Single-level Degenerative Disc Disease Research Articles

Correlation of Foraminal Parameters with Patient-Reported Outcomes in Patient with Degenerative Lumbar Foraminal Stenosis.

The relationship between quantitative anatomic parameters in MRI and patient-reported outcomes (PROs) before and after surgery in degenerative lumbar foraminal stenosis remains unknown. We included 58 patients who underwent transforaminal lumbar interbody fusion (TLIF) for single-level degenerative disc disease with foraminal stenosis between February 2013 and June 2020. PROs were evaluated using the visual analog scale (VAS) for back and leg pain, Oswestry Disability Index (ODI), and EuroQol-5D (EQ-5D). The foraminal parameters assessed using preoperative MRI included foraminal height, posterior intervertebral disc height, superior and inferior foraminal width, and foraminal area. The correlation between foraminal parameters and PROs before operation, at 1 year follow-up, and change from baseline were assessed. The associations between the aforementioned parameters were examined using linear regression analysis. The analysis revealed that among these parameters, superior foraminal width was found to be significantly correlated with ODI and EQ-5D at the 1 year follow-up and with change in ODI and EQ-5D from baseline. The associations remained significant after adjustment for confounding factors including age, sex, body mass index, and duration of hospital stay. The results indicated that in degenerative lumbar foraminal stenosis, decreased superior foraminal width was associated with better improvement in disability and quality of life after TLIF.

Comparison of clinical outcomes between cervical disc arthroplasty and anterior cervical discectomy and fusion for the treatment of single-level cervical spondylosis: a 10-year follow-up study

BACKGROUND CONTEXTThe theoretical advantage of cervical disc arthroplasty includes preserved motion at the cervical level, which may reduce degeneration of the adjacent segments. The long-term follow-up results are still controversial. PURPOSEThe present study aimed to retrospectively study the long-term efficacy and complications of cervical disc arthroplasty using a single commercially-available device in a single center. STUDY DESIGNThis was a propensity-score matched cohort study. PATIENT SAMPLEThis study enrolled 148 single-level cervical degenerative disease patients from January 2009 to March 2012. After 1:1 propensity score matching, 39 patients remained in the ACDF or ACDR groups. OUTCOME MEASURESThe outcome measures were neurological functions (Neck Disability Index (NDI) and Japan Orthopedic Association (JOA) scores), radiographic evaluations (cervical curvature, operative segment range of motion, degenerative condition of adjacent segments, heterotopic ossification (HO) of the surgical segment), and complications. METHODSNDI and JOA scores were used to evaluate patient neurological functions. Cervical curvature (C2-C7 Cobb angle) and operative segment range of motion (ROM) were compared between the two groups. Grading criteria for osteophyte formation were used to evaluate the degenerative condition of adjacent segments. HO after ACDR was graded according to the McAfee grading method. RESULTSThe average follow-up time was 119.3 ±17.2 months. Satisfactory improvements in neurological function were obtained for both the ACDR and ACDF groups. There were no significant differences in VAS or NDI scores between the two groups. In the ACDR group, the ROM of the operative segment increased from 6.7 ±4.3° before the operation to 8.9 ±3.5° on the second day after the operation (p<.001). The ROM of the operative segment was 8.1 ±4.0° at the 1-year follow-up, 7.2 ±3.6° at the 2-year follow-up, 5.7 ±4.5° at the 5-year follow-up and 4.3 ±3.9° at the last follow-up. ASD was more likely to develop in the caudal adjacent segments and progressed with the follow-up time. At the last follow-up, HO was present in 27 patients (69.23%), while high-grade HO (McAfee scores III and IV) was detected in 6 patients (15.38%). CONCLUSIONSThrough nearly 10 years of follow-up, ACDR was as effective as ACDF for treating single-level degenerative cervical disc disease. However, HO and the role of ACDR in the protection of ASD remains to be further observed and followed up.

Single-Level Total Disc Replacement: Index-Level and Adjacent-Level Revision Surgery Incidence, Characteristics, and Outcomes.

The literature reports that index level (IL) revision spine surgery (RSS) and adjacent level (AL) RSS are diminished in lumbar TDR compared with fusion procedures. There is a paucity of PROMs reported after RSS. To present the incidence of RSS at the IL and AL following single-level lumbar total disc replacement (TDR) and to document patient-related outcome measures (PROMs) associated with RSS. PROMs and timelines were analyzed for 32 RSS patients from a prospective cohort study of 401 patients treated with TDR for single-level degenerative disc disease. The data collected prospectively are analyzed from baseline (prior to index surgery) to latest follow-up following RSS. PROMs, including visual analog scales for back and leg, Oswestry Disability Index, and Roland-Morris Disability Questionnaire, were collected preoperatively; postoperatively at 3, 6, and 12 months; and annually thereafter until RSS. The time to RSS was recorded, and PROMs for RSS (IL, AL, or both) were documented, analyzed, and compared. The median time to RSS in the IL cohort was 35 months (interquartile range [IQR] = 9-51 months). The median time to RSS cohort was 70 months (IQR = 41.3-105.3 months). Timepoints facilitate PROM discussion for RSS. Patients in both groups achieved thresholds for the minimum clinically important difference for pain and disability scores. The small sample size in each group contributed to the variability demonstrated by the 95% CIs, thereby cautioning definitive conclusions. This study reveals that statistically significant and modest clinical improvements in PROMs can be achieved in RSS for lumbar TDR at IL and AL. The surgical approach and technique are reflective of the pathology and suggest that anterior RSS for AL degeneration and posterior RSS for IL pathology yield similar results. Statistical and clinical improvements can be achieved in IL-RSS and AL-RSS following single level TDR. It is essential for clinicians to understand and verify the underlying IL and/or AL pathology to select an appropriate management strategy and to facilitate balanced informed discussions with patients.

Comparison of Mid- to Long-term Follow-up of Patient-reported Outcomes Measures After Single-level Lumbar Total Disc Arthroplasty, Multi-level Lumbar Total Disc Arthroplasty, and the Lumbar Hybrid Procedure for the Treatment of Degenerative Disc Disease.

Prospective cohort study. The aim of this article is to compare the mid- to long-term patient-reported outcome measures (PROMs) between single-level total disc arthroplasty (TDA), multi-level TDA, and hybrid constructs (combination of TDA and anterior lumbar interbody fusion [ALIF] across multiple levels) for symptomatic degenerative disc disease (DDD). The treatment of single-level DDD is well documented using TDA. However, there is still a paucity of published evidence regarding long-term outcomes on multi-level TDA and hybrid constructs for the treatment of multi-level DDD, as well as lack of long-term comparisons regarding treatment of single-level DDD and multi-level DDD. A total of 950 patients underwent surgery for single-level or multi-level DDD between July 1998 and February 2012 with single-level TDA (n = 211), multi-level TDA (n = 122), or hybrid construct (n = 617). Visual Analog Score for the back (VAS-B) and leg (VAS-L) were recorded, along with the Oswestry Disability Index (ODI) and Roland Morris Disability Questionnaire (RMDQ). All PROMs in all groups showed statistically and clinically significant improvements (P < 0.005) in pain and function that is well above the corresponding minimum clinically important difference (MCID) and exceeds literature thresholds for substantial clinical benefit (SCB). Unadjusted analyses show that there were no statistically significant differences in the change scores between the surgery groups for VAS back and leg pain, and RMDQ up to 8 years' follow-up. Adjusted analyses showed the ODI improvement score for the single group was 2.2 points better (95% confidence interval [CI]: 0.6-3.9, P = 0.009) than in the hybrid group. The RMDQ change score was better in the hybrid group than in the multi-level group by 1.1 points (95% CI: 0.4-1.9, P = 0.003) at 6 months and a further 0.4 point at 2 years (95% CI: 0.1-0.8, P = 0.011). In the setting of meticulous preoperative evaluation in establishing a precision diagnosis, clinically and statistically equivalent results can be achieved when treating symptomatic DDD through single-level TDA, multi-level TDA, and hybrid constructs. These results are sustained at mid- to long-term follow-up.Level of Evidence: 3.

Final Long-Term Reporting from a Randomized Controlled IDE Trial for Lumbar Artificial Discs in Single-Level Degenerative Disc Disease: 7-Year Results.

This study compared 7-year safety and efficacy outcomes of activL and ProDisc-L lumbar total disc replacements in patients with symptomatic, single-level lumbar degenerative disc disease (DDD). The objectives are to report 7-year outcomes of the trial, evaluate the outcomes for patients lost to follow-up, and determine whether early outcomes predict long-term outcomes. This was a prospective, multicenter, randomized, controlled investigational device exemption study. Eligible patients with symptomatic, single-level lumbar DDD had failed ≥6 months of nonsurgical management. Patients (N = 283) were randomized to receive activL (n = 218) or ProDisc-L (n = 65). At 7 years, data were available from 206 patients (activL, 160; ProDisc-L, 46). Logistic regression models were fit to predict 7-year outcomes for patients lost to follow-up after 2 years. At 7 years, the activL group was noninferior to the ProDisc-L group on the primary composite endpoint (P = .0369). Both groups showed significant reductions in back/leg pain severity and improvements in disability index and quality-of-life relative to baseline (P < .0001). In both groups, opioid use was significantly reduced at 7 years (0%) relative to baseline (P < .01), and the overall reoperation rates were low (4.6%). activL patients showed a significantly better range of motion (ROM) for flexion-extension rotation than ProDisc-L patients (P = .0334). A significantly higher proportion of activL patients did not report serious adverse events (activL, 62%; ProDisc-L, 43%; P = .011). Predictive modeling indicated that >70% of patients (depending on outcome) lost to follow-up after 2 years would show clinically significant improvement at 7 years if improvements were achieved at 2 years. The benefits of activL and ProDisc-L are maintained after 7 years, with significant improvements from baseline observed in pain, function, and opioid use. activL is more effective at preserving ROM than ProDisc-L and has a more favorable safety profile. Improvements in other primary and secondary outcomes were similar between both disc designs. 1.

Outcome of Tantalum Cage in Posterior Lumbar Interbody Fusion in Lumbar Degenerative Disc Disease and Low-grade Spondylolisthesis

Background Data: Posterior lumbar interbody fusion (PLIF) provides better stability and fusion as a surgical treatment for degenerative disc disease (DDD) and spondylolisthesis. Different cage designs are available for interbody fusion. Tantalum cages are recent and appealing options in these techniques. Purpose: To assess the clinical and radiological outcome of tantalum interbody cage in PLIF without autologous bone graft inside the cage. Study Design: A retrospective case series study. Patients and Methods: A total of 25 patients with single-level DDD (n = 16) or spondylolisthesis (n = 9) who underwent single-level PLIF surgeries with 1-year follow-up were recruited for this study. Clinical and functional assessment was done using the visual analogue scale (VAS) for low back pain and Oswestry Disability Index (ODI). Tantalum cage stability and fusion were assessed radiologically on static and dynamic lateral X-ray. Results: VAS and ODI showed significant postoperative improvement at 6-week and 3-, 6-, and 12-month follow-up intervals. No significant migration or subsidence of tantalum cage was reported on static X-ray, no significant mobility was reported on dynamic X-ray, and the total sound bone fusion rate was 96% at 1-year follow-up. Conclusion: Our data suggest that PLIF with tantalum interbody cage in lumbar DDD and low-grade spondylolisthesis showed good clinical and functional results in 1-year follow-up with high spinal stability and bone fusion rate (2020ESJ225).

Long-Term Clinical Outcomes With the Activ-L Lumbar Arthroplasty System.

Low back pain (LBP) due to degenerative disc disease (DDD) is the most common occupational disorder worldwide. Lumbar total disc replacement (LTDR) has provided an alternative to rigid fusion to relieve pain with less motion restriction. We present clinical results with long-term follow-up from a single-center, single-surgeon series of patients treated with the Activ-L artificial disc. Thirty-three patients with symptomatic single-level DDD who failed nonsurgical therapy for a minimum of 6 months underwent single-level arthroplasty with the Activ-L system between 2007 and 2012. Demographic, preoperative, and postoperative data were collected prospectively. Clinical factors reviewed included occupational status, sensory deficits, functional status determined by Oswestry Disability Index (ODI), back pain, leg pain, pain medication consumption, and radiographic imaging. Average age at surgery was 38.0 ± 7.8 years, and the majority of patients were male (60.6%). Average follow-up was 2.7 ± 1.7 years. Average ODI at preoperative baseline was 54.6 ± 13.5, with scores significantly improved at 6 weeks (28.6 ± 17.4, P < .0001), 3 months (24.1 ± 16.8, P < .0001), 6 months (22.3 ± 16.3, P < .0001), 1 year (18.8 ± 15.3, P < .0001), and final follow-up (15.6 ± 16.4, P < .0001). Most patients (87.8%) reported pain medication usage within 14 days of baseline evaluation, with consumption decreasing significantly at 1-year (34.5%, P < .0001) and long-term follow-up (21.2%, P < .0001). One patient experienced mild unilateral graft subsidence at 1 year, which remained stable on radiographs at 5 years. None of the prostheses required revision surgery. The Activ-L disc replacement system is safe and effective for treating single-level lumbar DDD. Patients reported significant improvement in functional outcomes and decreases in pain medication consumption. Further investigation of the Activ-L system in larger populations is warranted. LBP is a common cause of disability worldwide, and better treatment options are needed to improve outcomes, including pain and mobility. Spine surgeons may choose the Activ-L disc replacement as a safe and effective treatment for LBP caused by single-level lumbar DDD.

The Functional outcome following anterior cervical discectomy and fusion for single level cervical degenerative disc disease: a prospective single institutional study

Introduction: Cervical degenerative disc diseases leading to cervical spondylotic myelopathy (CSM) is one the most common cause of disability in elderly population that progresses with age with continuation of degree of degeneration.&#x0D; Objective: To assess the functional outcome following ACDF in single-level cervical degenerative disc disease in terms of improvement in the mJOA scoring system and postoperative complications.&#x0D; Materials and methods: Eighteen patients with single level cervical degenerative disc diseases who presented at the college of medical sciences from May 2018 to October 2019 fulfilling the inclusion criteria (single-level cervical degenerative disc disease with age between 40 to 70 years with progressive neurological deficits, features of cervical spondylotic myelopathy and patients with mild grade who failed four weeks of conservative treatment and progressed to moderate or severe grades) were included in the study. All patients underwent Anterior Cervical Discectomy and Fusion (ACDF); with tricortical iliac crest graft with cervical plate and screws in 13 patients and polyether ether ketone (PEEK) cage placement in five patients. Patients were assessed using mJOA scoring system and graded into mild, moderate and severe myelopathy. Post-operatively patients were assessed for improvement in terms of mJOA scores at four weeks and three months follow-up. They were also assessed for development of any post-operative complications and documented accordingly. Statistical analysis was done using the Statistical Package for the Social Sciences version 20 software.&#x0D; Results: Out of 18 patients, at the time of presentation 12 were in moderate grade and six were in severe grade. During subsequent follow up at four weeks and three months, patients showed progressive improvement. 15 patients improved to mild grade while two remained in moderate grade and one in severe grade during three months postoperative assessment. One patient each developed dysphagia, hoarseness and superficial wound infection that were managed conservatively.&#x0D; Conclusion: Anterior cervical discectomy and fusion is one of the effective and safe treatments for single-level degenerative cervical disc disease associated with cervical spondylotic myelopathy with minimal complications.

Two-Year Clinical and Radiological Outcomes in Patients With Diabetes Undergoing Single-Level Anterior Cervical Discectomy and Fusion.

Study Design:Secondary analysis of data from the multicenter, randomized, parallel-controlled Food and Drug Administration (FDA) investigational device exemption study.Objective:Studies on outcomes following anterior cervical discectomy and fusion (ACDF) in individuals with diabetes are scarce. We compared 24-month radiological and clinical outcomes in individuals with and without diabetes undergoing single-level ACDF with either i-FACTOR or local autologous bone.Methods:Between 2006 and 2013, 319 individuals with single-level degenerative disc disease (DDD) and no previous fusion at the index level underwent ACDF. The presence of diabetes determined the 2 cohorts. Data collected included radiological fusion evaluation, neurological outcomes, Neck Disability Index (NDI), Visual Analog Scale (VAS) scores, and the 36-Item Short Form Survey Version 2 (SF-36v2) Physical and Mental component summary scores.Results:There were 35 individuals with diabetes (11.1%; average body mass index [BMI] = 32.99 kg/m2; SD = 5.72) and 284 without (average BMI = 28.32 kg/m2; SD = 5.67). The number of nondiabetic smokers was significantly higher than diabetic smokers: 73 (25.70%) and 3 (8.57%), respectively. Preoperative scores of NDI, VAS arm pain, and SF-36v2 were similar between the diabetic and nondiabetic participants at baseline; however, VAS neck pain differed significantly between the cohorts at baseline (P = .0089). Maximum improvement for NDI, VAS neck and arm pain, and SF-36v2 PCS and MCS scores was seen at 6 months in both cohorts and remained stable until 24 months.Conclusions:ACDF is effective for cervical radiculopathy in patients with diabetes. Diabetes is not a contraindication for patients requiring single-level surgery for cervical DDD.

Long-Term Comparison of Health Care Utilization and Reoperation Rates in Patients Undergoing Cervical Disc Arthroplasty and Anterior Cervical Discectomy and Fusion for Cervical Degenerative Disc Disease

Thus study was a retrospective cohort analysis. Anterior cervical discectomy and fusion (ACDF) has been the gold-standard procedure for single-level degenerative disc disease (DDD). Recently, cervical disc arthroplasty (CDA) has become increasingly prevalent as an alternative intervention. To examine the long-term costs and reoperation rates associated with CDA and ACDF for the treatment of single-level DDD. In the present study, we performed a retrospective cohort analysis using the MarketScan database of patients who underwent either ACDF or CDA between 2007 and 2011 and had 5 years postsurgery follow-up. Outcomes related to the health care utilization, cost, and reoperation were analyzed after propensity score matching (PSM). Of 12,434 patients, 12,099 underwent ACDF and 335 CDA. Length of hospital stay and initial hospitalization cost was higher after ACDF compared with CDA. More patients undergoing CDA had early physical therapy compared with patients undergoing ACDF (CDA 30.15% vs. ACDF 22.39%; P= 0.0176). Five years after surgery, there was no significant difference in overall payments between patients undergoing ACDF and patients undergoing CDA. Reoperation rates were comparable at 5 years after the index procedure (CDA 8.06% vs. ACDF 9.25%; P= 0.5862). Patients who underwent ACDF showed decreased use of tramadol after surgery (15.09% before surgery vs. 9.55% after surgery; P < 0.0001). We found no difference in health care utilization between ACDF and CDA procedures for DDD 5 years after surgery. Also, there was no difference in reoperation rates during the study period. ACDF resulted in significant reduction in overall opioid use after versus before procedure.

Patient-Reported Outcome Measures After Multilevel Lumbar Total Disc Arthroplasty for the Treatment of Multilevel Degenerative Disc Disease.

Case series OBJECTIVE.: The aim of this study was to assess the patient-reported outcome measures (PROMs) and patient satisfaction of multilevel lumbar total disc arthroplasty (TDA) for symptomatic multilevel degenerative disc disease (MLDDD). TDA has been shown to be safe and effective for the treatment of symptomatic single level degenerative disc disease. There is minimal PROMs data on the mid- to long-term outcomes of multilevel TDA constructs. Prospectively collected PROMs were analyzed from patients receiving multilevel TDA for symptomatic MLDDD. Data were collected preoperatively and postoperatively at 3, 6, and 12 months, then yearly. PROMs included patient satisfaction, Visual Analog Score back and leg, Oswestry Disability Index, and Roland-Morris Disability Questionnaire. One hundred twenty-two patients (77 men, 45 women) who had preoperative and at least 24-month follow-up data were included. The average age was 42 ± 8.2 years (range 21-61) and mean follow-up 7.8 years (range 2-10). The majority received two-level TDA, except two patients (1.6%) who received three-level TDA. The two- to three-level TDA's were at the levels L3-4, L4-5, and L5-S1, whereas most two levels (n = 110, 90.2%) were at L4-5 and L5-S1; the remainder (n = 10, 8.2%) being at L3-4 and L4-5. Implants used were Charité (DePuy Spine, Raynham, MA) in 119 patients (240 levels) and InMotion (DePuy Spine) in 3 patients (6 levels). Improvement in pain and disability scores were both clinically and statistically significant (P < 0.001), and this improvement was sustained in those patients over the course of their follow-up. Ninety-two percent of patients reported good or excellent satisfaction with treatment at final review. Multilevel TDA constructs for MLDDD demonstrate favorable and sustained clinical outcomes at mid- to long-term follow-up. 4.

Lumbar disc arthroplasty versus anterior lumbar interbody fusion: 5-year outcomes for patients in the Maverick disc investigational device exemption study.

Despite evidence of its safety and effectiveness, the use of lumbar disc arthroplasty has been slow to expand due in part to concerns about late complications and the risks of revision surgery associated with early devices. More recently, FDA approval of newer devices and improving reimbursements have reversed this trend in the United States. Additional long-term data on lumbar disc arthroplasty are still needed. This study reports the 5-year results of the FDA investigational device exemption clinical trial of the Medtronic Spinal and Biologics' Maverick total disc replacement. Patients with single-level degenerative disc disease from L4 to S1 were randomized 2:1 at 31 investigational sites. In the period from April 2003 to August 2004, 405 patients received the investigational device and 172 patients underwent the control procedure of anterior lumbar interbody fusion. Outcome measures included the Oswestry Disability Index (ODI), numeric rating scales (NRSs) for back and leg pain, the SF-36, disc height, interbody motion, heterotopic ossification (investigational device), adverse events (AEs), additional surgeries, and neurological status. Treatment was considered an overall success when all of the following criteria were met: 1) ODI score improvement ≥ 15 points over the preoperative score; 2) maintenance or improvement in neurological status compared with preoperatively; 3) disc height success, that is, no more than a 2-mm reduction in anterior or posterior height; 4) no serious AEs caused by the implant or by the implant and the surgical procedure; and 5) no additional surgery classified as a failure. Compared to that in the control group, improvement in the investigational group was statistically greater according to the ODI and SF-36 Physical Component Summary (PCS) at 1, 2, and 5 years; the NRS for back pain at 1 and 2 years; and the NRS for leg pain at 1 year. The rates of heterotopic ossification increased over time: 1.0% (4/382) at 1 year, 2.6% (9/345) at 2 years, and 5.9% (11/187) at 5 years. Investigational patients had fewer device-related AEs and serious device-related AEs than the control patients at both 2 and 5 years postoperatively. Noninferiority of the composite measure overall success was demonstrated at all follow-up intervals; superiority was demonstrated at 1 and 2 years. Lumbar disc arthroplasty is a safe and effective treatment for single-level lumbar degenerative disc disease, resulting in improved physical function and reduced pain up to 5 years after surgery.Clinical trial registration no.: NCT00635843 (clinicaltrials.gov).

116. Comparison of imputation methods for evaluating long-term clinical outcomes following lumbar total disc replacement

BACKGROUND CONTEXT The problem of missing data is common in clinical trials, and it can have a significant impact on the conclusions that can be drawn from the data. Long-term results are particularly susceptible as the lost to follow-up (LTFU) rates increase over the course of a trial. Imputation methods are often used to account for missing data points, but some may either under or overestimate the true treatment effect. PURPOSE In this post-hoc analysis of a randomized clinical trial, we evaluated the clinical success of three motion preserving artificial discs up to 7 years following lumbar total disc replacement (TDR) using different imputation methods. STUDY DESIGN/SETTING Randomized, controlled, multicenter clinical IDE trial. PATIENT SAMPLE A total of 324 subjects with single level degenerative disc disease and discogenic pain. OUTCOME MEASURES Radigraphic range of motion on flexion-extension, Oswestry Disability Index (ODI), neurologic exam, adverse events, subsequent surgery. METHODS Subjects were randomized to receive either a semi-constrained mobile core disc (n=218) or a control device (n=106) which was either a constrained (n=65) or unconstrained (n=41) core disc. Several imputation methods were used to calculate clinical success, including: missing values=failure, missing values=success, last observation carried forward (LOCF), complete case, best case and worst case scenarios. Clinical success scores were compared between the treatment (semi-constrained) and control (constrained or unconstrained) groups.Clinical outcomes were collected from baseline through to 7 years following single level (L4-L5 or L5-S1) TDR. Clinical success was defined as a ≥15 point improvement in ODI from baseline, maintenance or improvement in ROM and neurological evaluation (motor and sensory), the absence of index-level subsequent surgical interventions (SSI) and serious device-related adverse events (SDAE). RESULTS By imputing missing values as failures, individual success scores decreased at 5 and 7 years compared to 2 years postop for both groups. Only ROM success at 2 years was significantly greater in the treatment compared to control group (58.7% vs 42.5%, p=0.0065). The overall success score, which is a composite of the individual success scores, also decreased over time, but it was significantly greater in the treatment group at 2 years (42.2% vs 28.3%, p=0.0020). Using complete case data, clinical success at 5 and 7 years was maintained close to 2-year values for overall and individual success scores, except for SDAE success which decreased at 7 years from 2 years for both the treatment (86.1% to 67.1%) and control groups (78.7% to 63.2%). Similarly, LOCF clinical outcomes were the same between 5 and 7 years postop for both groups. By imputing missing values as successes, the results were comparable to scores yielded by complete case and LOCF imputation methods. CONCLUSIONS The missing=failure imputation method is most susceptible to LFTU and may underestimate the treatment effect if there is a large LTFU rate, which is inherent in most long-term clinical studies. Complete case and LOCF imputation methods may be more accurate estimates of long-term clinical outcomes for clinical studies with a large patient enrollment. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

217. Impact of previous lumbar spine surgery on outcome of lumbar total disc replacement: analysis of prospective five-year follow up study data

BACKGROUND CONTEXT FDA-regulated prospective trials evaluating lumbar total disc replacement (LTDR) have included patients with previous lumbar surgeries. Unitedhealth care, one of the largest insurers in the United States recently issued a positive coverage policy for LTDR that disqualifies patients with previous lumbar surgeries of any kind from treatment with LTDR. However, such patients were included in FDA IDE trials that led to approval of these devices. PURPOSE The purpose of this study was to compare LTDR outcomes in patients with prior lumbar spine surgery to outcomes in those without prior surgery. STUDY DESIGN/SETTING The study was a post hoc analysis of data collected prospectively as part of an FDA-regulated trial with 5-year follow-up. PATIENT SAMPLE The study was based on 376 patients from the activL® IDE study population. All patients were treated for single-level symptomatic degenerative disc disease at L4-L5 or L5-S1 unresponsive to at least 6 months of nonoperative care. OUTCOME MEASURES Clinical outcome measures used in the study included Oswestry Disability Index (ODI), Visual analog scales (VAS) assessing back and leg pain, SF-36, adverse events and reoperations. Radiographic outcome evaluations were based on flexion/extension range of motion (ROM) and translation of the operated segment. METHODS Patients were divided into two groups: prior lumbar surgery (PLS, n=92) and no prior lumbar surgery (NPLS, n=284). PLS patients had undergone one or more of the following procedures: intradiscal electrothermal annuloplasty (IDET) (n=5), percutaneous nucleoplasty (n=4), microdiscectomy (n=81), hemilaminectomy (n=17), laminotomy (n=36) or other (n=1) prior to receiving a LTDR. Patients with prior lumbar fusion were excluded from the IDE study. Baseline characteristics, functional and pain outcomes, serious adverse events and reoperations were statistically compared between the groups preoperatively and postoperatively at 6 weeks, 3 and 6 months and 1, 2, 3, 4 and 5 years. RESULTS Patient baseline demographics were very similar between the two groups. When comparing pre- to postoperative scores, ODI, VAS back pain and leg pain and the SF-36 Physical Component Score improved significantly (p CONCLUSIONS Prior lumbar spine surgery was not related to compromised outcomes among patients undergoing LTDR. There were no statistically significant differences in ODI, SF-36, pain scores or safety rates between PLS and NPLS patients. These results are in line with findings from earlier studies that prior surgery is not a contraindication for LTDR provided that other selection criteria are met. These results do not support the denial by an insurer to give patients and providers the option of receiving LTDR for DDD unresponsive to nonoperative care as described in the FDA approved device usage labeling. FDA DEVICE/DRUG STATUS activL (Approved for this indication), ProDisc-L (Approved for this indication), Charite (Approved for this indication)

250. Interspinous process distraction compared to nonoperative care for moderate lumbar degenerative disc disease: results of the FDA IDE clinical trial

BACKGROUND CONTEXT Interspinous process distraction (IPD) devices aim to alleviate back and leg pain by limiting extension and unloading the 3-joint complex at the affected lumbar level. IPDs may offer a treatment option for painful degenerative disc disease (DDD) that is not yet indicated for fusion or disc replacement. PURPOSE To compare the safety and effectiveness of IPD and nonoperative treatment after 2 years for the treatment of moderate lumbar DDD. STUDY DESIGN/SETTING A prospective, randomized, controlled FDA IDE clinical trial at 23 US centers (ClinicalTrials.gov: NCT00456378). PATIENT SAMPLE A total of 278 patients with moderate low back pain for less than 1 year and radiographic evidence of single-level DDD between L2 and L5 who failed at least 6 weeks but less than 6 months of conservative management were randomized and treated with investigational IPD (n=181) or control nonoperative treatment (n=97). OUTCOME MEASURES The primary endpoint was Overall Success, a composite variable that included: 1) Oswestry Disability Index (ODI) score improvement of ≥ 15 points; and 2) no serious adverse event (AE) caused by the implant or by both the implant and surgical procedure (IPD) or caused by the nonoperative treatment (control); and 3) no secondary surgery (IPD) or treatment surgery (control) at the involved level. Additional safety and effectiveness endpoints included back and leg pain numerical (0-20) rating scales, SF-36 PCS/MCS, AEs and secondary surgeries. METHODS Investigational treatment consisted of the IPD implantation (without decompression) and nonoperative treatments, as necessary. Control treatment consisted of information/ education on low back pain, medication, physical therapy, and epidural and/or facet joint steroidal injections. Clinical and radiographic assessments were performed preoperatively, intra-operatively, and postoperatively up to 2 years. Statistical analyses used Bayesian methods with non-informative priors. Last observation was carried forward (LOCF) for patients lost to follow-up including patients receiving surgery (control crossovers) or additional surgery (IPD investigational) at the involved level. RESULTS Baseline demographic characteristics and outcomes scores were not statistically different between the two groups, except back pain (16.8 for investigational vs 16.1 for control, p=0.033). The IPD rate of Overall Success at 24-months was statistically superior to control (observed rate of 63.0% vs 13.4%, respectively; posterior probability of superiority (pps) > 99.9%). The improvement in outcomes for IPD was statistically superior to control (pps > 99.9%) for: ODI (26.4 vs 1.1), back pain (8.4 vs 1.2), leg pain (4.9 vs -1.1, PCS (12.6 vs.1.4), and MCS (4.4 vs -0.8). Spinous process bony erosion increased slowly to 33.7% (61/181) of patients but was not related to clinical outcomes. Treatment-related serious AEs in the control group were associated with increasing low back pain. Fifteen (8.3%) IPD and 34 (35.1%) control patients experienced a treatment-related serious AE. Twenty (11.0%) IPD patients had secondary surgery and 10 (10.3%) control patients had treatment surgery at the index level. After 6 months of nonoperative treatment, control patients had the option to crossover to IPD: 57 (58.8%) control patients had crossed over by 24 months. CONCLUSIONS These analyses support the superiority of this IPD over conservative care for moderate back pain in appropriately selected patients. FDA DEVICE/DRUG STATUS DIAM™ Spinal Stabilization System (Investigational/Not approved)

Symptomatic Adjacent Segment Disease After Anterior Cervical Discectomy for Single-level Degenerative Disk Disease

A prospective cohort of 142 patients underwent either anterior cervical discectomy alone, anterior cervical discectomy with fusion by cage stand-alone, or anterior cervical discectomy with arthroplasty. We then followed up on their condition for a mean of 9.1±1.9 years (5.6-12.2 y) later. We aimed to evaluate the annual rate of clinically symptomatic adjacent segment disease (ASD) and to analyze predictive factors. Until recent, ASD has been predominantly evaluated radiologically. It is not known whether all patients had complaints. A frequent cited annual rate of ASD is 2.9%, but a growing number of studies report a lower annual rate. Furthermore, maintaining motion to prevent ASD is one reason for implanting a cervical disk prosthesis. However, the results of studies contradict one another. Participants took part in a randomized controlled trial that ended prematurely because of the publication of evidence that did not justify continuation of the trial. The patients were randomly allocated to 3 groups, each of which received one of the abovementioned treatments. We defined symptomatic ASD as signs and symptoms caused by degeneration of an intervertebral disk adjacent to a level of previous anterior cervical disk surgery. At the last follow-up, we were able to ascertain whether clinically symptomatic ASD was present in any of the participants. The overall annual rate of symptomatic ASD was 0.7%. We found no statistically significant correlations between any of the investigated factors and symptomatic ASD except for the surgical method used. Symptomatic ASD was seen less often in anterior cervical discectomy solely or anterior cervical discectomy with arthroplasty than in anterior cervical discectomy with fusion by plate fixation. The annual rate of symptomatic ASD after an anterior cervical discectomy procedure was estimated to be 0.7%. This seems to be related to the procedure, although firm conclusions cannot be drawn. Level 2-prospective cohort.

Comparison of Lumbar Total Disc Replacement With Surgical Spinal Fusion for the Treatment of Single-Level Degenerative Disc Disease: A Meta-Analysis of 5-Year Outcomes From Randomized Controlled Trials.

Study Design:Meta-analysis.Objectives:To evaluate the long-term efficacy and safety of total disc replacement (TDR) compared with fusion in patients with functionally disabling chronic low back pain due to single-level lumbar degenerative disc disease (DDD) at 5 years.Methods:PubMed and Cochrane Central Register of Controlled Trials databases were searched for randomized controlled trials reporting outcomes at 5 years for TDR compared with fusion in patients with single-level lumbar DDD. Outcomes included Oswestry Disability Index (ODI) success, back pain scores, reoperations, and patient satisfaction. All analyses were conducted using a random-effects model; analyses were reported as relative risk (RR) ratios and mean differences (MDs). Sensitivity analyses were conducted for different outcome definitions, high loss to follow-up, and high heterogeneity.Results:The meta-analysis included 4 studies. TDR patients had a significantly greater likelihood of ODI success (RR 1.0912; 95% CI 1.0004, 1.1903) and patient satisfaction (RR 1.13; 95% CI 1.03, 1.24) and a significantly lower risk of reoperation (RR 0.52; 95% CI 0.35, 0.77) than fusion patients. There was no association with improvement in back pain scores whether patients received TDR or fusion (MD −2.79; 95% CI −8.09, 2.51). Most results were robust to sensitivity analyses. Results for ODI success and patient satisfaction were sensitive to different outcome definitions but remained in favor of TDR.Conclusions:TDR is an effective alternative to fusion for lumbar DDD. It offers several clinical advantages over the longer term that can benefit the patient and reduce health care burden, without additional safety consequences.

34 - Five-Year Results of a Randomized Controlled Trial for Lumbar Artificial Discs in Single-Level Degenerative Disc Disease

BACKGROUND CONTEXT: The activL artificial disc received Food and Drug Administration approval in 2015 based on 2-year follow-up data. Long-term outcomes with this lumbar total disc replacement have not been reported to date.

32 - Comparison of Lumbar Total Disc Replacement with Spinal Fusion for the Treatment of Single-Level Degenerative Disc Disease: a Meta-Analysis of 5-year Outcomes from Randomized Controlled Trials

32 - Comparison of Lumbar Total Disc Replacement with Spinal Fusion for the Treatment of Single-Level Degenerative Disc Disease: a Meta-Analysis of 5-year Outcomes from Randomized Controlled Trials

Cervical sagittal alignment after different anterior discectomy procedures for single-level cervical degenerative disc disease: randomized controlled trial

BackgroundThe effect of anterior cervical discectomy without fusion (ACD), ACD with fusion by stand-alone cage (ACDF) or with arthroplasty (ACDA) on cervical sagittal alignment is not known and is the subject of this study.MethodsA total of 142 adult patients with single-level cervical disease were at random allocated to different procedures: ACD (45), ACDF (47) and ACDA (50). Upright cervical spine radiographs were obtained. Angles of the involved angle and the angle between C2 and C7 were determined.ResultsAfter a mean follow-up of 25.4 ± 18.4 months, the angles of the involved level comparing ACD with ACDA and ACD with ACDF were different, reaching statistical significance. However, the angle between C2 and C7 did not differ between groups or between preoperative values and at follow-up.ConclusionsIrrespective of the technique used for anterior cervical discectomy for single-level degenerative disc disease, the alignment of the cervical spine is unaltered.