Category: Spine

Posted on

After 9 Years of 3-Column Osteotomies, Are We Doing Better? Performance Curve Analysis of 573 Surgeries With 2-Year Follow-up

Neurosurgery 83:69–75, 2018

In spinal deformity treatment, the increased utilization of 3-column (3CO) osteotomies reflects greater comfort and better training among surgeons. This study aims to evaluate the longitudinal performance and adverse events (complications or revisions) for a multicenter group following a decade of 3CO.

OBJECTIVE: To investigate if performance of 3CO surgeries improves with years of practice. METHODS:Patientswhounderwent 3COfor spinal deformity with intra/postoperative and revision data collected up to 2 yrwere included. Patientswere chronologically divided into 4 even groups. Demographics, baseline deformity/correction, and surgical metrics were compared using Student t-test. Postoperative and revision rates were compared using Chi-square analysis.

RESULTS: Five hundred seventy-three patients were stratified into: G1 (n=143, 2004-2008), G2 (n = 142, 2008-2009), G3 (n = 144, 2009-2010), G4 (n = 144 2010-2013). The most recent patients were more disabled by Oswestry disability index (G4=49.2 vs G1=38.3, P=.001), and received a larger osteotomy resection (G4 = 26◦ vs G1 = 20◦, P = .011) than the earliest group. There was a decrease in revision rate (45%, 35%, 33%, 30%, P = .039), notably in revisions for pseudarthrosis (16.7% G1 vs 6.9% G4, P = .007). Major complication rates also decreased (57%, 50%, 46%, 39%, P = .023) as did excessive blood loss (>4 L, 27.2 vs 16.7%, P =.023) and bladder/bowel deficit (4.2% vs 0.7% P=.002). Successful outcomes (no complications or revision) significantly increased (P = .001).

CONCLUSION:Over 9 yr, 3COs are being performed on an increasingly disabled population while gaining a greater correction at the osteotomy site. Revisions and complication rate decreased while success rate improved during the 2-yr follow-up period.

Posted on

The subatlantic triangle: gateway to early localization of the atlantoaxial vertebral artery

J Neurosurg Spine 29:18–27, 2018

Exposure of the vertebral artery (VA) between C-1 and C-2 vertebrae (atlantoaxial VA) may be necessary in a variety of pathologies of the craniovertebral junction. Current methods to expose this segment of the VA entail sharp dissection of muscles close to the internal jugular vein and the spinal accessory nerve. The present study assesses the technique of exposing the atlantoaxial VA through a newly defined muscular triangle at the craniovertebral junction.

METHODS Five cadaveric heads were prepared for surgical simulation in prone position, turned 30°–45° toward the side of exposure. The atlantoaxial VA was exposed through the subatlantic triangle after reflecting the sternocleidomastoid and splenius capitis muscles inferiorly. The subatlantic triangle was formed by 3 groups of muscles: 1) the levator scapulae and splenius cervicis muscles inferiorly and laterally, 2) the longissimus capitis muscle inferiorly and medially, and 3) the inferior oblique capitis superiorly. The lengths of the VA exposed through the triangle before and after unroofing the C-2 transverse foramen were measured.

RESULTS The subatlantic triangle consistently provided access to the whole length of atlantoaxial VA. The average length of the VA exposed via the subatlantic triangle was 19.5 mm. This average increased to 31.5 mm after the VA was released at the C-2 transverse foramen.

CONCLUSIONS The subatlantic triangle provides a simple and straightforward pathway to expose the atlantoaxial VA. The proposed method may be useful during posterior approaches to the craniovertebral junction should early exposure and control of the atlantoaxial VA become necessary.

 

Posted on

Impact of local steroid application on dysphagia following an anterior cervical discectomy and fusion: results of a prospective, randomized single-blind trial

J Neurosurg Spine 29:10–17, 2018

Intraoperative local steroid application has been theorized to reduce swelling and improve swallowing in the immediate period following anterior cervical discectomy and fusion (ACDF). Therefore, the purpose of this study was to quantify the impact of intraoperative local steroid application on patient-reported swallow function and swelling after ACDF.

METHODS A prospective, randomized single-blind controlled trial was conducted. A priori power analysis determined that 104 subjects were needed to detect an 8-point difference in the Quality of Life in Swallowing Disorders (SWAL-QOL) questionnaire score. One hundred four patients undergoing 1- to 3-level ACDF procedures for degenerative spinal pathology were randomized to Depo-Medrol (DEPO) or no Depo-Medrol (NODEPO) cohorts. Prior to surgical closure, patients received 1 ml of either Depo-Medrol (DEPO) or saline (NODEPO) applied to a Gelfoam carrier at the surgical site. Patients were blinded to the application of steroid or saline following surgery. The SWAL-QOL questionnaire was administered both pre- and postoperatively. A ratio of the prevertebral swelling distance to the anteroposterior diameter of each vertebral body level was calculated at the involved levels ± 1 level by using pre- and postoperative lateral radiographs. The ratios of all levels were averaged and multiplied by 100 to obtain a swelling index. An air index was calculated in the same manner but using the tracheal air window diameter in place of the prevertebral swelling distance. Statistical analysis was performed using the Student t-test and chi-square analysis. Statistical significance was set at p < 0.05.

RESULTS Of the 104 patients, 55 (52.9%) were randomized to the DEPO cohort and 49 (47.1%) to the NODEPO group. No differences in baseline patient demographics or preoperative characteristics were demonstrated between the two cohorts. Similarly, estimated blood loss and length of hospitalization did not differ between the cohorts. Neither was there a difference in the mean change in the scaled total SWAL-QOL score, swelling index, and air index between the groups at any time point. Furthermore, no complications were observed in either group (retropharyngeal abscess or esophageal perforation).

CONCLUSIONS The results of this prospective, randomized single-blind study did not demonstrate an impact of local intraoperative steroid application on patient-reported swallowing function or swelling following ACDF. Neither did the administration of Depo-Medrol lead to an earlier hospital discharge than that in the NODEPO cohort. These results suggest that intraoperative local steroid administration may not provide an additional benefit to patients undergoing ACDF procedures.

 

Posted on

Total en-bloc spondylectomy through a posterior approach: technique and surgical outcome in thoracic metastases

Acta Neurochirurgica (2018) 160:1373–1376

In 1981, Roy-Camille et al. have firstly reported the total en-bloc spondylectomy (TES) through a posterior approach for cases of malignant spine tumors in order to reduce the local recurrence and to increase the patient’s survival. By then, this surgery has been increasingly gaining recognition. However, it requires a high level of technical ability and knowledge of spinal anatomy, physiology, and biomechanics.

Method Herein, we report the patient’s selection and technique to execute the TES for cases of thoracic metastasis.

Conclusion This surgery is technically demanding so the patient’s selection requires a careful pre-operative evaluation. However, it can be suggested for patients affected by intracompartmental lesions with a good prognosis since the tumor’s progression is “limited” by local barriers as demonstrated by histological studies.

Posted on

Lumbar disk herniation during pregnancy: a review on general management and timing of surgery

Acta Neurochir (2018) 160:1361–1370

Objective Provide an overview of existing management strategies to suggest a guideline for surgical management of lumbar disk herniation in pregnant women based on time of presentation.

Methods We performed a narrative review on the topic using the PubMed database. A total of 63 relevant articles published after 1992 were identified, of which 17 fulfilled selection criteria.

Results A total of 22 published cases of spine surgery for disk herniation during pregnancy were found in 17 studies on the topic. Prone positioning was reported in the majority of cases during the first and early second trimester. C-sections were performed prior to spine surgery in the prone position for the majority of patients operated during the third trimester. The left lateral position with continued pregnancy was preferred during the latter half of the second trimester when delivery of the fetus cannot yet be performed but surgery is indicated.

Conclusion Spine surgery during pregnancy is a rare scenario but can be performed safely when needed if providers adhere to general guidelines. Surgical approaches and overall management are influenced by the stage of pregnancy.

Posted on

Operative Approaches for Lumbar Disc Herniation: A Systematic Review and Multiple Treatment Meta-Analysis of Conventional and Minimally Invasive Surgeries

World Neurosurg. (2018) 114:391-407

Minimally invasive surgery (MIS) techniques have emerged as viable and safe alternatives for lumbar disc herniation, including percutaneous discectomy, percutaneous endoscopic discectomy, and tubulardiscectomy (TD). We present here a systematic review and a multiple-treatment metaanalysis evaluating the operative outcomes and patient-reported outcomes of open/microdiscectomy (OD/MD) and all MIS approaches for lumbar disc herniation.

METHODS: The PICO approach and PRISMA (i.e., Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed to query existing online databases since their inception to 2016, which yielded 14 studies after we applied the inclusion/exclusion criteria. The Cochrane Collaboration’s tool for assessing risk of bias in randomized trials was used to assess the risk of bias in each study was used to assess the risk of bias in each study. Each outcome was assessed across all studies with the GRADE (i.e., Grading of Recommendations, Assessment, Development and Evaluations) criteria.

RESULTS: There were 1707 patients analyzed, with 782 (45.81%) undergoing OD/MD, 491 (28.76%) undergoing TD, 199 (11.65%) undergoing percutaneous endoscopic discectomy, and 235 (13.76%) patients undergoing percutaneous discectomy. TD was found to be associated with significantly worse Oswestry Disability Index scores (mean difference 1.17, P [ 0.03) whereas OD/MD was associated with worse Oswestry Disability Index scores compared with all other approaches (mean difference 2.61, P [ 0.03), significantly longer duration of stay (mean difference 2.96, P [ 0.04), and more blood loss (mean difference 30.53, P < 0.001). In terms of complications, TD was found to be associated with a greater rate of overall complications (odds ratio [OR] 1.49, P [ 0.002), greater incidence of dural tears (OR 1.72 P [ 0.04), and recurrent herniation (OR 2.09, P [ 0.0007). Finally, OD/MD was associated with significantly lower incidence of revision surgery (OR 0.53, P [ 0.0007).

CONCLUSIONS: Our meta-analysis revealed that tubular-discectomy and percutaneous-endoscopic-discectomy, the most commonly employed MIS techniques for discectomy, can be used as safe alternatives for open discectomy depending on the preference of the operating surgeon.

Posted on

Preoperative full-length standing radiographs and revision rates in lumbar degenerative scoliosis

J Neurosurg Spine 28:581–585, 2018

Full-length (36-inch) standing spine radiographs are commonly used by spine surgeons to evaluate patients with lumbar degenerative scoliosis (LDS). Despite this practice, the impact of these images on preoperative decision making and the rate of revision surgery has not been analyzed. The purpose of this study is to determine if preoperative full-length standing spine radiographs improve surgical decision making by decreasing the rate of revision surgery in patients with LDS.

METHODS From the Health Care Service Corporation administrative claims database, the authors identified patients 50–80 years of age with LDS who had undergone surgery including posterior lumbar decompression and fusion over 2–6 levels and with at least 5 years of continuous coverage after the index surgery. Patients were stratified into the following groups, according to the preoperative imaging studies performed within 6 months before their index surgery: lumbar spine MRI studies only, lumbar spine MRI studies and standard lumbar spine radiographs, CT myelograms, and full-length standing spine radiographs. Survival analysis was performed with the occurrence of a revision within 5 years of the index surgery as the outcome of interest.

RESULTS A total of 411 patients were included in the study after applying the inclusion and exclusion criteria. Revision surgery within 5 years after the index procedure was most frequent in the patients with preoperative MRI only (41.8%), followed by the patients with a CT myelogram (30.4%) and those with MRI and standard radiographs (24.8%). The lowest revision rate was seen among those with long-cassette standing radiographs (11.1%). Patients whose preoperative evaluation included full-length standing radiographs (OR 0.353, p = 0.034) and MRI studies plus radiographs (OR 0.650, p = 0.022) were less likely to require revision surgery at 5 years after the index procedure.

CONCLUSIONS An assessment of standing alignment using full-length (36-inch) standing radiographs may be beneficial in reducing the risk of revision surgery in patients with lumbar scoliosis. This observation was not limited to patients with large curves or substantial deformity.

Posted on

State of the Art Treatment of Spinal Metastatic Disease

Neurosurgery 82:757–769, 2018

Treatment paradigms for patients with spine metastases have evolved significantly over the past decade. Incorporating stereotactic radiosurgery into these paradigms has been particularly transformative, offering precise delivery of tumoricidal radiation doses with sparing of adjacent tissues. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional radiation.

The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive, techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity.

Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care, improving both local control and patient survivals. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists, and pain specialists.

This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases, integrating these data into a decision framework, NOMS, which integrates the 4 sentinel decision points in metastatic spine tumors: Neurologic, Oncologic, Mechanical stability, and Systemic disease and medical co-morbidities.

Posted on

Sagittal radiographic parameters demonstrate weak correlations with pretreatment patient-reported health-related quality of life measures in symptomatic de novo degenerative lumbar scoliosis

J Neurosurg Spine 28:573–580, 2018

Previous studies have demonstrated that among patients with adult spinal deformity (ASD), sagittal plane malalignment is poorly tolerated and correlates with suboptimal patient-reported health-related quality of life (HRQOL). These studies included a broad range of radiographic abnormalities and various types of ASD. However, the clinical and radiographic characteristics of de novo degenerative lumbar scoliosis (DNDLS), a subtype of ASD, may influence previously reported correlation strengths. The aim of this study was to correlate sagittal radiographic parameters with pretreatment HRQOL in patients with symptomatic DNDLS.

METHODS In this multicenter retrospective study of prospectively collected data, 74 patients with symptomatic DNDLS were enrolled based on anteroposterior and lateral 36-inch standing radiographs. Measurements included Cobb angle, coronal imbalance, pelvic incidence (PI), pelvic tilt (PT), lumbar lordosis (LL), sagittal vertical axis (SVA), thoracic kyphosis, pelvic incidence minus lumbar lordosis (PI-LL), T1-pelvic angle, and global tilt. HRQOL questionnaires included the Oswestry Disability Index (ODI), Scoliosis Research Society (SRS-22r), 36-item Short-Form Health Survey, and numeric rating scale (NRS) for back and leg pain. Correlations between radiographic parameters and HRQOL were assessed. Finally, HRQOL and increasing severity of sagittal modifiers (SVA, PI-LL, and PT) were evaluated.

RESULTS Weak correlations were found between SVA and ODI (r = 0.296, p < 0.05) and PT with NRS back pain and the SRS pain domain (r = -0.260, p < 0.05, and r = 0.282, p < 0.05, respectively). Other sagittal radiographic parameters did not show any significant correlation with HRQOL. No significant differences in HRQOL were found concerning the increasing severity of PT, PI-LL, and SVA.

CONCLUSIONS While DNDLS is a severe disabling condition, no noteworthy association between clinical and sagittal radiographic parameters was found through this study, demonstrating that sagittal radiographic parameters should not be considered the unique predictor of pretreatment suboptimal health status in this specific group of patients. Future studies addressing classification and treatment algorithms will have to take into account the existing subgroups of ASD.

Posted on

Global Spinal Alignment in Cervical Kyphotic Deformity: The Importance of Head Position and Thoracolumbar Alignment in the Compensatory Mechanism

Neurosurgery 82:686–694, 2018

Previous studies have evaluated cervical kyphosis (C-kypho) using cervical curvature or chin-brow vertical angle, but the relationship between C-kypho and global spinal alignment is currently unknown.

OBJECTIVE: To elucidate global spinal alignment and compensatory mechanisms in primary symptomatic C-kypho using full-spine radiography.

METHODS: In this retrospectivemulticenter study, symptomatic primary C-kypho patients (Cerv group; n=103) and adult thoracolumbar deformity patients (TL group; n=119) were compared.We subanalyzed Cerv subgroups according to sagittal vertical axis (SVA) values of C7 (SVAC7 positive or negative [C7P or C7N]). Various Cobb angles (◦) and SVAs (mm) were evaluated.

RESULTS: SVAC7 values were –20.2 and 63.6 mm in the Cerv group and TL group, respectively (P < .0001). Various statistically significant compensatory curvatures were observed in the Cerv group, namely larger lumbar lordosis (LL) and thoracic kyphosis. The C7N group had significantly lower SVACOG (center of gravity of the head) and SVAC7 (32.9 and –49.5 mm) values than the C7P group (115.9 and 45.1 mm). Sagittal curvatures were also different in T4-12, T10-L2, LL4-S, and LL. The value of pelvic incidence (PI)-LL was different (C7N vs C7P; –2.2◦ vs 9.9◦; P < .0003). Compensatory sagittal curvatures were associated with potential for shifting of SVAC7 posteriorly to adjust head position. PI-LL affected these compensatory mechanisms. CONCLUSION: Compensation in symptomatic primary C-kypho was via posterior shifting of SVAC7, small T1 slope, and large LL. However, even in C-kypho patients, lumbar degeneration might affect global spinal alignment. Thus, global spinal alignment with cervical kyphosis is characterized as head balanced or trunk balanced.

Posted on

Percutaneous Interspinous Spacer vs Decompression in Patients with Neurogenic Claudication

Neurosurgery 82:621–629, 2018

Standalone interspinous process devices (IPDs) to treat degenerative lumbar spinal stenosis with neurogenic intermittent claudication (NIC) have shown ambiguous results in the literature.

OBJECTIVE: To show that a minimally invasive percutaneous IPD is safe and noninferior to standalone decompressive surgery (SDS) for patients with degenerative lumbar spinal stenosis with NIC.

METHODS: A multicenter, international, randomized, controlled trial (RCT) was conducted. One hundred sixty-three patients, enrolled at 19 sites, were randomized 1:1 to treatment with IPD or SDS and were followed for 24 mo.

RESULTS: There was significant improvement in Zurich Claudication Questionnaire physical function, as mean percentage change from baseline, for both the IPD and the SDS groups at 12 mo (primary endpoint) and 24 mo (−32.3 ± 32.1, −37.5 ± 22.8; and −37.9 ± 21.7%, −35.2 ± 22.8, both P < .001). IPD treatment was not significantly noninferior (margin: 10%) to SDS treatment at 12mo (P=.172) but was significantly noninferior at 24mo (P = .005). Symptom severity, patient satisfaction, visual analog scale leg pain, and SF-36 improved in both groups over time. IPD showed lower mean surgical time andmean blood loss (24 ± 11 min and 6 ± 11 mL) compared to SDS (70 ± 39 min and 189 ± 148 mL, both P < .001). Reoperations at index level occurred in 18.2% of the patients in the IPD group and in 9.3%in the SDS group.

CONCLUSION: Confirming 3 recent RCTs, we could show that IPD as well as open decompression achieve similar results in relieving symptoms of NIC in highly selected patients. However, despite some advantages in secondary outcomes, a higher reoperation rate for IPD is confirmed.

Posted on

Prognostic Factors for Satisfaction After Decompression Surgery for Lumbar Spinal Stenosis

Neurosurgery 82:645–651, 2018

Surgical treatment for lumbar spinal stenosis is associated with both short- and long-term benefits with improvements in patient function and pain. Even though most patients are satisfied postoperatively, some studies report that up to onethird of patients are dissatisfied.

OBJECTIVE: To present clinical outcome data and identify prognostic factors related to patient satisfaction 1 yr after posterior decompression surgery for lumbar spinal stenosis.

METHODS: This multicenter register study included 2562 patients. Patients were treated with various types of posterior decompression. Patients with previous spine surgery or concomitant fusion were excluded. Patient satisfaction was analyzed for associations with age, sex, body mass index, smoking status, duration of pain, number of decompressed vertebral levels, comorbidities, and patient-reported outcome measures,which were used to quantify the effect of the surgical intervention.

RESULTS: At 1-yr follow-up, 62.4% of patients were satisfied but 15.1% reported dissatisfaction. The satisfied patients showed significantly greater improvement in all outcome measures compared to the dissatisfied patients. The outcome scores for the dissatisfied patients were relatively unchanged or worse compared to baseline. Association was seen between dissatisfaction, duration of leg pain, smoking status, and patient comorbidities. Patients with good walking capacity at baseline were less prone to be dissatisfied compared to patients with poor walking capacity.

CONCLUSION: This study found smoking, long duration of leg pain, and cancerous and neurological disease to be associated with patient dissatisfaction, whereas good walking capacity at baseline was positively associated with satisfaction after 1 yr.

Posted on

Can patients with symptomatic Tarlov cysts be differentiated from patients with specific low back pain based on comprehensive history taking?

Acta Neurochirurgica (2018) 160:839–844

Tarlov cysts (TCs) are expanded nerve root sheaths that occur near the dorsal root ganglion and result from increased intraspinal hydrostatic pressure. TCs most frequently affect the lumbosacral plexus and therefore may cause specific symptoms such as perineal pain and neurogenic bladder, bowel, and sphincter problems. It has been estimated that 1% of the population has symptomatic Tarlov cysts (STCs). However, STCs appear to be underdiagnosed, with the pain reported by patients commonly attributed to degenerative alterations seen on MRI. The aim of the present study is to investigate the utility of a comprehensive questionnaire for use by physicians in establishing the diagnosis of STCs.

Methods We compared questionnaire responses regarding patient history between 33 patients diagnosed with symptomatic TCs and 42 patients with chronic low back pain and sciatica due to disc problems or degenerative or inflammatory disorders. The diagnosis of STCs was confirmed using nerve conduction studies (NCS) and electromyography (EMG) of the sacral myotomes by an expert neurophysiologist.

Results The questionnaire responses revealed specific differences in perineal symptoms (perineal pain, dyspareunia, coccygodynia), bowel symptoms (constipation, diarrhea), bladder symptoms (hesitation, retention, frequency), and anal sphincter problems (anal pain, mild fecal incontinence). Additionally, sitting, walking, and straining aggravated pain more frequently in STC patients, and STC patients were more often forced to stop working and/or reduce their social activities.

Conclusions Including the above-listed items in the patient history might facilitate differentiation of low back pain and sciatica due to STCs from that due to disc problems or degenerative or inflammatory disorders.

Posted on

Is Eighty the New Sixty? Outcomes and Complications after Lumbar Decompression Surgery in Elderly Patients over 80 Years of Age

World Neurosurg. (2018) 112:e555-e560.

An increasing demographic aging of the general population results in a rising incidence of octogenarians and nonagenarians with spine disease. Patients older than 65 years represent the majority of patients with degenerative lumbar spine disease in our daily clinical routine. Surgical treatment is undertaken reluctantly because of an increased rate of comorbidities. We therefore assessed complication rates of lumbar decompression in regard to neurological outcome and medical conditions in patients age 80 years or older in a retrospective singlecenter series.

METHODS: Data for 244 patients (124 female, 120 male; mean age, 83.1  3 years; age range, 80e95 years) who underwent decompressive surgery for lumbar spinal stenosis or disc herniation between April 2007 and February 2016 were assessed retrospectively. Age at surgery, neurologic deficits (preoperative and postoperative), relevant medical comorbidities and previous lumbar decompression, intraoperative and postoperative complications (e.g., surgery-related, medical), duration of surgery, length of hospital stay, and rate of revision surgeries were recorded.

RESULTS: Surgery was performed for lumbar stenosis (184 patients; 75.4%), lumbar disc herniation (13 patients; 5.3%) or both (47 patients; 19.3%). Seventy-six patients (31.3%) patients experienced preoperative neurologic deficits; 48 (63.2%) of these patients improved, 28 (36.8%) of them were unchanged after surgery, and none deteriorated. New transient, postoperative, neurologic deficits occurred in 6 patients (2.5%). All 55 (22.5%) intraoperative complications were mild to moderate, and no severe surgical complications occurred. Two hundred fifteen patients (88%) had relevant medical disorders. Nineteen (7.7%) postoperative medical complications were reported in 17 patients (7%), of which 14 (73.7%) were severe and 5 (26.3%) were mild (4 pulmonary embolisms, 6 pneumonias, 3 myocardial infarctions, 1 postoperative renal failure, 5 urinary tract infections). Medical complications that necessitated intensive care unit treatment and resulted in lethal outcome were seen in 2 patients (0.8%).

CONCLUSION: Despite their age, the vast majority of octogenarians and nonagenarians benefited from lumbar decompression surgery. Mild to moderate intraoperative complications were relatively frequent, whereas severe intraoperative complications did not occur. The majority of medical complications was severe, but the incidence was acceptable, and the postoperative outcome was still favorable in most patients

Posted on

Incidence and clinical relevance of cage subsidence in anterior cervical discectomy and fusion

Acta Neurochirurgica (2018) 160:873–880

The placement of intervertebral cages in anterior cervical discectomy (ACDF) supposedly maintains foraminal height. The most commonly reported cage-related complication is subsidence, although it is unknown whether a correlation between subsidence and clinical outcome exists. Aim To assess the incidence and relevance of subsidence.

Methods Literature searches were performed in PubMed, MEDLINE, Embase,Web of Science, COCHRANE, and CENTRAL. The inclusion criteria were as follows: ≥ 20 patients, ADCF with cage, subsidence assessed, and primary data. Risk of bias was assessed using adjusted Cochrane checklists.

Results Seventy-one studies, comprising 4784 patients, were included. Subsidence was generally defined as ≥ 3-mm loss of height comparing postoperative intervertebral heights with heights at last follow-up. Mean incidence of subsidence was 21% (range 0–83%). Of all patients, 46% of patients received polyether-ether-ketone (PEEK) cages, 31% received titanium cages, 18% received cage-screw-combinations, and 5% received polymethyl-methacrylate (PMMA) cages. Patients treated with cagescrew- combinations had significantly less subsidence than patients treated with PEEK, titanium, or PMMA cages (15.1% vs. 23.5% vs. 24.9% vs. 30.2%; p < 0.001). Thirteen studies assessed clinical outcome in relation to subsidence; the majority did not find a significant correlation. Only four studies correlated subsidence to cage size and/or height; no correlation was established.

Conclusions Subsidence in ACDF with cages occurs in 21% of patients. The risk for subsidence seems lower using PEEK or titanium cages or adding screws.Whether subsidence affects clinical outcome is not satisfactorily evaluated in the available literature. Future studies on this correlation are warranted in order to establish the additional value of the interposition of a cage in ACDF.

Posted on

Endplate changes after lumbar discectomy with and without implantation of an annular closure device

Acta Neurochirurgica (2018) 160:855–862

The implantation of a bone-anchored annular closure device (ACD) might be associated with the developed new endplate changes (EPC) after surgery.

Methods A post hoc analysis has been done in patients from a prospective randomized multicenter study. All patients underwent limited lumbar discectomy with intraoperative randomization into the groups limited lumbar discectomy alone or additional ACD implantation. Low-dose lumbar computed tomography (CT) and clinical investigations were performed preoperatively and 12 months after the operation.

Results A total of 554 patients were randomized. After exclusion of dropouts, the per-protocol population included 493 patients (251 in the control group and 242 in the ACD group); the follow-up rate was ≥ 90%. The number of patients showing EPC at baseline was similar in both groups. The number of patients showing EPC and the total EPC lesion area significantly increased in both groups over time, but significantly increased more in the EPC group for the superior and inferior endplate (all P < 0.0001). There was no association of pre-existing number and size of EPC with sex, age, or smoking habits. Correlation of clinical variables showed no relation with number, size, and increase of EPC area after surgery.

Conclusions Patients with primary lumbar disc herniation show EPC in the corresponding segments. There is a significant increase of lesion number and size within 12 months after discectomy. This increase is significantly more pronounced in the ACD group. Presence and growth of EPC is not correlated with low-back pain or ODI.

Posted on

Management of Odontoid Fractures in the Elderly

Neurosurgery 82:419–430, 2018

Odontoid fractures are the most common fracture of the axis and the most common cervical spine fracture in patients over 65. Despite their frequency, there is considerable ambiguity regarding optimal management strategies for these fractures in the elderly. Poor bone health and medical comorbidities contribute to increased surgical risk in this population; however, nonoperative management is associated with a risk of nonunion or fibrous union.

We provide a review of the existing literature and discuss the classi- fication and evaluation of odontoid fractures. The merits of operative vs nonoperative management, fibrous union, and the choice of operative approach in elderly patients are discussed. A treatment algorithm is presented based on the available literature.

We believe that type I and type III odontoid fractures can be managed in a collar in most cases. Type II fractures with any additonal risk factors for nonunion (displacement, comminution, etc) should be considered for surgical management. However, the risks of surgery in an elderly population must be carefully considered on a case-by-case basis. In a frail elderly patient, a fibrous nonunion with close follow-up is an acceptable outcome. If operative management is chosen, a posterior approach is should be chosen when fracture- or patient-related factors make an anterior approach challenging.

The high levels of morbidity and mortality associated with odontoid fractures should encourage all providers to pursue medical co- management and optimization of bone health following diagnosis.

Posted on

Prospective, randomized, multicenter study with 2-year follow-up to compare the performance of decompression with and without interlaminar stabilization

J Neurosurg Spine 28:406–415, 2018

Surgical decompression is extremely effective in relieving pain and symptoms due to lumbar spinal stenosis (LSS). Decompression with interlaminar stabilization (D+ILS) is as effective as decompression with posterolateral fusion for stenosis, as shown in a major US FDA pivotal trial. This study reports a multicenter, randomized controlled trial in which D+ILS was compared with decompression alone (DA) for treatment of moderate to severe LSS.

METHODS Under approved institutional ethics review, 230 patients (1:1 ratio) randomized to either DA or D+ILS (coflex, Paradigm Spine) were treated at 7 sites in Germany. Patients had moderate to severe LSS at 1 or 2 adjacent segments from L-3 to L-5. Outcomes were evaluated up to 2 years postoperatively, including Oswestry Disability Index (ODI) scores, the presence of secondary surgery or lumbar injections, neurological status, and the presence of device- or procedure-related severe adverse events. The composite clinical success (CCS) was defined as combining all 4 of these outcomes, a success definition validated in a US FDA pivotal trial. Additional secondary end points included visual analog scale (VAS) scores, Zürich Claudication Questionnaire (ZCQ) scores, narcotic usage, walking tolerance, and radiographs.

RESULTS The overall follow-up rate was 91% at 2 years. There were no significant differences in patient-reported outcomes at 24 months (p > 0.05). The CCS was superior for the D+ILS arm (p = 0.017). The risk of secondary intervention was 1.75 times higher among patients in the DA group than among those in the D+ILS group (p = 0.055). The DA arm had 228% more lumbar injections (4.5% for D+ILS vs 14.8% for DA; p = 0.0065) than the D+ILS one. Patients who underwent DA had a numerically higher rate of narcotic use at every time point postsurgically (16.7% for D+ILS vs 23% for DA at 24 months). Walking Distance Test results were statistically significantly different from baseline; the D+ILS group had > 2 times the improvement of the DA. The patients who underwent D+ILS had > 5 times the improvement from baseline compared with only 2 times the improvement from baseline for the DA group. Foraminal height and disc height were largely maintained in patients who underwent D+ILS, whereas patients treated with DA showed a significant decrease at 24 months postoperatively (p < 0.001).

CONCLUSIONS This study showed no significant difference in the individual patient-reported outcomes (e.g., ODI, VAS, ZCQ) between the treatments when viewed in isolation. The CCS (survivorship, ODI success, absence of neurological deterioration or device- or procedure-related severe adverse events) is statistically superior for ILS. Microsurgical D+ILS increases walking distance, decreases compensatory pain management, and maintains radiographic foraminal height, extending the durability and sustainability of a decompression procedure. Clinical trial registration no.: NCT01316211 (clinicaltrials.gov)

 

Posted on

Modified Laminoplasty Preserving the Posterior Deep Extensor Insertion into C2 Improves Clinical and Radiologic Results Compared with Conventional Laminoplasty: A Meta-Analysis

World Neurosurg. (2018) 111:157-165

Whether modified laminoplasty is better than conventional laminoplasty is unclear. Thus, a meta-analysis comparing the outcomes of preserving or repairing the posterior deep extensor insertion to C2 in laminoplasty was conducted for patients with multilevel cervical spondylotic myelopathy (MCSM).

METHODS: Several electronic databases were chosen to search for relevant studies. The primary indices included preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, JOA recovery rate, muscle atrophy rate, preoperative and postoperative range of motion (ROM), ROM decrease rate, and incidence of axial pain. Results are expressed as odds ratios with 95% confidence intervals for the dichotomous outcomes and mean differences for continuous outcomes.

RESULTS: Eight studies involving 763 patients were included in this study. The postoperative cervical ROM was significantly higher in the modified group (P [ 0.01, MD [ 3.0 [0.66, 5.35]), as was the cervical posterior muscle volume (P [ 0.02, MD [ 28.28 [4.42, 52.3]) and the operation time (MD [ L45.04, 95% CI L49.79, L40.29; P < 0.01). The incidence of axial symptoms in the modified group was lower than that in the conventional group (P < 0.01, OR 0.28 [0.17, 0.46]), as was the rate of decrease of cervical ROM (P [ 0.004, MD [ L6.72 [L11.25, 2.19]). There was no significant difference (P > 0.05) between the groups in blood loss, preoperative and postoperative JOA score, or JOA recovery rate.

CONCLUSIONS: Modified laminoplasty had shorter operation times, a lower incidence of axial pain, a higher cervical ROM, and a lower atrophy rate compared with conventional laminoplasty. The clinical and radiologic results of modified laminoplasty have been partly superior to those of conventional laminoplasty to date.

Proudly powered by WordPress