Dynamic stabilization versus fusion for treatment of degenerative spine conditions.

Study design Comparative effectiveness review.Study rationale Spinal fusion is believed to accelerate the degeneration of the vertebral segment above or below the fusion site, a condition called adjacent segment disease (ASD). The premise of dynamic stabilization is that motion preservation allows for less loading on the discs and facet joints at the adjacent, non-fused segments. In theory, this should decrease the rate of ASD. However, clinical evidence of this theoretical decrease in ASD is still lacking. We performed a systematic review to evaluate the evidence in the literature comparing dynamic stabilization with fusion.Clinical question In patients 18 years or older with degenerative disease of the cervical or lumbar spine, does dynamic stabilization lead to better outcomes and fewer complications, including ASD, than fusion in the short-term and the long-term?Methods A systematic search and review of the literature was undertaken to identify studies published through March 7, 2011. PubMed, Cochrane, and National Guideline Clearinghouse Databases as well as bibliographies of key articles were searched. Two individuals independently reviewed articles based on inclusion and exclusion criteria which were set a priori. Each article was evaluated using a predefined quality-rating scheme.Results No significant differences were identified between fusion and dynamic stabilization with regard to VAS, ODI, complications, and reoperations. There are no long-term data available to show whether dynamic stabilization decreases the rate of ASD.Conclusions There are no clinical data from comparative studies supporting the use of dynamic stabilization devices over standard fusion techniques

An Evaluation of The Host Response to An Interspinous Process Device Based on A Series of Spine Explants: Device for Intervertebral Assisted Motion (DIAM®)

Background: The objective of this study was to evaluate the host response to an interspinous process device [Device for Intervertebral Assisted Motion (DIAM®)] based on a series of nine spine explants with a mean post-operative explant time of 35 months. Methods: Explanted periprosthetic tissues were processed for histology and stained with H&E, Wright-Giemsa stain, and Oil Red O. Brightfield and polarized light microscopy were used to evaluate the host response to the device and the resultant particulate debris. The host response was graded per ASTM F981-04. Quantitative histomorphometry was used to characterize particle size, shape, and area per ASTM F1877-05. The presence or absence of bone resorption was also evaluated when bony tissue samples were provided. Results: Periprosthetic tissues demonstrated a non-specific foreign body response composed of macrophages and foreign body giant cells to the DIAM® device in most of the accessions. The foreign body reaction was not the stated reason for explantation in any of the accessions. Per ASTM F981-04, a “very slight” to “mild” to “moderate” chronic inflammatory response was observed to the biomaterials and particulate, and this varied by tissue sample and accession. Particle sizes were consistent amongst the explant patients with mean particle size on the order of several microns. Osteolysis, signs of toxicity, necrosis, an immune response, and/or device related infection were not observed. Conclusions: Cyclic loading of the spine can cause wear in dynamic stabilization systems such as DIAM®. The fabric nature of the DIAM® device’s polyethylene terephthalate jacket coupled with the generation of polymeric particulate debris predisposes the device to a foreign body reaction consisting of macrophages and foreign body giant cells. Although not all patients are aware of symptoms associated with a foreign body reaction to a deeply implanted device, surgeons should be aware of the host response to this device

Traumatic Spondylopelvic Dissociation: A Report of Two Cases of Spondylolisthesis at L5-S1 and Review of Literature.

Study Design Retrospective chart review and review of literature. Objective Few case reports of traumatic L5-S1 displacement have been presented in the literature. Here we present two cases of traumatic spondylolisthesis showing both anterior and posterior displacement, the treatment algorithm, and a review of the literature. Methods The authors conducted a retrospective review of representative patients and a literature review of traumatic spondylolisthesis at the L5-S1 junction. Two representative patients were identified with traumatic spondylolisthesis: one with an anterior dissociation, and the other with a posterior dissociation. Results Radiographic, computed tomography, and magnetic resonance imaging illustrated the bony and soft tissue injury found in each patient, as well as the final stabilization and outcomes. Operative stabilization was necessary, and both patients were treated with open reduction internal fixation. The patient with posterior dissociation had complete recovery without neurologic sequelae. The patient with anterior dissociation had persistent bilateral L5-S1 radiculopathy with intact rectal tone, due to neurologic compression. Conclusions Few cases of traumatic spondylopelvic dissociation that are isolated to the L5-S1 disk space are described in the literature. We examined both an anterior and a posterior dissociation and treated both with L5-S1 posterior spinal fusion. The patient with anterior dissociation had persistent L5-S1 root injury; however, the patient with posterior dissociation had no neurologic deficits. This is the opposite of what is expected based on anatomy. These cases offer insight into the management of anterior and posterior L5-S1 spondylopelvic dissociation

Efficacy of interspinous device versus surgical decompression in the treatment of lumbar spinal stenosis: a modified network analysis.

Study designSystematic review using a modified network analysis.ObjectivesTo compare the effectiveness and morbidity of interspinous-device placement versus surgical decompression for the treatment of lumbar spinal stenosis.SummaryTraditionally, the most effective treatment for degenerative lumbar spinal stenosis is through surgical decompression. Recently, interspinous devices have been used in lieu of standard laminectomy.MethodsA review of the English-language literature was undertaken for articles published between 1970 and March 2010. Electronic databases and reference lists of key articles were searched to identify studies comparing surgical decompression with interspinous-device placement for the treatment of lumbar spinal stenosis. First, studies making the direct comparison (cohort or randomized trials) were searched. Second, randomized controlled trials (RCTs) comparing each treatment to conservative management were searched to allow for an indirect comparison through a modified network analysis approach. Comparison studies involving simultaneous decompression with placement of an interspinous device were not included. Studies that did not have a comparison group were not included since a treatment effect could not be calculated. Two independent reviewers assessed the strength of evidence using the GRADE criteria assessing quality, quantity, and consistency of results. The strengths of evidence for indirect comparisons were downgraded. Disagreements were resolved by consensus.ResultsWe identified five studies meeting our inclusion criteria. No RCTs or cohort studies were identified that made the direct comparison of interspinous-device placement with surgical decompression. For the indirect comparison, three RCTs compared surgical decompression to conservative management and two RCTs compared interspinous-device placement to conservative management. There was low evidence supporting greater treatment effects for interspinous-device placement compared to decompression for disability and pain outcomes at 12 months. There was low evidence demonstrating little to no difference in treatment effects between the groups for walking distance and complication rates.ConclusionThe indirect treatment effect for disability and pain favors the interspinous device compared to decompression. The low evidence suggests that any further research is very likely to have an important impact on the confidence in the estimate of effect and is likely to change the estimate. No significant treatment effect differences were observed for postoperative walking distance improvement or complication rates; however, findings should be considered with caution because of indirect comparisons and short follow-up periods

Lumbar ganglion cyst: Nosology, surgical management and proposal of a new classification based on 34 personal cases and literature review

AIM To analyze different terms used in literature to identify lumbar extradural cysts and propose a common scientific terminology; to elaborate a new morphological classification of this pathology, useful for clinical and surgical purposes; and to describe the best surgical approach to remove these cysts, in order to avoid iatrogenic instability or treat the pre-existing one. METHODS We retrospectively reviewed 34 patients with symptomatic lumbar ganglion cysts treated with spinal canal decompression with or without spinal fixation. Microsurgical approach was the main procedure and spinal instrumentation was required only in case of evident preoperative segmental instability. RESULTS The complete cystectomy with histological examination was performed in all cases. All patients presented an improvement of clinical conditions, evaluated by Visual Analogic Scale and Japanese Orthopaedic Association scoring. CONCLUSION Spinal ganglion cysts are generally found in the lumbar spine. The treatment of choice is the microsurgical cystectomy, which generally does not require stabilization. The need for fusion must be carefully evaluated: Preoperative spondylolisthesis or a wide joint resection, during the operation, are the main indications for spinal instrumentation. We propose the terms "ganglion cyst" to finally identify this spinal pathology and for the first time its morphological classification, clinically useful for all specialists

Effectiveness of Surgery for Lumbar Spinal Stenosis : A Systematic Review and Meta-Analysis

Peer reviewedPublisher PD

Lumbar interspinous process fixation and fusion with stand-alone interlaminar lumbar instrumented fusion implant in patients with degenerative spondylolisthesis undergoing decompression for spinal stenosis

Abstract STUDY DESIGN: Prospective cohort study. PURPOSE: To assess the ability of a stand-alone lumbar interspinous implant (interspinous/interlaminar lumbar instrumented fusion, ILIF) associated with bone grafting to promote posterior spine fusion in degenerative spondylolisthesis (DS) with vertebral instability. OVERVIEW OF LITERATURE: A few studies, using bilateral laminotomy (BL) or bilateral decompression by unilateral laminotomy (BDUL), found satisfactory results in stenotic patients with decompression alone, but others reported increased olisthesis, or subsequent need for fusion in DS with or without dynamic instability. METHODS: Twenty-five patients with Grade I DS, leg pain and chronic low back pain underwent BL or BDUL and ILIF implant. Olisthesis was 13% to 21%. Follow-up evaluations were performed at 4 to 12 months up to 25 to 44 months (mean, 34.4). Outcome measures were numerical rating scale (NRS) for back and leg pain, Oswestry disability index (ODI) and short-form 36 health survey (SF-36) of body pain and function. RESULTS: Fusion occurred in 21 patients (84%). None had increased olisthesis or instability postoperatively. Four types of fusion were identified. In Type I, the posterior part of the spinous processes were fused. In Type II, fusion extended to the base of the processes. In Type III, bone was present also around the polyetheretherketone plate of ILIF. In Type IV, even the facet joints were fused. The mean NRS score for back and leg pain decreased by 64% and 80%, respectively. The mean ODI score was decreased by 52%. SF-36 bodily pain and physical function mean scores increased by 53% and 58%, respectively. Computed tomography revealed failed fusion in four patients, all of whom still had vertebral instability postoperatively. CONCLUSIONS: Stand-alone ILIF with interspinous bone grafting promotes vertebral fusion in most patients with lumbar stenosis and unstable Grade I DS undergoing BL or BDUL

Comparison of Surgical Outcomes of the Posterior and Combined Approaches for Repair of Cervical Fractures in Ankylosing Spondylitis.

STUDY DESIGN: Retrospective cohort study. PURPOSE: To evaluate surgical outcomes and complications of cervical spine fractures in ankylosing spondylitis (CAS) patients who were treated using either the posterior (P) or combined approach (C). OVERVIEW OF LITERATURE: Ankylosing spondylitis typically causes progressive spinal stiffness that makes patients susceptible to spinal fractures. CAS is a highly unstable condition. There is contradictory evidence regarding which treatment option, the posterior or the combined approach, yields superior clinical results. METHODS: A single institution database was reviewed for data in the period 1999 to 2015. All CAS patients who underwent posterior or combined instrumented fusion were enrolled. We analyzed demographic data, radiographic results, perioperative complications, and postoperative results. RESULTS: Thirty-three patients were enrolled (23 in the P group, 10 in the C group). All patients presented with neck pain after a fall. In the P group, mean operative time was 161.1 minutes (100-327 minutes), and mean estimated blood loss (EBL) was 306.4 mL (50-750 mL). In the C group, 90% of patients underwent a staged procedure, typically with posterior surgery first. Mean EBL was 124 mL (25-337 mL). For posterior surgery, mean EBL was 458.3 mL (400-550 mL). EBL of posterior surgery in the C group was higher but this difference was not significant (p=0.16). Postoperative complication rate was higher in the C group but this difference was not significant (50% vs. 17.4%, p=0.09). In the follow-up period, no late reoperations were performed. Patients who underwent C surgery had a higher rate of neurological improvement but this difference was not significant (p=0.57). CONCLUSIONS: Both P and C provided good clinical results. P surgery had lower EBL, lower postoperative complication rate, and shorter length of stay than C surgery; none of these differences were statistically significant

Change of sagittal spinal alignment and its association with pain and function after lumbar surgery augmented with an interspinous implant

Background: Interspinous spacer/implants like the Device for Intervertebral Assisted Motion (DIAM™) are controversially yet commonly used in the surgical treatment of lumbar degenerative pathologies. Criticism is based on ill-defined indications, lack of superiority over decompression, and a poorly understood mechanical effect. Yet, continued use by surgeons implies their perceived clinical merit. We examined radiographic spinal alignment for 12 months, and pain and function for 24 months, after DIAM-augmented surgery to improve the understanding of the mechanical effect relating to clinical outcomes in patients. Methods: We undertook a single-surgeon prospective, longitudinal study of 40 patients (20 F, 20 M) who received DIAM-augmented surgery in treatment of their symptomatic lumbar degenerative condition. Outcomes measured included sagittal spinal alignment (lumbar lordosis, sacral inclination, primary (PDA), supradjacent (SDA) disc angles, and regional sagittal balance (RSB; standing lateral radiographs), and back and leg pain (visual analogue scale; VAS) and function (Oswestry Disability Index; ODI). Responders were identified as those with clinically meaningful improvement to pain (>20%) and function (>15%) at 24 months postoperatively; features of sagittal spinal alignment between responders and non-responders were examined. Results: Sagittal alignment was unchanged at 12 months. At 6 weeks postoperatively, PDA (mean (SD)) reduced by 2.2° (4.0°; p < 0.01) and more-so in back pain non-responders (3.8° (3.2°)) than responders (0.7° (4.4°); p < 0.05). Positive preoperative RSB in responders (26.7Rmm (42.3Rmm); Rmm is a system-relative measure) decreased at 6 weeks (by 3.1Rmm (9.1Rmm)). Non-responders had a negative RSB preoperatively (−1.0Rmm (32.0Rmm)) and increased at 6 weeks (11.2Rmm (15.5Rmm); p < 0.05). Clinically meaningful improvement for the whole cohort for back pain and function were observed to 24 months (back pain: 25.0% (28.0); function: 15.4% (17.6); both p < 0.0001). Conclusions: Unaltered sagittal alignment at 12 months was not related to symptoms after DIAM-augmented lumbar surgery. Subtle early flattening at the index disc angle was not maintained. Preoperative and early post-operative sagittal alignment may indicate response after DIAM-augmented surgery for mixed lumbar pathologies. Further investigation toward defining indications and patient suitability is warranted

Effectiveness of surgery for lumbar spinal stenosis

Background: The management of spinal stenosis by surgery has increased rapidly in the past two decades, however, there is still controversy regarding the efficacy of surgery for this condition. Our aim was to investigate the efficacy and comparative effectiveness of surgery in the management of patients with lumbar spinal stenosis. Methods: Electronic searches were performed on MEDLINE, EMBASE, AMED, CINAHL, Web of Science, LILACS and Cochrane Library from inception to November 2014. Hand searches were conducted on included articles and relevant reviews. We included randomised controlled trials evaluating surgery compared to no treatment, placebo/sham, or to another surgical technique in patients with lumbar spinal stenosis. Primary outcome measures were pain, disability, recovery and quality of life. The PEDro scale was used for risk of bias assessment. Data were pooled with a random-effects model, and the GRADE approach was used to summarise conclusions. Results: Nineteen published reports (17 trials) were included. No trials were identified comparing surgery to no treatment or placebo/sham. Pooling revealed that decompression plus fusion is not superior to decompression alone for pain (mean difference -3.7, 95% confidence interval -15.6 to 8.1), disability (mean difference 9.8, 95% confidence interval -9.4 to 28.9), or walking ability (risk ratio 0.9, 95% confidence interval 0.4 to 1.9). Interspinous process spacer devices are slightly more effective than decompression plus fusion for disability (mean difference 5.7, 95% confidence interval 1.3 to 10.0), but they resulted in significantly higher reoperation rates when compared to decompression alone (28% v 7%, P < 0.001). There are no differences in the effectiveness between other surgical techniques for our main outcomes. Conclusions: The relative efficacy of various surgical options for treatment of spinal stenosis remains uncertain. Decompression plus fusion is not more effective than decompression alone. Interspinous process spacer devices result in higher reoperation rates than bony decompression