Interspinous Process Decompression Research Articles

ID: 212778 Minimally Invasive Interspinous Process Decompression for Elderly Patient With L1-L2 Lumbar Stenosis

Lumbar spinal stenosis (LSS) is the progressive narrowing of the spinal canal. In the USA, the prevalence of LSS in those older than 60 is 47% making it one of the most common causes of lower back pain (1). Diagnosis is multifaceted and based on history, physical exam, and imaging studies. LSS with neurogenic claudication characteristically presents as pain relieved by sitting and worse with standing (2). The initial management of LSS consists of physiotherapy and anti-inflammatory medications followed by epidural steroid injections. When conservative treatment fails, the most common surgical management is decompressive laminectomy with or without fusion (3). Open spinal surgery, however, is not without risks given that the majority of LSS patients are elderly and have multiple comorbidities. An effective procedure in relieving symptomatic LSS is minimally invasive interspinous process decompression which entails an interspinous spacer that is implanted under local anesthesia (4).

Improvement in Neurogenic Pain with Epidural Injections Following Interspinous Spacer Implantation in Patients with Lumbar Stenosis: A Case Series

Background: Lumbar spinal stenosis with neurogenic claudication can be a debilitating condition, affecting quality of life. Interspinous spacer implantation is a minimally invasive procedure for treatment of lumbar spinal stenosis with neurogenic claudication and associated symptoms by minimizing spinal extension and therefore neural compression. Case Presentation: This case series presents 4 cases of patients with multilevel stenosis, most radiographically severe in the lumbar region, all who received interspinous spacers at L3-4 and L4-5 after minimal improvement in symptoms with conservative management including epidural injections. In all 4 cases, patients reported improved standing and gait but limited improvement in pain and overall function after interspinous spacer implantation. Each patient underwent repeat epidural injections at or below the level of the interspinous spacer with significant improvement in pain for up to 6 months. Conclusion: Our conclusion is that either postspacer epidural injections helped reduce inflammation associated with the implantation procedure, or the spacer maintained an open space to allow the injectate to permeate areas with the most stenosis and help reduce inflammation and therefore pain. Key words: Epidural injection, interspinous process decompression, interspinous spacer, interspinous spacer implant, low back pain, lumbar spinal stenosis, neurogenic claudication, spinal stenosis

Cost-effectiveness and Safety of Interspinous Process Decompression (Superion).

ObjectiveThere are several treatment options for patients suffering from lumbar spinal stenosis, including surgical and conservative care. Interspinous spacer decompression using the Superion device offers a less invasive procedure for patients who fail conservative treatment before traditional decompression surgery. This review assesses the current cost-effectiveness, safety, and performance of lumbar spinal stenosis treatment modalities compared with the Superion interspinous spacer procedure.MethodsEMBASE and PubMed were searched to find studies reporting on the cost-effectiveness, safety, and performance of conservative treatment, including medicinal treatments, epidural injections, physical therapy, and alternative methods, as well as surgical treatment, including laminectomy, laminectomy with fusion, and interspinous spacer decompression. Results were supplemented with manual searches.ResultsDespite substantial costs, persistent conservative treatment (>12 weeks) of lumbar spinal stenosis showed only minimal improvement in pain and functionality. When conservative treatment fails, surgery is more effective than continuing conservative treatment. Lumbar laminectomy with fusion has considerably greater cost than laminectomy alone, as the length of hospital stay increases, the costs for implants are substantial, and complications increase. Although laminectomy and the Superion have comparable outcomes, the Superion implant is positioned percutaneously. This approach may minimize the direct and indirect costs of outpatient rehabilitation and absenteeism, respectively.ConclusionsSuperion interspinous lumbar decompression is a minimally invasive procedure for patients with lumbar spinal stenosis who have failed conservative treatment. Compared with extending conservative treatment or traditional spinal surgery, interspinous lumbar decompression reduces the direct and indirect costs associated with lumbar spinal stenosis.

A Review of Emerging Evidence for Utilization of a Percutaneous Interspinous Process Decompression Device to Treat Symptomatic Lumbar Adjacent-Segment Degeneration.

ObjectivePostlaminectomy syndrome diagnoses secondary to adjacent segment degeneration are a substantial and rising cause of morbidity in the United States. Emerging spinal cord neuromodulation technologies have produced successful outcomes for postlaminectomy neuropathic pain but are less effective in treating neurogenic claudication secondary to recurrent lumbar stenosis. Percutaneous interspinous process decompression systems can be used as a salvage treatment modality for persistent structural neurogenic claudication in postlaminectomy syndrome or after spinal cord stimulator implantation.MethodsThis paper is a review of emerging evidence for efficacious utilization of percutaneous interspinous process decompression.ResultsA recent pragmatic trial of subjects who underwent percutaneous interspinous process decompression for lumbar stenosis with intermittent neurogenic claudication reported that 63% (26/41) maintained minimal clinically important improvement in visual analog scale (VAS) leg pain, 61% (25/41) in VAS back pain, 78% (32/41) in function objective values, and 88% (36/41) reported satisfaction with treatment at 12 months postop. All subjects in a small case series of seven individuals with postlaminectomy adjacent-segment disease reported postoperative satisfaction scores of 3 or 4 on a 0–4 scale and were also able to decrease or wean completely off controlled pain medications. In another study, there was a significant decrease in average leg pain (60% improvement, P < 0.0001, N = 25) and axial low back pain (58% improvement, P < 0.0001, N = 25) in patients who underwent one- or two-level percutaneous interspinous process decompression as a rescue treatment for reemerging neurogenic claudication after spinal cord stimulator implantation.ConclusionsThe spine often is a focus of progressive disease. Furthermore, mechanical changes associated with spinal instrumentation can lead to additional disease at adjacent levels. Many individuals will present with symptomatic neurogenic claudication recalcitrant to multimodal management strategies, including even the most sophisticated neuromodulation technologies. Implementation of salvage percutaneous interspinus process decompression implantation in cases of adjacent segment degeneration or incomplete spinal cord stimulation can decompress structural causes of neurogenic claudication while sparing the patient from more invasive surgical reoperation techniques.

Interspinous Process Decompression With The Superion® Spacer For Lumbar Spinal Stenosis: Real-World Experience From A Device Registry.

BackgroundInterspinous process decompression (IPD) with stand-alone spacers has demonstrated excellent long-term clinical benefit for patients with lumbar spinal stenosis (LSS).MethodsIPD used the Superion® Indirect Decompression System (Vertiflex, Carlsbad, CA, USA). Perioperative and clinical data were captured via a registry for patients treated with IPD for LSS with intermittent neurogenic claudication. Three-hundred sixteen physicians at 86 clinical sites in the US participated. Patient data were captured from in-person interviews and a phone survey. Outcomes included intraoperative blood loss, procedural time, leg and back pain severity (100 mm VAS), patient satisfaction and treatment approval at 3 weeks, 6 and 12 months.ResultsThe mean age of registry patients was 73.0 ± 9.1 years of which 54% were female. Mean leg pain severity decreased from 76.6 ± 22.4 mm preoperatively to 30.4 ± 34.6 mm at 12 months, reflecting an overall 60% improvement. Corresponding responder rates were 64% (484 of 751), 72% (1,097 of 1,523) and 75% (317 of 423) at 3 weeks, 6 and 12 months, respectively. Back pain severity improved from 76.8 ± 22.2 mm preoperatively to 39.9 ± 32.3 mm at 12 months (48% improvement); 12-month responder rate of 67% (297 of 441). For patient satisfaction at 3 weeks, 6 and 12 months, 89%, 80%, and 80% were satisfied or somewhat satisfied with their treatment and 90%, 75%, and 75% would definitely or probably undergo the same treatment again. In the phone survey, the rate of revision was 3.6% (51 of 1,426).ConclusionThese registry findings support the clinical adoption of minimally invasive IPD in patients with neurogenic claudication associated with LSS.

155. Interspinous process decompression with the Superion® Spacer for lumbar spinal stenosis: real world experience from a device registry

BACKGROUND CONTEXT Interspinous process decompression (IPD) with stand-alone spacers has demonstrated excellent long-term clinical benefit for patients with lumbar spinal stenosis (LSS). PURPOSE Real-world experience with interspinous process decompression. The primary aim of the registry is to prospectively collect a set of perioperative and clinical outcomes among patients treated with stand-alone IPD for symptomatic LSS. STUDY DESIGN/SETTING Stand-alone IPD using the Superion Indirect Decompression System (Vertiflex, Carlsbad, CA USA). Perioperative and clinical data were captured via a registry for patients treated with IPD for LSS with intermittent neurogenic claudication. Seventy-five physicians at 53 clinical sites in the US participated. Outcomes included intraoperative blood loss, procedural time, leg and back pain severity, self-defined functional objective, and patient satisfaction at 3 weeks, 6 and 12 months. PATIENT SAMPLE To date, 722 patients have undergone IPD and enrolled in the PRESS registry with a mean age of 73.0 ± 10.7 years including 379 females (53%). The maximum number of patients providing pain severity data was 603, 521, 184 and 53 at baseline, 3 weeks, 6 and 12 months, respectively. OUTCOME MEASURES Patient-reported outcomes included leg and back pain severity by 100 mm Visual Analog Scale prior to IPD as well as at 3 weeks, 6 and 12 months, postoperatively. At each follow-up interval, patients were also asked to indicate the extent to which they had achieved their Self-Defined Functional Objective, on a 1 to 5 scale, with 1 indicating no progress at all, and 5 indicating complete achievement. Additionally, patient satisfaction with IPD was queried as satisfied, somewhat satisfied, somewhat dissatisfied, or dissatisfied. Treatment approval with IPD was characterized as definitely yes, probably yes, probably not or definitely not with respect to whether the patient would repeat the treatment. METHODS Perioperative and clinical data were captured via a registry for patients treated with IPD for LSS with intermittent neurogenic claudication. RESULTS To date, 722 patients have undergone IPD and enrolled in this registry with a mean age of 73.0 ± 10.7 years including 379 females (53%). Average intraoperative blood loss was 6.1 ± 7.7 mL; median operative duration was 39.0 minutes (range: 7.0 to 210.0 mins). Mean leg pain severity decreased from 67.3 ± 26.5 mm preoperatively to 28.7 ± 33.0 mm at 12 months, reflecting an overall 57% improvement. Corresponding responder rates were 64% (335 of 521), 61% (113 of 184) and 66% (35 of 53) at 3 weeks, 6 and 12 months, respectively. Back pain severity improved similarly from 67.9 ± 25.9 mm preoperatively to 28.6 ± 31.3 mm at 12 months (58% improvement); 12-month responder rate of 64% (34 of 53). Functional objective responder rates were 63%, 67% and 81% at 3 weeks, 6 and 12 months, respectively. For patient satisfaction at 3 weeks, 6 and 12 months, 89%, 84%, and 91% were satisfied or somewhat satisfied with their treatment and 91%, 80%, and 87% would definitely or probably undergo the same treatment again. In a phone survey, the rate of revision or reoperation was 4% (21 of 517). CONCLUSIONS These registry findings support the clinical adoption of IPD in patients considering minimally-invasive options to manage chronically recalcitrant LSS symptoms. FDA DEVICE/DRUG STATUS Superion Indirect Decompression System (Approved for this indication).

Toward a cure for lumbar spinal stenosis: The potential of interspinous process decompression

There is a growing impetus to treat aging as a disease in the quest to significantly extend the human life span through cellular regeneration methods. This approach, while promising, overlooks the fact that the evolutionary adaptation to bipedalism puts the human body in a distinctively vulnerable biomechanical and functional position. Orthograde human posture places unusually-high axial compressive loads on the weight-bearing joints of the skeleton, resulting in arthritic deterioration with aging. The effects are particularly robust in the lumbar spine were age-related degeneration, most commonly lumbar spinal stenosis (LSS), is ubiquitous among the elderly. It is postulated that re-establishing a favorable mechanical environment via interventions that unload the affected spinal joint complex may mitigate and potentially reverse the structural damage that is the cardinal pathoanatomical feature of this disease. The hypothesis of this paper is that a minimally-invasive surgical procedure, interspinous process decompression (IPD), which utilizes a stand-alone intervertebral spacer, effectively unloads the diseased spinal motion segment providing a healthy micro-environment to reverse and repair age-related and genetic deterioration of the spinal motion segment. Several lines of supporting evidence are provided from long-term follow-up results of a randomized controlled trial of IPD safety and effectiveness of the Superion® device including clinical outcomes, reoperation rates, opioid analgesic usage and advanced imaging utilization. All of these outcomes show uniquely-favorable trends with time that imply that the benefits of IPD are structural. The compendium of evidence suggests that IPD offers both a durable palliative effect due to direct blocking of back extension and a disease-modifying effect due to unloading of the spinal joint complex.

Interspinous process decompression is associated with a reduction in opioid analgesia in patients with lumbar spinal stenosis.

BackgroundLumbar spinal stenosis (LSS) causes significant pain and functional impairment, and medical management has increasingly included the prescription of opioid-based analgesics. Interspinous process decompression (IPD) provides a minimally-invasive treatment option for LSS.MethodsThis study estimated the type, dosage, and duration of opioid medications through 5 years of follow-up after IPD with the Superion Indirect Decompression System (Vertiflex Inc., Carlsbad, CA USA). Data were obtained from the Superion-treatment arm of a randomized controlled noninferiority trial. The prevalence of subjects using opiates was determined at baseline through 60 months. Primary analysis included all 190 patients randomized to receive the Superion device. In a subgroup of 98 subjects, we determined opioid-medication prevalence among subjects with a history of opioid use.ResultsAt baseline, almost 50% (94 of 190) of subjects were using opioid medication. Thereafter, there was a sharp decrease in opioid-medication prevalence from 25.2% (41 of 163) at 12 months to 13.3% (20 of 150) at 24 months to 7.5% (8 of 107) at 60 months. Between baseline and 5 years, there was an 85% decrease in the proportion of subjects using opioids. A similar pattern was also observed among subjects with a history of opiates prior to entering the trial.ConclusionStand-alone IPD is associated with a marked decrease in the need for opioid medications to manage symptoms related to LSS. In light of the current opiate epidemic, such alternatives as IPD may provide effective pain relief in patients with LSS without the need for opioid therapy.

Interspinous Process Decompression Improves Quality of Life in Patients with Lumbar Spinal Stenosis.

Lumbar spinal stenosis has been shown to negatively impact health-related quality of life. Interspinous process decompression (IPD) is a minimally invasive procedure that utilizes a stand-alone spacer to serve as a joint extension blocker to relieve neural compression in patients with spinal stenosis. Using the 5-year results from an FDA randomized controlled trial of IPD, the quality of life in 189 patients treated with the Superion® spacer was evaluated with the SF-12. Physical and mental component summary (PCS, MCS) scores were computed preoperatively and at annual intervals. For the PCS, mean scores improved from 29.4 ± 8.1 preoperatively to 41.2 ± 12.4 at 2 years (40%) and to 43.8 ± 11.6 at 5 years (49%) (p<0.001 for both comparisons). At 2 years, 81% (103 of 128) of subjects demonstrated maintenance or improvement in PCS scores. The mean MCS score improved from 50.0 ± 12.7 preoperatively to 54.4 ± 10.6 and 54.7 ± 8.6 at 2 and 5 years, respectively (p>0.10 for both comparisons). These results demonstrate that the significant impairment in physical well-being found in patients with lumbar spinal stenosis can be ameliorated, in large part, by IPD treatment.

Long-term results with percutaneous interspinous process devices in the treatment of neurogenic intermittent claudication.

Neurogenic intermittent claudication (NIC) is the main symptom of degenerative lumbar spinal stenosis. Percutaneous interspinous process decompression devices (IPDs) have been designed as an alternative therapy to conservative treatment and to open decompressive surgery for patients suffering from NIC. Initial short-term results were encouraging. We present the long-term results of a group of patients that we followed to provide insight on long-term outcomes and effectiveness of this technique compared to other decompression methods. Fifteen patients operated for NIC by implantation of percutaneous IPDs have been prospectively monitored for reoperations or complications. Follow-up (FU) was interrupted if the patient was reoperated. Results were considered poor if the patient had to be reoperated at any stage of the FU or if the treatment failed to alleviate the pain after 6 months. Results were considered average if the patient still suffered some pain but did not require reoperation. The patients were followed up to 7 years after the initial surgery. The mean length of the FU was 3.53 years and all patients could be followed. At the end of the FU, the results were good in only 20.0% (3/15), average in 13.3% (2/15) and poor in 66.7% (10/15). Despite initial satisfactory results, long-term FU is disappointing, with 80% poor or average results. The long-term reoperation rate is high (66.6%), increases over time and is higher than after implantation of IPDs for decompression augmentation. Although this technique is simple and safe, its effectiveness seems short-lived. We recommend cautious use and informing patients about the risk of relatively early failure and recurrence.

Five-year durability of stand-alone interspinous process decompression for lumbar spinal stenosis.

BackgroundLumbar spinal stenosis is the most common indication for spine surgery in older adults. Interspinous process decompression (IPD) using a stand-alone spacer that functions as an extension blocker offers a minimally invasive treatment option for intermittent neurogenic claudication associated with spinal stenosis.MethodsThis study evaluated the 5-year clinical outcomes for IPD (Superion®) from a randomized controlled US Food and Drug Administration (FDA) noninferiority trial. Outcomes included Zurich Claudication Questionnaire (ZCQ) symptom severity (ss), physical function (pf), and patient satisfaction (ps) subdomains, leg and back pain visual analog scale (VAS), and Oswestry Disability Index (ODI).ResultsAt 5 years, 84% of patients (74 of 88) demonstrated clinical success on at least two of three ZCQ domains. Individual ZCQ domain success rates were 75% (66 of 88), 81% (71 of 88), and 90% (79 of 88) for ZCQss, ZCQpf, and ZCQps, respectively. Leg and back pain success rates were 80% (68 of 85) and 65% (55 of 85), respectively, and the success rate for ODI was 65% (57 of 88). Percentage improvements over baseline were 42%, 39%, 75%, 66%, and 58% for ZCQss, ZCQpf, leg and back pain VAS, and ODI, respectively (all P<0.001). Within-group effect sizes were classified as very large for four of five clinical outcomes (ie, >1.0; all P<0.0001). Seventy-five percent of IPD patients were free from reoperation, revision, or supplemental fixation at their index level at 5 years.ConclusionAfter 5 years of follow-up, IPD with a stand-alone spacer provides sustained clinical benefit.

Superion Interspinous Spacer Treatment of Moderate Spinal Stenosis: 4-Year Results.

To determine 4-year clinical outcomes in patients with moderate lumbar spinal stenosis treated with minimally invasive stand-alone interspinous process decompression using the Superion device. The 4-year Superion data were extracted from a randomized, controlled Food and Drug Administration investigational device exemption trial. Patients with intermittent neurogenic claudication relieved with back flexion who failed at least 6 months of nonsurgical management were enrolled. Outcomes included Zurich Claudication Questionnaire (ZCQ) symptom severity (ss), physical function (pf) and patient satisfaction (ps) subdomains, leg and back pain visual analog scale (VAS), and Oswestry Disability Index (ODI). At 4-year follow-up, 89 of the 122 patients (73%) provided complete clinical outcome evaluations. At 4 years after index procedure, 75 of 89 patients with Superion (84.3%) demonstrated clinical success on at least 2 of 3 ZCQ domains. Individual component responder rates were 83% (74/89), 79% (70/89), and 87% (77/89) for ZCQss, ZCQpf, and ZCQps; 78% (67/86) and 66% (57/86) for leg and back pain VAS; and 62% (55/89) for ODI. Patients with Superion also demonstrated percentage improvements over baseline of 41%, 40%, 73%, 69%, and 61% for ZCQss, ZCQpf, leg pain VAS, back pain VAS, and ODI. Within-group effect sizes all were classified as very large (>1.0): 1.49, 1.65, 1.42, 1.12, and 1.46 for ZCQss, ZCQpf, leg pain VAS, back pain VAS, and ODI. Minimally invasive implantation of the Superion device provides long-term, durable relief of symptoms of intermittent neurogenic claudication for patients with moderate lumbar spinal stenosis.

Baastrup Disease/Interspinous Bursitis

Baastrup disease (BD), an uncommon back pain syndrome, is characterized by pathologic approximation of adjacent spinous processes on a sagittal plane image. BD occurs most commonly at the lumbar L4-L5 level and tends to be more common in the elderly. The etiology is not precisely known, but BD may develop secondary to chronic active inflammatory facet arthropathy, leading to interspinous osteophytes and approximation of the adjacent spinous processes. Clinically, BD should be considered in the differential diagnosis of back pain if there is (1) midline back pain reproduced with palpation of the spinous process and exacerbated by extension of the lumbar spine and (2) direct contact of adjacent spinous processes on the lateral view of a plain x-ray image. Magnetic resonance imaging is more sensitive in detecting interspinous inflammation and the formation of bursa and new bone. Major differential diagnoses of BD include proliferative hyperostosis of the lumbar spinous processes, degenerative disease of the spine, sclerotic bone metastases to the spine, and ankylosing spondylosis. BD can be managed initially with nonsteroidal antiinflammatory drugs, a short-term steroid dose pack, and physical therapy. Injection of a local anesthetic to the inflamed spinous process and associated interspinous ligaments may be diagnostic, and injection of a local anesthetic/corticosteroid combination may be therapeutic. Surgery is reserved for patients with refractory BD. Surgical options include interspinous process decompression devices and excision of the affected spinous processes.

164 Failure Rates and Complications of Interspinous Process Decompression Devices

INTRODUCTION:Spacers placed between the lumbar spinous processes represent a promising surgical treatment alternative for a variety of spinal pathologies. They provide an unloading distractive force to the stenotic motion segment, restoring foraminal height, and have the potential to relieve symptom

Interspinous Process Decompression: Expanding Treatment Options for Lumbar Spinal Stenosis.

Interspinous process decompression is a minimally invasive implantation procedure employing a stand-alone interspinous spacer that functions as an extension blocker to prevent compression of neural elements without direct surgical removal of tissue adjacent to the nerves. The Superion® spacer is the only FDA approved stand-alone device available in the US. It is also the only spacer approved by the CMS to be implanted in an ambulatory surgery center. We computed the within-group effect sizes from the Superion IDE trial and compared them to results extrapolated from two randomized trials of decompressive laminectomy. For the ODI, effect sizes were all very large (>1.0) for Superion and laminectomy at 2, 3, and 4 years. For ZCQ, the 2-year Superion symptom severity (1.26) and physical function (1.29) domains were very large; laminectomy effect sizes were very large (1.07) for symptom severity and large for physical function (0.80). Current projections indicate a marked increase in the number of patients with spinal stenosis. Consequently, there remains a keen interest in minimally invasive treatment options that delay or obviate the need for invasive surgical procedures, such as decompressive laminectomy or fusion. Stand-alone interspinous spacers may fill a currently unmet treatment gap in the continuum of care and help to reduce the burden of this chronic degenerative condition on the health care system.

Failure rates and complications of interspinous process decompression devices: a European multicenter study.

OBJECT Spacers placed between the lumbar spinous processes represent a promising surgical treatment alternative for a variety of spinal pathologies. They provide an unloading distractive force to the stenotic motion segment, restoring foraminal height, and have the potential to relieve symptoms of degenerative disc disease. The authors performed a retrospective, multicenter nonrandomized study consisting of 1108 patients to evaluate implant survival and failure modes after the implantation of 8 different interspinous process devices (IPDs). METHODS The medical records of patients who had undergone placement of an IPD were retrospectively evaluated, and demographic information, diagnosis, and preoperative pain levels were recorded. Preoperative and postoperative clinical assessments in the patients were based on the visual analog scale. A minimum of 3 years after IPD placement, information on long-term outcomes was obtained from additional follow-up or from patient medical and radiological records. RESULTS One thousand one hundred eight patients affected by symptomatic 1- or 2-level segmental lumbar spine degenerative disease underwent placement of an IPD. The complication rate was 7.8%. There were 27 fractures of the spinous process and 23 dura mater tears with CSF leakage. The ultimate failure rate requiring additional surgery was 9.6%. The reasons for revision, which always involved removal of the original implant, were acute worsening of low-back pain or lack of improvement (45 cases), recurrence of symptoms after an initial good outcome (42 cases), and implant dislocation (20 cases). CONCLUSIONS The IPD is not a substitute for a more invasive 3-column fusion procedure in cases of major instability and spondylolisthesis. Overdistraction, poor bone density, and poor patient selection may all be factors in the development of complications. Preoperatively, careful attention should be paid to bone density, appropriate implant size, and optimal patient selection.

Indications and contraindications: interspinous process decompression devices in lumbar spine surgery.

Interspinous process decompression devices (IPD) allow a minimally invasive treatment of lumbar spinal stenosis (LSS), but their use is discussed highly controversial. Several level I studies suggest that IPD implantation is a viable alternative for both conservative treatment and decompression, but clear indications and contraindications are still missing. This study was designed to explore the perspectives and limitations of IPDs and to evaluate the role of these devices in general. The study is based on a questionnaire sent to all hospitals registered in the German Hospital Address Register 2010 with an orthopedic, neurosurgerical, or spine surgery department (n = 1,321). The questionnaire was reviewed by experienced spine surgeons and statisticians, and included both single-response, close-ended, and multiple-response open-ended questions. We received 329 (24.9%) entirely analyzable questionnaires. A total of 164 respondents (49.8%) stated that IPDs are a treatment option for LSS, and 135 of the 164 respondents (82.3%) use them. Poor clinical experience (60%) and lack of evidence (53.9%) are the main reasons cited for not using IPDs. We detected a high negative correlation between the size of the hospital, the number of outpatients and inpatients treated for LSS and other spine pathologies, and the use of IPDs (p = 0.001). Most respondents prefer the combination of open decompression and IPD (64.4%; n = 87). A total of 9.6% (n = 13) of the users favor IPD implantation as a stand-alone procedure. Overall, 25.9% n = 35 use both options. Most surgeons aim to relieve the facet joints (87.7%) and to stabilize a preexisting instability (75.4%). They recommend IPDs in the segments L2-L3 (77%), L3-L4 (98.5%), and L4-l5 (99.3%) and consider that IPD implanation also could be done at the L5-S1 segment (40.1%). Overall, 64.4% (n = 87) of the users recommend limiting IPD implantation to two segments. Infection (96.3%), fracture (94.8%), isthmic spondylolisthesis (77%), degenerative spondylolisthesis (higher than Meyerding I [57%]), lumbar spine scoliosis (48.1%), and osteoporosis (50.4%) are seen as contraindications for IPD. No clear consensus exists among spine surgeons concerning the use of IPD for LSS treatment. The study showed that hospital-related parameters also influence decision making for or against the use of IPDs. However, despite the lack of evidence, the indications and contraindications which had been identified in the present study might contribute to improved outcomes after IPD implantation or at least prevent harm to patients.

Interspinous spacer decompression (X-STOP) for lumbar spinal stenosis and degenerative disk disease: A multicenter study with a minimum 3-year follow-up

Interspinous distraction devices provide an effective treatment for patients suffering from lumbar spinal stenosis and/or degenerative disk disease. The aim of this multicenter study was the prospective evaluation of patients treated for symptomatic lumbar spinal stenosis with interspinous process decompression (IPD) implants compared with a population of patients managed with conservative treatment.542 patients affected by symptomatic lumbar spine degenerative disease were enrolled in a controlled trial.422 patients underwent surgical treatment consisting of X-STOP device implantation, whereas 120 control cases were managed conservatively. Both patient groups underwent follow-up evaluations at 6, 12, 24, and 36 months using the Zurich Claudication Questionnaire, the Visual Analog Scale score and spinal lumbar X-rays, CT scans and MR imaging.One-year follow-up evaluation revealed positive good results in the 83.5% of patients treated with IPD with respect to 50% of the nonoperative group cases. During the first three years, in 38 out of the 120 control cases, a posterior decompression and/or spinal fixation was performed because of unsatisfactory results of the conservative therapy. In 24 of 422 patients, the IPD device had to be removed, and a decompression and/or pedicle screw fixation was performed because of the worsening of neurological symptoms.Our results support the effectiveness of surgery in patients with stenosis. IPD may offer an effective and less invasive alternative to classical microsurgical posterior decompression in selected patients with spinal stenosis and lumbar degenerative disk diseases.

Device-Related Complications of the Coflex Interspinous Process Implant for the Lumbar Spine

Introduction Coflex, a type of interspinous process implant, can provide intervertebral dynamic stability for surgical segments and relieve lumbocrural pain effectively. However, few studies have described the avoidance and therapeutic strategies of Coflex implant complications. Materials and Methods Coflex implant complications included intraoperative or postoperative spinous process fracture, aggravated postoperative lumbocrural pain, dislodgment, and malposition in this study. The complications were analyzed, and therapeutic strategies were applied according to the specific complication. The Visual Analogue Scale and Oswestry Disability Index scores were evaluated by using the paired-samples test of SPSS 12.0 Results Conservative treatment was provided to seven patients who experienced aggravated lumbocrural pain even though their devices remained in the correct position, and pedicle screw treatment was used as an alternative in four cases. The Visual Analogue Scale and Oswestry Disability Index scores showed evident improvement in these patients. The Visual Analogue Scale and Oswestry Disability Index scores of two patients who underwent revision also improved. Conclusion Coflex implants should be avoided in patients with osteoporosis, a narrow interspinous space and intervertebral coronal spondylolysis, or sagittal instability; furthermore, the device choice, depth of implantation, and clamping intensity should be appropriate. Conservative treatment can be provided to patients with symptoms if the device remains in the correct position; however, revisions and salvages should be undertaken with internal fixation of pedicle screws for patients with device malposition, intraoperative implantation failure, or device intolerance. Disclosure of Interest None declared References Richards JC, Majumdar S, Lindsey DP, Beaupré GS, Yerby SA. 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One-year follow-up of a series of 100 patients treated for lumbar spinal canal stenosis by means of HeliFix interspinous process decompression device.

Purpose. New interspinous process decompression devices (IPDs) provide an alternative to conservative treatment and decompressive surgery for patients with neurogenic intermittent claudication (NIC) due to degenerative lumbar spinal stenosis (DLSS). HeliFix is a minimally invasive IPD that can be implanted percutaneously. This is a preliminary evaluation of safety and effectiveness of this IPD up to 12 months after implantation. Methods. After percutaneous implantation in 100 patients with NIC due to DLSS, data on symptoms, quality of life, pain, and use of pain medication were obtained for up to 12 months. Results. Early symptoms and physical function improvements were maintained for up to 12 months. Leg, buttock/groin, and back pain were eased throughout, and the use and strength of related pain medication were reduced. Devices were removed from 2% of patients due to lack of effectiveness. Conclusions. Overall, in a period of up to 12-month follow-up, the safety and effectiveness of the HeliFix offered a minimally invasive option for the relief of NIC complaints in a high proportion of patients. Further studies are undertaken in order to provide insight on outcomes and effectiveness compared to other decompression methods and to develop guidance on optimal patient selection.