Surgical Treatment of Recurrent Lumbar Disk Herniation: A Systematic Review and Meta-analysis.

Consensus is lacking regarding optimal surgical treatment of recurrent lumbar disk herniation. A systematic search of multiple databases was conducted for studies evaluating outcomes after treatment for recurrent lumbar disk herniation. Treatment options included decompression surgeries and fusion surgeries. Although fusion surgeries eliminated re-recurrence of disk herniation, this coincided with higher incidences of complications and reoperation. Decompression surgeries and fusion surgeries both resulted in improvements in Japanese Orthopaedic Association, Oswestry Disability Index, and visual analog scale back and leg scores postoperatively (P<.05). The complication risk profiles of decompression surgeries and fusion surgeries must be balanced with the risk of disk herniation re-recurrence, as both procedures lead to improvements in functional outcomes. [Orthopedics. 2018; 41(4):e457-e469.].

The Effect of Ketorolac on Thoracolumbar Posterolateral Fusion: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: The purpose of this study was to evaluate the effect of postoperative ketorolac administration (ie, dosage and duration of use) on pseudarthrosis following thoracolumbar posterolateral spinal fusions. SUMMARY OF BACKGROUND DATA: Ketorolac is a nonsteroidal anti-inflammatory drug often administered for pain control after spine surgery. The main concern with ketorolac is the risk of pseudarthrosis following fusion. MATERIALS AND METHODS: A systematic search of multiple medical reference databases was conducted for studies detailing postoperative ketorolac use in lumbar fusion and scoliosis surgery in adult and pediatric patients, respectively. Meta-analysis was performed using the random-effects model for heterogeneity as this study analyzes heterogenous patient populations undergoing variable approaches to fusion and variable numbers of levels with variable means of detection of pseudarthrosis. Outcome measure was pseudarthrosis. RESULTS: Overall, 6 studies totaling 1558 patients were reviewed. Pseudarthrosis was observed in 119 (7.6%) patients. Pseudarthrosis were observed in adults with ketorolac administered for >2 days [odds ratio (OR), 3.44, 95% confidence interval (95% CI), 1.87-6.36; P<0.001], adults with doses of ≥120 mg/d (OR, 2.93, 95% CI, 1.06-8.12; P=0.039), and adults with ketorolac administered for >2 days and at doses ≥120 mg/d (OR, 4.75, 95% CI, 2.34-9.62; P<0.001). Ketorolac use in smokers was associated with pseudarthrosis (OR, 8.71, 95% CI, 2.23-34.0; P=0.002). CONCLUSION: Ketorolac, when administered for >2 days and/or at a dose of ≥120 mg/d, is associated with pseudarthrosis in adults after posterolateral lumbar fusion. Ketorolac use in smokers is also associated with pseudarthrosis.

Effectiveness of Reoperations for Adjacent Segment Disease Following Lumbar Spinal Fusion.

Although several options are available to address adjacent segment disease (ASD), the most effective surgical treatment has not been determined. In addition, it is important to subdivide ASD into stenosis with or without instability to determine if a decompression alone vs an extension of fusion is necessary. A systematic search of multiple medical reference databases was conducted for studies on surgical treatment of ASD. The primary outcome measures used were radiographic and clinical success rates. Meta-analysis was completed to determine effect summary values, 95% confidence intervals, and Q statistic and I2 values, using the random effects model for heterogeneity. The search yielded 662 studies, of which 657 were excluded. A total of 5 (level IV) studies with a total of 118 patients were included in this review. In 2 studies (46 patients), stenosis without instability was the indication for reoperation for ASD. However, extension of fusion was the modality of choice for the treatment of ASD in all studies. Overall clinical improvement (in back and/or leg pain scores) was noted in 71.3% of patients (95% confidence interval, 37.4-100), while radiographic fusion was noted in 89.3% of patients (95% confidence interval, 51.2-100). Following reoperation for ASD, revision surgery rates ranged from 4.5% to 23.1% at last clinical follow-up. There is variability in the clinical improvement following lumbar fusion for ASD. In addition, little literature exists regarding the optimal treatment options for patients with ASD for stenosis with or without instability. [Orthopedics. 2018; 41(2):e161-e167.].

Intraoperative Neuromonitoring for Anterior Cervical Spine Surgery: What Is the Evidence?

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: The goal of this study was to (i) assess the risk of neurological injury after anterior cervical spine surgery (ACSS) with and without intraoperative neuromonitoring (ION) and (ii) evaluate differences in the sensitivity and specificity of ION for ACSS. SUMMARY OF BACKGROUND DATA: Although ION is used to detect impending neurological injuries in deformity surgery, it's utility in ACSS remains controversial. METHODS: A systematic search of multiple medical reference databases was conducted for studies on ION use for ACSS. Studies that included posterior cervical surgery were excluded. Meta-analysis was performed using the random-effects model for heterogeneity. Outcome measure was postoperative neurological injury. RESULTS: The search yielded 10 studies totaling 26,357 patients. The weighted risk of neurological injury after ACSS was 0.64% (0.23-1.25). The weighted risk of neurological injury was 0.20% (0.05-0.47) for ACDFs compared with 1.02% (0.10-2.88) for corpectomies. For ACDFs, there was no difference in the risk of neurological injury with or without ION (odds ratio, 0.726; confidence interval, CI, 0.287-1.833; P = 0.498). The pooled sensitivities and specificities of ION for ACSS are 71% (CI: 48%-87%) and 98% (CI: 92%-100%), respectively. Unimodal ION has a higher specificity than multimodal ION [unimodal: 99% (CI: 97%-100%), multimodal: 92% (CI: 81%-96%), P = 0.0218]. There was no statistically significant difference in sensitivities between unimodal and multimodal [68% vs. 88%, respectively, P = 0.949]. CONCLUSION: The risk of neurological injury after ACSS is low although procedures involving a corpectomy may carry a higher risk. For ACDFs, there is no difference in the risk of neurological injury with or without ION use. Unimodal ION has a higher specificity than multimodal ION and may minimize "subclinical" intraoperative alerts in ACSS. LEVEL OF EVIDENCE: 3.

Comparative analysis of techniques to prevent laparoscopic fogging.

PURPOSE: To evaluate the efficiency and efficacy of two common and commercially available methods to resolve lens fogging: a Fluid Warming System (O.R. Solutions, Chantilly, VA) and the Clearify Visualization System (Covidien, Mansfield, MA). MATERIAL AND METHODS: We prospectively evaluated 40 patients undergoing laparoscopic renal procedures with the Fluid Warming System (first 20 cases) and then the Clearify Visualization System (second 20 cases). We utilized the standard Fluid Warming System per a 30-second modified protocol established in our laboratory. We used the Clearify according to manufacturer instructions. For each procedure we documented the etiology of each episode of visual obstruction, procedure type and surgery duration. We performed a cost analysis. For all cases we used the same insufflator, insufflation trocar location and trocar configuration. RESULTS: All 40 patients completed the study protocol without incident. The mean fogging events per hour for the Fluid Warming System and Clearify Visualization System were 0.7 (0-2.52) and 1.4 (0-5.02), respectively (P = 0.045). Surgery duration and cost per procedure were similar for both systems. CONCLUSION: The Fluid Warming System with modified technique was found to have less fogging events than the Clearify Visualization System, with no difference in operative time or cost.

Development and evaluation of a retroperitoneal dialysis porcine model.

OBJECTIVES: We attempted to create a surgical model to evaluate the retroperitoneal space for the ability to transfer solutes through the retroperitoneal membrane. Our dual objectives were to develop a technique to assess the feasibility of retroperitoneal dialysis (RPD) in a porcine model. METHODS: We incorporated two 35-kg Yorkshire pigs for this pilot study. In the first animal, we clamped renal vessels laparoscopically. In the second animal, we embolized renal arteries. In both animals, we dilated the retroperitoneal space bilaterally and deployed dialysis catheters. We measured serum creatinine (Cr), urea, and electrolytes at baseline 6 hours before the dialysis and every 4 hours after. RESULTS: We successfully created retroperitoneal spaces bilaterally and deployed dialysis catheters in both animals. In the first animal, dialysate and plasma Cr ratio (D/P) on the left and right side were 0.43 and 0.3, respectively. Cr clearance by 40 minutes of dialysis treatment was 6.3 mL/min. The ratio of dialysate glucose at 4 hours dwell time to dialysate glucose at 0 dwell time (D/D0) for left/rights sides were 0.02 and 0.02, respectively. kt/Vurea was 0.43. In the second animal, D/P Cr for left/right sides were 0.34 and 0.33, respectively. kt/Vurea was 0.17. We euthanized the pigs due to fluid collection in the peritoneal space and rapid increase of serum Cr, urea, and electrolytes. CONCLUSIONS: We demonstrated the feasibility of creation of a functionally anephric porcine model with successful development of retroperitoneal spaces using balloon inflation. Notwithstanding minimal clearance and limited diffusion capacity in this experiment, additional studies are needed to examine potential use of retroperitoneal space for peritoneal dialysis.

Paraspinal Muscle Atrophy After Lumbar Spine Surgery.

Paraspinal muscles are commonly affected during spine surgery. The purpose of this study was to assess the potential factors that contribute to paraspinal muscle atrophy (PMA) after lumbar spine surgery. A comprehensive review of the available English literature, including relevant abstracts and references of articles selected for review, was conducted to identify studies that reported PMA after spinal surgery. The amount of postoperative PMA was evaluated in (1) lumbar fusion vs nonfusion procedures; (2) posterior lumbar fusion vs anterior lumbar fusion; and (3) minimally invasive (MIS) posterior lumbar decompression and/or fusion vs non-MIS equivalent procedures. In total, 12 studies that included 529 patients (262 men and 267 women) were reviewed. Of these, 365 patients had lumbar fusions and 164 had lumbar decompressions. There was a significantly higher mean postoperative volumetric PMA with fusion vs nonfusion procedures (P=.0001), with posterior fusion vs anterior fusion (P=.0001), and with conventional fusions vs MIS fusions (P=.001). There was no significant difference in mean volumetric lumbar PMA with MIS decompression vs non-MIS decompression (P=.56). There was significantly higher postoperative PMA with lumbar spine fusions, posterior procedures, and non-MIS fusions.