Study Design. Systematic review and meta-analysis. Objective. The aim of this study was to evaluate clinical outcomes, complications, and reoperations of minimally invasive posterior cervical foraminotomy (MI-PCF) for unilateral cervical radiculopathy without myelopathy, in comparison to anterior cervical decompression and fusion (ACDF). Summary of Background Data. ACDF is a standard treatment for cervical radiculopathy secondary to lateral disc herniation or foraminal stenosis. Recent studies have suggested MI-PCF to be an effective alternative to ACDF. However, concern for reoperation and whether similar improvements in clinical outcomes can be achieved has led to a debate in the literature. Methods. We comprehensively searched PubMed, CINAHL Plus, and SCOPUS utilizing terms related to MI-PCF. Two independent reviewers assessed potential studies and extracted data on clinical outcome scores (neck disability index [NDI], visual analog scale [VAS]-neck, and VAS-arm), reoperation proportion, and complications. Studies included were on noncentral cervical pathology, published in the last 10 years, had a sample size of >10 patients, and reported data on minimally invasive techniques for posterior cervical foraminotomy. Heterogeneity and publication bias analyses were performed. The pooled proportions of each outcome were compared to those of ACDF obtained from two previously published studies. Results. Fourteen studies were included with data of 1216 patients. The study population was 61.8% male, with a mean age of 51.57 years, and a mean follow-up of 30 months. MI-PCF resulted in a significantly greater improvement in VAS-arm scores compared to ACDF, and similar improvements in VAS-neck and NDI scores. Proportions of complications and reoperations were similar between the two cohorts. The most common complications were transient neuropraxia, wound-related, and durotomy. Conclusion. Our findings suggest that MI-PCF may be utilized as a safe and effective alternative to ACDF in patients with unilateral cervical radiculopathy without myelopathy, without concern for increased reoperations or complications. Level of Evidence: 3

OBJECTIVEThe objective of this study was to compare anterior cervical discectomy and fusion (ACDF) and minimally invasive posterior cervical foraminotomy (MI-PCF) with tubes for the treatment of cervical radiculopathy in terms of the 1) overall revision proportion, 2) index and adjacent level revision rates, and 3) functional outcome scores.METHODSThe authors retrospectively reviewed the records of consecutive patients who had undergone ACDF or MI-PCF at a single institution between 2009 and 2014. Patients treated for cervical radiculopathy without myelopathy and with a minimum 2-year follow-up were compared according to the procedure performed for their pathology. Primary outcome measures included the overall rate of revision with fusion and overall revision proportion as well as the rate of index and adjacent level revisions per year. Secondarily, self-reported outcome measures—Neck Disability Index (NDI) and visual analog scale (VAS) for arm (VASa) and neck (VASn) pain—at the preoperative and postoperative evaluations were analyzed. Standard binomial and categorical comparative analyses were performed.RESULTSForty-nine consecutive patients were treated with MI-PCF, and 210 consecutive patients were treated with ACDF. The mean follow-up for the MI-PCF cohort was 42.9 ± 6.6 months (mean ± SD) and for the ACDF cohort was 44.9 ± 10.3 months. There was no difference in the overall revision proportion between the two cohorts (4 [8.2%] of 49 MI-PCF vs. 12 [5.7%] of 210 ACDF, p = 0.5137). There was no difference in the revision rate per level per year (3.1 vs. 1.7, respectively, p = 0.464). Moreover, there was no difference in the revision rate per level per year at the index level (1.8 vs. 0.7, respectively, p = 0.4657) or at an adjacent level (1.3 vs. 1.1, p = 0.9056). Neither was there a difference between the cohorts as regards the change from preoperative to final postoperative functional outcome scores (NDI, VASa, VASn).CONCLUSIONSMinimally invasive PCF for the treatment of cervical radiculopathy demonstrates rates of revision at the index and adjacent levels similar to those following ACDF. In order to confirm the positive efficacy and cost analysis findings in this study, future studies need to extend the follow-up and show that the rate of revision with fusion does not increase substantially over time.

Study DesignRetrospective cohort study (level of evidence: 4).PurposeTo describe the potential comorbid, operative, and radiographic risk factors for the development of clinically-relevant pseudarthrosis following minimally-invasive transforaminal lumbar interbody fusion (MIS-TLIF).Overview of LiteratureMIS-TLIF has shown long-term clinical outcomes with decreased perioperative morbidity and earlier return to work, similar to those of open TLIF. However, unsuccessful fusion still remains a concern. The impacts of various patient, operative, and radiographic risk factors have not been evaluated for their potential association with pseudarthrosis related to MIS-TLIF.MethodsBetween 2012 and 2015, 204 consecutive patients underwent one or two-level MIS-TLIF at St. Joseph's University Medical Center, Paterson, NJ, USA; they had a minimum of 1 year of follow-up. The patients were divided into two cohorts: those who developed clinically-relevant pseudarthrosis and those who did not. Clinically-relevant pseudarthrosis was determined by both evidence on computed tomography and presence of continued clinical symptoms at 1-year follow-up.ResultsRevision surgery was the only identified non-radiographic factor associated with pseudarthrosis. Disc angle had the highest (R2=0.8), followed by anterior disc height (R2=0.79). Although posterior disc height and the ratio of anterior to posterior disc height showed a marked relationship with the outcome, the R2-values were <0.3, thus indicating a less-strong correlation. The overall pseudarthrosis rate was 8%. No statistically significant differences were identified between the two cohorts with respect to mean age, sex, medical comorbidities, smoking status, or number of levels fused.ConclusionsClinically-relevant pseudarthrosis is not uncommon following MIS-TLIF. In the current study, undergoing revision surgery, disc angle, and anterior disc height were observed to be associated with clinically-relevant pseudarthrosis. This study demonstrated that the patient population may benefit from an alternate approach.