Multilevel Cervical Degenerative Disc Disease Research Articles

Biomechanical Effects on the Prostheses and Vertebrae of Three-Level Hybrid Surgery: A Finite Element Study.

Three-level hybrid surgery (HS) consisting of cervical disc arthroplasty (CDA) and anterior cervical discectomy and fusion (ACDF) has been partly used for the treatment of multi-level cervical degenerative disc disease (CDDD). The complications related to the implants and the collapse of the surgical vertebral bodies had been reported in multi-level anterior cervical spine surgery. Thus, this study aimed to explore the biomechanical effects on the prostheses and vertebrae in three-level HS. A FE model of cervical spine (C0-T1) was constructed. Five surgical models were developed. They were FAF model (ACDF-CDA-ACDF), AFA model (CDA-ACDF-CDA), FFF model (three-level ACDF), SF model (single-level ACDF), and SA model (single-level CDA). A 75-N follower load and 1.0-N·m moment was applied to produce flexion, extension, lateral bending, and axial rotation. Compared with the intact model, the range of motion (ROM) of total cervical spine in FAF model decreased by 34.54%, 54.48%, 31.76%, and 27.14%, respectively, in flexion, extension, lateral bending, and axial rotation, which were lower than those in FFF model and higher than those in AFA model. The ROMs of CDA segments in FAF and AFA models were similar to the intact model and SA model. Compared with the intact model, the ROMs at C3/4 segment in FFF model increased from 5.71% to 7.85%, and increased from 5.31% to 6.81% at C7/T1 segment, following by FAF model, then the FAF model. The maximum interface pressures of the Prestige-LP in FAF model were similar to SA model, however the corresponding values were increased in AFA model. The maximum interface pressures of the Zero-P were increased in FAF and AFA model compared with those in SF and FFF models. The stress was mainly distributed on the screws. In AFA model, the maximum pressures of the ball and trough articulation in superior and inferior Prestige-LP were all increased compared with those in SA and FAF model. In FFF model, the maximum pressures of the vertebrae were higher than those in other models. The stress was mainly distributed on the anterior area of the vertebral bodies. HS seemed to be more suitable than ACDF for the surgical treatment of three-level CDDD in consideration of the biomechanical effects, especially for the two-level CDA and one-level ACDF construct. But a more appropriate CDA prosthesis should be explored in the future.

The Evidence for the Use of Osteobiologics in Hybrid Constructs (Anterior Cervical Discectomy and Fusion and Total Disc Replacement) in Multilevel Cervical Degenerative Disc Disease: A Systematic Review.

Systematic review. Examine the clinical evidence for the use of osteobiologics in hybrid surgery (combined anterior cervical discectomy and fusion (ACDF) and total disc replacement (TDR)) in patients with multilevel cervical degenerative disc disease (DDD). PubMed and Embase were searched between January 2000 and August 2020. Clinical studies investigating 18-80 year old patients with multilevel cervical DDD who underwent hybrid surgery with or without the use of osteobiologics were considered eligible. Two reviewers independently screened and assessed the identified articles. The methodological index for non-randomized studies (MINORS) tool and the risk of bias (RoB 2.0) assessment tool were used to assess risk of bias. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was used to evaluate quality of evidence across studies per outcome. Eleven studies were included. A decrease in cervical range of motion was observed in most studies for both the hybrid surgery and the control groups consisting of stand-alone ACDF or TDR. Fusion rates of 70-100% were reported in both the hybrid surgery and control groups consisting of stand-alone ACDF. The hybrid surgery group performed better or comparable to the control group in terms of adjacent segment degeneration. Studies reported an improvement in visual analogue scale for pain and neck disability index values after surgery compared to preoperative scores for both treatment groups. The included studies had moderate methodological quality. There is insufficient evidence for assessing the use of osteobiologics in multilevel hybrid surgery and additional high quality and controlled research is deemed essential.

ID: 215795 Occipital Nerve Stimulator After Cervical Fusion for Cervicogenic Headaches

A 50-year-old male with severe multilevel cervical degenerative disc disease and disc herniation requiring discectomy and fusion at C3- T1 presented to the clinic due to constant severe headaches for 3 months post-surgery. He had throbbing pain mainly located along the cervical paraspinals and occipitalis. He tried multiple oral pain medications with minimal relief. The patient had also tried multiple occipital nerve blocks with minimal relief. The pain was thought to be originating from the cervical fusion coming specifically from the C2-C3. The third occipital nerve is the superficial medial branch of the C3 dorsal ramus. It supplies part of the semispinalis capitis muscle leading to the occipital neuralgia that he was experiencing. It was thought the patient would be a great candidate for an occipital nerve stimulator. The nerve stimulator leads were placed in a horizontal orientation at the base of the skull across from where the greater occipital nerve emerges.

Hybrid cervical spine surgery for the treatment of multilevel cervical degenerative disc disease

The optimal surgical treatment for multilevel cervical degenerative disc disease is still controversial. The purpose of this article is to review the current evidence of the hybrid cervical surgery, which combines anterior cervical discectomy and fusion and cervical disc arthroplasty, for treating this condition. This fusion-nonfusion hybrid procedure provides favorable biomechanics and promising clinical and radiographic outcomes in both contiguous and skip-level pathologies. However, further high-quality and long-term follow-up studies are required to provide strong evidence and validate the results of the hybrid cervical spine surgery.

Safety And Efficacy of Hybrid Surgery in Multilevel Cervical Degenerative Disc Disease: Long-Term Follow-up

Safety And Efficacy of Hybrid Surgery in Multilevel Cervical Degenerative Disc Disease: Long-Term Follow-up

Hybrid Implants in Anterior Cervical Spine Surgery: The State of the Art and New Trends for Multilevel Degenerative Disc Disease.

Anterior cervical discectomy and fusion (ACDF) still represents the first surgical option in the treatment of cervical degenerative disc disease (DDD) but is still burdened by several complications secondary to the loss of mobility at the treated segment and adjacent segment diseases (ASDs). To overcome those complications, hybrid surgery (HS) incorporating ACDF and cervical disc arthroplasty (CDA) is increasingly performed for DDD. We retrospectively reviewed the clinical, surgical, and outcome data of 85 consecutive patients (M/F, 41/44) harboring cervical disc herniation with or without osteophytes, with radiculopathy and with or without myelopathy, who underwent the anterior approach to a cervical discectomy on two or more levels with at least one disc prosthesis, along with a cage and plate or an O Profile screwed plate. All the patients improved regardless of the cervical construct used. No significant relationship between different kinds of prosthesis and their surgical level; the number of cages; and the site of the cages (screwed and/or plated) was found concerning immediate stability, dynamic prosthesis effectiveness, and clinical improvement in all the patients up to the maximum follow-up time. Although the optimal surgical technique for cervical DDD remains controversial, HS represents a safe and effective procedure in select patients with multilevel cervical DDD, as demonstrated by biomechanical and clinical studies and the present series.

Research protocol: Cervical Arthroplasty Cost Effectiveness Study (CACES): economic evaluation of anterior cervical discectomy with arthroplasty (ACDA) versus anterior cervical discectomy with fusion (ACDF) in the surgical treatment of cervical degenerative disc disease — a randomized controlled trial

IntroductionTo date, there is no consensus on which anterior surgical technique is more cost-effective in treating cervical degenerative disc disease (CDDD). The most commonly used surgical treatment for patients with single- or multi-level symptomatic CDDD is anterior cervical discectomy with fusion (ACDF). However, new complaints of radiculopathy and/or myelopathy commonly develop at adjacent levels, also known as clinical adjacent segment pathology (CASP). The extent to which kinematics, surgery-induced fusion, natural history, and progression of disease play a role in the development of CASP remains unclear. Anterior cervical discectomy with arthroplasty (ACDA) is another treatment option that is thought to reduce the incidence of CASP by preserving motion in the operated segment. While ACDA is often discouraged, as the implant costs are higher while the clinical outcomes are similar to ACDF, preventing CASP might be a reason for ACDA to be a more cost-effective technique in the long term.Methods and analysisIn this randomized controlled trial, patients will be randomized to receive ACDF or ACDA in a 1:1 ratio. Adult patients with single- or multi-level CDDD and symptoms of radiculopathy and/or myelopathy will be included. The primary outcome is cost-effectiveness and cost-utility of both techniques from a healthcare and societal perspective. Secondary objectives are the differences in clinical and radiological outcomes between the two techniques, as well as the qualitative process surrounding anterior decompression surgery. All outcomes will be measured at baseline and every 6 months until 4 years post-surgery.DiscussionHigh-quality evidence regarding the cost-effectiveness of both ACDA and ACDF is lacking; to date, there are no prospective trials from a societal perspective. Considering the aging of the population and the rising healthcare costs, there is an urgent need for a solid clinical cost-effectiveness trial addressing this question.Trial registrationClinicalTrials.gov NCT04623593. Registered on 29 September 2020.

Clinical adjacent segment pathology after anterior cervical discectomy, with and without fusion, for cervical degenerative disc disease: A single center retrospective cohort study with long-term follow-up

IntroductionClinical adjacent segment pathology (CASP) continues to be a cause of concern after anterior surgical treatment for single- or multilevel cervical degenerative disc disease (CDDD). The current literature reports inconsistent incidence rates and contended risk factors in the development of CASP. Research questionThe aim is to determine the incidence of additional CASP-related surgeries after anterior cervical discectomy with fusion (ACDF) or without fusion (ACD) for CDDD. Secondary outcomes include risk factors for the development of CASP and long-term clinical outcomes. Materials & methodsThis is a single-center, retrospective cohort study with a long-term follow up. Patients undergoing ACD(F) for CDDD between January 2012 and December 2019 were included. ResultsA total of 601 patients were included, with an average follow-up period of 5.0 years. Most patients underwent ACDF with stand-alone cages (87.7%). CASP developed in 58 (9.7%) patients, 41 (70.7%) of which required additional adjacent level surgery. ACD significantly accelerated the development of CASP. The C2–C7 Cobb angle appeared less lordotic upon early post-operative imaging in ACDF patients that later-on developed CASP. Baseline degeneration at the index level and adjacent levels was not significantly different between patients with and without CASP. Discussion & conclusionIn this retrospective cohort, we observe a relatively low rate of additional surgery for CASP in ACDF with stand-alone cages. We suggest that surgical technique, fusion, segmental kyphosis and natural degeneration play a multifactorial role in the development of CASP. Complication rates were low and clinical outcomes were similar for all techniques used.

Long-Term Clinical Results with Radiological Correlations After Posterior Foraminotomy for Unilateral Cervical Discopathy

In lateral cervical disc herniations, posterior foraminotomy (PF) provides direct nerve root decompression and maintains segmental mobility. However, partial facetectomy can cause instability. This study evaluated long-term clinical outcomes related to cervical sagittal alignment after PF. The study included 48 consecutive patients with lateral cervical disc herniations who underwent PF. Pain and mobility were evaluated using the Numeric Rating Scale and Neck Disability Index (NDI), respectively. Sagittal alignment was evaluated using the modified Toyama method. Median Numeric Rating Scale arm, Numeric Rating Scale neck, and NDI scores improved by 7, 4.5, and 24 points, respectively. Corresponding mean minimal clinically important differences were achieved in 94%, 77%, and 98% of patients at a mean follow-up of 8.4 years. Of patients, 82% showed favorable radiological results (i.e., retained or developed lordosis or had straight spine), while 18% showed unfavorable radiological results (i.e., retained or changed toward kyphosis). The latter group had multilevel cervical degenerative disc disease (mcDDD) before PF. Nevertheless, the risk of developing kyphosis was only 2.6%, and the potential for improving sagittal balance was 43%. Follow-up median NDI scores, but not minimal clinically important differences, were significantly worse in patients with preoperative kyphosis (21 vs. 8; P= 0.03) or mcDDD (20 vs. 8; P= 0.024) compared with other patients. Patients with preoperative kyphosis or mcDDD had worse NDI outcomes but also benefited from PF. Sagittal alignment improved in >40% of patients, but coexisting mcDDD was a main risk factor for kyphosis persistence.

The impact of smoking on outcomes following anterior cervical fusion-nonfusion hybrid surgery: a retrospective single-center cohort study

BackgroundThere is mixed evidence for the impact of cigarette smoking on outcomes following anterior cervical surgery. It has been reported to have a negative impact on healing after multilevel anterior cervical discectomy and fusion, however, segmental mobility has been suggested to be superior in smokers who underwent one- or two-level cervical disc replacement. Hybrid surgery, including anterior cervical discectomy and fusion and cervical disc replacement, has emerged as an alternative procedure for multilevel cervical degenerative disc disease. This study aimed to examine the impact of smoking on intermediate-term outcomes following hybrid surgery.MethodsRadiographical and clinical outcomes of 153 patients who had undergone continuous two- or three-level hybrid surgery were followed-up to a minimum of 2-years post-operatively. The early fusion effect, 1-year fusion rate, the incidence of bone loss and heterotopic ossification, as well as the clinical outcomes were compared across three smoking status groups: (1) current smokers; (2) former smokers; (3) nonsmokers.ResultsClinical outcomes were comparable among the three groups. However, the current smoking group had a poorer early fusion effect and 1-year fusion rate (P < 0.001 and P < 0.035 respectively). Both gender and smoking status were considered as key factors for 1-year fusion rate. Upon multivariable analysis, male gender (OR = 6.664, 95% CI: 1.248–35.581, P = 0.026) and current smoking status (OR = 0.009, 95% CI: 0.020–0.411, P = 0.002) were significantly associated with 1-year fusion rate. A subgroup analysis demonstrated statistically significant differences in both early fusion process (P < 0.001) and the 1-year fusion rate (P = 0.006) across the three smoking status groups in female patients. Finally, non-smoking status appeared to be protective against bone loss (OR = 0.427, 95% CI: 0.192–0.947, P = 0.036), with these patients likely to have at least one grade lower bone loss than current smokers.ConclusionsSmoking is associated with poor outcomes following hybrid surgery for multilevel cervical disc disease. Current smokers had the poorest fusion rate and most bone loss, but no statistically significant differences were seen in clinical outcomes across the three groups.

Anterior hybrid construction of multilevel cervical disc disease and spondylotic spinal stenosis: surgical results and factors affecting adjacent segment problems

ObjectiveWe aimed to evaluate reliability, radiological outcomes, and the impacts of anterior cervical hybrid construction on the adjacent segments for the multilevel cervical degenerative disc disease (mCDDD) and spondylotic spinal stenosis (SSS).MethodsA retrospective analysis was performed using data extracted from the medical files of 195 patients (105 males, 90 females; mean age: 47.7 years). From 2008 to 2018, these patients underwent anterior cervical hybrid construction for symptomatic contiguous at least 2-level cervical degenerative disc diseases and cervical spondylosis. Clinical and radiological data including Neck Disability Index (NDI), visual analogue scale (VAS), local cervical degenerative disk disease in adjacent segments on magnetic resonance imaging (MRI) views, and complications were reviewed.ResultsThe mean clinical and radiological follow-up was 45.2 months (range 24 to 102). Radiculopathy and/or myelopathy were the main clinical problems in all patients. The mean VAS scores of HC for arm pain were 7.4 ± 0.8 preoperatively; 2.8 ± 0.6, 1 month after surgery; 2.3 ± 0.6, 6 months after surgery; 1.8 ± 0.6, 12 month after surgery; and 1.6 ± 0.6, 24 months after surgery. The mean NDI scores (mean ± SD) of HC significantly improved after surgery (on admission, 57.2 ± 5.5%; 1 month after surgery, 27.35 ± 5.3%; 6 month after surgery, 21.43 ± 2.8%; 12 months after surgery, 21.9 ± 2.3%; 24 months after surgery, 20.6 ± 2.6%, p = 0.006). Hoarseness and dysphagia were the most common complications and osteophyte formation was the most frequent radiographic change.ConclusionAnterior cervical hybrid construction appears to be an acceptable option in the management of multilevel cervical degenerative disc diseases and spondylotic spinal stenosis.

Hybrid implants in anterior cervical decompressive surgery for degenerative disease

Background:Anterior cervical discectomy and fusion (ACDF) still represent the mainstream surgical approach in the treatment of degenerative cervical Degenerative Disc Disease (DDD), being a loss of mobility at the treated segment and adjacent segment diseases well-known complications. To overcome those complications, hybrid surgery (HS) incorporating ACDF and cervical disk arthroplasty is increasingly performed for DDD.Methods:We retrospectively reviewed the clinical, surgical, and outcome data of 62 consecutive patients (male/female, 29/37) harboring cervical disk herniation with or without osteophytes, with radiculopathy with or without myelopathy, who underwent a cervical discectomy on two or more levels with the anterior approach with at least one disk prosthesis along with cage and plate or O Profile screwed plate.Results:All the patients improved regardless of the cervical construct used. No significant relationship between different kind of prostheses as well as their surgical level, the number and the site of the cages (screwed and/or plated) was found out concerning immediate stability, dynamic prosthesis effectiveness, and clinical improvement in all the patients up to the maximum follow-up.Conclusions:Although the optimal surgical technique for cervical DDD remains controversial, HS represents a safe and effective procedure in selected patients with multilevel cervical DDD, as demonstrated by biomechanical and clinical studies and the present series. Some technical aspects should be considered when dealing with this procedure, like the drilling of the endplate, and some radiological findings have to be detected because potentially predictive of future misplacement.

Is Cervical Disc Replacement Valuable in 3-Level Hybrid Surgery Compared with 3-Level Anterior Cervical Discectomy and Fusion?

Cervical degenerative disc disease is common in clinical practice. Surgery is among the most effective treatments for patients with cervical radiculopathy, myelopathy, or stenosis. Which treatment is the best option for multilevel cervical degenerative disc disease is controversial. Hybrid surgery, combined cervical disc replacement and anterior cervical discectomy and fusion, may be an alternative treatment for multilevel cervical degenerative disc disease. Sixty-four patients with 3-level hybrid surgery and 37 patients with 3-level anterior cervical discectomy and fusion were reviewed retrospectively. Clinical outcomes were based on visual analog scale, Neck Disability Index, 36-Item Short Form Survey, and Japanese Orthopaedic Association scores and Japanese Orthopaedic Association recovery rate. Radiologic assessments included range of motion (ROM) of C2-C7 and adjacent level and cervical lordosis of C2-C7. Perioperative parameters, fusion condition, and complications were assessed. There were no statistical differences observed between the 2 groups for Japanese Orthopaedic Association, Neck Disability Index, or visual analog scale scores. The hybrid surgery group had better physical and mental 36-Item Short Form Survey scores than the fusion group at 1-year follow-up (physical component summary: 49.34 vs. 46.70, P= 0.012; mental component summary: 45.67 vs. 43.95, P= 0.004). ROM of C2-C7 and adjacent levels was less compromised in the hybrid group compared with baseline (64.60% vs. 51.34%, P < 0.001). Cervical lordosis was decreased with time in both groups but was acceptable at final follow-up, and both groups showed solid fusion. Normal ROM and solid fusion were achieved at both arthroplasty and arthrodesis levels. ROM of replacement levels in different locations of the 3-level construct was acceptable.

Association between anterior bone loss and anterior heterotopic ossification in hybrid surgery

BackgroundHybrid surgery (HS) has become an alternative procedure for the treatment of multilevel cervical degenerative disc disease with satisfactory outcomes. However, some adverse outcomes have recently emerged, such as heterotopic ossification (HO) and anterior bone loss (ABL). Furthermore, HO was found mostly located in the posterior and lateral of the cervical intervertebral disc space. The mechanism of anterior heterotopic ossification (AHO) formation may be different, and its relationship with ABL was uncertain.MethodsRadiographical and clinical outcomes of ninety-seven patients who had undergone contiguous two-level HS between December 2010 and December 2017 and with a minimum of 2-year follow-up were analyzed. Postoperative radiographs were evaluated and compared to the initial postoperative films to determine the incidence of ABL and AHO.ResultsThe overall incidence rate of ABL was 44.3% (43/97). It was identified in 70.6% of AHO cases (33.3% mild, 41.7% moderate, 25.0% severe) and 38.8% of non-AHO cases (38.7% mild, 45.2% moderate, 16.1% severe). A significant association between ABL and AHO occurrence was found (P = 0.016). There was no significant difference in prosthesis–endplate depth ratio or disc space angle change between the AHO group and the non-AHO group (P > 0.05). Compared with data preoperatively, clinical outcome scores significantly improved after surgery in both the AHO and non-AHO groups, with no significant differences between the two groups (P > 0.05).ConclusionABL was common in HS, and it related to AHO. The formation of AHO could be an integral part of postoperative bone remodeling, as well as ABL.

251. Location of the fused level does not affect the behavior of disc replacement adjacent to fusion in hybrid surgery

BACKGROUND CONTEXT Hybrid surgery (HS), consisting of cervical disc arthroplasty (CDA) at the mobile level, along with anterior cervical discectomy and fusion (ACDF) at the spondylotic level, could be a promising treatment for patients with multilevel cervical degenerative disc disease (DDD). An advantage of this technique is that it utilizes an optimal procedure according to the status of each level. However, information is lacking regarding the influence of the relative location of the replacement and the fusion segment in vivo. PURPOSE To investigate whether the location of the fusion affected the behavior of the disc replacement and adjacent segments in HS in vivo. STUDY DESIGN/SETTING This is an observational study. PATIENT SAMPLE The numbers of patients in the arthroplasty-fusion (AF) and fusion-arthroplasty (FA) groups were 51 and 24, respectively. OUTCOME MEASURES The Japanese Orthopedic Association (JOA), neck disability index (NDI) and visual analogue scale (VAS) were evaluated. Global and segmental lordosis, the range of motion (ROM) of C2-C7, and the operated and adjacent segments were measured. Fusion rate and radiological changes at adjacent levels were observed. METHODS Between January 2010 and July 2016, 75 patients with cervical DDD at two contiguous levels undergoing two-level HS were retrospectively reviewed. The patients were divided into AF and FA groups according to the locations of the disc replacement. Clinical outcomes were evaluated according to the JOA, NDI, and VAS. Radiological parameters, including global and segmental lordosis, the ROM of C2- C7, the operated and adjacent segments, and complications, were also evaluated RESULTS Although the JOA, NDI and VAS scores were improved in both the AF and FA groups, no significant differences were found between the two groups at any follow-up point. Both groups maintained cervical lordosis, but no difference was found between the groups. Segmental lordosis at the fusion segment was significantly improved postoperatively (P CONCLUSIONS In HS, cephalic or caudal fusion segments to the arthroplasty segment did not affect the clinical outcomes and the behavior of CDA. However, the ROM of adjacent segments was affected by the location of the fusion segment; segments adjacent to fusion segments had greater ROMs than segments adjacent to arthroplasty segments. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Letter to the Editor Regarding “Comparison of Different Hybrid Techniques for the Treatment of Multi-level Cervical Degenerative Disc Disease—Analysis of Prospectively Collected Clinical, Radiological, and Psychological Parameters”

Letter to the Editor Regarding “Comparison of Different Hybrid Techniques for the Treatment of Multi-level Cervical Degenerative Disc Disease—Analysis of Prospectively Collected Clinical, Radiological, and Psychological Parameters”

Letter to the Editor Regarding “Comparison of Different Hybrid Techniques for the Treatment of Multilevel Cervical Degenerative Disc Disease—Analysis of Prospectively Collected Clinical, Radiologic, and Psychological Parameters”

Letter to the Editor Regarding “Comparison of Different Hybrid Techniques for the Treatment of Multilevel Cervical Degenerative Disc Disease—Analysis of Prospectively Collected Clinical, Radiologic, and Psychological Parameters”

Multilevel Cervical Disc Arthroplasty: Long-Term Outcomes at 3 and 4 Levels.

Multilevel cervical degenerative disc disease in 2 or more segments poses treatment challenges. Anterior cervical discectomy and fusion is a viable treatment option, but one with high rates of adjacent segment disease and pseudoarthrosis. Cervical disc arthroplasty (CDA) is approved by the US Food and Drug Administration for the treatment of 1- and 2-level cervical pathology, with established long-term safety and effectiveness. Limited evidence exists for CDA at more than 2 levels. This study investigates the long-term outcomes of 3- and 4-level CDA out to 7 years. In a retrospective review of prospectively collected data, patient demographics and surgical characteristics were collected. Patient-reported outcomes (PROs) were collected preoperatively and at 6 weeks, 3 months, 6 months, and 12 months postoperatively, and annually thereafter, including: Neck Disability Index (NDI), numeric rating scales for neck pain and arm pain, the Veterans Rand 12-item Health Survey physical component summary (PCS) score and mental component summary (MCS) score, and patient satisfaction scores. Secondary surgery data were also collected. Predictive methods using mixed-effects regression models were used to analyze the data. Data for 139 CDAs were available for evaluation (n = 116 three-level and n = 23 four-level). Statistical improvement was shown for all PRO scores at all postoperative intervals (P < .001). From preoperatively to 7 years postoperatively, mean NDI decreased from 57.9 to 31.3 (45.9% improvement), mean neck pain decreased from 15.6 to 7.9 (49.4% improvement), mean arm pain decreased from 12.2 to 5.6 (54.1% improvement), mean PCS increased from 29.2 to 41.4 (41.8% improvement), and mean MCS increased from 37.1 to 44.5 (19.9% improvement). Five (3.6%) 3-level patients underwent secondary surgery. Patient satisfaction exceeded 88% 7 years after surgery. Statistical improvement in PROs, with a low rate of secondary surgeries out to 7 years, demonstrates that 3- and 4-level CDA may be performed safely and effectively in appropriately selected patients. 4.

Comparison of Different Hybrid Techniques for the Treatment of Multilevel Cervical Degenerative Disc Disease–Analysis of Prospectively Collected Clinical, Radiologic, and Psychological Parameters

Conventional surgical treatment of multilevel cervical disc disease is based on anterior cervical discectomy and fusion (ACDF). However, fusion alters the biomechanics of the spine, potentially resulting in accelerated adjacent segment degeneration. To improve clinical outcomes, hybrid surgery, combining cervical disc arthroplasty with fusion, has been developed. Cervical total disc replacement (TDR) has been shown to keep the motion of adjacent segment, and a dynamic cervical implant (DCI) was shown to provide cervical dynamic stability under nonfusion. However, curative and unwanted side effects of the new therapy options TDR and DCI for treating multilevel cervical degenerative disc disease are still unknown. This analysis is based on 88 patients treated for multilevel cervical degenerative disc disease with ACDF only (56 patients), DCI hybrid (17 patients), and TDR hybrid (15 patients) between June 2008 and November 2015. The mean follow-up was 19.5 months. Visual analog scale (VAS), Neck Disability Index, and quality-of-life measurements were assessed via questionnaires. The VAS scores decreased significantly in all 3 groups (P < 0.001), but the TDR group showed the greatest reduction in VAS score compared with ACDF and DCI (both P < 0.05). The overall range of motion (ROM) and the segmental ROM at the treated levels showed significant decreases in all 3 groups. Although there was no difference in the overall ROM at final follow-up among the operatively treated groups, the ROM of the treated segment was lowest in the ACDF group (P= 0.002). In terms of heterotopic ossification, patients undergoing TDR showed the best prognosis. These results indicate that both TDR hybrid and DCI hybrid are effective and safe procedures for the treatment of multilevel degenerative disc disease. However, there is no definitive evidence that DCI or TDR arthroplasty lead to better intermediate-term results than ACDF over an average observation time of 19.5 months.

The safety and efficacy of hybrid surgery for multilevel cervical degenerative disc disease versus anterior cervical discectomy and fusion or cervical disc arthroplasty: a systematic review and meta-analysis.

Multilevel cervical degenerative disc disease (CDDD) can be treated surgically with anterior cervical discectomy and fusion (ACDF), cervical disc arthroplasty (CDA), or a hybrid surgery (HS) of the two in which both procedures are used at different vertebral levels. A systematic review and meta-analysis was performed to compare the clinical and radiographical outcomes of HS against ACDF or CDA alone. Three electronic databases were searched for articles published before December 2018. The literature was searched and assessed by independent reviewers according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Eight papers were identified as eligible with a total of 424 patients. Post-operative C2-C7 range of motion (ROM) was significantly greater after HS than ACDF (p = 0.004; mean difference (MD) 6.14°). The ROM of the superior adjacent segment was significantly lower after HS than ACDF (p < 0.0001; MD - 2.87°) as was the ROM of the inferior adjacent segment (p = 0.0005; MD - 3.11°). HS patients' return to work was shorter than those who underwent ACDF (p < 0.00001; MD - 32.01 days) and CDA (p < 0.00001; MD - 32.92 days). There were no statistically significant differences in functional outcomes following CDA compared with HS. There was no significant difference in operation time, intra-operative blood loss, or post-operative complications between any of the procedures. The number of included studies was small, the heterogeneity between them was substantial, and the quality of evidence was very low. Large randomised controlled trials are required to provide strong evidence that would enable recommendation of one intervention over another.