Lumbar Dynamic Stabilization With 2-Stage Surgery: Early Results

Two-Stage Lumbar Dynamic Stabilization Surgery: A Comprehensive Analysis of Screw Loosening Rates and Functional Outcomes Compared to Single-Stage Approach in Osteopenic and Osteoporotic Patients

BACKGROUND

Dynamic lumbar stabilization aims to preserve spinal movement, offering stability and controlled motion. However, screw loosening, especially in patients with osteopenia and osteoporosis, remains challenging.

METHOD

Between 2018 and 2022, a retrospective analysis was conducted on a total of 119 patients diagnosed with osteopenia and osteoporosis who underwent spinal dynamic instrumentation surgery. These patients were categorized into two groups: single-stage surgery (n = 67) and two-stage surgery (n = 52). Over the 48-month follow-up period, the occurrence and percentage of screw loosening were examined at each surgical level per patient, as well as by screw location (pedicular, corpus, tip). Clinical outcomes were evaluated using Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores.

RESULTS

Total screw loosening rates were significantly lower in the two-stage group (2.83%) compared to the single-stage group (14.63%, p < 0.001). Patient-based loosening occurred in 5 patients (9.6%) in the two-stage group and 16 patients (23.9%) in the single-stage group. Loosening rates were lower in the two-stage group at L2 (7.78%, p = 0.040), L3 (5.56%, p < 0.001), L4 (8.89%, p = 0.002), and L5 (10.00%, p = 0.006), but higher at S1 (21.11%, p = 0.964), T12 (15.56%, p = 0.031), and iliac levels (15.56%, p = 0.001). Pedicular section exhibited the highest loosening (37 cases). VAS and ODI scores improved significantly in both groups, with better outcomes in the two-stage group at the 48. months (p < 0.001).

CONCLUSIONS

The two-stage surgical approach significantly reduces screw loosening in patients with osteopenia and osteoporosis undergoing dynamic stabilization surgery, offering enhanced stability and better clinical outcomes.

Can Dynamic Spinal Stabilization Be an Alternative to Fusion Surgery in Adult Spinal Deformity Cases?

BACKGROUND

Rigid stabilization and fusion surgery are widely used for the correction of spinal sagittal and coronal imbalance (SCI). However, instrument failure, pseudoarthrosis, and adjacent segment disease are frequent complications of rigid stabilization and fusion surgery in elderly patients. In this study, we present the results of dynamic stabilization and 2-stage dynamic stabilization surgery for the treatment of spinal SCI. The advantages and disadvantages are discussed, especially as an alternative to fusion surgery.

METHODS

In our study, spinal, sagittal, and coronal deformities were corrected with dynamic stabilization performed in a single session in patients with good bone quality (without osteopenia and osteoporosis), while 2-stage surgery was performed in patients with poor bone quality (first stage: percutaneous placement of screws; second stage: placement of dynamic rods and correction of spinal SCI 4-6 months after the first stage). One-stage dynamic spinal instrumentation was applied to 20 of 25 patients with spinal SCI, and 2-stage dynamic spinal instrumentation was applied to the remaining 5 patients.

RESULTS

Spinal SCI was corrected with these stabilization systems. At 2-year follow-up, no significant loss was observed in the instrumentation system, while no significant loss of correction was observed in sagittal and coronal deformities.

CONCLUSION

In adult patients with spinal SCI, single or 2-stage dynamic stabilization is a viable alternative to fusion surgery due to the very low rate of instrument failure.

CLINICAL RELEVANCE

This study questions the use of dynamic stabilization systems for the treatment of adult degenerative deformities.

LEVEL OF EVIDENCE: 4

Use of Dynamic Spinal Instruments (Dynesys) in Adult Spinal Deformities According to Silva-Lenke and Berjano-Lamartina Classifications

BACKGROUND

Adult spinal deformities (ASD) present complex challenges in spine surgery. The diverse nature of these deformities requires a comprehensive understanding of their classification and treatment options. Traditional approaches, such as fusion and rigid stabilization are associated with complications, including screw loosening, breakage, proximal junctional kyphosis (PJK), and pseudoarthrosis. Dynamic stabilization techniques have emerged as promising alternatives, to reduce these complications and preserve spinal motion.

OBJECTIVE

This study investigated the effectiveness of dynamic stabilization using the Dynesys system in the surgical treatment of adult degenerative spinal deformities, with a particular emphasis on their classification.

METHODS

ASDs were classified according to the Berjano-Lamartina (BL) and Silva-Lenke (SL) classifications. We analyzed the efficacy of the Dynesys system in enhancing sagittal balance, radiological parameters, and clinical outcomes in this context.

RESULTS

Dynamic stabilization of patients with ASDs using the Dynesys system significantly improved the visual analog scale and Oswestry Disability Index scores and decreased the complication rates. Patients with BL types 2, 3, and 4 experienced a significant improvement in sagittal balance followed by sagittal vertical axis measurements (p = 0.045, p = 0.015, and p < 0.0001, respectively).

CONCLUSION

The SL and BL classifications, which were originally developed for rigid spinal stabilization, can be applied in dynamic stabilization. Furthermore, dynamic stabilization using the Dynesys system can be used as an alternative to rigid stabilization in SL levels 2 and 3, and BL types 1, 2, and 3, and in some patients with type 4 ASDs.

Clinical and radiological analysis of the effects of three different lumbar transpedicular dynamic stabilization system on disc degeneration and regeneration

Objective

This study aims to assess the clinical outcomes of three transpedicular dynamic systems in treating degenerative disc disease and evaluate their impact on both clinical and radiological aspects of the operated and adjacent segments.

Materials and methods

A total of 111 patients who underwent posterior transpedicular short-segment dynamic system procedures for treatment of degenerative disc disease were included. The patients were categorized into three groups, namely, Group 1 (Dynesys system, n = 38), Group 2 (Safinaz screw + PEEK rod, n = 37), and Group 3 (Safinaz screw + titanium rod, n = 36). Disc regeneration in the operated segment and disc degeneration in the operated, upper, and lower adjacent segments were assessed using the Pfirrmann Classification.

Results

Postoperatively, a statistically significant difference was observed in visual analog scale and Oswestry Disability Index scores (p < 0.001). However, no statistically significant difference was seen in disc degeneration/regeneration and degeneration scores of the upper and lower adjacent segments between the preoperative and postoperative groups (p = 0.763, p = 0.518, p = 0.201). Notably, a positive effect on disc regeneration at the operated level (32.4%) was observed. No significant differences were found between the groups in terms of operation rates, screw loosening, and screw breakage after adjacent segment disease (p > 0.05).

Conclusion

In patients without advanced degeneration, all three dynamic systems demonstrated the ability to prevent degeneration in the adjacent and operated segments while promoting regeneration in the operated segment. Beyond inhibiting abnormal movement in painful segments, maintaining physiological motion and providing axial distraction in the operated segment emerged as key mechanisms supporting regeneration.

Foraminoplasty with Partial Pediculectomy in Degenerative Spondylolisthesis Cases with Nerve Compression

BACKGROUND

Degenerative spondylolisthesis refers to a forward displacement of a vertebra relative to the underlying vertebra. Patients with radicular pain and/or neurogenic claudication are considered suitable candidates for surgical intervention. The aim of this study was to present clinical results of dynamic stabilization applied after pediculectomy and neural foramen enlargement in patients with degenerative spondylolisthesis and normal spinal sagittal balance.

MATERIALS AND METHODS

All patients who underwent pediculectomy and dynamic stabilization for lumbar degenerative spondylolisthesis were retrospectively identified. Diagnosis was made with detailed neurological and radiological imaging examinations for the anatomical location of the pain. Demographic data, visual analog scale scores, and quality-of-life scores were obtained.

RESULTS

Patients included 3 (33.3%) men and 6 (66.7%) women with a mean age of 61.3 ± 13.0 years (range, 46-80 years) at initial symptom onset. Grade 1 degenerative spondylolisthesis was present in 5 (55.6%) patients, and grade 2 was present in 4 (44.4%) patients. Pathology was detected in L4-5 in 4 patients (44.4%) and L5-S1 in 5 patients (55.6%). In all patients, at the 3-month follow-up, statistically significant decrease in visual analog scale and Oswestry Disability Index scores was observed. At the last follow-up, no implant-related complications requiring revision were observed.

CONCLUSIONS

In patients without any pathology in the sagittal balance, the optimal physiological treatment modality can be created by applying posterior dynamic stabilization together with pediculectomy to support the posterior tension band.