Opioid analgesic use among patients with kidney disease: a systematic review.

INTRODUCTION: Opioid analgesics are often used to manage moderate to severe pain. A significant proportion of patients taking opioids have compromised kidney function. This systematic review aimed to examine the available evidence on the safety and analgesic effect of opioid use in adults with kidney disease. METHODS: We searched eight electronic databases from inception to 26th January 2023. Published original research articles in English reporting on opioid use and pharmacokinetic data among adults with reduced renal function were included. Article screening, data extraction, and quality assessment were conducted by at least two investigators independently. This review was registered prospectively on PROSPERO (ID: CRD42020159091). RESULTS: There were 32 observational studies included, 14 of which reported on morphine use, three involved fentanyl use, two involved hydromorphone use and 13 articles reported on other opioids including codeine, dihydrocodeine, and buprenorphine. CONCLUSION: There is limited and low-quality evidence to inform the safety and analgesic effect of opioid use in reduced renal function. Morphine remains the opioid for which there is the most evidence available on safety and analgesic effect in the context of renal disease. Greater caution and consideration of potential risks and benefits should be applied when using other opioids. Further high-quality studies examining clinical outcomes associated with the use of different opioids and opioid doses in renal disease are warranted.

Cervical Total Disc Replacement and Heterotopic Ossification: A Review of Literature Outcomes and Biomechanics.

Anterior cervical discectomy and fusion (ACDF) immobilizes surgical segments and can lead to the development of adjacent segment degeneration and adjacent segment disease. Thus, cervical total disc replacement (CTDR) has been developed with the aim to preserve the biomechanics of spine. However, heterotopic ossification (HO), a complication following CTDR, can reduce the segmental range of motion (ROM) and defects the motion-preservation benefit of CTDR. The pathological process of HO in CTDR remains unknown. HO has been suggested to be a self-defense mechanism in response to the non-physiological biomechanics of the cervical spine following CTDR. The current literature review is concerned with the association between the biomechanical factors and HO formation and the clinical significance of HO in CTDR. Endplate coverage, disc height, segmental angle, and center of rotation may be associated with the development of HO. The longer the follow-up, the higher the rate of ROM-limiting HO. Regardless of the loss of motion-preservation benefit of CTDR in patients with HO, CTDR confers patients with a motion-preservation period before the development of ROM-limiting HO. This may delay the development of adjacent segment degeneration compared with ACDF. Future clinical studies should explore the association between HO and changes in biomechanical factors of the cervical spine.

The Changes in Cervical Biomechanics After CTDR and Its Association With Heterotopic Ossification: A Systematic Review and Meta-analysis.

STUDY DESIGN: A systematic review and meta-analysis. OBJECTIVES: Cervical total disc replacement (CTDR) can preserve range of motion (ROM) of the operated spinal segment in cadaver studies. Evidence is less clear in clinical trials. The present study aims to investigate the differences in cervical biomechanics before and after CTDR and its association with heterotopic ossification (HO) development. METHOD: Articles that reported the rate of HO and ≥1 difference in cervical biomechanics were included in quantitative analyses. We pooled the mean difference (MD) of cervical biomechanics before and after CTDR. Subgroup analyses and metaregression analyses were conducted to identify potential contributors to heterogeneity. RESULTS: Of the 599 studies screened, 35 studies were included in the final analysis. In comparison with preoperative values, ROM of the spinal segment inferior (MD: 0.38; 95% CI: 0.02 to 0.74) and superior (MD: 0.43; 95% CI: 0.12 to 0.75) to the surgical spinal segment, functional spinal unit (FSU) angle (MD: 2.23; 95% CI: 1.11 to 3.35), and C2/C7 Cobb angle (MD: 3.49; 95% CI: 1.73 to 5.25) significantly increased after CTDR. In contrast, FSU and cervical ROM at baseline were no different from follow-up. On multivariable meta-regression analyses, HO and ROM-limiting HO were not associated with changes in cervical biomechanics. Single-level CTDR and duration of follow-up were associated with changes in cervical biomechanics. CONCLUSION: Our study reported the pooled mean of biomechanics at baseline and final follow-up and their differences. The changes in biomechanics were not associated with the rates of HO and ROM-limiting HO.

Prevalence of and Risk Factors for Heterotopic Ossification After Cervical Total Disc Replacement: A Systematic Review and Meta-Analysis.

STUDY DESIGN: A systematic review and meta-analysis. OBJECTIVES: The results from previous meta-analyses are limited by the small number of included studies. Moreover, the risk factors of heterotopic ossification (HO) have not been well studied. Therefore, this study aims to estimate the prevalence of HO after cervical total disc replacement (CTDR) at different follow-up time points and explore potential risk factors for HO. METHODS: We searched databases to identify eligible studies that reported the rate of HO after CTDR. The pooled prevalence of HO, according to different grades of HO, length of follow-up and types of prosthesis, and 95% confidence intervals (CIs) were calculated. Multivariable meta-regression analyses were performed to identify factors that may contribute to the heterogeneity between estimates. RESULTS: Of the 94 studies included, 82 studies reported an overall rate of HO, encompassing a total of 5861 cervical spinal levels that underwent CTDR. The overall pooled prevalence of HO was 32.5% (95% CI 26.7% to 38.4%). Single-level CTDR was associated with a higher overall rate of HO. When the rate of HO was stratified by McAfee/Mehren classification, the pooled prevalence of range of motion (ROM)-limiting HO was 11.0% (95% CI 9.2% to 12.8%). Latest publication, single-level CTDR, longer follow-up period, and studies published outside were associated with a higher rate of ROM-limiting HO. CONCLUSIONS: We provide a comprehensive overview of the prevalence of different grades of HO. This meta-analysis also identifies and rules out some risk factors for HO after CTDR.

Comparison of M6-C and Mobi-C cervical total disc replacement for cervical degenerative disc disease in adults.

BACKGROUND: Cervical total disc replacement (CTDR) is complicated by adjacent segment degeneration (ASD). Since non-physiological spine kinematics after CTDR was postulated to cause ASD, M6-C prosthesis has been developed to better replicate the natural kinematics of the intervertebral disc. This retrospective cohort study aims to compare the short-term outcomes between patients receiving either the M6-C or Mobi-C prostheses. METHODS: Patients who had refractory radiculopathy and/or myelopathy secondary to cervical degenerative disc disease and underwent CTDR between March 2004 and April 2017 were included. All CTDRs were performed by a single surgeon at a single institution. Self-reported clinical outcomes and radiological parameters were evaluated at baseline and final follow-up between March 2004 and April 2018. RESULTS: Sixty-two patients with greater than 1-year follow-up or who developed HO within 12 months of surgery, were included in the study. The mean radiological follow-up was 29.0 months (3-84 months), which includes 7 patients with less than 12 months follow-up who also developed HO. The changes in clinical and radiological measures were comparable between M6-C and Mobi-C prostheses. Thirty-seven out of 52 spinal segments (71.2%) and 10 out of 16 spinal segments (62.5%) developed HO in M6-C and Mobi-C group respectively. There was no significant difference in the rate of HO between the two groups. CONCLUSIONS: No short-term differences were found in clinical or radiological outcomes between patients who received either the M6-C or Mobi-C prosthesis. Further randomized trials with a long-term follow-up period are warranted to determine the safety and efficacy of M6-C prosthesis.

Relationship between sagittal balance and adjacent segment disease in surgical treatment of degenerative lumbar spine disease: meta-analysis and implications for choice of fusion technique.

STUDY DESIGN: Meta-analysis. OBJECTIVE: To conduct a meta-analysis investigating the relationship between spinopelvic alignment parameters and development of adjacent level disease (ALD) following lumbar fusion for degenerative disease. ALD is a degenerative pathology that develops at mobile segments above or below fused spinal segments. Patient outcomes are worse, and the likelihood of requiring revision surgery is higher in ALD compared to patients without ALD. Spinopelvic sagittal alignment has been found to have a significant effect on outcomes post-fusion; however, studies investigating the relationship between spinopelvic sagittal alignment parameters and ALD in degenerative lumbar disease are limited. METHODS: Six e-databases were searched. Predefined endpoints were extracted and meta-analyzed from the identified studies. RESULTS: There was a significantly larger pre-operative PT in the ALD cohort versus control (WMD 3.99, CI 1.97-6.00, p = 0.0001), a smaller pre-operative SS (WMD - 2.74; CI - 5.14 to 0.34, p = 0.03), and a smaller pre-operative LL (WMD - 4.76; CI - 7.66 to 1.86, p = 0.001). There was a significantly larger pre-operative PI-LL in the ALD cohort (WMD 8.74; CI 3.12-14.37, p = 0.002). There was a significantly larger postoperative PI in the ALD cohort (WMD 2.08; CI 0.26-3.90, p = 0.03) and a larger postoperative PT (WMD 5.23; CI 3.18-7.27, p < 0.00001). CONCLUSION: The sagittal parameters: PT, SS, PI-LL, and LL may predict development of ALD in patients' post-lumbar fusion for degenerative disease. Decision-making aimed at correcting these parameters may decrease risk of developing ALD in this cohort. These slides can be retrieved under Electronic Supplementary Material.

Resumption of Antithrombotic Agents in Chronic Subdural Hematoma: A Systematic Review and Meta-analysis.

BACKGROUND: The clinical decision whether and when to resume antithrombotics in patients with chronic subdural hematomas (CSDH) postoperatively is limited by a lack of quality evidence exploring this topic. Our study aims to assess the available evidence of patient complication outcomes, specifically hemorrhagic and thromboembolic events, following the resumption or non-resumption of antithrombotic agents postoperatively in CSDH patients already on these agents before CSDH. METHODS: We followed recommended PRISMA guidelines for systematic reviews. Electronic database searches were performed to identify included studies. Data were extracted and analyzed using meta-analysis. RESULTS: Eight studies were included for analysis. The most common indication for antithrombotic treatment before onset of CSDH was atrial fibrillation (29.6%), followed by prosthetic heart valve (16.6%), recent myocardial infarction (14.1%), prior stroke or transient ischemic attack (11.6%), and finally venous thromboembolism (8.3%). The overall hemorrhagic complication rate was 14.8% in the resumption group versus 18.6% in the no resumption group (P = 0.591). This did not differ between early (<2 weeks) versus late (>1 month) resumption (15% vs. 18.6%, P = 0.97). The rate of thromboembolism however was statistically lower in those who resumed antithrombotics (2.9% vs. 6.8%, P<0.001). There was a non-significant trend towards higher thromboembolic rates with early resumption (5.3% vs. 2.1%, P = 0.23). CONCLUSIONS: The decision to resume antithrombotics postoperatively in the clinical management of CSDH patients is a complex one and should therefore be a highly individualized process. Our meta-analysis demonstrates that in selected cases, it is feasible to resume early antithrombotic treatment without additional hemorrhagic or thromboembolic risk.

Lumbar Disk Arthroplasty for Degenerative Disk Disease: Literature Review.

Low back pain is the principal cause of long-term disability worldwide. We intend to address one of its main causes, degenerative disk disease, a spinal condition involving degradation of an intervertebral disk. Following unsuccessful conservative treatment, patients may be recommended for surgery. The two main surgical treatments for lumbar degenerative disk disease are lumbar fusion: traditional standard surgical treatment and lumbar disk arthroplasty, also known as lumbar total disk replacement. Lumbar fusion aims to relieve pain by fusing vertebrae together to eliminate movement at the joint, but it has been criticized for problems involving insignificant pain relief, a reduced range of motion, and an increased risk of adjacent segment degeneration. This leads to development of the lumbar total disk replacement technique, which aims to relieve pain replacing a degenerated intervertebral disk with a moveable prosthesis, thus mimicking the functional anatomy and biomechanics of a native intervertebral disk. Over the years a large range of prosthetic disks has been developed. The efficacy and current evidence for these prostheses are discussed in this review. The results of this study are intended to guide clinical practice and future lumbar total disk replacement device choice and design.

Anterior lumbar interbody fusion (ALIF) as an option for recurrent disc herniations: a systematic review and meta-analysis.

BACKGROUND: Recurrent intervertebral disc herniation is a relatively common occurrence after primary discectomy for lumbar intervertebral disc herniation. For recurrent herniations after repeat discectomies, a growing body of evidence suggests that fusion is effective in appropriately selected cases. Theoretically, anterior lumbar interbody fusion (ALIF) allows for comprehensive discectomy, less trauma to spinal nerves and paraspinal muscles and avoidance of the disadvantages of repeat posterior approaches. However, ALIF has also been associated with risk of vascular injury and retrograde ejaculation. This current systematic review and meta-analysis aims to assess the viability of ALIF as a surgical treatment for recurrent disc herniations. METHODS: Seven studies were identified from six electronic databases and secondary reference lists. Pre-defined endpoints were extracted from the included studies and meta-analyzed. RESULTS: For the 181 patients from included studies, ALIF resulted in significant average improvements in Oswestry Disability Index (ODI) scores (50.49%, P<0.001), Visual Analogue Scale (VAS) back pain scores (47.85%, P<0.001) and VAS leg pain scores (37.00%, P<0.001). Average blood loss was acceptable at 122 mL (P<0.001) and average operation duration was 89 minutes (P<0.001). Average hospital stay was 5.28 days (P<0.001). Only 22 perioperative complications were reported, with subsidence the most commonly reported complication. CONCLUSIONS: Pooled evidence suggests that ALIF is a feasible approach for the treatment of recurrent disc herniations, demonstrating significant improvements in back and leg pain and minimal complications. These findings warrant further investigation in large prospective registries and multi-center studies.

Focal hypermobility observed in cervical arthroplasty with Mobi-C.

In recent decades cervical arthroplasty, or cervical disc replacement, has been steadily increasing in popularity as a procedure for the treatment of degenerative pathologies of the cervical spine. This is based on an evolving body of literature that documents superior outcomes in cervical disc replacement over fusion, for both single and double level pathologies, in well selected patients. One of the more recent and popular implants currently on the market is the Mobi-C cervical artificial disc (LDR Medical; Troyes, France). In this paper we report on two cases where focal hypermobility was observed following total disc replacement using the Mobi-C cervical artificial disc. This is followed by a discussion as to potential contributing factors to this hypermobility in relation to both implant design, and operative technique, suggesting potential changes that might prevent this in future patients.