Anatomische Reposition und monosegmentale Fusion bei hochgradiger dysplastischer Spondylolisthese L5/S1

[Surgical treatment of high-grade spondylolisthesis]

OBJECTIVE

Establishment of a physiological profile of the spine via reduction of the kyphotic slipped vertebra in the transverse and sagittal planes. Achieving solid fusion. Improvement of preoperative pain symptoms and prevention or elimination of neurological deficits.

INDICATIONS

High-grade spondylolisthesis (Meyerding grade 3 and 4) as well as spondyloptosis after conservative treatment and corresponding symptoms. Serious neurological deficits, hip-lumbar extensor stiffness, are emergency indications.

CONTRAINDICATIONS (CI)

Individual risk assessment must be made. Absolute CI are infections with the exception of serious neurological deficits. Multiple abdominal operations or interventions on the large vessels can be a relative contraindication for ventral intervention.

SURGICAL TECHNIQUE

For spondylolistheses of grade 3 according to Meyerding, we recommend a one-stage dorso-ventro-dorsal procedure with radicular decompression, correction and fusion in the index segment. From grade 4 according to Meyerding, reduction of the fifth lumbar vertebral body in the index segment L5/S1 is preceded by resection of the sacral dome. In cases of spondyloptosis, a two-stage procedure is often indicated. In this case, a screw-rod system spanning the index segment is implanted in the first step, which is used to distract the index segment for several days. Ventrodorsal reduction is performed in the second step.

POSTOPERATIVE MANAGEMENT

Axis-appropriate full mobilization from postoperative day 1. We recommend a light diet until the first defecation. Dorsal suture removal after 12 days if the wound is dry and free of irritation. Lifting and carrying heavy loads and also competitive or contact sports should be avoided for 12 weeks.

RESULTS

From January 2000 to December 2020, a total of 43 patients with high-grade spondylolisthesis were treated in our clinic in the manner described. The Numeric Rating Scale (NRS) and the Oswestry Disability Index (ODI) improved significantly during the observation period of 3 months and 1 year. The 1‑year radiological data in 28 of the 36 patients showed complete reduction of the slipped vertebra, in 6 grade 1, and in 2 patients grade 2 according to Meyerding. Also, the kyphosis of the index vertebra was significantly corrected from a mean of 15° (0-52°) preoperatively to a lordotic profile of a mean of 4° (0-11°). No complications requiring revision were observed. One patient with preoperative cauda equina syndrome was left with right radicular sensorimotor S1 syndrome.

Surgical outcomes with anatomic reduction of high-grade spondylolisthesis revisited: an analysis of 101 patients

OBJECTIVE

The ideal strategy for high-grade L5-S1 isthmic spondylolisthesis (HGS) remains controversial. Critical questions include the impact of reduction on clinical outcomes, rate of pseudarthrosis, and postoperative foot drop. The scope of this study was to delineate predictors of radiographic and clinical outcome factors after surgery for HGS and to identify risk factors of foot drop.

METHODS

This was a single-center analysis of patients who were admitted for HGS, defined as grade III or greater L5 translation according to the Meyerding (MD) classification. Complete postoperative reduction was defined as MD grade I or less and L5 slip < 20%. Forty-six patients completed health-related quality-of-life questionnaires (Oswestry Disability Index, Physical Component Summary of SF-36, and visual analog scale) and ≥ 2 years' follow-up (average 105 months). A 540° approach was used in 61 patients, a 360° approach was used in 40, and L5 corpectomy was used in 17. Radiographic analysis included measures of global spinopelvic balance (e.g., pelvic incidence [PI], lumbar lordosis) and measurement of lumbosacral kyphosis angle (LSA), L4 slope (L4S), L5 slip (%), and postoperative increase of L5-S1 height.

RESULTS

The authors included 101 patients with > 1 year of clinical and radiographic follow-up. The mean age was 26 years. Average preoperative MD grade was 3.8 and average L5 slip was 81%; complete reduction was achieved in 55 and 42 patients, respectively, according to these criteria. At follow-up, LSA correlated with all clinical outcomes (r ≥ 0.4, p < 0.05). Forty patients experienced a major complication. Risk was increased in patients with greater preoperative deformity (i.e., LSA) (p = 0.04) and those who underwent L5 corpectomy (p < 0.01) and correlated with greater deformity correction. Thirty-one patients needed revision surgery, including 17 for pseudarthrosis. Patients who needed revision surgery had greater preoperative deformity (i.e., MD grade and L5 slip) (p < 0.01), greater PI (p = 0.02), and greater postoperative L4S (p < 0.01) and were older (p = 0.02), and these patients more often underwent L5 corpectomy (p < 0.01). Complete reduction was associated with lower likelihood of pseudarthrosis (p = 0.08) and resulted in better lumbar lordosis correction (p = 0.03). Thirty patients had foot drop, and these patients had greater MD grade and L5 slip (p < 0.01) and greater preoperative LSA (p < 0.01). These patients with foot drop more often required L5 corpectomy (p < 0.01). Change in preoperative L4S (p = 0.02), LSA (p < 0.01), and L5-S1 height (p = 0.02) were significantly different between patients with foot drop and those without foot drop. A significant risk model was established that included L4S change and PI as independent variables and foot drop as a dependent variable (82% negative predictive value and 71% positive predictive value, p < 0.01).

CONCLUSIONS

Multivariable analysis identified factors associated with foot drop, major complications, and need for revision surgery, including degree of deformity (MD grade and L5 slip) and correction of LSA. Functional outcome correlated with LSA correction.

[Spondylolisthesis in the growing spine]

BACKGROUND

Spondylolisthesis (Greek for sliding vertebra) in children is usually the result of a defect (=lysis) or an elongation of the interarticular portion. The cause can be a congenital dysplasia of the dorsal stabilizing structures or pressure of the facet on the interarticular portion. This is a consequence of lumbar lordosis which is necessary for an upright posture.

TREATMENT

The treatment depends on the symptoms and the risk of progression. This is related to the sliding distance, the degree of secondary dysplasia of the vertebral bodies and the sagittal profile, which is considered in the Mac-Thiong classification. For low-grade olistheses, conservative therapy is an option; for a symptomatic lysis without disc degeneration, pars repair should be considered. In higher-grade olistheses, repositioning and spondylodesis are usually recommended. Repositioning improves the fusion rate and sagittal profile, but increases the risk of nerve root damage, so complete repositioning should not be forced.

Reduction and monosegmental fusion for lumbar spondylolisthesis with a long tab percutaneous pedicle screw system: "swing" technique

OBJECTIVEWith the development of minimally invasive procedures, percutaneous pedicle screw systems have been used to attempt to correct spondylolisthesis. No previous studies have reported on reduction measures using long tab percutaneous pedicle screws for spondylolisthesis. Additional intraoperative correction has been proposed with the "swing" technique. This study was conducted to compare the efficacy of standard minimally invasive transforaminal interbody fusion (MIS-TLIF) with the efficacy of MIS-TLIF with the "swing" technique (MIS-TLIF and swing) in lumbar spondylolisthesis.METHODSThis was a matched-control study and included 30 consecutive patients who were followed up for 6 months after surgery. Of those patients, 15 were treated with operative reduction via MIS-TLIF with the "swing" technique, whereas the other 15 were treated with the standard MIS-TLIF procedure. The swing technique is a new reduction procedure for use with long tab percutaneous screws. In the swing technique, the entire system is swung back and forth several times after all constructs are placed. Only patients with Meyerding grade I or II lumbar spondylolisthesis were included in the study (18 with grade I and 12 with grade II). Perioperative and clinical outcomes, radiological parameters (Meyerding grade, percentage of slip, slip correction rate, segmental lordosis, and lumbar lordosis) were compared between groups at 6 months after surgery.RESULTSDemographic data did not differ significantly between the 2 groups. Postoperative clinical outcomes showed significant improvement in both groups. Postoperative radiological parameters showed that the degree of spondylolisthesis (swing: 4.7% vs standard: 8.9%) and reduction rate (swing: 77.3% vs standard: 57.1%) favored the swing group. The swing technique effectively decreased the degree of spondylolisthesis (swing: 24.1% to 4.7% vs standard: 21.8% to 8.9%). No complications related to the procedure were reported.CONCLUSIONSMIS-TLIF with the "swing" technique with long tab percutaneous pedicle screws is a safe and effective reduction method for monosegmental spondylolisthesis. This technique cannot only alleviate symptoms but also achieve nearly completely reduction of slippage.

Posterior reduction and monosegmental fusion with intraoperative three-dimensional navigation system in the treatment of high-grade developmental spondylolisthesis

Background:

The treatment of high-grade developmental spondylolisthesis (HGDS) is still challenging and controversial. In this study, we investigated the efficacy of the posterior reduction and monosegmental fusion assisted by intraoperative three-dimensional (3D) navigation system in managing the HGDS.

Methods:

Thirteen consecutive HGDS patients were treated with posterior decompression, reduction and monosegmental fusion of L5/S1, assisted by intraoperative 3D navigation system. The clinical and radiographic outcomes were evaluated, with a minimum follow-up of 2 years. The differences between the pre- and post-operative measures were statistically analyzed using a two-tailed, paired t-test.

Results:

At most recent follow-up, 12 patients were pain-free. Only 1 patient had moderate pain. There were no permanent neurological complications or pseudarthrosis. The magnetic resonance imaging showed that there was no obvious disc degeneration in the adjacent segment. All radiographic parameters were improved. Mean slippage improved from 63.2% before surgery to 12.2% after surgery and 11.0% at latest follow-up. Lumbar lordosis changed from preoperative 34.9 ± 13.3° to postoperative 50.4 ± 9.9°, and 49.3 ± 7.8° at last follow-up. L5 incidence improved from 71.0 ± 11.3° to 54.0 ± 11.9° and did not change significantly at the last follow-up 53.1 ± 15.4°. While pelvic incidence remained unchanged, sacral slip significantly decreased from preoperative 32.7 ± 12.5° to postoperative 42.6 ± 9.8°and remained constant to the last follow-up 44.4 ± 6.9°. Pelvic tilt significantly decreased from 38.4 ± 12.5° to 30.9 ± 8.1° and remained unchanged at the last follow-up 28.1 ± 11.2°.

Conclusions:

Posterior reduction and monosegmental fusion of L5/S1 assisted by intraoperative 3D navigation are an effective technique for managing high-grade dysplastic spondylolisthesis. A complete reduction of local deformity and excellent correction of overall sagittal balance can be achieved.

Correlation of reduction and clinical outcome in patients with degenerative spondylolisthesis

STUDY DESIGN

Prospective cohort study.

INTRODUCTION

Operative treatment is increasingly implemented for the treatment of degenerative lumbar listhesis, with lumbar fusion the most common intervention. Prediction of clinical outcomes after such procedures is of ongoing relevance, and the correlation of radiologic parameters with clinical outcome remains controversial. In particular, clinical studies have not determined conclusively whether reduction of slipped vertebrae is beneficial.

METHODS

We performed a monocenter prospective analysis of a comprehensive set of quality of life scores (QLS) (Core Outcome Measure Index, Oswestry Low Back Pain Disability Index, SF-36) of 40 patients, who underwent a standardized PLIF procedure for symptomatic, Spondylolisthesis. Follow-up was 24 months. The correlations between the radiologic parameters (degree of slippage, sagittal rotation) and the clinical scores before surgery as well as 12 and 24 months post-operatively were examined.

RESULTS

All QLS showed a statistically significant improvement after 12 and 24 months post-operatively (p < 0.05). The mean amount of the anterior slippage was 34.2 ± 14.7 % (minimum 12 %, maximum 78 %). After 12 months, there was an average 19.1 % decrease to 15.1 ± 8.3 % (minimum 2 %, maximum 38 %, p < 0.000) and after 24 months it was decreased by 18.0-16.2 ± 9.0 % (minimum 2.9 %, maximum 40 %, p < 0.000). Average sagittal rotation measured 67.3° ± 16.6° initially (minimum 35°, maximum 118) and decreased by 4.3° to an average of 63.0° ± 15.2° at 12 months post-surgery (minimum 15°, maximum 101°, p = 0.065,), and by 5.7° to an average of 61.6° ± 13.0° at 24 months (minimum 15°, maximum 90°, p = 0.044). The data show positive correlations between the amount of reduction of the slipped vertebra as well as the amount of correction of the sagittal rotation and the improvement of the clinical outcomes(r = 0.31-0.54, p < 0.05).

CONCLUSION

The current study indicates a modest advantage for the best possible reposition in respect of the clinical outcome.

[Pathophysiology, neurology and diagnostic radiology of degenerative diseases of the lumbar spine]

Degenerative diseases of the lumbar spine have a high medical and socioeconomic impact. The leading symptom is back pain, but there are many reasons for this. The aim of this paper is to describe the pathogenesis of degenerative diseases of the lumbar spine and their clinical symptoms in relation to the functional anatomy and biomechanics of the spine. Discs, vertebral facet joints, osseous and ligamentous structures as well as the erector trunci muscles are a functional unit. Progressive degenerative changes of the discs induce bone overgrowth and ligamentous thickening, affect the orientation of the vertebral facet joints and change the pressure, tension and shear forces of the spine. The different radiological diagnostic tools are presented and discussed according to the different degenerative diseases of the lumbar spine.