SWISSspine: the case of a governmentally required HTA-registry for total disc arthroplasty: results of cervical disc prostheses

Patient-Reported Outcome Measures in High-Risk Medical Device Registries: A Scoping Review

Little is known about the methods and outcomes of patient-reported outcome measure (PROM) use among high-risk medical device registries. The objective of this scoping review was to assess the utility and predictive ability of PROMs in high-risk medical device registries. We searched Ovid Medline, Embase, APA PsychINFO, Cochrane Library, and Scopus databases for published literature. After searching, 4323 titles and abstracts were screened, and 262 full texts were assessed for their eligibility. Seventy-six papers from across orthopedic (n = 64), cardiac (n = 10), penile (n = 1), and hernia mesh (n = 1) device registries were identified. Studies predominantly used PROMs as an outcome measure when comparing cohorts or surgical approaches (n = 45) or to compare time points (n = 13) including pre- and postintervention. Fifteen papers considered the predictive ability of PROMs. Of these, 8 treated PROMs as an outcome, 5 treated PROMs as a risk factor through regression analysis, and 2 papers treated PROMs as both a risk factor and as an outcome. One paper described PROMs to study implant survival. To advance methods of PROM integration into clinical decision-making for medical devices, an understanding of their use in high-risk device registries is needed. This scoping review found that there is a paucity of studies using PROMs to predict long-term patient and clinical outcomes in high-risk medical device registries. Determination as to why PROMs are rarely used for predictive purposes in long-term data collection is needed if PROM data are to be considered suitable as real-world evidence for high-risk device regulatory purposes, as well as to support clinical decision-making.

Level of Evidence 4

Does anxiety influence the prognosis of percutaneous transforaminal endoscopic discectomy in the treatment of lumbar disc herniation? A preliminary propensity score matching analysis

PURPOSE

Previous reports revealed a correlation between psychological problems and spinal surgery. There is a lack of knowledge on the effect of anxiety on the percutaneous transforaminal endoscopic discectomy (PTED) outcome at the two year follow-up. The purpose of this study is to investigate changes in anxiety after PTED among patients with lumbar disc herniation (LDH), to compare the effect of anxiety on the prognosis using propensity score matching analysis, and to identify the related parameters of anxiety.

METHODS

A total of 145 patients with LDH requiring PTED surgery were included. Twenty-six LDH patients with anxiety were matched with 26 control patients utilizing propensity score matching analysis. The demographic and peri-operative data were collected and analyzed. A correlation analysis was utilized.

RESULTS

Both groups achieved significant improvements in visual analogue scale (VAS) scores for pain, Japanese Orthopedic Association (JOA) scores for neurological deficit, and 36-item Short-Form Health Survey (SF-36) scores and Oswestry Disability Index (ODI) scores for quality of life. A statistical difference was detected between the pre-operative and the post-operative Zung Self-Rating Anxiety Scale scores in the anxiety cohort. However, the difference between the anxiety group and the control group was statistically significant in the aforementioned parameters. The VAS, JOA, ODI and the SF-36 scores, and the disease duration were associated with pre-operative anxiety.

CONCLUSION

PTED may provide significant improvements in clinical outcomes and symptoms of anxiety. A negative impact on the patient's prognosis may be caused by the presence of anxiety. Pain severity, neurological deficit, disease duration, and quality of life were associated with anxiety.

NuNec™ Cervical Disc Arthroplasty Improves Quality of Life in Cervical Radiculopathy and Myelopathy: A 2-yr Follow-up

BACKGROUND

Anterior cervical disc replacement is an alternative to fusion for the treatment of selected cases of radiculopathy and myelopathy. We report clinical and radiological outcomes after disc replacement with the NuNec™ artificial cervical disc (Pioneer® Surgical Technology, Marquette, Michigan) with subgroup analysis.

OBJECTIVE

To review clinical and radiological outcomes after anterior cervical disc replacement with the NuNec™ artificial cervical disc.

METHODS

A consecutive case series of patients undergoing cervical disc replacement with the NuNec™ artificial disc was conducted. Clinical outcomes were assessed by questionnaires preoperatively and up to 2 yr postoperatively including neck and arm pain, Neck Disability Index, Euroqol 5-dimensions, and Short Form-36; x-rays from the same period were analyzed for range of movement and presence of heterotopic ossification.

RESULTS

A total of 44 NuNec™ discs were implanted in 33 patients. Clinical improvements were seen in all outcomes; significant improvements on the Neck Disability Index, Euroqol 5-dimensions, and physical domain of the Short Form-36 were maintained at 2 yr. There was a mean of 4° range of movement at the replacement disc level at 2 yr, a significant reduction from baseline; there was also progression in levels of heterotopic ossification. Complications included temporary dysphagia (10%) and progression of disease requiring foraminotomy (6%); no surgery for adjacent level disease was required. There was no significant difference in the outcomes of the radiculopathy and myelopathy groups.

CONCLUSION

Clinical outcomes using the NuNec™ disc replacement are comparable with other disc replacements. Although the range of movement is reduced, the reoperation rate is very low.

Quality of Life Following Prestige LP Cervical Disc Arthroplasty in a Prospective Multicountry Study

Background

To describe routine surgical practice using Prestige LP Cervical Disc (Prestige disc) and patient outcomes for degenerative cervical disc disease in a multicenter 2-year prospective, observational study.

Methods

Patient demographics and intraoperative data were collected; quality of life (QoL) (EQ-5D, EQ-VAS, and neck disability index), average disc height, and adverse events were assessed pre- and postoperatively at 3, 6, 12, and 24 months.

Results

One hundred and ninety-four patients were enrolled (190 patients implanted; female: 67%; mean age: 44.0 years; mean body mass index: 25.6). Disc herniation was the most frequent indication for cervical arthroplasty (80.5%). Thirty-seven percent of patients experienced pain for >1 year prior to baseline assessment. Mean procedure duration was 87.1 minutes, and mean blood loss was 43.8 mL. The majority (71.0%) of Prestige discs were implanted at level C5 to C6, while 16.3% of patients received implants at 2 levels. There was a significant improvement from baseline to 3, 6, 12, and 24 months of follow-up in all QoL assessments. After implantation, the mean disc height at the affected level increased by 0.19 from baseline (0.22) to 3 months (0.41) and remained constant up to 24 months (P < .001). Mean disc height of levels above and below the implant remained comparable at baseline and follow-up. A total of 63 adverse events (44 patients) was recorded, of which 7 (11.1%) were related to the Prestige disc, instrumentation, or procedure; 41 (65.1%) were unrelated; and 15 (23.8%) had an unknown relation.

Conclusions

In line with published findings, our study shows significant improvement in outcomes in the first 3 months after Prestige disc implantation with improvements maintained throughout the study.

The association between preoperative mental distress and patient-reported outcome measures in patients treated surgically for cervical radiculopathy

BACKGROUND CONTEXT

Previous research indicates that there might exist a link between the experience of pain and mental distress. Pain can possibly trigger anxiety and chronic pain, as well as also depression. On the other hand, anxiety and depression might also be risk factors for painful conditions and more pronounced subsequent disability and thus, the pathways may be bidirectional. Expanded knowledge of how different factors affect pain and function may help surgeons in preoperative decision-making.

PURPOSE

The aim of this study was to evaluate the impact of potential preoperative risk factors with special reference to mental distress.

STUDY DESIGN/SETTING

This is a prospective outcome study in a cohort from a multicenter randomized controlled trial comparing anterior cervical decompression and fusion with disc replacement.

PATIENT SAMPLE

The sample included 151 patients with cervical radiculopathy planned for surgery.

OUTCOME MEASURES

Surgical outcome was evaluated with Neck Disability Index (NDI), health related quality-of-life with European Quality of Life-5 Dimensions, and pain with visual analogue scale for arm and neck. Mental distress was preoperatively measured with the Hospital Anxiety and Depression (HAD) scale.

METHODS

Preoperative data regarding possible risk factors for poor outcome were analyzed in multiple linear regression models with postoperative NDI and change of NDI as dependent factors. Patients with high preoperative levels of anxiety or depression (H-HAD), indicating mental distress, were compared with patients scoring low/moderate levels (L-HAD) regarding patient-reported outcome measures (PROMs) preoperatively and at 1- and 2-year follow-up.

RESULTS

Outcome data were available for 136 patients at the 2-year follow-up. No statistically significant difference in any outcome data could be demonstrated between the two surgical treatment groups. Mental distress was the variable most strongly associated with NDI at 2 years in the regression analysis. There were 42 patients classified as H-HAD and 94 as L-HAD. The average improvement in NDI was 16.9 in the H-HAD group and 26.3 in the L-HAD group, p=.02. The H-HAD patients showed a tendency for poorer baseline data and worse outcome overall in all PROMs at follow-up at both 1 and 2 years.

CONCLUSIONS

Preoperative mental distress measured with HAD was associated with worse outcome overall. More research is needed to investigate whether patients with mental distress may achieve better results if other treatments are offered, either as non-surgical treatment alone or as an adjunct to surgery.

Cervical disc replacement surgery: biomechanical properties, postoperative motion, and postoperative activity levels

PURPOSE OF REVIEW

Cervical disc arthroplasty (CDA) is an evolving technique used in the treatment of cervical disc disease. To remain up to date on studies regarding its efficacy, we sought to answer three questions: What do biomechanical studies demonstrate in regard to the kinematics of CDA? How does CDA affect cervical motion? What are the postoperative activity levels of patients after cervical disc arthroplasty?

RECENT FINDINGS

1) In regard to biomechanics, recent data suggests that CDA maintains motion while possibly altering facet biomechanics. 2) Radiographic data indicates a reliable maintenance of motion in the short and medium term. 3) Postoperative activity levels are assessed with clinical outcome data which demonstrate reliable improvement in pain and function. The data reviewed here establishes CDA as an efficacious treatment in the relief of symptoms from CDD. It is important to note however that an evaluation of CDA would benefit from more robust data, specifically in regards to long-term clinical outcomes.

Impact of Axial Neck Pain on Quality of Life After Laminoplasty

STUDY DESIGN

A prospective study.

OBJECTIVE

The aim of this study was to elucidate the impact of axial pain following cervical laminoplasty on health-related quality of life (HRQOL).

SUMMARY OF BACKGROUND DATA

Axial neck pain is a frequently encountered complication after laminoplasty. However, limited information is available regarding the time-dependent changes in axial pain and the impact of this pain on clinical outcomes, including HRQOL.

METHODS

One hundred sixty-two consecutive patients with cervical myelopathy underwent double-door laminoplasty using hydroxyapatite spacers from 2008 to 2012. The outcome measures included the Japanese Orthopaedic Association score (JOA score), the EuroQol 5 Dimension Questionnaire (EQ-5D), and the Short Form-36 survey (SF-36). The intensity of axial pain was assessed using an 11-point numerical rating scale (NRS). These assessments were conducted preoperatively and at 6-month, 1-year, and 2-year follow-ups. Patient satisfaction with outcome was graded using a 7-point NRS at the 2-year follow-up.

RESULT

One hundred twenty-one patients completed the 2-year follow-up. The mean axial pain intensity decreased slightly over time; however, the decrease was not significant. The JOA score, EQ-5D score, and all SF-36 domains, excluding general health perceptions, improved significantly compared with baseline levels at the 6-month follow-up or later. Baseline axial pain intensity showed a significant negative correlation with baseline HRQOL only in the SF-36 bodily pain domain. In contrast, axial pain intensity showed significant negative correlations with all HRQOL measures at the 6-month follow-up. At the 2-year follow-up, patients with an axial pain intensity ≥3 showed significantly worse outcomes than did patients with a pain intensity <3 in the EQ-5D score, SF-36 score, and patient satisfaction grades, but not in the JOA score.

CONCLUSION

Axial neck pain has a significant negative impact on clinical outcomes, including a wide range of HRQOL measures and patient satisfaction with outcome, in patients undergoing conventional double-door laminoplasty.

LEVEL OF EVIDENCE

3.

DEVELOPMENT OF COVERAGE WITH EVIDENCE DEVELOPMENT FOR MEDICAL TECHNOLOGIES IN SWITZERLAND FROM 1996 TO 2012

Objectives: The aim of this study was to assess incidence, time frame, and outcome of “Coverage with Evidence Development” (CED) decisions in the Swiss Basic Health Insurance scheme.

Methods: Analysis of all controversial medical technologies submitted to review by the Swiss Federal Office of Public Health (FOPH) from 1996 to 2012 with focus on decisions with constraints. Description of types of technology, type of initial decision, duration of evaluation period, final decision, and search for potential factors associated with changes over time.

Results: Forty-five (37.5 percent) of 120 controversial health technologies were classified as “yes, in evaluation, reimbursed” for a certain period of time and thirty-five (29.2 percent) as “no, in evaluation, not reimbursed” by the Federal Department of Home Affairs from 1996 to 2012. The rate of CED decisions ranged between zero and nine per year and was influenced by type of technology and calendar year. Forty-four of forty-five decisions were subject to further restrictions, to a “center or a specialist” (76 percent), “indications” (49 percent), “registry” (31 percent), or “other” (49 percent). The time to a final decision ranged from 1.5 to 11 years (median, 6 years). No factors associated with initial decision and final outcome could be identified.

Conclusions: CED as a reality in Switzerland might have enabled patients to obtain access to promising technologies early in their life cycle. CED might have acted as a trigger to a successful implementation of a comprehensive national registry. The lack of qualitative data stresses the urgent need for evaluation of the HTA decisions and their impact on patient outcome and costs.

Factor analysis of the North American Spine Society outcome assessment instrument: a study based on a spine registry of patients treated with lumbar and cervical disc arthroplasty

BACKGROUND CONTEXT

Studies involving factor analysis (FA) of the items in the North American Spine Society (NASS) outcome assessment instrument have revealed inconsistent factor structures for the individual items.

PURPOSE

This study examined whether the factor structure of the NASS varied in relation to the severity of the back/neck problem and differed from that originally recommended by the developers of the questionnaire, by analyzing data before and after surgery in a large series of patients undergoing lumbar or cervical disc arthroplasty.

STUDY DESIGN/SETTING

Prospective multicenter observational case series.

PATIENT SAMPLE

Three hundred ninety-one patients with low back pain and 553 patients with neck pain completed questionnaires preoperatively and again at 3 to 6 and 12 months follow-ups (FUs), in connection with the SWISSspine disc arthroplasty registry.

OUTCOME MEASURES

North American Spine Society outcome assessment instrument.

METHODS

First, an exploratory FA without a priori assumptions and subsequently a confirmatory FA were performed on the 17 items of the NASS-lumbar and 19 items of the NASS-cervical collected at each assessment time point. The item-loading invariance was tested in the German version of the questionnaire for baseline and FU.

RESULTS

Both NASS-lumbar and NASS-cervical factor structures differed between baseline and postoperative data sets. The confirmatory analysis and item-loading invariance showed better fit for a three-factor (3F) structure for NASS-lumbar, containing items on "disability," "back pain," and "radiating pain, numbness, and weakness (leg/foot)" and for a 5F structure for NASS-cervical including disability, "neck pain," "radiating pain and numbness (arm/hand)," "weakness (arm/hand)," and "motor deficit (legs)."

CONCLUSIONS

The best-fitting factor structure at both baseline and FU was selected for both the lumbar- and cervical-NASS questionnaires. It differed from that proposed by the originators of the NASS instruments. Although the NASS questionnaire represents a valid outcome measure for degenerative spine diseases, it is able to distinguish among all major symptom domains (factors) in patients undergoing lumbar and cervical disc arthroplasty; overall, the item structure could be improved. Any potential revision of the NASS should consider its factorial structure; factorial invariance over time should be aimed for, to allow for more precise interpretations of treatment success.

Total cervical disk replacement with a prestige LP® prosthesis: clinical and functional outcomes

Objective: To determine the clinical and functional results of short- and medium-term cervical arthroplasty with the Prestige LP® prosthesis for the treatment of compressive myelopathy, radiculopathy and axial pain with radiculopathty. Methods: This retrospective study, conducted from 2009 to 2012, included 18 patients. Only 16 were found for the second stage of research, conducted in 2011 and 2012. Pre- and postoperative assessments were carried out using the CSOQ (Cervical Spine Outcomes Questionnaire). Odom criteria were used only in the postoperative evaluation. Both were translated and adapted to the local culture. Results: There was no postoperative radiculopathy or other complications requiring prolonged hospitalization. In most patients, there was a significant improvement in axial pain and radiculopathy, and there was only one indication of conversion to fusion. Conclusions: In selected cases of cervical degenerative disc disease, herniated cervical disc and compressive myeolopathy, cervical arthroplasty proved to be an effective and safe treatment in the short and medium terms.

Five-year results of cervical disc prostheses in the SWISSspine registry

BACKGROUND

The Swiss Federal Office of Public Health demanded a nationwide HTA-registry for cervical total disc arthroplasty (TDA), to decide about its reimbursement. The goal of the SWISSspine registry is to generate evidence about the safety and efficiency of cervical TDA.

MATERIALS AND METHODS

Three hundred thirty-two cases treated between 3.2005 and 6.2006 who were eligible for 5 years follow-ups were included in the study. Follow-up rates for 3-6 months, 1, 2 and 5 years were 84.6, 74.4, 50.6 and 64.8 %, respectively. Outcome measures were neck and arm pain, medication, quality of life, intraoperative and postoperative complication and revision rates. In addition, segmental mobility, ossification, adjacent and distant segment degeneration were analyzed at the 5-year follow-up.

RESULTS

There was significant, clinically relevant and lasting reduction of neck (preop/postop 60/21 VAS points) and arm pain (preop/postop VAS 67/17) and a consequently decreased analgesics consumption and quality of life improvement (preop/postop 0.39/0.82 EQ-5D points) until the 5-year follow-up. The rates for intraoperative and early postoperative complications were 0.6 and 7.2 %, respectively. In 0.6 % an early and in 3.9 % a late revision surgery was performed. At the 5-year follow-up, the average range of motion of the mobile segments (88.2 %) was 10.2°. In 40.7 % of the patients osteophytes at least potentially affecting range of motion were seen.

CONCLUSIONS

Cervical TDA appeared as safe and efficient in long-term pain alleviation, consequent reduction of pain killer consumption and in improvement of quality of life. The improvement is stable over the 5 years postoperative period. The vast majority of treated segments remained mobile after 5 years, although 40.7 % of patients showed osteophytes.

Artroplastia total de disco cervical com prótese de Bryan: resultados clínicos e funcionais

OBJETIVO: Avaliar resultados da artroplastia total disco cervical com a prótese de Bryan para tratamento da cervicobraquialgia (radiculopatia) e da mielopatia compressiva. MÉTODOS: No período de 2002 a 2007, a equipe da CECOL operou 65 pacientes. Somente 28 pacientes foram localizados em 2010 para uma nova coleta de dados. Foi feita avaliação pré e pós-operatória, utilizando-se o questionário CSOQ (Cervical Spine Outcomes Questionnaire). Os critérios de Odom foram utilizados somente na avaliação pós-operatória. Ambos foram traduzidos e adaptados para cultura local. RESULTADOS: Houve melhora funcional e sintomática significativa na maioria dos pacientes. A atenuação da dor cervical (axial) e braquial (radicular) foi semelhante. Os critérios Odom indicaram 82,1% de bons e ótimos resultados, 10% satisfatórios e 7% ruins. Houve apenas uma complicação (3%), que foi revertida com a artrodese anterior. CONCLUSÕES: A artroplastia total de disco cervical demonstrou ser um método seguro e eficaz para tratamento de casos selecionados de hérnia de disco cervical associada a radiculopatia e/ou mielopatia a curto e médio prazo.

Comparative effectiveness research across two spine registries

BACKGROUND

Comparative effectiveness research in spine surgery is still a rarity. In this study, pain alleviation and quality of life (QoL) improvement after lumbar total disc arthroplasty (TDA) and anterior lumbar interbody fusion (ALIF) were anonymously compared by surgeon and implant.

METHODS

A total of 534 monosegmental TDAs from the SWISSspine registry were analyzed. Mean age was 42 years (19-65 years), 59% were females. Fifty cases with ALIF were documented in the international Spine Tango registry and used as concurrent comparator group for the pain analysis. Mean age was 46 years (21-69 years), 78% were females. The average follow-up time in both samples was 1 year. Comparison of back/leg pain alleviation and QoL improvement was performed. Unadjusted and adjusted probabilities for achievement of minimum clinically relevant improvements of 18 VAS points or 0.25 EQ-5D points were calculated for each surgeon.

RESULTS

Mean preoperative back pain decreased from 69 to 30 points at 1 year (ØΔ 39pts) after TDA, and from 66 to 27 points after ALIF (ØΔ 39pts). Mean preoperative QoL improved from 0.34 to 0.74 points at 1 year (ØΔ 0.40pts). There were surgeons with better patient selection, indicated by lower adjusted probabilities reflecting worsening of outcomes if they had treated an average patient sample. ALIF had similar pain alleviation than TDA.

CONCLUSIONS

Pain alleviation after TDA and ALIF was similar. Differences in surgeon's patient selection based on pain and QoL were revealed. Some surgeons seem to miss the full therapeutic potential of TDA by selecting patients with lower symptom severity.

Benchmarking in the SWISSspine registry: results of 52 Dynardi lumbar total disc replacements compared with the data pool of 431 other lumbar disc prostheses

The SWISSspine registry is the first mandatory registry of its kind in the history of Swiss orthopaedics and it follows the principle of "coverage with evidence development". Its goal is the generation of evidence for a decision by the Swiss federal office of health about reimbursement of the concerned technologies and treatments by the basic health insurance of Switzerland. Recently, developed and clinically implemented, the Dynardi total disc arthroplasty (TDA) accounted for 10% of the implanted lumbar TDAs in the registry. We compared the outcomes of patients treated with Dynardi to those of the recipients of the other TDAs in the registry. Between March 2005 and October 2009, 483 patients with single-level TDA were documented in the registry. The 52 patients with a single Dynardi lumbar disc prosthesis implanted by two surgeons (CE and OS) were compared to the 431 patients who received one of the other prostheses. Data were collected in a prospective, observational multicenter mode. Surgery, implant, 3-month, 1-year, and 2-year follow-up forms as well as comorbidity, NASS and EQ-5D questionnaires were collected. For statistical analyses, the Wilcoxon signed-rank test and chi-square test were used. Multivariate regression analyses were also performed. Significant and clinically relevant reduction of low back pain and leg pain as well as improvement in quality of life was seen in both groups (P < 0.001 postop vs. preop). There were no inter-group differences regarding postoperative pain levels, intraoperative and follow-up complications or revision procedures with a new hospitalization. However, significantly more Dynardi patients achieved a minimum clinically relevant low back pain alleviation of 18 VAS points and a quality of life improvement of 0.25 EQ-5D points. The patients with Dynardi prosthesis showed a similar outcome to patients receiving the other TDAs in terms of postoperative low back and leg pain, complications, and revision procedures. A higher likelihood for achieving a minimum clinically relevant improvement of low back pain and quality of life in Dynardi patients was observed. This difference might be due to the large number of surgeons using other TDAs compared to only two surgeons using the Dynardi TDA, with corresponding variations in patient selection, patient-physician interaction and other factors, which cannot be assessed in a registry study.