Unilateral versus bilateral pedicle screw fixation for degenerative lumbar diseases: a meta-analysis of 10 randomized controlled trials

Is unilateral pedicle screw fixation as effective as bilateral pedicle screw fixation in transforaminal lumbar interbody fusion: a meta-analysis of randomized controlled trials

PURPOSE

This meta-analysis aimed to investigate whether unilateral pedicle screw fixation (UPSF) is comparable to bilateral pedicle screw fixation (BPSF) in transforaminal lumbar interbody fusion (TLIF) for lumbar degenerative diseases.

METHODS

Up to September 2022, established electronic literature databases including PubMed, Web of Science, EMBASE, and the Cochrane Library were systematically searched. Randomized controlled trials (RCTs) published in English that compared the efficacy of UPSF versus BPSF in TLIF were included. The methodological quality was evaluated, relevant data was extracted, and suitable meta-analysis was carried out. Data of fusion rate, complications, cage migration, visual analog scale (VAS), and Oswestry Disability Index (ODI), total blood loss (TBL), operation time, and hospital stay were extracted and analyzed. Pooled mean differences and risk ratio (RR) along with 95% confidence intervals (95% CI) were calculated for the results.

RESULTS

Ten RCTs including 614 patients (UPSF = 294, BPSF = 320) were included in our meta-analysis. There were no significant differences in terms of fusion rate, VAS (VAS-BP and VAS-LP), ODI, complications, or hospital stay between UPSF and BPSF groups (P > 0.05, respectively). The UPSF group clearly had the advantage of less blood loss (SMD = -2.99, 95% CI [-4.54, -1.45], P = 0.0001) and operation time (SMD = -2.05, 95% CI [-3.10, -1.00], P = 0.0001). However, UPSF increased cage migration more than BPSF (10.7% vs 4.8%, RR = 2.23, 95% CI [1.07, 4.65],  P = 0.03).

CONCLUSION

According to the findings of this meta-analysis, UPSF is just as effective as BPSF in TLIF and may reduce blood loss and operation time. Nevertheless, UPSF may result in more cage migration than BPSF.

Comparison of the Unilateral and the Bilateral Pedicle Screw Fixation without Using an Interbody Cage: Randomized Clinical Trial

BACKGROUND: Lumbar spine instability is one of the main causes of low back pain and has become more prevalent in recent years. Bilateral pedicle screw fixation is used to perform posterior lumbar stabilization, which is complemented by the installation of an interbody cage. AIM: The aim of the study was evaluating of the results of unilateral and bilateral pedicle screw fixation without using of an interbody cage. METHODS: A prospective randomized study of 96 patients was carried out. Forty-seven patients were assigned to the group of the unilateral pedicle screw fixation versus 49 patients were moved to the group of the bilateral pedicle screw fixation of the lumbar spine. Of the 96 patients, 80 patients eventually were included in the study. However, seven patients in the first group and nine patients were lost to follow-up. Surgery timing, blood loss volume, clinical outcomes (scores on the Oswestry disability index [ODI], EQ-5D and visual analogue scale [VAS]) were evaluated in 6–12 months after surgical treatment. All the patients included in this study underwent functional and control computed tomography in 12 months after surgery. RESULTS: Both groups showed a significant improvement in VAS, EQ-5D, and ODI in 1 year after surgical treatment. The two groups significantly differed in the surgery timing (unilateral – 90.2 min; and bilateral – 129.4 min) and blood loss volume (unilateral – 152.7 ml; and bilateral – 230.1 ml), p < 0.05. CONCLUSIONS: Unilateral and bilateral pedicle screw fixation showed similar clinical results, while results in both types of fixation differed in slight manner. However, the duration of surgical treatment and intraoperative blood loss volume proved to be lower for the unilateral fixation group, which indicates that the use of the unilateral fixation can be the choice of performing posterior stabilization at a single-level instability of the spine without using an interbody cage.

Interspinous Process (ISP) Devices in Comparison to the Use of Traditional Posterior Spinal Instrumentation

A systematic literature review was conducted on studies comparing interspinous process (ISP) devices to traditional methods of posterior spinal instrumentation (pedicle screw-rod construct), in terms of indications of use, complications, pain assessment, estimated blood loss, length of hospital stay, reoperation rates, and return to work. The objective was to analyze, evaluate and summarize the current published literature on the proposed efficacy and clinical and surgical long-term outcomes of the ISP device in comparison to the traditional posterior spinal instrumentation (pedicle screw-rod construct). The ISP device is a minimally invasive and less disruptive alternative to traditional methods of posterior spinal instrumentation (pedicle screw-rod construct). However, very few published literature studies to date have reported the comparison of ISPs in terms of efficacy and clinical and surgical outcomes, to traditional posterior spinal instrumentation. A systematic literature review was performed in PubMed and Google Scholar to evaluate the results of published research that meet the defined inclusion and exclusion criteria and to analyze clinical indications and surgical outcomes of the ISP device compared to traditional methods of posterior spinal instrumentation (pedicle screw-rod construct). Inclusion criteria included keywords such as "ISP device, ISP, posterior spinal instrumentation, pedicle screw fixation, bilateral pedicle screws, interbody fusion with posterior spinal instrumentation, lumbar spinal stenosis, and posterior lumbar stability." No exclusion criteria keywords were included in this literature review. ISPs provide a high degree of spinal stability in multiple planes, including a decreased range of motion restriction in flexion-extension, and comparable results to bilateral pedicle screw (BPS) in axial rotation. The use of the ISP device in adjunct with an interbody fusion, ensures less estimated operative blood loss (EBL), shorter operative time, less bony exposure without the need for extensive soft tissue or muscle retraction, a decrease in the rate of pseudoarthrosis, and a shorter length of hospital stay (LOHS) when compared to the traditional posterior instrumentation (pedicle screw-rod construct). Based on the various published literature reviews noted throughout this research paper, it is safe to conclude, that an ISP device that is accompanied by interbody fusion, including posterior approaches posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF); anterior approaches such as anterior interbody fusion (ALIF), and lateral approaches including direct lateral interbody fusion (DLIF), lateral lumbar interbody fusion (LLIF), extreme lateral interbody fusion (XLIF), is considered a credible and an effective minimally invasive option for the treatment of mild to moderate lumbar stenosis and stable low-grade spondylolisthesis (less than two) when compared to the traditional posterior spinal instrumentation of a pedicle screw-rod construct. Surgeons that are relatively new to the ISP technologies for spinal instrumentation would likely benefit from more clinical and surgical evidence of safety and efficacy in published peer-reviewed medical literature. Further clinical trials are needed to manifest the efficacy of ISPs regarding postoperative outcomes when compared to traditional posterior instrumentation techniques (pedicle screw-rod construct) with adjunct interbody fusions.

Unilateral versus bilateral pedicle screw fixation in lumbar fusion: A systematic review of overlapping meta-analyses

OBJECTIVES

To carry out a systematic review on the basis of overlapping meta-analyses that compare unilateral with bilateral pedicle screw fixation (PSF) in lumbar fusion to identify which study represents the current best evidence, and to provide recommendations of treatment on this topic.

METHODS

A comprehensive literature search in PubMed, Embase, and the Cochrane Library databases was conducted to identify meta-analyses that compare unilateral with bilateral PSF in lumbar fusion. Only meta-analyses exclusively covering randomized controlled trials were included. Study quality was evaluated using the Oxford Levels of Evidence and Assessment of Multiple Systematic Reviews (AMSTAR) instrument. Then, the Jadad decision algorithm was applied to select the highest-quality study to represent the current best evidence.

RESULTS

A total of 9 studies with Level II of evidence fulfilled the eligibility criteria and were included. The scores of AMSTAR criteria for them varied from 5 to 9 (mean 7.78). The current best evidence detected no significant differences between unilateral and bilateral PSF for short-segment lumbar fusion in the functional scores, length of hospital stay, fusion rate, and complication rate. However, unilateral PSF involved a remarkable decrease in operative time and blood loss but increase of cage migration when compared with bilateral PSF.

CONCLUSIONS

According to this systematic review, unilateral PSF is an effective method of fixation for short-segment lumbar fusion, has the advantages of reduced operative time and blood loss over bilateral PSF, but increases the risk of cage migration.

Comparison of unilateral pedicle screw fixation and interbody fusion with PEEK cage vs. standalone expandable fusion cage for the treatment of unilateral lumbar disc herniation

INTRODUCTION

This study was conducted to compare the clinical effects of unilateral pedicle screw fixation and interbody fusion with PEEK cage (UPSFC) and standalone expandable fusion cage (SAEFC) on unilateral lumbar disc herniation.

MATERIAL AND METHODS

From September 2011 to July 2014, a respective investigation was performed on 130 lumbar disc herniation patients treated with SAEFC or UPSFC. The hospital stay, operating time, blood loss, Japanese orthopaedic association scores (JOA), and visual analogue score (VAS) in the two groups were compared using Student's t-test.

RESULTS

The average of follow-up time was 25.6 ±6.4 and 25.2 ±5.8 months, respectively. No significant difference in the postoperative hospitalizsation, intraoperative blood loss, operative time, and postoperative fusion rate was detected between the two groups. VAS score in the UPSFC group was significantly lower than in the SAEFC group at 6 and 12 months after operation (p = 0.014, p = 0.004). X-ray images indicated that the subsidence rate was 8.1% (5/62) in the SAEFC group, while no subsidence was detected in UPSFC group 12 month after operation.

CONCLUSIONS

Both SAEFC and UPSFC are effective techniques. UPSFC may be a better choice for patients with lumbar disc herniation and unilateral limb symptoms of nerve root in view of the advantages of better low back pain relief and low subsidence rate.

Effectiveness and safety of unilateral pedicle screw fixation in transforaminal lumbar interbody fusion (TLIF): a systematic review and meta-analysis

PURPOSE

To evaluate the effectiveness and safety of unilateral pedicle screw fixation in transforaminal lumbar interbody fusion (TLIF) by comparing with bilateral pedicle screw fixation.

MATERIALS AND METHODS

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trial database were used to search and identify clinical prospective trials that evaluated the efficacy and safety of unilateral fixation as compared with bilateral fixation in TLIF surgery. The methodological qualities of studies were assessed using the PEDro (Physiotherapy Evidence Database) score and Newcastle-Ottawa Scale.

RESULTS

Fourteen prospective studies comprising 954 participants were analyzed. Data synthesis show lower fusion rate (P = 0.03) and more cage migration (P = 0.04) in unilateral group compared to bilateral group. There was no significant difference in visual analog scale (VAS), Oswestry Disability Index (ODI), the Short Form 36 Health Survey (SF-36) physical component score (PCS), and length of hospital stay between unilateral and bilateral groups. The unilateral group had shorter operative time (P < 0.00001) and less blood loss (P = 0.0007).

CONCLUSIONS

Based on this systematic review and meta-analysis, the unilateral fixation in TLIF may achieve a similar clinical outcome and reduce blood loss and operative time when compared with that in bilateral fixation. However, the unilateral fixation may produce lower fusion rate and more cage migration than bilateral fixation in TLIF.

Anterograde Fixation Module for Posterior Acetabular Column Fracture: Computer-Assisted Determination of Optimal Entry Point, Angle, and Length for Screw Insertion

BACKGROUND The aim of this study was to provide valid data for a plate-screw fixation model for fractured posterior-anterior columns of the acetabulum. MATERIAL AND METHODS Nineteen cadaveric bony hemi-pelvis specimens were obtained and 50 healthy adults were enrolled. The modified Stoppa approach and computed tomography (CT) imaging were used to collect the measured parameter data of the module. RESULTS The measured parameter data were as follows: OP, 0.96±0.32 cm in females and 0.92±0.16 cm in males (P>0.05); PI, 0.98±0.28 cm in females, and 0.75±0.23 cm in males (P>0.05); Ðϴ, 59.68°±6.28° in females and 56.75°±3.22° in males (P>0.05); and Ðφ, 41.27°±2.76° in females and 34.31°±2.78° in males (P<0.05). The corresponding CT image data were as follows: PI, 1.08±0.22 cm in females and 0.85±0.27 cm in males (P>0.05); OP, 1.06±0.29 cm in females and 1.12±0.24 cm in males (P>0.05); Ðϴ, 55.33°±4.00° in females and 55. 50°±3.43° in males (P>0.05); and Ðφ was 39.21°±2.45°in females and 35.58°±2.31°in males (P<0.05). No significant difference with respect to sex and side existed between specimens and healthy adults (P>0.05). CONCLUSIONS The measured parameter data obtained in healthy adults and cadaveric specimens provided an anatomic basis for the designation of the guide module, and thus confirmed the accuracy and safety of screw placement in fractured columns of the acetabulum.

Comparing Single Versus Double Screw-Rod Anterior Instrumentation for Treating Thoracolumbar Burst Fractures with Incomplete Neurological Deficit: A Prospective, Randomized Controlled Trial

Background

Following a thoracolumbar burst fracture (TCBF), anterior screw-rods apply pressure upon the graft site. However, there is limited evidence comparing single screw-rod anterior instrumentation (SSRAI) to double screw-rod anterior instrumentation (DSRAI) for TCBFs. Our objective was to compare SSRAI versus DSRAI for TCBFs with incomplete neurological deficit.

Material/Methods

A total of 51 participants with T11-L2 TCBFs (AO classification: A3) were randomly assigned to receive SSRAI or DSRAI. Key preoperative, perioperative, and postoperative data were collected. Statistical analysis was conducted to determine the independent factors associated with inferior clinical outcomes, as well as the comparative efficacy of SSRAI and DSRAI.

Results

There were no significant differences in the key demographic and clinical characteristics between the two groups (all p>0.05). Smoking status was significantly associated with inferior three-month and six-month Denis pain scores (Wald statistic=4.246, p=0.039). Both SSRAI and DSRAI were significantly effective in improving three-month and six-month postoperative degree of kyphosis, three-month and six-month postoperative ASIA impairment scale scores, three-month and six-month postoperative Denis pain score, and three-month and six-month postoperative Denis work score (all p<0.001). Although there were no significant differences between DSRAI and SSRAI with respect to all outcomes (all p>0.05), DSRAI displayed significantly longer operating times, as well as significantly larger operative blood losses (both p<0.001).

Conclusions

SSRAI may be preferable over DSRAI for TCBFs with incomplete neurological deficit due to its lower operating time and amount of operative blood loss.

Unilateral Pedicle Screw Fixation with Bone Graft vs. Bilateral Pedicle Screw Fixation with Bone Graft or Cage: A Comparative Study

BACKGROUND

The aim of this study was to explore the clinical efficacy of unilateral pedicle screw fixation with bone graft (UPSFB) in treating single-segment lumbar degenerative diseases (LDD), as compared to bilateral pedicle screw fixation with bone graft (BPSFB) or with cage (BPSFC).

MATERIAL/METHODS

Medical records were retrospectively collected between 01/2010 and 02/2015 in Longyao County Hospital. According to surgical methods used, all patients were divided into 3 groups: UPSFB group, BPSFB group, and BPSFC group. Clinical outcomes were evaluated by blood loss, blood transfusion, duration of operation, hospital stay, postoperative complications, interbody fusion rate, reoperation rate, medical expenses, patient satisfaction survey, and JOA score.

RESULTS

Ninety-five patients were included and underwent 2.5-year follow-up, with 7 patients lost to regular follow-up. As compared to the BPSFB group and BPSFC group, the UPSFB group had less blood loss and less blood transfusion, as well as shorter hospital stay (p<0.05). Medical expenses were far lower in the UPSFB group (p<0.001). There were no significant differences among the 3 groups in postoperative complications, interbody fusion rate, reoperation rate, JOA score, and patient satisfaction (all p>0.05).

CONCLUSIONS

As compared to BPSFB and BPSFC, UPSFB has the same reliability and effectiveness in treating single-segment LDD with unilateral radicular symptoms in a single lower extremity, with the additional advantage being less expensive.

Minimally Invasive Unilateral vs. Bilateral Pedicle Screw Fixation and Lumbar Interbody Fusion in Treatment of Multi-Segment Lumbar Degenerative Disorders

Background

The choice for instrumentation with minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in treatment of degenerative lumbar disorders (DLD) remains controversial. The goal of this study was to investigate clinical outcomes in consecutive patients with multi-segment DLD treated with unilateral pedicle screw (UPS) vs. bilateral pedicle screw (BPS) instrumented TLIF.

Material/Methods

Eighty-four consecutive patients who had multi-level MIS-TLIF were retrospectively reviewed. All data were collected to compare the clinical outcomes between the 2 groups.

Results

Both groups showed similar clinical function scores in VAS and ODI. The two groups differed significantly in operative time (P<0.001), blood loss (P<0.001), and fusion rate (P=0.043), respectively.

Conclusions

This study demonstrated similar clinical outcomes between UPS fixation and BPS procedure after MIS-TLIF for multi-level DLD. Moreover, UPS technique was superior in operative time and blood loss, but represented lower fusion rate than the BPS construct did.