip flexion contracture, and to present two cases in which this method was successfully performed.

Methods

Spinal osteotomies in lateral position were performed in two patients with severe thoracolumbar kyphosis combined with hip flexion contracture, which was not suitable for operation in the prone position. Case 1: a 33‐year‐old female AS patient still had severe hip flexion contracture due to poor rehabilitation after total hip replacement (THR). The range of movement of the hip was only about 15° in right and 10° in left. Pre‐operativethoracic kyphosis (TK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL), and sagittal vertical axis (SVA) were 52.4°, 49.1°, 42.7°, and 315 mm, respectively. Pedicle subtraction osteotomy (PSO) at L3 was performed in the lateral position. The eggshell procedure was used during osteotomy. Case 2: a 45‐year‐old male AS patient presented coexisting rigid thoracolumbar kyphosis and hip flexion contracture. The range of movement of the hip was only about 20° in right and 25° in left. Pre‐operativeTK, TLK, LL and SVA were 34.9°, 66.8°, 58.8° and 290.8 mm, respectively. PSO at L₂ was performed in lateral position. The eggshell procedure was also used.

Results

Sagittal malalignments of both patients were greatly improved. For case 1, the total operation time was 5.5 h. The blood loss was 1500 mL and the amount of allogeneic blood transfusion was 1580 mL during the operation. SVA was reduced to 127 mm and LL decreased from preoperative 42.7° to −28.4°. The correction angle through L₃ was 34.7° and the correction angle through the osteotomy segment was 62.9°. For case 2, the duration of surgery was 6.5 h. The operative blood loss was 2000 mL and the total amount of blood transfusion was 2020 mL. SVA was reduced to 209.8 mm and LL decreased from preoperative 58.8° to 9.2°.The correction angle through L₂ was 37.1° and the correction angle through the osteotomy segment was 55°. No intra‐operative or post‐operative complications were observed. Six months after PSO, case 1 had good posture for standing and sitting. The case 2 underwent bilateral THRs nine months after PSO.

Conclusion

PSO could be performed in the lateral position successfully. For AS patients who cannot be placed in the prone position due to coexisting severe thoracolumbar kyphosis and hip flexion contracture, performing spinal osteotomy in the lateral position as the first step is an alternative.

Center of rotation analysis for thoracic and lumbar 3-column osteotomies in patients with sagittal plane spinal deformity: insights in geometrical changes can improve understanding of correction mechanics

OBJECTIVE

Three-column osteotomy (3CO) is used for severe spinal deformities. Associated complications include sagittal translation (ST), which can lead to neurological symptoms. Mismatch between the surgical center of rotation (COR) and the concept of the ideal COR is a potential cause of ST. Matching surgical with conceptual COR is difficult with pedicle subtraction osteotomy (PSO) and vertebral column resection (VCR). This mismatch influences correction geometry, which can prevent maximum possible correction. The authors' objective was to examine the sagittal correction geometry and surgical COR of thoracic and lumbar 3CO.

METHODS

In a retrospective study of patients with PSO or VCR for severe sagittal plane deformity, analysis of surgical COR was performed using pre- and postoperative CT scans in the PSO group and digital radiographs in the VCR group. Radiographic analysis included standard deformity measurements and regional kyphosis angle (RKA). All patients had 2-year follow-up, including neurological outcome. Preoperative CT scans were studied for rigid osteotomy sites versus mobile osteotomy sites. Additional radiographic analysis of surgical COR was based on established techniques superimposing pre- and postoperative images. Position of the COR was defined in a rectangular net layered onto the osteotomy vertebrae (OVs).

RESULTS

The study included 34 patients undergoing PSO and 35 undergoing VCR, with mean ages of 57 and 29 years and mean RKA corrections of 31° and 49°, respectively. In the PSO group, COR was mainly in the anterior column, and surgical and conceptual COR matched in 22 patients (65%). Smaller RKA correction (27° vs 32°, p = 0.09) was seen in patients with anterior eccentric COR. Patients with rigid osteotomy sites were more likely to have an anterior eccentric COR (41% vs 11%, p = 0.05). In the VCR group, 20 patients (57%) had single-level VCR and 15 (43%) had multilevel VCR. COR was mainly located in the anterior or middle column. Mismatch between surgical and conceptual COR occurred in 24 (69%) patients. Larger RKA correction (63° vs 45°, p = 0.03) was seen in patients with anterior column COR. Patients with any posterior COR had a smaller RKA correction compared to the rest of the patients (42° vs 61°, p = 0.007).

CONCLUSIONS

Matching the surgical with the conceptual COR is difficult and in this study failed in one- to two-thirds of all patients. In order to avoid ST during correction of severe deformities, temporary rods, tracking rods, or special instruments should be used for correction maneuvers.

The impact of postoperative neurologic complications on recovery kinetics in cervical deformity surgery

Objective:

The objective of the study is to investigate which neurologic complications affect clinical outcomes the most following cervical deformity (CD) surgery.

Methods:

CD patients (C2-C7 Cobb >10°, CL >10°, cSVA >4 cm or chin-brow vertical angle >25°) >18 years with follow-up surgical and health-related quality of life (HRQL) data were included. Descriptive analyses assessed demographics. Neurologic complications assessed were C5 motor deficit, central neurodeficit, nerve root motor deficits, nerve sensory deficits, radiculopathy, and spinal cord deficits. Neurologic complications were classified as major or minor, then: intraoperative, before discharge, before 30 days, before 90 days, and after 90 days. HRQL outcomes were assessed at 3 months, 6 months, and 1 year. Integrated health state (IHS) for the neck disability index (NDI), EQ5D, and modified Japanese Orthopaedic Association (mJOA) were assessed using all follow-up time points. A subanalysis assessed IHS outcomes for patients with 2Y follow-up.

Results:

153 operative CD patients were included. Baseline characteristics: 61 years old, 63% female, body mass index 29.7, operative time 531.6 ± 275.5, estimated blood loss 924.2 ± 729.5, 49% posterior approach, 18% anterior approach, 33% combined. 18% of patients experienced a total of 28 neurologic complications in the postoperative period (15 major). There were 7 radiculopathy, 6 motor deficits, 6 sensory deficits, 5 C5 motor deficits, 2 central neurodeficits, and 2 spinal cord deficits. 11.2% of patients experienced neurologic complications before 30 days (7 major) and 15% before 90 days (12 major). 12% of neurocomplication patients went on to have revision surgery within 6 months and 18% within 2 years. Neurologic complication patients had worse mJOA IHS scores at 1Y but no significant differences between NDI and EQ5D (0.003 vs. 0.873, 0.458). When assessing individual complications, central neurologic deficits and spinal cord deficit patients had the worst outcomes at 1Y (2.6 and 1.8 times worse NDI scores, P = 0.04, no improvement in EQ5D, 8% decrease in EQ5D). Patients with sensory deficits had the best NDI and EQ5D outcomes at 1Y (31% decrease in NDI, 8% increase in EQ5D). In a subanalysis, neurologic patients trended toward worse NDI and mJOA IHS outcomes (P = 0.263, 0.163).

Conclusions:

18% of patients undergoing CD surgery experienced a neurologic complication, with 15% within 3 months. Patients who experienced any neurologic complication had worse mJOA recovery kinetics by 1 year and trended toward worse recovery at 2 years. Of the neurologic complications, central neurologic deficits and spinal cord deficits were the most detrimental.

The use of three rods in correcting severe scoliosis

PURPOSE

The three-rod technique, utilising a short apical concavity rod is an option to achieve controlled correction in severe scoliosis. We describe this technique, the complications encountered, and the long-term outcomes.

METHOD

All paediatric patients who had at least 2 years follow-up after undergoing corrective surgery for scoliosis ≥ 100° using 3 parallel rods were included. Radiographs were assessed to evaluate the correction and clinical records examined for any loss of correction, complications, revision procedures or neuromonitoring events.

RESULTS

Twenty-five patients met the inclusion criteria. Four underwent prior anterior fusion to prevent crankshaft phenomenon. The mean angle of the deformity was 112.0° (range 100.3-137.1). Mean maximal kyphosis was 48.8° (range 11.4-78.8°) and mean curve flexibility 4.4% (range 0-37.0%). Intraoperative traction achieved an average of 70.4% (95% CI 56.6-84.1%). Nine patients (39%) showed a reduction in MEPs during definitive surgery. All returned to within 75% of baseline by the end of surgery. All patients had normal postoperative neurology. One patient underwent removal of hardware for late infection. The mean overall Cobb correction was 55.7° (95% CI 50.2-61.2°), equating to 50.2% (95% CI 44.9-55.4%) of the mean initial deformity. Thoracic kyphosis reduced by a mean of 18.2° (95% CI 12.8-23.6°).

CONCLUSION

Our series suggests that three-rod constructs are able to safely and effectively achieve 50% correction of severe scoliosis.

How helpful is the halo-gravity traction in severe spinal deformity patients?: A systematic review and meta-analysis

PURPOSE

This study sought to evaluate the complications and clinic outcome in radiographic parameters, pulmonary function, and nutritional status of halo-gravity traction (HGT) in treating severe spinal deformity.

METHODS

Embase, PubMed, Cochrane, Web of Science databases were searched comprehensively for relevant studies from inception to February 2021, by using combined text and MeSH terms and English language restriction was used. The data, including radiographic parameters, pulmonary function (FVC %), and nutritional status (BMI) was extracted from included studies. All meta-analyses were conducted using random or fixed-effects models according the between-study heterogeneity, estimated with I².

RESULTS

Four hundred and forty-six studies were identified and twelve studies with a total of 372 patients were included in this review. Compared with pre-traction values, there were reduction in cobb angle of 28.12° [95% CI (22.18, 34.18)], decrease in thoracic kyphosis of 26.76°[95% CI (20.73, 32.78)], improvements in spine height[SMD = -0.89, 95% CI (- 1.56, - 0.21)] and in coronal balance[WMD = - 0.03, 95% CI (- 1.56, - 0.21), P = 0.84] with preoperative halo-gravity traction for severe spinal deformity patients. Besides, our pooled analysis showed the improvement in pulmonary function (FVC %) [WMD = - 9.56, 95% CI (- 1.56, - 0.21)] and increase in nutritional status (BMI) [WMD = - 0.50, 95% CI (- 1.56, - 0.21)].

CONCLUSION

Partial correction can be achieved by preoperative HGT, thereby reducing the difficulty of the operation and the risk of neurologic injury caused by excessive correction. Moreover, preoperative HGT can improve pulmonary function and nutritional status and, thus, increase patients' tolerance to surgery.

Outcomes of Early Hemivertebrectomy in Children with Congenital Scoliosis: A Prospective Follow-up Study

BACKGROUND AND AIMS

Posterolateral hemivertebrectomy with monosegmental instrumentation at an early age is an established method to correct congenital scoliosis but is associated with a relatively high risk of instrumentation failure and health-related quality of life outcomes are not available. We aimed to investigate the effects hemivertebrectomy with postoperative hip spica cast on complications and health-related quality of life in small children with congenital scoliosis.

MATERIALS AND METHODS

A follow-up study of 30 children (at mean age = 3.4 years, range = 1.0-8.5 years) undergoing posterolateral hemivertebrectomy and short pedicle instrumentation. Children were immobilized postoperative with hip spica cast for 6 weeks and immobilization for 4 months using a rigid thoracolumbosacral orthosis. The Caregivers filled out Scoliosis Research Society 24 outcome questionnaire preoperatively, at 6 months, and at final follow-up visit on behalf of their child. Standing radiographs were obtained preoperatively, postoperatively in the cast, and standing at final follow-up.

RESULTS

Mean major curve was 41° (range = 26°-87°) preoperatively and was corrected to 14° (4.0°-35°) at final follow-up. Eight (27%) children had postoperative complications, including three (10%) deep surgical site infections. The Scoliosis Research Society 24 back domain showed an improvement from a mean of 3.8 preoperatively to 4.4 at final follow-up (p < 0.001). Function from back condition domain showed a significant deterioration from 4.2 preoperatively to 3.7 at 6 months (p = 0.020) but improved back to baseline at final follow-up (4.2, p = 0.0022 6 months vs final follow-up).

CONCLUSION

Hemivertebrectomy with short instrumentation resulted into 64% correction of scoliosis and improved health-related quality of life in back pain and function domains.

Comparison of Posterior Unilateral Vertebral Column Resection Versus Posterior Vertebral Column Resection for Severe Thoracolumbar Angular Kyphosis as a Revision Surgical Modality: A Retrospective Cohort Study

OBJECTIVE

The objective of this study was to determine the safety and efficacy of posterior unilateral vertebral column resection (PUVCR) as revision surgery for severe thoracolumbar angular kyphosis.

PATIENTS AND METHODS

This is a retrospective cohort study. Adult patients undergoing revision surgery for severe thoracolumbar angular kyphosis in 2010-2016 with ≥2-year follow-up at our institution were assessed. Perioperative complications and clinical outcomes, including blood loss, operation time, Visual Analog Scale score, Oswestry Disability Index, and preoperative and postoperative kyphotic angles, were analyzed.

RESULTS

This study included 58 patients who were divided into the PUVCR group and the posterior vertebral column resection (PVCR) group. Age ( P =0.810), sex distribution ( P =0.500), and vertebrae that underwent surgery ( P =0.638) were similar in the 2 groups. Shorter mean operation time was observed in the PUVCR group as compared with the PVCR group ( P <0.001). In addition, less blood loss was recorded in the PUVCR group as compared with the PVCR group ( P =0.001). There were no significant differences between the 2 groups in a change of Visual Analog Scale scores postoperation versus preoperation ( P =0.961), and at postoperative 3 months ( P =0.906), 12 months ( P =0.752), and 24 months ( P =0.811) versus postoperation, respectively. There were no significant differences between the 2 groups in Oswestry Disability Index changes postoperation versus preoperation ( P =0.157), and at postoperative 3 months ( P =0.899), 12 months ( P =0.947), and 24 months ( P =0.811) versus postoperation, respectively. PUVCR and PVCR were comparable in deformity correction ( P =0.434) and final angle correction ( P =0.790). Complication rates in the PUVCR and PVCR groups were 7.1% and 36.7%, respectively.

CONCLUSION

PUVCR has comparable safety and efficacy to PVCR in treating severe thoracolumbar angular kyphosis, with the advantages of the shorter operation time, less blood loss, and fewer complications.

Deformed Complex Vertebral Osteotomy Technique for Management of Severe Congenital Spinal Angular Kyphotic Deformity

OBJECTIVES

To (i) introduce the deformed complex vertebral osteotomy (DCVO) technique for the treatment of severe congenital angular spinal kyphosis; (ii) evaluate the sagittal correction efficacy of the DCVO technique; and (iii) discuss the advantages and limitations of the DCVO technique.

METHODS

Multiple malformed vertebrae were considered a malformed complex, and large-range and angle wedge osteotomy was performed within the complex using the DCVO technique. Patients with local kyphosis greater than 80° who were treated with DCVO and did not have tumors, infections, or a history of surgery were included. A retrospective case study was performed in these patients with severe angular kyphosis who underwent the DCVO technique from 2008 to 2016. Demographic data, the operating time, and the volume of intraoperative blood loss were collected. Spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], and sacral slope [SS]), local and global sagittal parameters (deformity angle, thoracic kyphosis [TK], and lumbar lordosis [LL]), visual analog scale (VAS) score, and Oswestry disability index (ODI) score were recorded pre- and postoperatively. Paired t-tests (α = 0.05) were used for all data (to compare the mean preoperative value with the mean postoperative and most recent follow-up values). P < 0.05 was considered statistically significant.

RESULTS

Twenty-nine patients with a mean age of 34 years (range, 15-55) were included in the final analysis. Seventeen patients were male, and 12 were female. The mean follow-up was 44 months (range, 26-62). The mean operating time was 299 min (range, 260-320 min). The mean blood loss was 2110 mL (range, 1500-2900 mL). Three patients had T7 -T8 deformities (3/29, 10.3%), six had T8 -T9 deformities (6/29, 20.7%), six had T9 -T10 deformities (6/29, 20.7%), 10 had T10 -T11 deformities (10/29, 34.5%), three had T11 -T12 deformities (3/29, 10.3%), and one had T9 -T11 deformities (1/29, 3.4%). The mean local deformity angle significantly improved from 94.9° ± 10.8° to 24.0° ± 2.3° through the DCVO technique, with no significant loss at the follow-up. Moreover, the global sagittal parameters and spinopelvic parameters exhibited ideal magnitudes of improvement; TK decreased from 86.1° ± 12.1° to 28.7° ± 2.5°, LL improved from 94.5° ± 4.1° to 46.1° ± 3.0°, and PI minus LL improved from -60.9° ± 6.5° to -13.7° ± 2.6°. Both the VAS and ODI scores significantly improved at the last follow-up. CSF fistula and neural injury did not occur during the perioperative period. At the last follow-up, fixation failure was not observed.

CONCLUSION

The DCVO technique provides an alternative and effective method for the treatment of congenital severe angular spinal kyphotic deformities and may decrease the occurrence of perioperative complications.

Avoiding Radical Removal of Posterior Elements in Posterior Vertebral Column Resections: A Modified Schwab Grade 6 Osteotomy for Severe Post-Tuberculous Kyphotic Deformity

OBJECTIVE

Posterior vertebral column resection (PVCR) is a versatile technique for correction of severe and rigid spinal deformities, but the high rate of neurological complications is a major disadvantage of this procedure. This study aimed to describe a modified PVCR technique for safe treatment of severe post-tuberculous kyphotic deformity.

METHODS

Four consecutive patients with severe post-tuberculous kyphosis underwent modified PVCRs. Radical removal of the posterior elements was avoided by performing laminectomy in stages, and the posterior vertebral wall and the bases of the spinous processes were maintained throughout the procedure. Perioperative clinical presentation, imaging data, and operative variables were recorded.

RESULTS

Desirable efficacy and clinical outcomes were obtained, including satisfactory correction rates and low estimated blood loss. Neurological status improved in all patients with preoperative neurological deficits, and no postoperative neurological complications were reported.

CONCLUSIONS

Modified PVCRs could prevent excessive handling or overstretching of the spinal cord, reduce bleeding, and provide more security in the correction of severe spinal deformities. Our initial experience showed that this modified procedure might be an alternative to conventional Schwab grade 6 osteotomy for the correction of severe post-tuberculous kyphotic deformity.

New neurologic deficit and recovery rates in the treatment of complex pediatric spine deformities exceeding 100 degrees or treated by vertebral column resection (VCR)

STUDY DESIGN

Prospective multicenter international observational study.

OBJECTIVE

To investigate incidence of new neurologic deficit (NND) and the long-term recovery patterns following complex pediatric spine deformity surgery. The SRS M&M reports identify pediatric patients as having higher rate of new neurologic deficit compared with adults, while congenital and neuromuscular deformities are associated with higher new neurologic risks. Very few studies have had the large numbers of pediatric patients with curves exceeding 100 deg to ascertain the new neurologic deficit (NND) rates and recovery patterns as it relates to curve laterality and diagnosis.

METHOD

The FOX pediatric database from 17 international sites was queried for New Neurologic Deficit (NND) as characterized by change in American Spinal Injury Association (ASIA) Lower or Upper Extremity Motor Score. Recovery rates at specific intervals were recorded and related to the curve type and etiology.

RESULTS

Data of 286 consecutive patients with normal pre-operative neurologic exams were reviewed. There were 160 females vs 125 males with an average age of 14.6 years. NND occurred in 27 patients (9.4%) in the immediate post-operative period. Diagnostic categories included idiopathic scoliosis (3 patients); idiopathic kyphoscoliosis(5 patients); congenital scoliosis (7 patients); congenital kyphoscoliosis (4 patients); congenital kyphosis (6 patients), other kyphosis (1 patient) and syndromic (1 patient). 1 patient was lost to follow-up (f/u) after discharge; 1 had chronic deficits at the first post-operative erect visit (from discharge to 9 months f/u) and was subsequently lost to follow-up; 2 patients were improving at 1-year f/u but lost to subsequent f/u. 16 patients had normal neurologic function by the time of the first post-operative erect visit, 21 patients at 1-year f/u and 21 patients at the 2-year f/u. 2 patients (0.69%) had improved NND at 2-year mark.

CONCLUSION

A significant proportion of patients with complex spine deformity experience NND. However, significant improvement in neurologic function can be expected over time as seen in this study without additional surgical intervention in most cases. Congenital deformities accounted for 63% of the patients experiencing NND.

Characterization of complex vertebral transposition (gamma deformity) > 180 degrees: clinical and radiographic outcomes of halo gravity traction and vertebral column resection (VCR)

STUDY DESIGN

Prospective case series OBJECTIVE: Results of surgical treatment of complex vertebral transposition "Gamma Deformity" > 180 degrees with halo gravity traction (HGT) and vertebral column resection (VCR). We recently published a novel classification system for complex spine deformities of which complex vertebral transposition > 180 degrees (Gamma; type 3) was described. Halo gravity traction (HGT) has been shown to mitigate surgical risk in complex spine deformity correction and in some cases obviates the need for three-column osteotomy. However, we are not aware of report of its utilization in treating Gamma deformities with or without vertebral column resection (VCR).

METHODS

A consecutive series of 13 patients with Gamma deformity (GD) were prospectively enrolled at a single site in West Africa. Standard radiographs and 3D computerized tomography (CT) were done to assess coronal and sagittal vertebral transposition (CVT and SVT). The HGT with 50% of body weight was applied over several weeks followed by VCR. Demographics, operative data, radiographic parameters, and complications data were collected.

RESULTS

13 pts with GD underwent HGT for an avg of 110 days prior to definitive surgery. Etiologies were Congenital-11 pts and Neurofibromatosis-2 pts. Average age: 17.8 years; Pts were reviewed at 3 months post-op and at minimum 2-year follow-up. Preop myelopathy was present in five patients. Pre-op CVT avg 75% and was corrected in all cases post-op. SVT avg 211 deg and improved with HGT by 36% and corrected to 53 deg (74% correction) post-op. Thoracic kyphosis avg -42 deg and averaged 48 deg post-op. Intra-op spinal cord monitoring (SCM) alerts occurred in 8 pts (61%). Post-operative LEM deficits occurred in 5 pts: 2 fully recovered by 3 months and 2 year follow-up, while the remaining 3 improved but had residual motor deficits at final follow-up. There was one post-operative mortality.

CONCLUSION

The management of complex vertebral transposition (Gamma deformity) > 180 degrees with HGT prior to VCR is not only effective in some patients, but also associated with high SCM alerts and neurologic injury rates. Myelopathic patients with thoracic deformities are at higher risk of developing permanent neurologic deficits. Surgeons should be aware of this rare and unusual deformity and consider HGT and VCR bearing in mind the technical challenges and high complication rate.

Using Satellite Rod Technique in Patients with Severe Kyphoscoliosis Undergoing Three-Column Osteotomy: A Minimum of 2 Years' Follow-up

OBJECTIVE

To introduce the satellite rod technique utilized in severe spinal deformity after three-column osteotomy (3CO) and to evaluate the radiographic and clinical outcomes at 2-year follow-up, further discussing its utilization in this particular cohort.

METHODS

A total of 32 (19 females and 13 males) with an average age of 32.9 ± 18.3 years from December 2012 to March 2016 were retrospectively reviewed. Radiographic measurements were performed on standing full-spine anteroposterior and lateral radiographs preoperatively, postoperatively, and at last follow-up. The coronal parameters including Cobb angle and distance between C₇ plumb line and center sacral vertical line (C7PL-CSVL), as well as the sagittal parameters including global kyphosis (GK) and sagittal vertical axis (SVA) were measured at three time points. The Scoliosis Research Society-22 questionnaire (SRS-22) was fulfilled preoperatively and at each follow-up. Paired t test would be used to determine whether there was a significant difference between time points.

RESULTS

A total of 32 patients were enrolled in this study with mean age of 32.9 ± 18.3 (range, 12 to 66) years old. Twenty patients underwent pedicle subluxation osteotomy (PSO) and 12 patients underwent vertebral column resection (VCR). The pathogenesis of this cohort included neuromuscular scoliosis (11 cases), congenital kyphoscoliosis (seven with hemivertebrae and five with segmentation failure), degenerative spinal deformity (five cases), and thoracolumbar tuberculosis with angular kyphosis (four cases). The post-operative Cobb angle decreased significantly from 49.1° ± 28.0° to 19.0° ± 16.7° with a correction rate of 65.2% ± 21.8%. At final follow-up, the average Cobb angle was 19.4° ± 16.9° and no obvious loss of correction was found. The preoperative, postoperative, and last follow-up C7PL-CSVL were 23.9 ± 14.5 mm, 15.7 ± 11.1 mm, and 12.1 ± 7.4 mm, respectively. Significant postoperative improvement was attained while there was no change observed at last follow-up. Postoperative GK significantly improved from 73.8° ± 28.1° to 23.2° ± 11.7° with the correction rate of 66.0% ± 17.9%. SVA decreased significantly from 42.9 ± 33.9 mm to 24.1 ± 21.1 mm. The average GK and SVA at final follow-up were 22.7° ± 10.1° and 23.5 ± 21.1 mm, respectively and no obvious loss of correction was observed of them during follow-up. In addition, no change or loss of motor or somatosensory evoked potential occurred during surgery. During the follow-up, two malposition screws and one rod breakage were found.

CONCLUSION

The satellite rod used in patients with severe kyphoscoliosis undergoing 3CO could yield favorable radiological and clinical outcomes. With the utilization of this technique, the coronal and sagittal balance could be well-maintained during follow-up.

Adult Spinal Deformity: Current Concepts and Decision-Making Strategies for Management

Adult spinal deformity (ASD) is characterized by three-dimensional abnormalities of the thoracic or thoracolumbar spine that exerts significant impacts on the health-related quality of life (HRQoL). With the important effects that deformity of the sagittal plane exerts on the HRQoL, there have been paradigm shifts in ASD evaluation and management. Loss of lumbar lordosis is recognized as a key driver of ASD followed by reducing kyphosis, pelvic retroversion, and knee flexion. The Scoliosis Research Society (SRS)– Schwab classification reflects the sagittal spinopelvic parameters that correlate pain and disability in ASD patients. Although the SRS–Schwab classification provides a realignment target framework for surgeons, a structured patient-specific systemic approach is crucial for the process of decision-making. ASD management should be focused on restoring age-specific harmonious alignment and should consider the comorbidities and risk factors of each patient to prevent catastrophic complications and enhance the HRQoL.

Comparison of MRI, [18F]FDG PET/CT, and 99mTc-UBI 29-41 scintigraphy for postoperative spondylodiscitis-a prospective multicenter study

Purpose

Postoperative infection still constitutes an important complication of spine surgery, and the optimal imaging modality for diagnosing postoperative spine infection has not yet been established. The aim of this prospective multicenter study was to assess the diagnostic performance of three imaging modalities in patients with suspected postoperative spine infection: MRI, [¹⁸F]FDG PET/CT, and SPECT/CT with ^99mTc-UBI 29-41.

Methods

Patients had to undergo at least 2 out of the 3 imaging modalities investigated. Sixty-three patients enrolled fulfilled such criteria and were included in the final analysis: 15 patients underwent all 3 imaging modalities, while 48 patients underwent at least 2 imaging modalities (MRI + PET/CT, MRI + SPECT/CT, or PET/CT + SPECT/CT). Final diagnosis of postoperative spinal infection was based either on biopsy or on follow-up for at least 6 months. The MRI, PET/CT, and SPECT/CT scans were read blindly by experts at designated core laboratories. Spine surgery included metallic implants in 46/63 patients (73%); postoperative spine infection was diagnosed in 30/63 patients (48%).

Results

Significant discriminants between infection and no infection included fever (P = 0.041), discharge at the wound site (P < 0.0001), and elevated CRP (P = 0.042). There was no difference in the frequency of infection between patients who underwent surgery involving spinal implants versus those who did not. The diagnostic performances of MRI and [¹⁸F]FDG PET/CT analyzed as independent groups were equivalent, with values of the area under the ROC curve equal to 0.78 (95% CI: 0.64–0.92) and 0.80 (95% CI: 0.64–0.98), respectively. SPECT/CT with ^99mTc-UBI 29-41 yielded either unacceptably low sensitivity (44%) or unacceptably low specificity (41%) when adopting more or less stringent interpretation criteria. The best diagnostic performance was observed when combining the results of MRI with those of [¹⁸F]FDG PET/CT, with an area under the ROC curve equal to 0.938 (95% CI: 0.80–1.00).

Conclusion

[¹⁸F]FDG PET/CT and MRI both possess equally satisfactory diagnostic performance in patients with suspected postoperative spine infection, the best diagnostic performance being obtained by combining MRI with [¹⁸F]FDG PET/CT. The diagnostic performance of SPECT/CT with ^99mTc-UBI 29-41 was suboptimal in the postoperative clinical setting explored with the present study.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-020-05109-x.