Innovative Biological Treatment Methods for Degenerative Disc Disease.

Low back pain is the leading cause of work absences and years lived with disability, and it is often associated with degenerative disc disease. In recent years, biological treatment approaches such as the use of growth factors, cell injections, annulus fibrosus (AF) repair, nucleus pulposus replacement, and tissue-engineered discs have been explored as means for preventing or reversing degenerative disc disease. Both animal and clinical studies have shown promising results for cell-based therapy on the grounds of its regenerative potential. Clinical data also indicate that stem cell injection is safe when appropriately performed, albeit its long-term safety and efficacy are yet to be explored. Numerous challenges also remain to be overcome, such as isolating, differentiating, and preconditioning the disc cells, as well as managing the nutrient-deficient and oxygen-deficient micromilieu of the intervertebral disc (IVD). AF repair methods including devices used in clinical trials have shown success in decreasing reherniation rates and improving overall clinical outcomes. In addition, recent studies that combined AF repair and nucleus pulposus replacement have shown improved biomechanical stability in IVDs after the combined treatment. Tissue-engineered IVDs for total disc replacement are still being developed, and future studies are necessary to overcome the challenges in their delivery, efficacy, and safety.

Ten-Year Outcomes of 1- and 2-Level Cervical Disc Arthroplasty From the Mobi-C Investigational Device Exemption Clinical Trial.

BACKGROUND: Short- and mid-term studies have shown the effectiveness of cervical disc arthroplasty (CDA) to treat cervical disc degeneration. OBJECTIVE: To report the 10-yr outcomes of a multicenter experience with cervical arthroplasty for 1- and 2-level pathology. METHODS: This was a prospective study of patients treated with CDA at 1 or 2 contiguous levels using the Mobi-C® Cervical Disc (Zimmer Biomet). Following completion of the 7-yr Food and Drug Administration postapproval study, follow-up continued to 10 yr for consenting patients at 9 high-enrolling centers. Clinical and radiographic endpoints were collected out to 10 yr. RESULTS: At 10 yr, patients continued to have significant improvement over baseline Neck Disability Index (NDI), neck and arm pain, neurologic function, and segmental range of motion (ROM). NDI and pain outcomes at 10 yr were significantly improved from 7 yr. Segmental and global ROM and sagittal alignment also were maintained from 7 to 10 yr. Clinically relevant adjacent segment pathology was not significantly different between 7 and 10 yr. The incidence of motion restricting heterotopic ossification at 10 yr was not significantly different from 7 yr for 1-level (30.7% vs 29.6%) or 2-level (41.7% vs 39.2%) patients. Only 2 subsequent surgeries were reported after 7 yr. CONCLUSION: Our results through 10 yr were comparable to 7-yr outcomes, demonstrating that CDA with Mobi-C continues to be a safe and effective surgical treatment for patients with 1- or 2-level cervical degenerative disc disease.

Clinical and radiological outcomes of single-level cervical disc arthroplasty in the patients with preoperative reversible kyphosis: A matched cohort study.

OBJECTIVE: The performance of cervical disc arthroplasty (CDA) in the spine with malalignment was unclear. The purpose of the study was to report the clinical and radiological outcomes of single-level CDA in the patients with preoperative reversible kyphosis (RK) and compare these results with a matched cohort of preoperative lordosis. PATIENTS AND METHODS: From 2014 to 2018, 36 patients with preoperative RK were matched with 229 patients with preoperative lordosis. The Japanese Orthopedic Association score, Neck Disability Index, Visual Analog Scale were used to evaluate clinical outcomes. Radiological evaluations included range of motion (ROM), C2-7 Cobb angle, shell angle (SA) at surgical level, functional spinal unit (FSU) angle and heterotopic ossification (HO). RESULTS: The mean follow-up was 40.1 months. Both groups achieved significant improvements in clinical outcomes without significant intergroup differences. Before surgery, lordosis group had significantly greater C2-7 angle (9.5° vs -8.4°), SA (1.6° vs -3.7°), and FSU (2.9° vs -3.7°). After surgery, RK group experienced significant improvements in C2-7 angle and SA compared with preoperative data. In lordosis group, C2-7 angle, SA, and FSU were maintained. At the last follow-up, the intergroup difference of C2-7 angle, SA, and FSU remained significant. ROMs were preserved in both groups. The ROM of RK group was slightly lower than that of lordosis group but failing to reach a significance. Eleven patients in lordosis group and 21 patients in RK group developed HO (P = 0.127). There was a significant greater incidence of high-grade HO (grade Ⅲ, Ⅳ) in RK group (33.3 % vs 11.1 %, P = 0.034). CONCLUSION: Both groups achieved satisfactory and comparable clinical outcomes after CDA. Despite the remarkable improvements compared with preoperative values, the cervical alignment of RK group was still significantly inferior to that of lordosis group. More HO formation occurred in RK group. Based on these results, we did not recommend CDA to the patients with preoperative RK.

Facet Arthropathy Following Disc Replacement Versus Rehabilitation: A Prospective Study With 8-Year Follow-Up.

STUDY DESIGN: A prospective study of patients originally randomized to total disc replacement (TDR) or multidisciplinary rehabilitation. OBJECTIVE: To assess the long-term development of facet arthropathy (FA) after TDR versus nonoperative treatment, and to analyze the association between FA and clinical outcome. SUMMARY OF BACKGROUND DATA: FA may appear or increase following TDR, but the natural course of FA is unclear, and no previous study has evaluated the long-term development of FA following TDR compared with nonoperative treatment. METHODS: The study included 126 patients with chronic low back pain and degenerative changes in the lumbar intervertebral discs. The patients underwent pretreatment and 8-year follow-up magnetic resonance imaging (MRI) and 8-year follow-up computed tomography (CT) of the lumbar spine. The primary outcome measure was FA development (yes/no) on MRI at index level L4/L5 or L5/S1, defined as increased FA grade value from pretreatment to follow-up according to Weishaupt grading system. Secondary outcomes included the association between FA (on MRI and CT) and Oswestry Disability Index (ODI) or back pain as well as reoperations. RESULTS: Increased index level FA grade was more frequent after TDR versus nonoperative treatment (36%, 25/69 vs. 2%, 1/57 of patients, P < 0.001), but was not related to change in ODI or back pain. At follow-up, index level FA grades were higher after TDR versus nonoperative treatment (odds ratio 4.0 MRI and 5.9 CT), but were not related to ODI less than or equal to 22. Four patients (6%) treated with TDR and no patients treated nonoperatively were operated for lateral recess stenosis with posterior decompression at the index level during follow-up. CONCLUSION: Index level FA development was more likely after TDR compared with nonoperative treatment but was not associated with the 8-year clinical outcome. Index level FA may have contributed to reoperations in the TDR group. LEVEL OF EVIDENCE: 2.

Lumbar spine surgery across 15 years: trends, complications and reoperations in a longitudinal observational study from Norway.

BACKGROUND: Studies from different Western countries have reported a rapid increase in spinal surgery rates, an increase that exceeds by far the growing incidence rates of spinal disorders in the general population. There are few studies covering all lumbar spine surgery and no previous studies from Norway. OBJECTIVES: The purpose of this study was to investigate trends in all lumbar spine surgery in Norway over 15 years, including length of hospital stay, and rates of complications and reoperations. DESIGN: A longitudinal observational study over 15 years using hospital patient administrative data and sociodemographic data from the National Registry in Norway. SETTING AND PARTICIPANTS: Patients aged ≥18 years discharged from Norwegian public hospitals between 1999 and 2013. OUTCOME MEASURES: Annual rates of simple (microsurgical discectomy, decompression) and complex surgical procedures (fusion, disc prosthesis) in the lumbar spine. RESULTS: The rate of lumbar spine surgery increased by 54%, from 78 (95% CI (75 to 80)) to 120 (107 to 113) per 100 000, from 1999 to 2013. More men had simple surgery whereas more women had complex surgery. Among elderly people over 75 years, lumbar surgery increased by a factor of five during the 15-year period. The rates of complications were low, but increased from 0.7% in 1999 to 2.4% in 2013. CONCLUSIONS: There was a substantial increase in lumbar spine surgery in Norway from 1999 to 2013, similar to trends in other Western world countries. The rise in lumbar surgery among elderly people represents a significant workload and challenge for health services, given our aging population.

Clinical and Radiographic Outcome of Patients With Cervical Spondylotic Myelopathy Undergoing Total Disc Replacement.

STUDY DESIGN: A nonrandomized, prospective, and single-center clinical trial. OBJECTIVE: The aim of this study was to investigate the clinical and radiographic efficacy of ProDisc Vivo cervical total disc replacement (cTDR) in patients with clinical and radiographic documented cervical spondylotic myelopathy (CSM), due to degenerative changes at the index level. SUMMARY OF BACKGROUND DATA: Decompression and fusion is still the gold standard in patients with cervical myelopathy. Very limited data are available regarding the application of cTDR in patients with clinical and radiological documented CSM in context of clinical and radiographic outcomes. METHODS: Clinical outcome scores included the Neck Disability Index (NDI), Visual Analogue Scale (VAS), arm and neck pain self-assessment questionnaires as well as the Nurick grade and the Japanese Orthopaedic Association (JOA) score. The radiological outcome included the range of motion (ROM), the segmental and global (C2-C7) lordosis, and the occurrence of heterotopic ossifications. RESULTS: Eighteen consecutive patients (10 males, 8 females) with documented clinical and radiological signs of myelopathy were included in this investigation. The study population had a mean age of 52.4 years and a follow-up period of 20.3 months in average (range 3-48 months). The mean range ROM of the index level stayed consistent with 6.8° preoperatively and 7.2° (P = 0.578) at the last follow-up; the global lordosis in neutral position changed from 3.5° to 14.2° significantly (P = 0.005) in mean. The JOA score improved from 11.3 to 16.6 (P < 0.001) as well as the NDI 36.7 to 10.3 (P < 0.001) and the VAS score from 5.7/6.1 (arm/neck) to 1.3/2.0 (P < 0.001/P < 0.001). The mean Nurick grade was 1.33 preoperatively and dropped down in all cases to Nurick grade of 0 (P < 0.001). CONCLUSION: cTDR (with ProDisc Vivio) in patients with CSM yielded good clinical and radiographic outcomes and found as a reliable, safe, and motion-preserving surgical treatment option, although its indication is very limited due to numerous exclusion criteria. LEVEL OF EVIDENCE: 4.

Radiological exploration on adjacent segments after total cervical disc replacement with Prodisc-C prosthesis.

PURPOSE: The relationship between upper or lower adjacent segments (UAS/LAS) and the cervical spine parameters was not clear yet. So, the purpose was to analyze range of motion (ROM), lordosis (LOR), and intervertebral disc height (IDH) of UAS and LAS before and after total cervical disc replacement (TDR) and to explore the influencing factors of cervical spine radiological parameters on adjacent segments. METHODS: A single-center retrospective study was performed on patients completing 10-year follow-up undergone TDR. As the primary outcomes, radiological parameters included UAS-ROM/LAS-ROM, UAS-LOR/LAS-LOR, and UAS-IDH/LAS-IDH. The secondary outcomes were ROM and LOR of C2-C7 and surgical levels, IDH of surgical segments, prosthesis migration, subsidence, heterotopic ossification (HO), and adjacent segment degeneration (ASD), which were measured on X-ray. RESULTS: UAS-ROM and LAS-ROM remained stable in follow-up periods. There was no significance on UAS-LOR or LAS-LOR between pre- and post- operation, so was UAS-IDH or LAS-IDH. UAS-ROM was larger in the segments with ASD (P < 0.001), the same to LAS-ROM (P < 0.001), and UAS-LOR was larger in segments with ASD (P = 0.02). UAS-ROM was positively correlated with C2-C7 ROM and LOR (both P < 0.001). UAS-LOR was correlated with operated-segmental LOR while LAS-LOR were in correlation with surgical segment ROM. The influencing factors of UAS-ROM were the surgical segment ROM and C2-C7 LOR. The influencing factors of UAS-LOR and LAS-LOR were LAS-ROM and UAS-ROM, respectively. The influencing factors of UAS-IDH were LAS-IDH, surgical segment IDH, and HO while that of LAS-IDH were UAS-IDH and surgical segment IDH. CONCLUSIONS: TDR has only a little effect on the adjacent segments. There is an interaction between UAS and LAS. The maintenance on surgical segments ROM and reconstruction of IDH will benefit to adjacent segments.

Outpatient and Inpatient Single-level Cervical Total Disc Replacement: A Comparison of 30-day Outcomes.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The aim of this study was to compare 30-day postoperative outcomes between patients undergoing outpatient and inpatient single-level cervical total disc replacement (TDR) surgery. SUMMARY OF BACKGROUND DATA: Cervical TDR is a motion-sparing treatment for cervical radiculopathy and myelopathy. It is an alternative to anterior cervical discectomy and fusion (ACDF) with a similar complication rate. Like ACDF, it may be performed in the inpatient or outpatient setting. Efforts to reduce health care costs are driving spine surgery to be performed in the outpatient setting. As cervical TDR surgery continues to gain popularity, the safety of treating patients on an outpatient basis needs to be validated. METHODS: The National Surgical Quality Improvement Program (NSQIP) database was queried for patients who underwent single-level cervical disc replacement surgery between 2006 and 2015. Complication data including 30-day complications, reoperation rate, readmission rate, and length of stay data were compared between the inpatient and outpatient cohort using univariate analysis. RESULTS: There were 531 (34.2%) patients treated as outpatients and 1022 (65.8%) were treated on an inpatient basis. The two groups had similar baseline characteristics. The overall 30-day complication rate was 1.4% for inpatients and 0.6% for outpatients. Reoperation rate was 0.6% for inpatient and 0.4% for outpatients. Readmission rate was 0.9% and 0.8% for inpatient and outpatient, respectively. There were no statistical differences identified in rates of readmission, reoperation, or complication between the inpatient and outpatient cohorts. CONCLUSION: There was no difference between 30-day complications, readmission, and reoperation rates between inpatients and outpatients who underwent a single-level cervical TDR. Furthermore, the overall 30-day complication rates were low. This study supports that single-level cervical TDR can be performed safely in an outpatient setting. LEVEL OF EVIDENCE: 3.

Adjacent segment degeneration or disease after cervical total disc replacement: a meta-analysis of randomized controlled trials.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) has been widely used in cervical spondylosis, but adjacent segment degeneration/disease (ASD) was inevitable. Cervical total disc replacement (TDR) could reduce the stress of adjacent segments and retard ASD in theory, but the superiority has not been determined yet. This analysis aimed that whether TDR was superior to ACDF for decreasing adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDis). METHODS: A meta-analysis was performed according to the guidelines of the Cochrane Collaboration with PubMed, EMBASE, Cochrane Library and CBM (China Biological Medicine) databases. It included randomized controlled trials (RCTs) that reported ASDeg, ASDis, and reoperation on adjacent segments after TDR and ACDF. Two investigators independently selected trials, assessed methodological quality, and evaluated the quality of this meta-analysis using the grades of recommendation, assessment, development, and evaluation (GRADE) approach. RESULTS: Eleven studies with 2632 patients were included in the meta-analysis. The overall rate of ASD in TDR group was lower than ACDF group (OR = 0.6; 95% CI [0.38, 0.73]; P < 0.00001). Both the incidence of ASDeg and the reoperation rate were statistically lower in the TDR group than in the ACDF group (OR = 0.58, P < 0.00001; OR = 0.52, P = 0.01, respectively). Subgroup analysis was performed according to the follow-up time and trial site; the rate of ASDeg was lower in patients underwent TDR no matter the follow-up time, and TDR tended to increase the superiority across time. The rate of ASDeg was also lower with TDR both in the USA and China (P < 0.0001, P = 0.03, respectively). But the cost-effectiveness result might be prone to neither of the two surgery approaches. According to GRADE, the overall quality of this meta-analysis was moderate. CONCLUSIONS: TDR decreased the rates of ASDeg and reoperation compared with that of ACDF, and the superiority may become more apparent over time. We cautiously and slightly suggest adopting TDR according to the GRADE but may not believe it excessively.

Transforaminal Endoscopic Decompression for Foot Drop 12 Years After Lumbar Total Disk Replacement.

Lumbar total disk replacement is considered for the treatment of lumbar degenerative disk disease with the hope that by preserving motion, the long-term fusion complication of adjacent segment disease can be avoided. The complications of lumbar total disk replacement can be divided into approach-related and long-term complications. Little has been described about the complications and treatment for complications >10 years after the device has been implanted. Here we describe a transforaminal endoscopic diskectomy procedure for a patient presenting with foot drop 12 years after a L5-S1 total disk replacement.

Intraoperative Anterior Migration of the Prestige-LP Cervical Disc Owing to an Inappropriate Implantation Sequence During Continuous 2-Level Artificial Cervical Disc Replacement: A Case Report with 8-Year Follow-Up.

BACKGROUND: Owing to its unique advantages, 2-level artificial cervical disc replacement (ACDR) is gaining attention. Among artificial discs designed for use in ACDR, the Food and Drug Administration-approved Prestige-LP Cervical Disc is widely used. There are no standard implantation sequences for 2-level ACDR using the Prestige-LP disc, and complications resulting from inappropriate implantation sequences remain unknown. CASE DESCRIPTION: A 45-year-old woman underwent continuous 2-level ACDR using the Prestige-LP disc and experienced anterior migration of a previously inserted artificial disc after secondary disc implantation at an upper segment owing to an inappropriate implantation sequence during surgery. Intraoperative radiographs showed stable index levels and artificial discs. We tapped the migrated disc back into its correct position and recommended a postoperative functional exercise plan to the patient. We followed the patient for 8 years to verify the safety of our solution. We developed an implantation strategy for 2-level ACDR to avoid this complication in the future. CONCLUSIONS: During 2-level ACDR, a top-down sequence should be used to implant prostheses. When anterior disc migration occurs, intraoperative radiographs should be obtained to ensure stability of the index levels. If there is no instability, the migrated tab can be tapped back into its correct position. In addition, limiting motion rather than allowing intermittent movement of the neck for at least 3 months is important to promote union between bone and prosthesis.

The Seven-Year Cost-Effectiveness of Anterior Cervical Discectomy and Fusion Versus Cervical Disc Arthroplasty: A Markov Analysis.

STUDY DESIGN: Markov model analysis. OBJECTIVE: The aim of this study was to determine the 7-year cost-effectiveness of single-level anterior cervical discectomy and fusion (ACDF) versus cervical disc replacement (CDR) for the treatment of cervical disc degeneration. SUMMARY OF BACKGROUND DATA: Both ACDF and CDR are acceptable surgical options for the treatment of symptomatic cervical disc degeneration. Past studies have demonstrated at least equal effectiveness of CDR when compared with ACDF in large randomized Investigational Device Exemption (IDE) studies. Short-term cost-effectiveness analyses at 5 years have suggested that CDR may be the preferred treatment option. However, adjacent segment disease and other postoperative complications may occur after 5 years following surgery. METHODS: A Markov model analysis was used to evaluate data from the LDR Mobi-C IDE study, incorporating five Markov transition states and seven cycles with each cycle set to a length of 1 year. Transition state probabilities were determined from complication rates, as well as index and adjacent segment reoperation rates from the IDE study. Raw SF-12 data were converted to health state utility values using the SF-6D algorithm for 174 CDR patients and 79 ACDF patients. RESULTS: Assuming an ideal operative candidate who is 40-years-old and failed appropriate conservative care, the 7-year cost was $103,924 for ACDF and $105,637 for CDR. CDR resulted in the generation of 5.33 quality-adjusted life-years (QALYs), while ACDF generated 5.16 QALYs. Both ACDF and CDR were cost-effective, but the incremental cost-effectiveness ratio (ICER) was $10,076/QALY in favor of CDR, which was less than the willingness-to-pay (WTP) threshold of $50,000/QALY. CONCLUSION: ACDF and CDR are both cost-effective strategies for the treatment of cervical disc degeneration. However, CDR is the more cost-effective procedure at 7 years following surgery. Further long-term studies are needed to validate the findings of this model. LEVEL OF EVIDENCE: 1.

Influence of the Initial Sagittal Lumbar Alignment on Clinical and Radiological Outcomes of Single-Level Lumbar Total Disc Replacements at a Minimum 2-Year Follow-up.

STUDY DESIGN: Retrospective cohort study OBJECTIVE.: To analyze the clinical and radiographic outcomes of patients undergoing a one-level lumbar total disc replacement (TDR), according to the initial sagittal alignment of the spine. SUMMARY OF BACKGROUND DATA: No authors have highlighted correlation between the initial spinopelvic parameters and the postoperative outcome after a one-level TDR. METHODS: Seventy-eight patients were included: 14 TDR at L4-L5 and 64 TDR at L5-S1 level. Clinical assessment was performed on leg pain and axial back pain Visual Analog Scale (VAS), Oswestry Disability Index, and Short Form-36 Health Survey. Radiographic assessment included full spine standing anteroposterior and lateral films. Data were compared according to the initial lumbar sagittal alignment described by Roussouly. RESULTS: Forty-five female patients and 33 male patients with a mean age of 41.7 years (95% confidence interval [40.3-43.1]) were included. The mean follow-up was 46.4 months (95% [40.6-51.6]). Two patients were considered as Roussouly type 1 (2.6%), 36 patients as type 2 (46.2%), 33 patients as type 3 (42.3%), and 7 patients as type 4 (9%). Preoperatively, there were no clinical differences depending on Roussouly's type of back. Pelvic incidence (P < 0.001), sacral slope (P < 0.001), lumbar lordosis (P < 0.001), and spinosacral angle (P < 0.001) were different between the Roussouly's types of back. Postoperative clinical outcome improved (P < 0.001) but did not vary according to the Roussouly types except for leg pain VAS (P = 0.03). Post hoc tests did not reveal difference between the Roussouly's types and leg pain VAS. Postoperative radiographic outcomes did not change excepted for the lumbar lordosis (P < 0.001), thoracic kyphosis (P = 0.007), and spinosacral angle (P = 0.02). The Roussouly type had no effect on the postoperative course of radiographic parameters. CONCLUSION: Equivalent clinical and radiographic outcomes have been highlighted independently of the increasing of the sacral slope for patients with one-level lumbar TDR. LEVEL OF EVIDENCE: 3.

Foreword: Proceedings From the First Annual Lumbar Total Disc Replacement Summit.

: This publication focuses on proceedings from the First Annual Lumbar Total Disc Replacement Summit, held October 25, 2016 in Boston, MA. The Summit brought together 17 thought leading surgeons who employed a modified-Delphi method to determine where consensus existed pertaining to the utilization of lumbar total disc replacement as a standard of care for a subpopulation of patients suffering from degenerative disc disease.

Process for Consensus Statements on Lumbar Total Disc Replacement.

: Consensus statements regarding the evidence-base for lumbar total disc replacement, as it pertains to payer decision-making, were developed through a modified-Delphi technique involving 17 spine surgeons and a former payer medical director. The Delphi process involved one round of anonymous survey and one round with a face-to-face meeting. The survey was a 51-item, electronically administered questionnaire to determine level of agreement with proposed statements on the evidence for lumbar total disc replacement and to provide additional diagnosis and management practice information for further deliberations. A subset of the proposed statements was discussed at the face-to-face meeting to identify reasons for disagreement, revise wording, and obtain consensus. The meeting involved presentation of the current evidence base for lumbar total disc replacement, as well as three themed sessions that were moderated by surgeons on the panel. The voting processes during meeting deliberations remained anonymous. Consensus was defined as ≥ 90% agreement. Consensus was reached on 11 statements, divided into themes that focused on patient eligibility and diagnosis, evidence criteria for coverage decisions, clinical evidence, and budgetary implications.

Barriers to and Budget Impact of Lumbar Total Disc Replacement Utilization.

: Evidence on the favorable efficacy, safety, and cost effectiveness of lumbar total disc replacement (TDR) compared with fusion for lumbar degenerative disc disease is mounting; however, a key barrier identified for TDR utilization is lack of coverage by US health insurers. Although economic considerations in a fee-for-service model should not be a determining factor in patient access, concerns regarding the budget impact of lumbar TDR surgery may unfortunately underlie coverage decisions. On the basis of the data available and economic modeling, the panel agreed that there is no indication that there would be a dramatic increase in patients seeking lumbar TDR. Considering several possible scenarios on potential growth in TDR utilization with coverage, as well as growth in the overall surgical pool of patients, economic modeling demonstrated that adoption of lumbar TDR would result in minimal or no budget impact for commercial insurance plans. Considering these model results and the economic literature, the panel concluded that adopting lumbar TDR within a coverage policy is expected to remain cost neutral for the insurer.

Trends in the Treatment of Single and Multilevel Cervical Stenosis: A Review of the American Board of Orthopaedic Surgery Database.

BACKGROUND: In order to identify any changes in the utilization of new and old techniques, we investigated trends in the operative management of cervical stenosis by orthopaedic surgeons applying for board certification. METHODS: We queried the American Board of Orthopaedic Surgery database from 1998 to 2013 to identify all of the cervical spine procedures for stenosis that had been performed by candidates taking Part II of the licensing examination. Longitudinal trends were determined for the utilized approach, the individual procedures that had been performed, and whether a motion-preserving technique had been employed. RESULTS: There were 5,068 cervical spine procedures performed by 1,025 candidates. Procedure totals remained relatively constant until 2011, when a sudden increase of 280% (202 to 768 procedures) was noted. This trend continued, reaching a 460% increase (202 to 1,131 procedures) compared with 2010. The number of candidates only rose by 150% (42 to 105) over the entire study period. The proportion of procedures performed via an anterior approach saw a bimodal distribution; early on, this approach predominated over posterior procedures and was largely driven by the number of corpectomies that were performed. From 2004 to 2011, posterior procedures became more prevalent, but there was a sharp decline in 2011, driven by the large number of anterior cervical discectomies and fusions that were performed. This remained constant through 2013. Lastly, motion-preserving techniques, which included total disc replacement and laminoplasty, had modest increases in utilization from 2005 to 2007. This increased prevalence was short-lived, and it steadily declined through 2014 to <5% utilization. CONCLUSIONS: The number of candidates performing cervical spine procedures increased more than twofold over a 16-year period. This reflects a larger proportion of the orthopaedic graduates who subspecialize in spine surgery. While the number of surgeons performing spine surgery has increased, the sheer number of procedures that each surgeon performed greatly outpaced the increased number of surgeons. Motion-preserving techniques had their peak utilization in 2007, and have since decreased to <5%, in contrast to fusion techniques, which predominate, comprising >90% of the performed procedures.

Patient-reported Outcomes and Revision Rates at a Mean Follow-up of 10 Years After Lumbar Total Disc Replacement.

STUDY DESIGN: Prospective observational cohort study. OBJECTIVE: The aim of this study was to determine the long-term clinical results and prosthesis survival in patients treated with lumbar total disc replacement (TDR). SUMMARY OF BACKGROUND DATA: Fusion has become the current standard surgical treatment for lumbar degenerative disease. TDR is an alternative treatment that seeks to avoid fusion-related adverse events, specifically adjacent segment disease. METHODS: Sixty-eight consecutive patients treated with TDR from 2003 to 2008 were invited to follow-up and complete a Visual Analog Scale (VAS) for back and leg pain, the Dallas Pain Questionnaire (DPQ), and the Short Form-36. These surveys were also administered to the subjects before their index TDRs. Data on reoperation were collected from the patients' medical records. RESULTS: Fifty-seven (84%) patients were available for follow-up at a mean 10.6 years post-operatively (range 8.1-12.6 years). There was a significant improvement from preop to latest follow-up in VAS (6.8 vs. 3.2, P < 0.000) and DPQ (63.2 vs. 45.6, P = 0.000) in the entire cohort. Nineteen patients (33%) had a revision fusion surgery after their index TDR. Patients who had revision surgery had statistically significant worse outcome scores at last follow-up than patients who had no revision. Thirty patients (52.6%) would choose the same treatment again if they were faced with the same problem. CONCLUSION: This study demonstrated significant improvement in long-term clinical outcomes, similar to previously published studies, and two-thirds of the discus prostheses were still functioning at follow-up. However, there is still a lack of well-designed long-term studies, thus requiring further investigation. LEVEL OF EVIDENCE: 3.

Increased Utilization of Cervical Disk Arthroplasty in University Hospitals with Regional Variation and Socioeconomic Discrepancies.

OBJECTIVE: Treatment of cervical radiculopathy with disk arthroplasty has been approved by the U.S. Food and Drug Administration since 2007. Recently, a significant increase in clinical data including mid- and long-term follow-up has become available, demonstrating the superiority of disk arthroplasty compared with anterior discectomy and fusion. The aim of this project is to assess the nationwide use of cervical disk arthroplasty. METHODS: The University Healthcare Consortium database was accessed for all elective cases of patients treated for cervical radiculopathy caused by disk herniation (International Classification of Diseases [ICD] 722.0) from the fourth quarter of 2012 to the third quarter of 2015. Within this 3-year window, temporal and socioeconomic trends in the use of cervical disk replacement for this diagnosis were assessed. RESULTS: Three thousand four hundred forty-six cases were identified. A minority of cases (10.7%) were treated with disk arthroplasty. Median hospital charges were comparable for cervical disk replacement ($15,606) and anterior cervical fusion ($15,080). However, utilization was seen to increase by nearly 70% during the timeframe assessed. Disk arthroplasty was performed in 8% of patients in 2012 to 2013, compared with 13% of cases in 2015. Disk replacement use was more common for self-paying patients, patients with private insurance, and patients with military-based insurance. There was widespread variation in the use of cervical disk replacement between regions, with a nadir in northeastern states (8%) and a peak in western states (20%). CONCLUSION: Over a short, 3 -year period there has been an increase in the treatment of symptomatic cervical radiculopathy with disk arthroplasty. The authors predict a further increase in cervical disk arthroplasty in upcoming years.