Total disc replacement surgery for symptomatic degenerative lumbar disc disease: a systematic review of the literature

The objective of this study is to evaluate the effectiveness and safety of total disc replacement surgery compared with spinal fusion in patients with symptomatic lumbar disc degeneration. Low back pain (LBP), a major health problem in Western countries, can be caused by a variety of pathologies, one of which is degenerative disc disease (DDD). When conservative treatment fails, surgery might be considered. For a long time, lumbar fusion has been the “gold standard” of surgical treatment for DDD. Total disc replacement (TDR) has increased in popularity as an alternative for lumbar fusion. A comprehensive systematic literature search was performed up to October 2008. Two reviewers independently checked all retrieved titles and abstracts, and relevant full text articles for inclusion. Two reviewers independently assessed the risk of bias of included studies and extracted relevant data and outcomes. Three randomized controlled trials and 16 prospective cohort studies were identified. In all three trials, the total disc replacement was compared with lumbar fusion techniques. The Charité trial (designed as a non-inferiority trail) was considered to have a low risk of bias for the 2-year follow up, but a high risk of bias for the 5-year follow up. The Charité artificial disc was non-inferior to the BAK^® Interbody Fusion System on a composite outcome of “clinical success” (57.1 vs. 46.5%, for the 2-year follow up; 57.8 vs. 51.2% for the 5-year follow up). There were no statistically significant differences in mean pain and physical function scores. The Prodisc artificial disc (also designed as a non-inferiority trail) was found to be statistically significant more effective when compared with the lumbar circumferential fusion on the composite outcome of “clinical success” (53.4 vs. 40.8%), but the risk of bias of this study was high. Moreover, there were no statistically significant differences in mean pain and physical function scores. The Flexicore trial, with a high risk of bias, found no clinical relevant differences on pain and physical function when compared with circumferential spinal fusion at 2-year follow up. Because these are preliminary results, in addition to the high risk of bias, no conclusions can be drawn based on this study. In general, these results suggest that no clinical relevant differences between the total disc replacement and fusion techniques. The overall success rates in both treatment groups were small. Complications related to the surgical approach ranged from 2.1 to 18.7%, prosthesis related complications from 2.0 to 39.3%, treatment related complications from 1.9 to 62.0% and general complications from 1.0 to 14.0%. Reoperation at the index level was reported in 1.0 to 28.6% of the patients. In the three trials published, overall complication rates ranged from 7.3 to 29.1% in the TDR group and from 6.3 to 50.2% in the fusion group. The overall reoperation rate at index-level ranged from 3.7 to 11.4% in the TDR group and from 5.4 to 26.1% in the fusion group. In conclusion, there is low quality evidence that the Charité is non-inferior to the BAK cage at the 2-year follow up on the primary outcome measures. For the 5-year follow up, the same conclusion is supported only by very low quality evidence. For the ProDisc, there is very low quality evidence for contradictory results on the primary outcome measures when compared with anterior lumbar circumferential fusion. High quality randomized controlled trials with relevant control group and long-term follow-up is needed to evaluate the effectiveness and safety of TDR.     

Comparison of artificial total disc replacement versus fusion for lumbar degenerative disc disease: a meta-analysis of randomized controlled trials

Purpose

To compare the efficacy and safety of TDR to that of the fusion for the treatment of lumbar degenerative disc disease (LDDD).

Methods

Randomized controlled trials comparing TDR with any other intervention for LDDD were acquired by a comprehensive search in PubMedCentral, MEDLINE, EMBASE, BIOSIS, ClinicalTrials.gov, and the FDA trials register. Methodologic quality was assessed and relevant data were retrieved, and appropriate meta-analysis was performed. Two review authors independently selected studies, extracted data, and assessed risk of bias. Results and upper bounds of confidence intervals were compared with predefined clinically relevant differences.

Results

Six relevant randomized controlled trials (RCTs) involving 1,603 patients were identified and reported two year follow-up results. Patients in TDR group compared with lumbar fusion group demonstrated significant improvements in ODI, VAS scores and complication rates at the two year follow-up. Meanwhile, except for operating time in anterior group, intra-operative blood loss, operating time in posterior group, and reoperation rate were without clinical significance between the two groups. In addition, the range of motion (ROM) was maintained within normal ranges after TDR.

Conclusions

The results showed the TDR has significant safety and efficacy comparable to lumbar fusion at two year follow-up. Although superiority compared to fusion could not be proved, by comparing clinical symptoms relieved, motion preserved, and the low reoperation rate during long-term follow-up on TDR, TDR was considered safe and effective. Therefore, the authors suggest adopting TDR on a large scale; with failure of TDR, interbody fusion would be performed.     

Charité total disc replacement—clinical and radiographical results after an average follow-up of 17 years

A retrospective clinical–radiological study to evaluate the long-term outcome after artificial disc replacement was performed. The objective is to investigate long-term results after implantation of a modular type artificial disc prosthesis in patients with degenerative disc disease (DDD). Total disc replacement (TDR) is a surgical procedure intended to save segmental spinal function, and thus replace spondylodesis. Short-term results are promising, whereas long-term results are scarce. The Charité TDR is the oldest existing implant, therefore, the longest possible follow-up is presented here. Seventy-one patients were treated with 84 Charité TDRs types I–III. Indication for TDR was moderate to severe DDD. Fifty-three patients (63 TDRs) were available for long-term follow-up of 17 years. Evaluation included Oswestry disability index, visual analog scale, overall outcome score, plain and extension/flexion radiographs. Implantation of Charité TDR resulted in a 60% rate of spontaneous ankylosis after 17 years. No significant difference between the three types of prostheses was found concerning clinical outcome. Reoperation was necessary in 11% of patients. Although no adjacent segment degeneration was observed in the functional implants (17%), these patients were significantly less satisfied than those with spontaneous ankylosis. TDR, nowadays, is an approved procedure. Proof that long-term results of TDR implantation in DDD are at least as good as fusion results is still missing.     

The current status of lumbar total disc replacement

Total disc replacement is an exciting technology that may one day replace fusion as the gold standard treatment for DDD, but it is currently an experimental procedure in the United States. Promising short- and mid-term results have been reported for TDR, but longer follow-up and randomized trials comparing TDR to fusion and nonsurgical treatment are needed to fully define the role of TDR in the spine surgeon's armamentarium. Short-term complication rates have been acceptably low, but in the long term the durability of TDR implants and the vertebral endplate will provide challenges. Finally, it is essential that practitioners understand that a limited subset of patients are good candidates for TDR and that indiscriminate application of this technology will result in poor outcomes.     

Artificial total disc replacement versus fusion for lumbar degenerative disc disease: a meta-analysis of randomized controlled trials

Objective

The purpose of this study is to compare the effectiveness and safety of artificial total disc replacement (TDR) with fusion for the treatment of lumbar degenerative disc disease (DDD).

Summary of background data

Spinal fusion is the conventional surgical treatment for lumbar DDD. Recently, TDR has been developed to avoid the negative effects of the fusion by preserving function of the motion segment. Controversy still surrounds regarding whether TDR is better.

Methods

We systematically searched six electronic databases (Medline, Embase, Clinical, Ovid, BIOSIS and Cochrane registry of controlled clinical trials) to identify randomized controlled trials (RCTs) published up to March 2013 in which TDR was compared with the fusion for the treatment of lumbar DDD. Effective data were extracted after the assessment of methodological quality of the trials. Then, we performed the meta-analysis.

Results

Seven relevant RCTs with a total of 1,584 patients were included. TDR was more effective in ODI (MD ?5.09; 95 % CI [?7.33, ?2.84]; P < 0.00001), VAS score (MD ?5.31; 95 % CI [?8.35, ?2.28]; P = 0.0006), shorter duration of hospitalization (MD ?0.82; 95 % CI [?1.38, ?0.26]; P = 0.004) and a greater proportion of willing to choose the same operation again (OR 2.32; 95 % CI [1.69, 3.20]; P < 0.00001). There were no significant differences between the two treatment methods regarding operating time (MD ?44.16; 95 % CI [?94.84, 6.52]; P = 0.09), blood loss (MD ?29.14; 95 % CI [?173.22, 114.94]; P = 0.69), complications (OR 0.72; 95 % CI [0.45, 1.14]; P = 0.16), reoperation rate (OR 0.83; 95 % CI [0.39, 1.77]; P = 0.63) and the proportion of patients who returned to full-time/part-time work (OR 1.10; 95 % CI [0.86, 1.41]; P = 0.47).

Conclusion

TDR showed significant safety and efficacy comparable to lumbar fusion at 2 year follow-up. TDR demonstrated superiorities in improved physical function, reduced pain and shortened duration of hospitalization. The benefits of operating time, blood loss, motion preservation and the long-term complications are still unable to be proved.     

Mid- to long-term results of total disc replacement for lumbar degenerative disc disease: a systematic review

Background

Lumbar total disc replacement (TDR) has shown satisfactory clinical outcomes with few complications and reoperations at short-term follow-up, but the mid- to long-term results are not clear.

Purpose

The objective of this study was to evaluate the mid- to long-term clinical outcomes of artificial TDR for lumbar degenerative disc diseases.

Patients and methods

A systematic search was conducted using the PubMed database to identify studies of TDR surgery that included at least 3?years of follow-up. The search keywords were as follows: lumbar, total disc replacement, and arthroplasty. The following data were extracted: patient demographics, visual analogue scale (VAS) and Oswestry disability index (ODI) scores, satisfactory rate, clinical success rate, complications, and reoperations.

Results

Thirteen studies, including eight prospective studies and five retrospective studies, met the criteria. A total of 946 patients were identified who reported at least 3?years of follow-up results. The artificial prostheses in these studies were ProDisc-L, Charité, AcroFlex, Maverick, and XL TDR. Patients with lumbar TDR demonstrated significant improvements in VAS scores of 51.1 to 70.5% and of ??15.6 to ??44.4 for Oswestry disability index (ODI) scores at the last follow-up. Patient satisfaction rates were reported in eight studies and ranged from 75.5 to 93.3%. Complication rates were reported in 11 studies, ranging from 0 to 34.4%. The overall reoperation rate was 12.1% (119/986), ranging from 0 to 39.3%, with eight of the 13 studies reporting a reoperation rate of less than 10%.

Conclusions

This review shows that lumbar TDR effectively results in pain relief and an improvement in quality of life at mid- to long-term follow-up. Complication and reoperation rates were acceptable. However, this study did not provide sufficient evidence to show that lumbar TDR is superior to fusion surgery. To answer that question, a greater number of high-quality randomized controlled trials (RCTs) are needed.

     

Five-year follow-up of total disc replacement compared to fusion: a randomized controlled trial

Purpose

To evaluate long-term clinical results of lumbar total disc replacement (TDR) compared with posterior lumbar fusion.

Methods

This prospective randomized controlled trial comprised 152 patients; 80 were randomized to TDR and 72 to fusion. All patients had chronic low back pain (CLBP) and had not responded to nonsurgical treatment. Primary outcome measure was global assessment of back pain (GA), secondary outcome measures were back and leg pain, Oswestry Disability Index (ODI), EQ5D, and SF-36. All measures were collected from SweSpine (Swedish national register for spinal surgery) at 1, 2, and 5 years. Follow-up rate at 5 years was 99.3 %.

Results

Both groups showed clinical improvement at 5-year follow-up. For GA, 38 % (30/80) in the TDR group were totally pain free vs. 15 % (11/71) in the fusion group (p < 0.003). Back pain and improvement of back pain were better in the TDR group: VAS back pain at 5 years 23 ± 29 vs. 31 ± 27, p = 0.009, and VAS improvement of back pain at 5 years 40 ± 32 vs. 28 ± 32, p = 0.022. ODI and improvement in ODI were also better in the TDR group: ODI at 5 years 17 ± 19 vs. 23 + 17, p = 0.02 and ODI improvement at 5 years 25 ± 18 vs. 18 ± 19 (p = 0.02). There was no difference in complications and reoperations between the two groups.

Conclusions

Global assessment of low back pain differed between the two surgical groups at all follow-up occasions. Significant differences between groups concerning back pain, pain improvement, and ODI were present at 1 year and disappeared at 2 years, but reappeared at the 5-year follow-up.     

Mid- to long-term results of total lumbar disc replacement: a prospective analysis with 5- to 10-year follow-up

Background contextThe role of fusion of lumbar motion segments for the treatment of intractable low back pain (LBP) from degenerative disc disease (DDD) without deformities or instabilities remains controversially debated. Total lumbar disc replacement (TDR) has been used as an alternative in a highly selected patient cohort. However, the amount of long-term follow-up (FU) data on TDR is limited. In the United States, insurers have refused to reimburse surgeons for TDRs for fear of delayed complications, revisions, and unknown secondary costs, leading to a drastic decline in TDR numbers.PurposeTo assess the mid- and long-term clinical efficacy as well as patient safety of TDR in terms of perioperative complication and reoperation rates.Study design/settingProspective, single-center clinical investigation of TDR with ProDisc II (Synthes, Paoli, PA, USA) for the treatment of LBP from lumbar DDD that has proven unresponsive to conservative therapy.Patient samplePatients with a minimum of 5-year FU after TDR, performed for the treatment of intractable and predominant (≥80%) axial LBP resulting from DDD without any deformities or instabilities.Outcome measuresVisual analog scale (VAS), Oswestry Disability Index (ODI), and patient satisfaction rates (three-scale outcome rating); complication and reoperation rates as well as elapsed time until revision surgery; patient's professional activity/employment status.MethodsClinical outcome scores were acquired within the framework of an ongoing prospective clinical trial. Patients were examined preoperatively, 3, 6, and 12 months postoperatively, annually from then onward. The data acquisition was performed by members of the clinic's spine unit including medical staff, research assistants, and research nurses who were not involved in the process of pre- or postoperative decision-making.ResultsThe initial cohort consisted of 201 patients; 181 patients were available for final FU, resembling a 90.0% FU rate after a mean FU of 7.4 years (range 5.0–10.8 years). The overall results revealed a highly significant improvement from baseline VAS and ODI levels at all postoperative FU stages (p<.0001). VAS scores demonstrated a slight (from VAS 2.6 to 3.3) but statistically significant deterioration from 48 months onward (p<.05). Patient satisfaction rates remained stable throughout the entire postoperative course, with 63.6% of patients reporting a highly satisfactory or a satisfactory (22.7%) outcome, whereas 13.7% of patients were not satisfied. The overall complication rate was 14.4% (N=26/181). The incidence of revision surgeries for general and/or device-related complications was 7.2% (N=13/181). Two-level TDRs demonstrated a significant improvement of VAS and ODI scores in comparison to baseline levels (p<.05). Nevertheless, the results were significantly inferior in comparison to one-level cases and were associated with higher complication (11.9% vs. 27.6%; p=.03) and inferior satisfaction rates (p<.003).ConclusionsDespite the fact that the current data comprises the early experiences and learning curve associated with a new surgical technique, the results demonstrate satisfactory and maintained mid- to long-term clinical results after a mean FU of 7.4 years. Patient safety was proven with acceptable complication and reoperation rates. Fear of excessive late complications or reoperations following the primary TDR procedure cannot be substantiated with the present data. In carefully selected cases, TDR can be considered a viable treatment alternative to lumbar fusion for which spine communities around the world seem to have accepted mediocre clinical results as well as obvious and significant drawbacks.     

Hybrid construct for two levels disc disease in lumbar spine

Prospective study. To study the validity of Hybrid construction (Anterior Lumbar Interbody Fusion) ALIF at one level and total disc arthroplasty (TDA) at adjacent, for two levels disc disease in lumbar spine as surgical strategy. With growing evidence that fusion constructs in the treatment of degenerative disc disease (DDD) may alter sagittal balance and contribute to undesirable complications in the long-term, total disc arthroplasty (TDA) slowly becomes an accepted treatment option for a selected group of patients. Despite encouraging early and intermediate term results of single-level total disc arthroplasty reported in the literature, there is growing evidence that two-level arthroplasty does not fare as well. Hybrid fusion is an attempt to address two-level DDD by combining the advantages of a single-level ALIF with those of a single-level arthroplasty. 42 patients (25 females and 17 males) underwent Hybrid fusion and had a median follow-up of 26.3 months. The primary functional outcomes were assessed before and after surgery with Oswestry Disability Index and the visual analogue score of the back and legs. Patients were divided into four groups according to the percentage improvement between preop and postop ODI scores. A total of 42 patients underwent a hybrid fusion as follows: 35 L5-S1 ALIF/L4-5 prosthesis, 3 L4-5 ALIF/L3-4 prosthesis, 2 L5-S1 ALIF/L4-5 prosthesis/L3-4 prosthesis, 1 L5-S1 prosthesis/L4-5 ALIF, and 1 L5-S1 ALIF/L4-5 ALIF/L3-4 prosthesis. At 2-years clinical outcomes, mean reduction in ODI is 24.9 points (53.0% improvement compared to preop ODI). The visual analogue score for the back is 64.6% improvement. At 2-year clinical outcomes, Hybrid fusion is a viable surgical alternative for the treatment of two-level DDD in comparison with two-level TDA and with two-level fusion.     

Influence of lumbar intervertebral disc degeneration on the outcome of total lumbar disc replacement: a prospective clinical, histological, X-ray and MRI investigation

Introduction

The role of fusion of lumbar motion segments for the treatment of axial low back pain (LBP) from lumbar degenerative disc disease (DDD) without any true deformities or instabilities remains controversially debated. In an attempt to avoid previously published and fusion-related negative side effects, motion preserving technologies such as total lumbar disc replacement (TDR) have been introduced. The adequate extent of preoperative DDD for TDR remains unknown, the number of previously published studies is scarce and the limited data available reveal contradictory results. The goal of this current analysis was to perform a prospective histological, X-ray and MRI investigation of the index-segment’s degree of DDD and to correlate these data with each patient’s pre- and postoperative clinical outcome parameters from an ongoing prospective clinical trial with ProDisc II (Synthes, Paoli, USA).

Materials and methods

Nucleus pulposus (NP) and annulus fibrosus (AF) changes were evaluated according to a previously validated quantitative histological degeneration score (HDS). X-ray evaluation included assessment of the mean, anterior and posterior disc space height (DSH). MRI investigation of DDD was performed on a 5-scale grading system. The prospective clinical outcome assessment included Visual Analogue Scale (VAS), Oswestry Disability Index (ODI) scores as well as the patient’s subjective satisfaction rates.

Results

Data from 51 patients with an average follow-up of 50.5 months (range 6.1–91.9 months) were included in the study. Postoperative VAS and ODI scores improved significantly in comparison to preoperative levels (p < 0.002). A significant correlation and interdependence was established between various parameters of DDD preoperatively (p < 0.05). Degenerative changes of NP tissue samples were significantly more pronounced in comparison to those of AF material (p < 0.001) with no significant correlation between each other (p > 0.05). Preoperatively, the extent of DDD was not significantly correlated with the patient’s symptomatology (p > 0.05). No negative influence was associated with increasing stages of DDD on the postoperative clinical outcome parameters following TDR (p > 0.05). Increasing stages of DDD in terms of lower DSH scores were not associated with inferior clinical results as outlined by postoperative VAS or ODI scores or the patient’s subjective outcome evaluation at the last FU examination (p > 0.05). Conversely, some potential positive effects on the postoperative outcome were observed in patients with advanced stages of preoperative DDD. Patients with more severe preoperative HDS scores of NP samples demonstrated significantly lower VAS scores during the early postoperative course (p = 0.02).

Conclusion

Increasing stages of DDD did not negatively impact on the outcome following TDR in a highly selected patient population. In particular, no preoperative DDD threshold value was identified from which an inferior postoperative outcome could have been deduced. Conversely, some positive effects on the postoperative outcome were detected in patients with advanced stages of DDD. Combined advantageous effects of progressive morphological structural rigidity of the index segment and restabilizing effects from larger distraction in degenerated segments may compensate for increasing axial rotational instability, one of TDR’s perceived disadvantages. Our data reveal a “therapeutic window” for TDR in a cohort of patients with various stages of DDD as long as preoperative facet joint complaints or degenerative facet arthropathies can be excluded and stringent preoperative decision making criteria are adhered to. Previously published absolute DSH values as contraindication against TDR should be reconsidered.     

Anterior discectomy and total disc replacement for three patients with multiple recurrent lumbar disc herniations

Background context

Although results of primary discectomy are generally excellent with relief of leg pain, recurrent lumbar disc herniation is relatively common ranging from 5% to 25%. Patients with recurrent herniation may undergo revision surgery; however, this carries with it increased risks and lower success rates. Many surgeons will advocate a fusion in addition to repeat discectomy after the third recurrent herniated disc. With the approval of lumbar total disc arthroplasty, there now exists another option for the patient with three or more recurrent disc herniations to preserve motion, theoretically decrease the rate of adjacent-level disease, and ameliorate the patient’s symptoms.

Purpose

The purpose of this case report is to describe our experience using total disc replacement (TDR) in three patients after prior partial hemilaminectomy and discectomy for the treatment of a third and fourth recurrent lumbar disc herniation.

Study design

This article is a report of three cases from a spine specialty center describing an alternative surgical technique for patients with multiple recurrent lumbar disc herniation.

Methods

Comprehensive chart review of three patients with recurrent lumbar herniation who underwent TDR.

Results

Anterior discectomy and TDR were undertaken, and at most recent follow-up (8–12 months), all patients had improvement of their visual analog scale and Oswestry Disability Index. No patient had postoperative complications or reoperation.

Conclusions

Recurrent disc herniation is a relatively common problem that may be difficult to treat. Traditionally, a patient presenting with three or more recurrent disc herniation may likely have undergone revision discectomy with fusion. The current case report suggests that TDR may be an alternative option in select patients.     

Sex life and sexual function in men and women before and after total disc replacement compared with posterior lumbar fusion

Background contextSex life and sexual function may be affected by low back pain (LBP). Sexual dysfunction after anterior lumbar fusion is reported in both men and women, but focus is mainly on impaired male biological function (retrograde ejaculation) as this may cause infertility. This has led to concern as to whether anterior surgery should be employed in men, at least in younger age groups.PurposeTo investigate how chronic low back pain (CLBP) of assumed discogenic origin affects sex life and sexual function in patients considered for surgical treatment, whether this is affected by surgical treatment (total disc replacement [TDR] or posterolateral fusion [PLF]/posterior lumbar interbody fusion [PLIF]), and if so, are there differences between the surgical procedures undertaken.Study designA randomized controlled trial comparing TDR and instrumented lumbar spine fusion, performed either as a PLF or PLIF.Patient sampleOne hundred fifty-two patients were included in this randomized controlled trial to compare the effect on CLBP of either TDR via an anterior retroperitoneal approach or instrumented posterior lumbar fusion, PLF or PLIF.Outcome measuresGlobal assessment of back pain, back pain (visual analog scale [VAS] 0-100), function (Oswestry Disability Index [ODI] 0–100), quality of life (EQ5D [EuroQol] 0–1), and answers on specific sexual function.MethodsOutcome was assessed using data from the Swedish Spine Register (SweSpine). In ODI, one question, ODI 8, reflects the impact of back pain on sex life. This question was analyzed separately. Patients also answered a gender-specific questionnaire preoperatively and at the 2-year follow-up to determine any sexual dysfunction regarding erection, orgasm, and ejaculation. Follow-up was at 1 and 2 years.ResultsBefore surgery, 34% reported that their sex life caused some extra LBP, and an additional 30% that their sex life was severely restricted by LBP. After surgery, sex life improved in both groups, with a strong correlation to a reduction of LBP. The gender-specific questionnaire used to measure sexual function after 2 years revealed no negative effect of TDR or Fusion in men regarding erection or retrograde ejaculation. However, 26% of all men in the Fusion group, compared with 3% in the TDR group, reported postoperative deterioration in the ability to achieve orgasm, despite a reduction of LBP.ConclusionsImpairment of sex life appears to be related to CLBP. An improvement in sex life after TDR or lumbar fusion was positively correlated to a reduction in LBP. Total disc replacement in this study, performed through an anterior retroperitoneal approach, was not associated with greater sexual dysfunction compared with instrumented lumbar fusion performed either as a PLF or as a PLIF. Sexual function, expressed as orgasm, deteriorated in men in the Fusion group postoperatively, in spite of this group reporting less LBP after 2 years.     

Transforaminal endoscopic surgery for symptomatic lumbar disc herniations: a systematic review of the literature

The study design includes a systematic literature review. The objective of the study was to evaluate the effectiveness of transforaminal endoscopic surgery and to compare this with open microdiscectomy in patients with symptomatic lumbar disc herniations. Transforaminal endoscopic techniques for patients with symptomatic lumbar disc herniations have become increasingly popular. The literature has not yet been systematically reviewed. A comprehensive systematic literature search of the MEDLINE and EMBASE databases was performed up to May 2008. Two reviewers independently checked all retrieved titles and abstracts and relevant full text articles for inclusion criteria. Included articles were assessed for quality and outcomes were extracted by the two reviewers independently. One randomized controlled trial, 7 non-randomized controlled trials and 31 observational studies were identified. Studies were heterogeneous regarding patient selection, indications, operation techniques, follow-up period and outcome measures and the methodological quality of these studies was poor. The eight trials did not find any statistically significant differences in leg pain reduction between the transforaminal endoscopic surgery group (89%) and the open microdiscectomy group (87%); overall improvement (84 vs. 78%), re-operation rate (6.8 vs. 4.7%) and complication rate (1.5 vs. 1%), respectively. In conclusion, current evidence on the effectiveness of transforaminal endoscopic surgery is poor and does not provide valid information to either support or refute using this type of surgery in patients with symptomatic lumbar disc herniations. High-quality randomized controlled trials with sufficiently large sample sizes are direly needed to evaluate if transforaminal endoscopic surgery is more effective than open microdiscectomy.     

颈椎间盘置换术与颈椎融合术治疗双节段颈椎病疗效比较的Meta分析

目的系统评价颈椎间盘置换术(total disc replacement,TDR)与颈椎融合术治疗双节段颈椎病的疗效与安全性。方法对2004年1月至2014年1月中文科技期刊数据库(VIP)、万方数据库、中国知网、PubMed Central(PMC)、MEDLINE、OVID、Google Scholar数据库中的相关文献进行电子检索及手工检索,纳入TDR(置换组)与颈椎融合术(融合组)治疗双节段颈椎病的随机对照试验(randomized controlled trial,RCT),根据Jadad评分标准评价纳入研究项目的质量。采用Rev Man5.2统计学软件进行Meta分析。结果 8项研究符合纳入标准,共计1 100例患者。Meta分析结果显示,置换组术后2年的患者满意率、颈椎活动度(ROM)、日本骨科协会(Japanese Orthopaedic Association,JOA)评估治疗分数及疼痛视觉模拟评分(visual analogue scale,VAS)均优于融合组,置换组术后2年的再手术率及并发症低于融合组,其余各项指标差异均无统计学意义。结论 TDR治疗双节段颈椎病的疗效与安全性较颈椎融合术有优势,但仍需更多的大样本RCTs进行验证。     

Radiological and clinical long-term results of heterotopic ossification following lumbar total disc replacement

Background

The long-term results of heterotopic ossification (HO) following lumbar total disc replacement (TDR) and the corresponding clinical and radiological outcomes are unclear.

内镜辅助微创入路人工腰椎间盘置换术的临床效果及矢状平衡分析

目的 探讨内镜辅助微创入路人工腰椎间盘置换术的临床效果及对矢状平衡的影响.方法 采用内镜辅助微创入路Maverick人工腰椎间盘置换术治疗腰椎间盘退变性疾病135例.术前MR检查评估小关节和椎旁肌退变程度;术前和随访时均摄腰椎正侧位、过伸过屈位及包括双侧股骨头的站立位脊柱全长正侧位X线片,测量假体位置和活动度、矢状平衡参数.结果 术后随访2～5年,平均3.5年.一个间隙手术时间平均60 min,术中出血平均170 ml.输尿管损伤1例,术中修补后效果好,交感神经损伤5例,术后神经根性痛4例,切口浅表感染1例,保守治疗后均好转.末次随访时Oswestry 评分由术前平均46.6%+12.0%降至23.2%±19.0%;腰痛和腿痛视觉类比评分(visual analogue scale,VAS)分别由术前平均7.6±2.3和3.6±3.0降至2.7±2.5和1.9+2.5.末次随访时间盘置换节段活动度平均7.5°±5.2°,节段性前凸较术前增加,但相邻节段前凸代偿性减少,腰椎前凸轻度增大,维持矢状平衡.L4-5 椎间盘置换同时行L5S1前路融合者L4,5前凸增大不明显;L5S1椎间盘置换者骨盆指数平均降低1.7°;骶骨上终板倾角＜35°者末次随访时平均增大2.1°,＞45°者平均减少3.8°.结论 内镜辅助微创人路Maverick人工腰椎间盘置换术在严格掌握适应证的情况下能取得良好的临床效果,保留椎间活动度,恢复和保持脊柱矢状平衡,间盘置换节段一般前凸增加,但受相邻节段融合手术的影响.     

Total disc replacement versus multidisciplinary rehabilitation in patients with chronic low back pain and degenerative discs: 8-year follow-up of a randomized controlled multicenter trial

Background Context

Lumbar total disc replacement (TDR) is a treatment option for selected patients with chronic low back pain (LBP) that is non-responsive to conservative treatment. The long-term results of disc replacement compared with multidisciplinary rehabilitation (MDR) have not been reported previously.

Clinical outcomes of two revision strategies for failed total disc replacements

PurposeTo compare mid-term clinical outcomes of two revision strategies for patients with failed SB Charité III total disc replacements (TDRs).MethodsEighteen patients with a failed TDR underwent posterolateral instrumented fusion (fusion group); in 21 patients, the TDR was removed and the intervertebral defect was filled with a bone strut graft, followed by an instrumented posterolateral fusion (removal group). Visual analogue scale (VAS) for pain and Oswestry Disability Index (ODI) were completed pre- and post-revision surgery. Intra- and post-operative complications of both revision strategies were assessed.ResultsMean follow-up was 3.7 years (range 1.0–6.4) in the removal group and 4.4 years (range 0.7–11.0) in the fusion group. Although the removal group showed a significantly lower VAS and ODI score post-revision surgery as compared to preoperative (P < 0.01 and P = 0.01, respectively), no significant differences were found between the removal and fusion groups before and after revision surgery in VAS and ODI. A clinical relevant improvement in VAS and ODI was found in 47 and 21 % respectively in the removal group, and in 22 and 27 % respectively in the fusion group. Substantial complications were observed only in the removal group.ConclusionsBoth procedures showed improvement clinically. There were no significant additional benefits of removing the TDR as compared to fusion alone at mid-term follow-up. The clinical decision to remove the TDR should be carefully weighed up against potential risks and complications of this procedure.     

Comparison between single- and multi-level patients: clinical and radiological outcomes 2 years after cervical disc replacement

In cervical multi-level degenerative pathology, considering the morbidity of the extensive fusion techniques, some authors advocate for the multilevel disc replacement. This study compared the safety and efficacy of disc replacement with an unconstrained prosthesis in multi- versus single-level patients. A total of 231 patients with cervical degenerative disc disease (DDD) who were treated with cervical disc replacement and completed their 24 months follow-up were analyzed prospectively: 175 were treated at one level, 56 at 2 levels or more. Comparison between both groups was based on usual clinical and radiological outcomes [Neck Disability Index (NDI), Visual Analog Scale (VAS), Range of Motion, satisfaction]. Safety assessments, including complication and subsequent surgeries, were also documented and compared. Mean NDI and VAS scores for neck and arm pain were improved in both groups similarly. Improvement of mobility at treated segments was also similar. Nevertheless, in the multi-level group, analgesic use was significantly higher and occurrence of Heterotopic Ossification significantly lower than in the single-level group. Subject satisfaction was nearly equal, as 94.2% of single-level group patients would undergo the surgery again versus 94.5% in the multi-level group. The overall success rate did not differ significantly. Multi-level DDD is a challenging indication in the cervical spine. This study showed no major significant clinical difference between the two groups. We need further studies to know more about the impact of multi-level arthroplasty, especially on the adjacent segments, but these results demonstrate initial safety and effectiveness in this patient sample.     

Total disc replacement compared to lumbar fusion: a randomised controlled trial with 2-year follow-up

The study design includes a prospective, randomised controlled study comparing total disc replacement (TDR) with posterior fusion. The main objective of this study is to compare TDR with lumbar spinal fusion, in terms of clinical outcome, in patients referred to a spine clinic for surgical evaluation. Fusion is effective for treating chronic low back pain (LBP), but has drawbacks, such as stiffness and possibly adjacent level degradation. Motion-preserving options have emerged, of which TDR is frequently used because of these drawbacks. How the results of TDR compare to fusion, however, is uncertain. One hundred and fifty-two patients with a mean age of 40 years (21–55) were included: 90 were women, and 80 underwent TDR. The patients had not responded to a conservative treatment programme and suffered from predominantly LBP, with varying degrees of leg pain. Diagnosis was based on clinical examination, radiographs, MRI, and in unclear cases, diagnostic injections. Outcome measures were global assessment (GA), VAS for back and leg pain, Oswestry Disability Index, SF36 and EQ5D at 1 and 2 years. Follow-up rate was 100%, at both 1 and 2 years. All outcome variables improved in both groups between preoperative and follow-up assessment. The primary outcome measure, GA, revealed that 30% in the TDR group and 15% in the fusion group were totally pain-free at 2 years (P = 0.031). TDR patients had reached maximum recovery in virtually all variables at 1 year, with significant differences compared to the fusion group. The fusion patients continued to improve and at 2 years had results similar to TDR patients apart from numbers of pain-free. Complications and reoperations were similar in both groups, but pedicle screw removal as additive surgery, was frequent in the fusion group. One year after surgery, TDR was superior to spinal fusion in clinical outcome, but this difference had diminished by 2 years, apart from (VAS for back pain and) numbers of pain-free. The long-term benefits have yet to be examined.