Advanced meta-analyses comparing the three surgical techniques total disc replacement, anterior stand-alone fusion and circumferential fusion regarding pain, function and complications up to 3 years to treat lumbar degenerative disc disease

Lumbar Total Disk Replacement Device Removals and Revisions Performed During a 20-Year Experience with 2141 Patients

STUDY DESIGN

This was a retrospective study with prospective patient contact attempted to collect current data.

OBJECTIVE

The purpose was to investigate the incidence and reasons for lumbar total disk replacement (TDR) removal or revision.

SUMMARY OF BACKGROUND DATA

A concern regarding lumbar TDR was safety, particularly the need for device removal or revision. This may be particularly important considering removal/revision requires repeat anterior exposure with an increased risk of vascular injury.

METHODS

Data were collected for a series of 2141 lumbar TDR patients, beginning with the first case experience in 2000. The mean follow-up was 78.6 months. For each case of device removal/revision, the reason, duration from index surgery, and procedure performed were recorded.

RESULTS

Of 2141 patients, 27 (1.26%) underwent TDR removal or revision. Device removal was performed in 24 patients (1.12%), while three patients underwent revision (0.14%). Of the 24 removals, 12 were due to migration and/or loosening, three developed problems post-trauma, two developed lymphocytic reaction to device materials, two had ongoing pain, and there was one case of each: TDR was too large, vertebral body fracture (osteoporosis), lytic lesion, device subsidence and facet arthrosis, and infection seeded from a chest infection 146 months post-TDR. The three revisions were for Core repositioning (technique error), device repositioning after displacement, and core replacement due to wear/failure. With respect to timing, 37.0% of removals/revisions occurred within one-month postimplantation. Of note, 40.7% of removals/revisions occurred in the first 25 TDR cases performed by individual surgeons. There was one significant vascular complication occurring in a patient whose TDR was removed due to trauma. This was also the only patient among 258 with ≥15-year follow-up who underwent removal/revision.

CONCLUSION

In this large consecutive series, 1.26% of TDRs were removed/revised. The low rate over a 20 year period supports the safety of these devices.

Lumbar Disc Replacement Versus Interbody Fusion: Meta-analysis of Complications and Clinical Outcomes

Background

Lumbar spinal fusion is a commonly performed operation with relatively high complication and revision surgery rates. Lumbar disc replacement is less commonly performed but may have some benefits over spinal fusion. This meta-analysis aims to compare the outcomes of lumbar disc replacement (LDR) versus interbody fusion (IBF), assessing their comparative safety and effectiveness in treating lumbar DDD.

Methods

PubMed, Cochrane, and Google Scholar (pages 1-2) were searched up until February 2024. The studied outcomes included operative room (OR) time, estimated blood loss (EBL), length of hospital stay (LOS), complications, reoperations, Oswestry Disability Index (ODI), back pain, and leg pain.

Results

Ten studies were included in this meta-analysis, of which six were randomized controlled trials, three were retrospective studies, and one was a prospective study. A total of 1720 patients were included, with 1034 undergoing LDR and 686 undergoing IBF. No statistically significant differences were observed in OR time, EBL, or LOS between the LDR and IBF groups. The analysis also showed no significant differences in the rates of complications, reoperations, and leg pain between the two groups. However, the LDR group demonstrated a statistically significant reduction in mean back pain (p=0.04) compared to the IBF group.

Conclusion

Both LDR and IBF procedures offer similar results in managing CLBP, considering OR time, EBL, LOS, complication rates, reoperations, and leg pain, with slight superiority of back pain improvement in LDR. This study supports the use of both procedures in managing degenerative spinal disease.

Primary anterior lumbar interbody fusion, with and without posterior instrumentation: a 1,377-patient cohort from a multicenter spine registry

BACKGROUND CONTEXT

Lumbar interbody instrumentation techniques are common and effective surgical options for a variety of lumbar degenerative pathologies. Anterior lumbar interbody fusion (ALIF) has become a versatile and powerful means of decompression, stabilization, and reconstruction. As an anterior only technique, the integrity of the posterior muscle and ligaments remain intact. Adding posterior instrumentation to ALIF is common and may confer benefits in terms of higher fusion rate but could contribute to adjacent segment degeneration due to additional rigidity. Large clinical studies comparing stand-alone ALIF with and without posterior supplementary fixation (ALIF+PSF) are lacking.

PURPOSE

To compare rates of operative nonunion and adjacent segment disease (ASD) in ALIF with or without posterior instrumentation.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Adult patients (≥18 years old) who underwent primary ALIF for lumbar degenerative pathology between levels L4 to S1 over a 12-year period. Exclusion criteria included trauma, cancer, infection, supplemental decompression, noncontiguous fusions, prior lumbar fusions, and other interbody devices.

OUTCOME MEASURES

Reoperation for nonunion and ASD compared between ALIF only and ALIF+PSF.

METHODS

Reoperations were modeled as time-to-events where the follow-up time was defined as the difference between the primary ALIF procedure and the date of the outcome of interest. Crude cumulative reoperation probabilities were reported at 5-years follow-up. Multivariable Cox proportional hazard regression was used to evaluate risk of operative nonunion and for ASD adjusting for patient characteristics.

RESULTS

The study consisted of 1,377 cases; 307 ALIF only and 1070 ALIF+PSF. Mean follow-up time was 5.6 years. The 5-year crude nonunion incidence was 2.4% for ALIF only and 0.5% for ALIF+PSF; after adjustment for covariates, a lower operative nonunion risk was observed for ALIF+PSF (HR=0.22, 95% CI=0.06-0.76). Of the patients who are deemed potentially suitable for ALIF alone, one would need to add posterior instrumentation in 53 patients to prevent one case of operative nonunion at a 5-year follow-up (number needed to treat). Five-year operative ASD incidence was 4.3% for ALIF only and 6.2% for ALIF+PSF; with adjustments, no difference was observed between the cohorts (HR=0.96, 95% CI=0.54-1.71).

CONCLUSIONS

While the addition of posterior instrumentation in ALIFs is associated with lower risk of operative nonunion compared with ALIF alone, operative nonunion is rare in both techniques (<5%). Accordingly, surgeons should evaluate the added risks associated with the addition of posterior instrumentation and reserve the supplemental posterior fixation for patients that might be at higher risk for operative nonunion. Rates of operative ASD were not statistically higher with the addition of posterior instrumentation suggesting concern regarding future risk of ASD perhaps should not play a role in considering supplemental posterior instrumentation in ALIF.

Systematic Review of Platelet-Rich Plasma for Low Back Pain

BACKGROUND

Low back pain (LBP) has a high economic burden and is strongly related to the degenerative process of the spine, especially in the intervertebral disc and of the facet joints. Numerous treatment modalities have been proposed for the management of LBP, and the use of platelet-rich plasma (PRP) has emerged as an innovative therapeutic option for degenerative disease of the spine. The present study aims to evaluate the efficacy of PRP injections in managing low back pain.

METHODS

We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, a registered at PROSPERO Systematic Reviews Platform, under number CRD42021268491. The PubMed, Web of Science, and Scopus databases were searched to identify relevant articles, along with hand searching to identify gray literature articles, with no language restrictions. Randomized clinical trials (RCTs), nonrandomized trials (NRTs), and case series (CSs) with more than 10 patients were considered eligible. The quality assessment and the risk of bias of the randomized clinical trials were evaluated using the RoB II tool. An evaluation of the description of the preparation methods was performed using an adapted version of the MIBO checklist.

RESULTS

An electronic database search resulted in 2324 articles, and after the exclusion of noneligible articles, 13 RCTs and 27 NRTs or CSs were analyzed. Of the 13 RCTs, 11 found favorable results in comparison to the control group in pain and disability, one showed no superiority to the control group, and one was discontinued because of the lack of therapeutic effect at eight-week evaluation. Description of the PRP preparation techniques were found in almost all papers. The overall risk of bias was considered high in 2 papers and low in 11. An adapted MIBO checklist showed a 72.7% compliance rate in the selected areas.

CONCLUSIONS

In this systematic review, we analyzed articles from English, Spanish and Russian language, from large databases and grey literature. PRP was in general an effective and safe treatment for degenerative LPB. Positive results were found in almost studies, a small number of adverse events were related, the risk of bias of the RCTs was low. Based on the evaluation of the included studies, we graded as level II the quality of the evidence supporting the use of PRP in LBP. Large-scale, multicenter RCTs are still needed to confirm these findings.

Correlation between the degree of pain relief following discoblock and short-term surgical disability outcome among patients with suspected discogenic low back pain

OBJECTIVES

To evaluate how well the degree of pain relief after discoblock predicts the disability outcome of subsequent fusion or total disc replacement (TDR) surgery, based on short-term Oswestry Disability Index (ODI) scores.

METHODS

We retrospectively analyzed a set of patients who had undergone discoblock and subsequent fusion or TDR surgery of the same lumbar intervertebral disc due to suspected discogenic chronic LBP between 2011 and 2018. We calculated the degree of pain relief following discoblock (ΔNRS) and the changes in both absolute and percentual ODI scores (ΔODI and ΔODI%, respectively) following fusion or TDR surgery. We analyzed the statistical significance of ΔNRS and ΔODI and the correlation (Spearman's rho) between ΔNRS and ΔODI%. The fusion and TDR group were analyzed both in combination and separately.

RESULTS

Fifteen patients were eligible for the current study (fusion n=9, TDR n=6). ΔNRS was statistically significant in all groups, and ΔODI was statistically significant in the combined group and in the fusion group alone. The parameters of both decreased. We found a Spearman's rho of 0.57 (p=0.026) between ΔNRS and ΔODI% for the combined group. The individual Spearman's rho values were 0.85 (p=0.004) for the fusion group and 0.62 (p=0.191) for the TDR group.

CONCLUSIONS

We suggest that discoblock is a useful predictive criterion for disability outcome prior to surgery for discogenic LBP, especially when stabilizing spine surgery is under consideration.

ETHICAL COMMITTEE NUMBER

174/2019 (Oulu University Hospital Ethics Committee).

Intervertebral disc repair and regeneration: Insights from the notochord

The vertebrate notochord plays an essential role in patterning multiple structures during embryonic development. In the early 2000s, descendants of notochord cells were demonstrated to form the entire nucleus pulposus of the intervertebral disc in addition to their key role in embryonic patterning. The nucleus pulposus undergoes degeneration during postnatal life, which can lead to back pain. Recently, gene and protein profiles of notochord and nucleus pulposus cells have been identified. These datasets, coupled with the ability to differentiate human induced pluripotent stem cells (iPSCs) into cells that resemble nucleus pulposus cells, provide the possibility of generating a cell-based therapy to halt and/or reverse disc degeneration.