Minimally invasive reduction and percutaneous posterior fixation of one-level traumatic thoraco-lumbar and lumbar spine fractures

Our C-Arm-Free Minimally Invasive Technique for Spinal Surgery: The Thoracolumbar and Lumbar Spine-Based on Our Experiences

Background and Objectives: The implementation of intraoperative imaging in the procedures performed under the guidance of the same finds its history dating back to the early 1990s. This practice was abandoned due to many deficits and practicality. Later, fluoroscopy-dependent techniques were developed and have been used even in the present time, albeit with several disadvantages. With the recent advancement of several complex surgical techniques, which demand higher accuracy and are in conjunction with the existence of radiation exposure hazard, C-arm-free techniques were introduced. In this review study, we aim to demonstrate the various types of these techniques performed in our hospital. Materials and Methods: We have retrospectively analyzed and collected imaging data of C-arm-free, minimally invasive techniques performed in our hospital. The basic steps of the procedures are described, following with a discussion, along with the literature of findings, enlisting the merits and demerits. Results: MIS techniques of the thoracolumbar and lumbar spine that do not require the use of the C-arm can offer excellent results with high precision. However, several disadvantages may prevail in certain circumstances such as the navigation accuracy problem where in the possibility of perioperative complications comes a high morbidity rate. Conclusions: The accustomedness of performing these techniques requires a steep learning curve. The increase in accuracy and the decrease in radiation exposure in complex spinal surgery can overcome the burden hazards and can prove to be cost-effective.

Improvement of vertebral body fracture reduction utilizing a posterior reduction tool: a single-center experience

BACKGROUND

Extensive research regarding instabilities and prevention of kyphotic malalignment in the thoracolumbar spine exists. Keystones of this treatment are posterior instrumentation and anterior vertebral height restoration. Anterior column reduction via a single-stage procedure seems to be advantageous regarding complication, blood loss, and OR-time. Mechanical elevation of the anterior cortex of the vertebra may prevent the necessity of additional anterior stabilization or vertebral body replacement. The purpose of this study was to examine (1) if increased bony reduction in the anterior vertebral cortex could be achieved by utilization of an additional reduction tool, (2) if postoperative loss of vertebral height could be reduced, and (3) if anterior column reduction is related to clinical outcome.

METHODS

From one level I trauma center, 173 patients underwent posterior stabilization for fractures of the thoracolumbar region between 2015 and 2020. Reduction in the vertebral body was performed via intraoperative lordotic positioning or by utilization of an additional reduction tool (Nforce, Medtronic). The reduction tool was mounted onto the pedicle screws and removed after tightening of the locking screws. To assess bony reduction, the sagittal index (SI) and vertebral kyphosis angle (VKA) were measured on X-rays and CT images at different time points ((1) preoperative, (2) postoperative, (3) ≥ 3 months postoperative). Clinical outcome was assessed utilizing the Ostwestry Disability Index (ODI).

RESULTS

Bisegmental stabilization of AO/OTA type A3/A4 vertebral fractures was performed in 77 patients. Thereof, reduction was performed in 44 patients (females 34%) via intraoperative positioning alone (control group), whereas 33 patients (females 33%) underwent additional reduction utilizing a mechanical reduction tool (instrumentation group). Mean age was 41 ± 13 years in the instrumentation group (IG) and 52 ± 12 years in the control group (CG) (p < 0.001). No differences in terms of gender and comorbidities were found between the two groups. Preoperatively, the sagittal index (SI) was 0.69 in IG compared to 0.74 in CG (p = 0.039), resulting in a vertebral kyphosis angle (VKA) of 15.0° vs. 11.7° (p = 0.004). Intraoperatively, a significantly greater correction of the kyphotic deformity was achieved in the IG (p < 0.001), resulting in a compensation of the initially more severe kyphotic malalignment. The SI was corrected by 0.20-0.88 postoperatively, resulting in an improvement of the VKA by 8.7°-6.3°. In the CG, the SI could be corrected by 0.12-0.86 and the VKA by 5.1°-6.6°. The amount of correction was influenced by the initial deformity (p < 0.001). Postoperatively, both groups showed a loss of correction, resulting in a gain of 0.08 for the SI and 4.1° in IG and 0.03 and 2.0°, respectively. The best results were observed in younger patients with initially severe kyphotic deformity. Considering various influencing factors, clinical outcome determined by the ODI showed no significant differences between both groups.

CONCLUSION

Utilization of the investigated reduction tool during posterior stabilization of vertebral body fractures in a suitable collective of young patients with good bone quality and severe fracture deformity may lead to better reduction in the ventral column of the fractured vertebral body and angle correction. Therefore, additional anterior stabilization or vertebral body replacement may be prevented.

TREATMENT OF THORACOLUMBAR FRACTURES BY CLOSED REDUCTION VIA A PERCUTANEOUS SOLID PEDICLE SCREW

Objectives

Investigate the effect of closed reduction and per- cutaneous pedicle screw fixation in treating thoracolumbar fractures.

Methods

This retrospective study analyzed 12 cases of single-segment thoracolumbar spine fractures without spinal cord and nerve injury at our department from March 2016 to September 2017. Patients were treated with closed reduction, percutaneous reduction, and internal fixation with solid pedicle screws. The operation time, intraoperative blood loss, anterior vertebral body height ratio (AVHR), Cobb angle (CA) of sagittal kyphosis, and VAS of back pain were determined and statistically compared.

Results

The average operation time was 147.2 ± 45.6 min, and the average intraoperative bleeding was 67.8 ± 34.2 mL. All fractured vertebrae were completely reduced, their height was restored, and kyphosis was corrected. The average follow-up period was 10.6 ± 2.7 months, with significant improvements seen in the AVHR, CA of sagittal kyphosis, and VAS score (P < 0.01). One case had a broken rod after three months, and another had a postoperative infection. All the patients achieved bony healing.

Conclusion

The treatment of thoracolumbar fractures by closed reduction and internal fixation with a percutaneous solid pedicle screw is simple, effective, and economical. Level of Evidence VI; Therapeutic Study, Case Series .

Pedicle screw accuracy in thoracolumbar fractures- is routine postoperative CT scan necessary?

BACKGROUND

While several studies report on accuracy rates of pedicle screws, risk factors associated with inaccurate pedicle screw positioning in patients with thoracolumbar fractures are reported rarely. CT scan as a routine postoperative control is advocated by various authors, however its necessity remains unclear.

METHODS

Two hundred forty-five patients were included in this retrospective study. Percutaneous dorsal instrumentation was most commonly performed (n = 201). Classification of Zdichavsky et al. and Rao et al. were used to classify screw misplacement and anterior perforation was further evaluated according to the extent of perforation (< 2 mm; > 2 mm). Multivariate analysis was performed to identify risk factors for misplacement of screws.

RESULTS

One thousand sixty-eight pedicle screws were inserted in 245 patients. Misplacement was found in 51 screws (4.8%) in 42 patients (17.1%) according to the classification of Zdichavsky et al. and in 75 screws (7.0%) in 64 patients (26.1%) according to the classification of Rao et al.. An anterior perforation of the vertebral cortex was found in 56 screws (5.2%). Multivariate analysis showed fracture location in the upper thoracic (p = 0.048) and lumbar spine (p = 0.013) to be the only independent predictors for screw misplacement. In addition a significant correlation between pedicle diameter and the occurrence of screw malposition was found (p = 0.003). No consequences were drawn from postoperative routine CT in asymptomatic patients.

CONCLUSION

An overall low rate of screw misplacement was found with fracture location in the upper thoracic and lumbar spine being the only factors independently associated with the risk of screw misplacement. No consequences were drawn from postoperative routine CT in asymptomatic patients. Therefore its use has to be discussed critically.

Percutaneous versus open pedicle screw fixation for treatment of type A thoracolumbar fractures

BACKGROUND

The purpose of this study was to evaluate the effectiveness between percutaneous and open pedicle screw fixation without fusion for treating type A3 and A4 thoracolumbar fractures. Traumatic thoracolumbar burst fracture is a common pathology without a consensus on the best treatment approach. Percutaneous pedicle screw fixation (PPSF) systems have been recently introduced in the treatment of spinal fractures to reduce the adverse effects associated with the conventional open approaches, such as iatrogenic muscle denervation and pain.

METHODS

A prospective analysis was made to evaluate consecutive 46 patients with type A3 and A4 thoracolumbar fractures. Patients were divided into a percutaneous pedicle screw fixation group (PPSF) and an open pedicle screw fixation group (OPSF). The mean age of patients in PPSF group (12 men, 11 woman) was 49.9 years and in OPSF group (10 men, 13 women) 52.2 years. For the purpose of evaluation, the radiological assessment of the bisegmental Cobb angle, the loss of correction, the volume of blood loss, operation time, cumulative radiation time and dose were recorded and compared.

RESULTS

All patients were followed up for 12 months. There were no significant differences between OPSF and PPSF in the Cobb angle preoperative and postoperative angle and the loss of bisegmental correction. In PPSF group, the mean preoperative Cobb angle was 10.9° and improved by 4.5° postoperatively, and in OPSF group the preoperative angle was 12.1° and postoperatively improved by 3.8°. Significant differences between OPSF and PPSF were found in the mean cumulative radiation time, radiation dose and operation time. PPSF group also had a significantly lower perioperative blood loss.

CONCLUSIONS

Both open and percutaneous short-segment pedicle fixation were safe and effective methods to treat thoracolumbar burst fractures. Percutaneous fixation without fusion seems to be suitable for type A3 and A4 fractures.