Is it possible to preserve lumbar lordosis after hybrid stabilization? Preliminary results of a novel rigid–dynamic stabilization system in degenerative lumbar pathologies

Purpose of the study

To evaluate the results of a novel rigid–dynamic stabilization technique in lumbar degenerative segment diseases (DSD), expressly pointing out the preservation of postoperative lumbar lordosis (LL).

Materials and methods

Forty-one patients with one level lumbar DSD and initial disc degeneration at the adjacent level were treated. Circumferential lumbar arthrodesis and posterior hybrid instrumentation were performed to preserve an initial disc degeneration above the segment that has to be fused. Clinical and spino-pelvic parameters were evaluated pre- and postoperatively.

Results

At 2-year follow-up, a significant improvement of clinical outcomes was reported. No statistically significant difference was noted between postoperative and 2-year follow-up in LL and in disc/vertebral body height ratio at the upper adjacent fusion level.

Conclusions

When properly selected, this technique leads to good results. A proper LL should be achieved after any hybrid stabilization to preserve the segment above the fusion.

     

The Utility of Local Anesthesia for Neurosurgical Interventions in a Low-Resource Setting: A Case Series

Introduction

Trauma is a major contributor to global morbidity and mortality, and injury to the central nervous system is the most common cause of death in these patients. While the provision of surgical services is being recognized as essential to global public health efforts, specialty areas such as neurosurgery remain overlooked.

Method

This is a retrospective case review of patients with operable lesions, such as extra-axial hematomas and unstable depressed skull fractures that underwent neurosurgical interventions under local anesthesia.

Results

A total of 13 patients underwent neurosurgical intervention under local anesthesia. Two and three patients with burr hole decompression of epidural and subdural hematomas, respectively; seven patients had elevation of depressed skull fractures and lastly one patient had an aspiration of a brain abscess. All patients survived with and without residual neurological deficits.

Conclusion

Access to resources and staff required to deliver general anesthesia is challenging in resource-poor settings. We have therefore begun performing emergent interventions under local anesthesia, with or without conscious sedation. While some patients had some minor residual weakness after the procedure, the degree of neurological deficit was improved from that observed before the procedure in all patients.

     

Does hybrid fixation prevent junctional disease after posterior fusion for degenerative lumbar disorders? A minimum 5-year follow-up study

Purpose

Medium- to long-term retrospective evaluation of clinical and radiographic outcome in the treatment of degenerative lumbar diseases with hybrid posterior fixation.

Methods

Thirty patients were included with the mean age of 47.8 years (range 35 to 60 years). All patients underwent posterior lumbar instrumentation using hybrid fixation for lumbar stenosis with instability (13 cases), degenerative spondylolisthesis Meyerding grade I (6 cases), degenerative disc disease of one or more adjacent levels in six cases and mild lumbar degenerative scoliosis in five patients. Clinical outcomes were evaluated using Oswestry disability index (ODI), Roland and Morris disability questionnaire (RMDQ), and the visual analog scale (VAS) pain scores. All patients were assessed by preoperative, postoperative and follow-up standing plain radiographs and lateral X-rays with flexion and extension. Adjacent disc degeneration was also evaluated by magnetic resonance imaging (MRI) at follow-up.

Results

At a mean follow-up of 6.1 years, we observed on X-rays and/or MRI 3 cases of adjacent segment disease (10.0 %): two of them (6.6 %) presented symptoms and recurred a new surgery. The last patient (3.3 %) developed asymptomatic retrolisthesis of L3 not requiring revision surgery. The mean preoperative ODI score was 67.6, RMDQ score was 15.1, VAS back pain score was 9.5, and VAS leg pain score was 8.6. Postoperatively, these values improved to 28.1, 5.4, 3.1, and 2.9, respectively, and remained substantially unchanged at the final follow-up: (27.7, 5.2, 2.9, and 2.7, respectively).

Conclusions

After 5-year follow-up, hybrid posterior lumbar fixation presented satisfying clinical outcomes in the treatment of degenerative disease.

     

Minimally invasive spine surgery in lumbar spondylodiscitis: a retrospective single-center analysis of 67 cases

Background

Minimally invasive surgical techniques have been developed to minimize tissue damage, reduce narcotic requirements, decrease blood loss, and, therefore, potentially avoid prolonged immobilization. Thus, the purpose of the present retrospective study was to assess the safety and efficacy of a minimally invasive posterior approach with transforaminal lumbar interbody debridement and fusion plus pedicle screw fixation in lumbar spondylodiscitis in comparison to an open surgical approach. Furthermore, treatment decisions based on the patient´s preoperative condition were analyzed.

Methods

67 patients with lumbar spondylodiscitis treated at our department were included in this retrospective analysis. The patients were categorized into two groups based on the surgical procedure: group (MIS) minimally invasive lumbar spinal fusion (n = 19); group (OPEN) open lumbar spinal fusion (n = 48). Evaluation included radiological parameters on magnetic resonance imaging (MRI), laboratory values, and clinical outcome.

Results

Preoperative MRI showed higher rates of paraspinal abscess (35.5 vs. 5.6%; p = 0.016) and multilocular location in the OPEN group (20 vs. 0%, p = 0.014). Overall pain at discharge was less in the MIS group: NRS 2.4 ± 1 vs. NRS 1.6 ± 1 (p = 0.036). The duration of hospital stay was longer in the OPEN than the MIS group (19.1 ± 12 days vs. 13.7 ± 5 days, p = 0.018).

Conclusion

The open technique is effective in all varieties of spondylodiscitis inclusive in epidural abscess formation. MIS can be applied safely and effectively as well in selected cases, even with epidural abscess.

     

The effect of an increased pulse width on the pattern of motor response (unilateral <Emphasis Type="Italic">versus</Emphasis> bilateral) during the Tsui test in labouring parturients: a randomized crossover trial

Background and objectives

The typical response to the Tsui test performed via an epidural catheter placed in the lumbar area is the unilateral motor response of the lower limbs. Studies show that longer pulse widths can stimulate peripheral nerves at a lower threshold current from a farther distance. Therefore, we designed a study to test the hypothesis that epidural catheter stimulation with a 1.0-msec pulse width would increase the incidence of bilateral motor response in parturients when compared with stimulation with a 0.1-msec pulse width.

Methods

Parturients requesting epidural analgesia were recruited into this randomized crossover study. The Tsui test was performed at both pulse widths before and five minutes after an epidural test dose of 2% lidocaine 3 mL. The primary outcome was the motor response pattern (either unilateral or bilateral) to the epidural catheter stimulation at baseline.

Results

Twenty women were recruited for the study, which was stopped early due to futility. The rates of unilateral motor response in the 0.1-msec (18/20) and the 1-msec (18/20) group were both 90% (rate difference, 0%; 95% confidence interval [CI], ?0.3 to 0.3; P = 1.0). The mean (SD) current required to elicit a motor response at baseline was 4.2 (2.6) mA in the 0.1-msec group and 1.7 (1.1) mA in the 1-msec group (mean difference, 2.5; 95% CI, 1.2 to 2.3; P < 0.001).

Conclusions

The motor response pattern following the stimulation of a lumbar epidural catheter with pulse widths of 0.1 msec or 1 msec is similar and typically unilateral. The threshold current is lower with the 1-msec pulse width stimulus.

Trial registration

www.clinicaltrials.gov, NCT02762149. Registered 2 May 2016.

     

Morphology and clinical importance of epidural membrane and periradicular fibrous tissue in lumbar spinal stenosis

Purpose

Compared to the ligamentum flavum (LF), morphology of the epidural membrane (EM) and the periradicular fibrous tissue (PRFT) has been largely ignored in studies of lumbar spinal stenosis (LSS). The aim of this prospective study was to elucidate the morphologies and clinical importance of the EM and PRFT in LSS.

Methods

Before starting this study, neural compressive EM (c-EM) and PRFT (c-PRFT) were defined as follows based on our microsurgical experience and a literature review. The c-EM is a constriction band or membrane obstructing dural tube expansion, and the c-PRFT is a fibrous tissue that compresses the nerve root and/or restricts its mobility. This study enrolled 134 patients who underwent microscopic decompression at L4/5. The morphologies of each patient’s EM and PRFT were observed and recorded. Specimens were obtained from randomly selected patients for histological evaluation.

Results

The EM and PRFT exhibited a wide morphological spectrum, from a fine strand to a substantial membrane. The c-EM alone was observed in four cases, the c-PRFT alone in 37 cases, and both in three cases. The c-PRFT was more frequently observed in patients with degenerative spondylolisthesis than in those without olisthesis (P < 0.05). Several cases exhibited interesting histological findings including many small arteries, chondrometaplasia, ganglion-like cyst formation, and hyalinized collagen fibers.

Conclusions

Some EM and PRFT transform into degenerative and substantial fibrous tissues during the process of symptomatic LSS development. Such morphological and histological changes can cause dural tear, symptomatic epidural hematoma, and/or inadequate decompression.

     

Assessing the real benefits of surgery for degenerative lumbar spinal stenosis without instability and spondylolisthesis: a single surgeon experience with a mean 8-year follow-up

Background

The degenerative lumbar spinal stenosis is one of the most commonly treated spinal disorders in older adults; despite its increasing frequency, it is not yet clear what the most effective therapy might be. The aim of this study is to investigate the very long term results of a homogenized cohort of patients suffering from lumbar spinal stenosis: the first subset of patients operated on with laminectomy and the second subset of patients was also advised to undergo laminectomy but never operated on.

Methods

Patients from both subgroups were advised to undergo surgery, according to the same criteria, in the period between 2000 and 2010 and were re-evaluated in the period between January and December 2016.

Results

Comparing the two subsets of patients, both suffering from clinically relevant LSS, the first subset returns a statistically significant clinical improvement at follow-up. The rate of excellent results decreases over years. Iatrogenic spinal instability incidence was found to be 3.8% in the present cohort.

Conclusions

Although the improvement of the first postoperative years decreases over time and despite the lack of general consensus, the lack of established shared guidelines and the limitations of this research, the results support the utilisation of surgery for the management of this condition.

Level of Evidence

3.

     

Outcome of surgery for degenerative lumbar scoliosis: an observational study using the Swedish Spine register

Purpose

The outcome of surgery for degenerative lumbar scoliosis was studied in the Swedish Spine register.

Methods

209 patients (mean age 66 years) were identified; 45 had undergone decompression and/or fusion of one segment (minor group) and 164 had undergone fusion of two or more segments, with or without decompression (major group).

Results

VAS back pain, VAS leg pain, ODI and EQ-5D index improved after surgery in both groups (p < 0.05), with medium to large effect sizes of surgery. Global assessment for back pain and satisfaction was significantly better in the major group than in the minor group (p < 0.05) at the 2-year follow-up. Additional spine surgery was observed in 57 out of the 209 patients during a mean period of 5.4 years.

Conclusion

Surgery for degenerative lumbar scoliosis improves quality of life with medium to large effect sizes, but carries a high risk of additional surgery.

     

Decompression plus fusion versus decompression alone for degenerative lumbar spondylolisthesis: a systematic review and meta-analysis

Purpose

To compare the clinical effectiveness of decompression plus fusion and decompression alone for patients with degenerative lumbar spondylolisthesis, a systematic review and meta-analysis of all available evidence was performed.

Methods

A search of the literature was conducted on PubMed/MEDLINE, EMBASE, and the Cochrane Collaboration Library. Relevant studies comparing decompression plus fusion and decompression alone were selected according to eligibility criteria. Predefined endpoints were extracted and meta-analyzed from the identified studies.

Results

Four randomized controlled trials and 13 observational studies were eligible. The pooled data revealed that fusion was associated with significantly higher rates of satisfaction and lower leg pain scores when compared with decompression alone. However, fusion significantly increased the intraoperative blood loss, operative time and hospital stay. Both techniques had similar ODI, back pain scores, complication rate, and reoperation rate.

Conclusions

Based on the available evidence, decompression plus fusion maybe be better than decompression alone in the treatment of degenerative spondylolisthesis. Fusion had advantages of improvement of clinical satisfaction, as well as reduction of postoperative leg pain, with similar complication rate to decompression alone.

     

Clinical outcomes of two minimally invasive transforaminal lumbar interbody fusion (TLIF) for lumbar degenerative diseases

Background

There are two modified TLIF, including MIS-TLIF and TLIF through Wiltse approach (W-TLIF). Although both of the two minimally invasive surgical procedures can be effective in the treatment for lumbar degenerative diseases, no comparative analysis has been made so far regarding their clinical outcomes.

Objective

To compare the clinical outcomes of MIS-TLIF and W-TLIF for the treatment for single-segment degenerative lumbar diseases.

Methods

Ninety-seven patients with single-segment degenerative lumbar disorders were included in this study. Forty-seven underwent MIS-TLIF surgery (group A). For group B, fifty patients underwent W-TLIF. The Japanese Orthopedic Association (JOA) score, the visual analog scale (VAS) of low back pain (LBP) and leg pain, MRI score and atrophy rate of CSA, interbody fusion rate were assessed during the postoperative follow-up.

Results

Incision length, blood loss, operative time, CPK, and postoperative incision pain VAS were better in group A (P < 0.05). The seconds of intraoperative fluoroscopy in groups A and B were 76 ± 9 and 7 ± 2, respectively (P < 0.05). In group B, The blood loss and CPK at L5-S1 were significantly higher than those at L4-5. Postoperative JOA scores, VAS of leg pain, and fusion rate were statistically the same between the two groups. VAS of LBP, MRI score, and atrophy rate of CSA was better in group A than in group B (P < 0.05).

Conclusion

Both methods are effective in the treatment for lumbar degenerative disease. MIS-TLIF has less blood loss, shorter surgical incision, and less lower postoperative back pain, while W-TLIF is less expensive for hospital stay with lower exposure to X-rays.

     

Adjacent segment pathology: natural history or effect of anterior cervical discectomy and fusion? A 10-year follow-up radiological multicenter study using an evaluation scale of the ageing spine

Purpose

Aim of this study is to compare late degenerative MRI changes in a subset of patients operated on with ACDF to a second subset of patients presenting indication to ACDF but never operated on.

Methods

Patients from both subgroups received surgical indication according to the same criteria. Both subgroups underwent a cervical spine MRI in 2004–2005 and 10 years later in 2015. These MRI scans were retrospectively evaluated with a cervical spine ageing scale.

Results

Comparing the two subset of patients both suffering from clinically relevant single-level disease returns no statistically significant difference in the degenerative condition of posterior ligaments, presence of degenerative spondylolisthesis, foraminal stenosis, diameter of the spinal canal, Modic alteration, and intervertebral discs degeneration at 10-year follow-up.

Conclusions

The adjacent segment degeneration represents, in the present cohort, a result of the natural history of cervical spondylosis rather than a consequence of fusion.

     

Adjacent intervertebral space infection after lumbar fusion

Background

Surgical site infection is a catastrophic complication after spinal surgery, which seriously affects the progress of rehabilitation and clinical outcome. Currently the clinical reports on spinal surgical site infections are mostly confined to the surgical segment itself and there are few reports on adjacent segment infections after spinal surgery.

Study design

Case report.

Objective

To report a clinical case with adjacent level infection after spinal fusion.

Methods

We report the case of a 68-year-old woman who underwent posterior lumbar 4?5 laminectomy, posterolateral fusion and internal fixation. The patient showed signs of surgical site infection, such as surgical site pain, high fever and increase of the inflammatory index 1 week after the operation. Magnetic resonance imaging (MRI) confirmed the diagnosis of adjacent intervertebral disc infection. The patient received early combined, high-dose anti-infection treatment instead of debridement.

Results

After the conservative treatment, the infection was controlled and the patient subsequently enjoyed a normal daily life.

Conclusion

Adjacent level infections can occur after spinal surgery. Early diagnosis and anti-infection treatment played an important role in the treatment of this kind of complication.

     

Use of colour Doppler and M-mode ultrasonography to confirm the location of an epidural catheter - a retrospective case series

Purpose

Epidural anesthesia and analgesia has a reported failure rate ranging from 13% to 32%. We describe a technique using colour Doppler and M-mode ultrasonography to determine the position of the epidural catheter after placement in adults.

Methods

This retrospective review included 37 adult patients who received postoperative epidural analgesia and underwent technically difficult epidural catheter placement. The demographic characteristics, type of surgery, use of ultrasonography, method of insertion, intervertebral level, and success of epidural localization using colour Doppler were noted for each patient. Pain scores on postoperative day 1 and the presence of a patchy block were also reviewed.

Results

Colour Doppler study helped to indicate the catheter’s path from the skin to the epidural space during saline injection in 33 patients (89%). Saline flow within the epidural space (catheter tip confirmation) was successfully detected with colour Doppler in 25 patients (67.5%) and with M-mode ultrasonography in 28 patients (75%). Appropriate dermatomal analgesia was noted in 35 patients (94.5%) during local anesthetic infusion.

Conclusion

Our preliminary data suggest the feasibility of using colour Doppler and M-mode ultrasonography to confirm proper epidural catheter placement.

     

Two occurrences of delayed epidural hematoma in different areas following decompressive craniectomy for acute subdural hematoma in a single patient: a case report

Background

Delayed epidural hematoma (DEH) following evacuation of traumatic acute subdural hematoma (ASDH) or acute epidural hematoma (EDH) is a rare but devastating complication, especially when it occurs sequentially in a single patient.

Case presentation

A 19-year-old man who developed contralateral DEH following craniotomy for evacuation of a traumatic right-side ASDH and then developed a left-side DEH of the posterior cranial fossa after craniotomy for evacuation of the contralateral DEH. He was immediately returned to the operating room for additional surgeries and his neurological outcome was satisfactory.

Conclusions

Although DEH occurring after evacuation of ASDH or acute EDH is a rare event, timely recognition is critical to prognosis.

     

Does elite swimming accelerate lumbar intervertebral disc degeneration and increase low back pain? A cross-sectional comparison

Purpose

The aim was to elucidate elite swimming’s possible influence on lumbar disc degeneration (DD) and low back pain (LBP).

Methods

Lumbar spine MRI was performed on a group of elite swimmers and compared to a matched Finnish population-based no-sport group.

Results

One hundred elite swimmers and 96 no-sport adults, mean age 18.7/20.8, respectively, participated. Overall, the two groups had similar prevalence of DD. Swimmers had more DD in the upper lumbar spine but tended to have less DD at the lowest level. Prevalence of bulges and disc herniations were similar, but swimmers had significantly more bulges at L4–5. The swimmers reported less LBP, although not significantly (N.S.). If degenerative findings were present, the association between them and LBP was stronger in the no-sport group.

Conclusion

Elite swimmers and controls had similar prevalence of DD and LBP, although the pattern of DD differed between the groups. In case of DD, swimmers reported less LBP, although N.S.

     

Endoscope-assisted oblique lumbar interbody fusion for the treatment of cauda equina syndrome: a technical note

Objective

The goal of this paper was to describe how endoscope-assisted oblique lumbar interbody fusion (OLIF) could remove huge lumbar disc herniation (HLDH) manifested with cauda equina syndrome (CES).

Methods

In this study, the authors made an attempt to treat CES with a direct endoscopic decompression through the OLIF corridor and performed OLIF in two patients with HLDH.

Results

Two patients with HLDH were successfully treated using OLIF with spinal endoscopic discectomy. We achieved direct ventral decompression by removal of herniated disc fragments located beyond the posterior longitudinal ligament (PLL). All preoperative symptoms in two patients improved postoperatively.

Conclusions

Endoscope-assisted oblique lumbar interbody fusion (OLIF) could successfully achieve neural decompression without additional posterior decompression in CES and could be used as an alternative treatment in well selected cases.

     

Sagittal balance parameters correlate with spinal conformational type and MRI changes in lumbar degenerative disc disease: results of a retrospective study

Purpose

Spinopelvic parameters can be useful in identifying risk factors for lumbar degenerative disc disease, but few studies assess patients with single-level disc herniation and most do not evaluate symptoms. This comparative retrospective study was aimed to analyse spinopelvic parameters, symptoms and MRI changes in patients with single-level lumbar disc herniation undergoing conservative or surgical treatment.

Methods

Patients with clinical and radiological assessment (Japanese Orthopaedic Association Score) and an MRI evaluation of the lumbar spine were identified and divided into two groups: surgically treated (group A) and not requiring surgery (group B). Spinopelvic parameters were determined on standing profile radiographs of the lumbar spine and pelvis, and mean values were compared to those reported in the literature for normal subjects. MRI findings were graded according to the system described by Pfirrmann et al.

Results

The study included 71 patients with single-level lumbar disc herniation: 26 in group A (39.4 ± 12.1 years) and 45 in group B (51.4 ± 17.2 years). The notable differences in spinopelvic parameter means between the two groups did not reach statistical significance. A positive correlations of age with pelvic tilt and Pfirrmann changes with pelvic incidence was only found in group A, while both groups showed highly significant positive correlations of pelvic incidence with the spine’s conformational type (p = 0.001).

Conclusions

Characteristic changes in spinopelvic parameters identified in patients with lumbar degenerative disc disease were a reduction in pelvic incidence, sacral slope and lumbar lordosis, with an increased pelvic tilt. These were found to correlate with MRI changes in surgically treated patients.

     

Epidural needle insertion

Background

Dural puncture, paraesthesia and vascular puncture are the most common complications of epidural catheter insertion. Their association with variation in midline needle insertion depth is unknown.

Objective

This study evaluated the risk of dural and vascular punctures and the unwanted events paraesthesia and multiple skin punctures related to midline needle insertion depth.

Material and methods

A total of 14,503 epidural catheter insertions including lumbar (L1–L5; n?=?5367), low thoracic (T7–T12, n?=?8234) and upper thoracic (T1–T6, n?=?902) insertions, were extracted from the German Network for Regional Anaesthesia registry between 2007 and 2015. The primary outcomes were compared with logistic regression and adjusted (adj) for confounders to determine the risk of complications/events. Results are presented as odds ratios (OR, [95% confidence interval]).

Main results

Midline insertion depth depended on body mass index, sex, and spinal level. After adjusting for confounders increased puncture depth (cm) remained an independent risk factor for vascular puncture (adjOR 1.27 [1.09–1.47], p?=?0.002) and multiple skin punctures (adjOR 1.25 [1.21–1.29], p?<?0.001). In contrast, dural punctures occurred at significantly shallower depths (adjOR 0.73 [0.60–0.89], p?=?0.002). Paraesthesia was unrelated to insertion depth. Body mass index and sex had no influence on paraesthesia, dural and vascular punctures. Thoracic epidural insertion was associated with a lower risk of vascular puncture than at lumbar sites (adjOR 0.39 [0.18–0.84], p?=?0.02).

Conclusion

Variation in midline insertion depth is an independent risk factor for epidural complications; however, variability precludes use of depth as a reliable guide to insertion in individual patients.

     

Responsiveness and minimum important change of the Oswestry Disability Index in Italian subjects with symptomatic lumbar spondylolisthesis

Background

This study aims to investigate the responsiveness and the minimum important change of the Italian version of the Oswestry Disability Index (ODI-I) in subjects with symptomatic specific low back pain associated with lumbar spondylolisthesis (SPL).

Materials and methods

One hundred and fifty-one patients with symptomatic SPL completed the ODI-I, a 0–100 numerical rating scale (NRS), and performed the prone and supine bridge tests. The global perception of effectiveness was measured with a 7-point Likert scale. Responsiveness was assessed by distribution methods (minimum detectable change [MDC], effect size [ES], standardized response mean [SRM]) and anchor-based methods (ROC curves).

Results

The MDC was 4.23, the ES was 0.95 and the SRM was 1.25. ROC analysis revealed an area under the curve of 0.76 indicating moderate discriminating capacity. The best cut-off point for the dichotomous outcome was 7.5 (sensitivity 90.3%, specificity 56.7%). .

Conclusions

The ODI-I proved to be responsive in detecting changes after conservative treatment in subjects with lumbar SPL.

Level of evidence

II.

     

Can facet joint fluid on MRI and dynamic instability be a predictor of improvement in back pain following lumbar fusion for degenerative spondylolisthesis?

Purpose

To investigate the relationship between lumbar facet fluid and dynamic instability in degenerative spondylolisthesis (DS), as well as the relationship between facet fluid and patient-reported outcomes following a posterior lumbar fusion.

Methods

We analyzed consecutive patients with degenerative spondylolisthesis undergoing single level posterior lumbar fusion from December 2010 to January 2013 at a single academic institution. We investigated the relationship between fluid in the facet joint as measured on axial MRI and the presence of dynamic instability. We investigated the impact of facet fluid, Modic changes, and dynamic instability on patient-reported outcomes.

Results

There was a significant association between the amount of facet joint fluid and the presence of dynamic instability (p = 0.03); as facet fluid increases, the probability of dynamic instability also increases. For every 1 mm of facet fluid, there was a 41.6 % increase (95 % CI 1.8–97) in the odds of dynamic instability. A facet fluid amount less than 0.5 mm gave a 90 % probability that there was no dynamic instability. The presence of facet fluid and dynamic instability were associated with achieving minimal clinical important difference (MCID) in low back pain following lumbar fusion (p = 0.04 and 0.05, respectively).

Conclusion

Facet joint fluid is associated with the presence of dynamic instability in DS. The presence of facet fluid and dynamic instability may predict increased likelihood of achieving MCID for improvement in back pain following posterior lumbar fusion.