Article Figures & Data
Figures
- Figure 1
The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flowchart of selected endoscopy and interspinous process spacer studies. ODI, Oswestry Disability Index; VAS, visual analog scale.
- Figure 2
Forest plot of calculated Oswestry Disability Index (ODI) effect sizes (ES), 95% CI, and the number of patients enrolled in each of the endoscopic spinal surgery and interspinous process spacer (IPS) studies listed in alphabetical order according to the first author’s name. The number of individual study patients is represented by the size of the square. The calculated pooled standardized ES for changes in ODI for the endoscopy studies was 0.917 (95% CI = 0.891–0.943). The corresponding ES for the IPS procedures was 0.798 (95% CI = 0.713–0.883). The analysis of variance Q test of difference showed a statistically higher ODI ES with endoscopy than with the IPS procedure (P = 0.001). Prometa 3 plotted the ES data in terms of non-standardized differences.
- Figure 3
Forest plot of calculated visual analog scale (VAS)-back effect sizes (ES), 95% CI, and the number of patients enrolled in each of the endoscopic spinal surgery and interspinous process spacer (IPS) studies listed in alphabetical order according to the first author’s name. The number of individual study patients is represented by the size of the square. The calculated pooled standardized ES for changes in VAS-back for the endoscopy studies was 0.661 (95% CI = 0.585–0.738). The corresponding ES for the IPS procedures was 0.784 (95% CI = 0.644–0.923). The analysis of variance Q test of difference indicated that this difference in VAS-back ES was not statistically significant (P = 0.187). Prometa 3 plotted the ES data in terms of non-standardized differences.
- Figure 4
Forest plot of calculated visual analog scale (VAS)-leg effect sizes (ES), 95% CI, and the number of patients enrolled in each of the endoscopic spinal surgery and interspinous process spacer (IPS) studies listed in alphabetical order according to the first author’s name. The number of individual study patients is represented by the size of the square. The calculated pooled standardized ES for changes in VAS-leg for the endoscopy studies was 0.885 (95% CI = 0.852–0.917). The corresponding ES for the IPS procedures was 0.851 (95% CI = 0.767–0.935). The analysis of variance Q test of difference indicated that this difference in VAS-leg ES was not statistically significant (P = 0.427).
- Figure 5
Meta-analysis regression plot of effect size vs age in years using random effects model showed no significant correlation (P = 0.289).
- Figure 6
Meta-analysis plot of effect size (ES) vs follow-up in months using random effects model showed a statistically significantly higher proportion of studies (all of the interspinous spacer studies) with either 24 months follow-up or more with higher ES numbers in the longer follow-up studies (P = 0.026).
- Figure 7
Funnel plot assessing publication bias (SE vs effect size).
Tables
- Table 1
List of endoscopy studies included into the meta-analysis with brief summary of study highlights.
No. Authors Year Title Reference Study Highlights 1. Ahn Y, Keum HJ, et al5 2019 Transforaminal endoscopic decompression for lumbar lateral recess stenosis: an advanced surgical technique and clinical outcomes World Neurosurg. 2019;125:e916–e924. Retrospective 2-y follow-up study on 45 patients treated with transforaminal endoscopic decompression for lumbar lateral recess stenosis. 2. Ahn Y, Lee SG, et al102 2019 Transforaminal endoscopic lumbar discectomy vs open lumbar microdiscectomy: a comparative cohort study with a 5-year follow-up Pain Physician. 2019;22:295–304. Long-term prospective outcome analysis of PELD vs microdiscectomy on 335 with 5-y follow-up. 3. Bai YB, Xu L, et al103 2012 Diagnosis and treatment of lumbar disc herniation by discography and percutaneous transforaminal endoscopic surgery Zhonghua Yi Xue Za Zhi. 2012;92:3350–3353. Retrospective analysis (26 mo) of 119 LDH patients by discography and transforaminal PELD surgery. 4. Choi G, Lee SH, et al104 2007 Percutaneous endoscopic discectomy for extraforaminal lumbar disc herniations: extraforaminal targeted fragmentectomy technique using working channel endoscope Spine (Phila Pa 1976). 2007;32:E93–E99. A retrospective analysis (34.1 mo follow-up) of 41 patients with soft lumbar extraforaminal disc herniations treated by endoscopic extraforaminal approach under local anesthesia. 5. Choi G, Modi HN, et al105 2013 Clinical results of XMR-assisted percutaneous transforaminal endoscopic lumbar discectomy J Orthop Surg Res. 2013;8:14. Prospective study on 89 patients (2-y follow-up) undergoing PELD for LDH in an operative suite equipment with fluoroscopic and magnetic resonance imaging. 6. Choi KC, Kim JS, et al106 2016 Percutaneous endoscopic lumbar discectomy as an alternative to open lumbar microdiscectomy for large lumbar disc herniation Pain Physician. 2016;19:E291–E300. Retrospective observational study (2-y follow-up) on 20 endoscopic and 23 open lumbar discectomy patients. 7. Choi KC and Park CK107 2016 Percutaneous endoscopic lumbar discectomy for L5-S1 disc herniation: consideration of the relation between the iliac crest and L5-S1 disc Pain Physician. 2016;19:E301–E308. Retrospective study on 51 patients (2-y follow-up) treated either with transforaminal PELD or interlaminar PELD. 8. Chung J, Kong C, et al7 2019 Percutaneous endoscopic lumbar foraminoplasty for lumbar foraminal stenosis of elderly patients with unilateral radiculopathy: radiographic changes in magnetic resonance images J Neurol Surg A Cent Eur Neurosurg. 2019;80:302–311. Retrospective study (2-y follow-up) of 24 patients over 65 y of age who underwent percutaneous endoscopic lumbar foraminoplasty to treat unilateral radiculopathy caused by lumbar foraminal stenosis. 9. Dey PC and Nanda SN108 2019 Functional outcome after endoscopic lumbar discectomy by Destandau’s technique: a prospective study of 614 patients Asian Spine J. 2019;13:786–792. Retrospective study on 614 patients who underwent endoscopic lumbar discectomy using Destandau endospine system after a minimum follow-up of 12 mo and maximum up to 54 mo. 10. Eun SS, Lee SH, et al109 2018 Transforaminal percutaneous endoscopic lumbar diskectomy for downmigrated disk herniations: lever-up, rotate, and tilt technique J Neurol Surg A Cent Eur Neurosurg. 2018;79:163–168. Retrospective study (2-y follow-up) of 18 patients who underwent transforaminal PELD. 11. Gibson JNA, et al110 2017 A randomized controlled trial of transforaminal endoscopic discectomy vs microdiscectomy Eur Spine J. 2017;26:847–856. Prospective trial on 143 patients, age 25–70 y with single-level lumbar prolapse and radiculopathy with 70 randomized transforaminal PELD under conscious sedation and another 70 patients to microdiscectomy under general anesthesia. 12. Kim HS, Adsul N, et al111 2018 A mobile outside-in technique of transforaminal lumbar endoscopy for lumbar disc herniations J Vis Exp. 2018;(138):57999. Prospective study on mobile outside-in treatment of LDH in 184 consecutive patients with unilateral lower limb radiculopathy—19 ± 6 mo follow-up. 13. Kim JE and Choi DJ112 2018 Biportal arthroscopic spinal surgery (BASS) with 30 degrees arthroscopy for far lateral approach of L5-S1 - technical note J Orthop. 2018;15:354–358. Retrospective study on 12 patients with far lateral approach of biportal arthroscopic technique using 30 degrees arthroscopy for foraminal decompression of L5-S1. 14. Komp M, Hahn P, et al113 2014 Operation of lumbar zygoapophyseal joint cysts using a full-endoscopic interlaminar and transforaminal approach: prospective 2-year results of 74 patients Surg Innov. 2014;21:605–614. Prospective study (2-y follow-up) of 74 full-endoscopic interlaminar and transforaminal PELD patients treat for lumbar z-joint cysts. 15. Lee SH and Kang HS30 2010 Percutaneous endoscopic laser annuloplasty for discogenic low back pain World Neurosurg. 2010;73:198–206. Retrospective study on 37 patients treated at a single-level laser-assisted spinal endoscopy vs percutaneous endoscopic laser annuloplasty with a mean follow-up of 9.7 mo. 16. Lewandrowski KU, de Carvalho PST, et al127 2020 Outcomes with transforaminal endoscopic vs percutaneous laser decompression for contained lumbar herniated disc: a survival analysis of treatment benefit J Spine Surg. 2020;6:S84–S99. Retrospective study of 248 patients consisting of 162 patients in the endoscopic group and 86 patients in the laser discectomy group with average 43.5 mo follow-up. 17. Li H, Jiang C, et al114 2018 Comparison of MED and PELD in the treatment of adolescent lumbar disc herniation: A 5-year retrospective follow-up World Neurosurg. 2018;112:e255–e260. Retrospective study (48 mo follow-up) comparing the efficacy and safety of MED (30 patients) and PELD (48 patients) in the treatment of ALDH. 18. Liu C, Chu L, et al115 2017 Percutaneous endoscopic lumbar discectomy for highly migrated lumbar disc herniation Pain Physician. 2017;20:E75–E84. Retrospective study (3 mo follow-up) on 73 patients with highly migrated LDH treated with PELD comparing 3 approaches. 19. Pan F, Shen B, et al116 2016 Transforaminal endoscopic system technique for discogenic low back pain: a prospective cohort study Int J Surg 2016;35:134–138. Retrospective consecutive case series with 62 patients with 1-level discogenic low back pain with 26.8 ± 4.2 mo follow-up. 20. Soliman HM117 2013 Irrigation endoscopic discectomy: a novel percutaneous approach for lumbar disc prolapse Eur Spine J. 2013;22:1037–1044. Prospective case series of 43 patients with uncontained LDH underwent irrigation endoscopic discectomy surgery with 24 mo follow-up. 21. Song H, Hu W, et al118 2017 Percutaneous endoscopic interlaminar discectomy of L5-S1 disc herniation: a comparison between intermittent endoscopy technique and full endoscopy technique J Orthop Surg Res. 2017;12:162. Retrospective study comparing full endoscopy technique (65 patients) or intermittent endoscopy technique (61 patients) with average 27 mo follow-up. 22. Teli M, Lovi A, et al119 2017 Higher risk of dural tears and recurrent herniation with lumbar microendoscopic discectomy Eur Spine J. 2010;19:443–450. Randomized controlled trial of 240 patients was randomized to microendoscopic (group 1), micro (group 2), or open (group 3) discectomy with minimum 2-y follow-up. 23. Tu Z, Li YW, et al120 2010 Clinical outcome of full-endoscopic interlaminar discectomy for single-level lumbar disc herniation: a minimum of 5-year follow-up Pain Physician. 2017;20:E425–E430. Retrospective study of 152 patients with single-level LDH located at either L4-L5 or L5-S1 who underwent either FEID (72 patients) or MED (80 patients) with >5-y follow-up. 24. Tu Z, Wang B, et al121 2018 Early experience of full-endoscopic interlaminar discectomy for adolescent lumbar disc herniation with sciatic scoliosis Pain Physician. 2018;21:E63–E70. Retrospective case series of patients under age 20 with single-level ALDH with and without scoliosis treated with FEID. Average follow-up 39 mo. 25. Wang Y, Zhang W, et al122 2018 Transforaminal endoscopic discectomy for treatment of central disc herniation: surgical techniques and clinical outcome Pain Physician. 2018;21:E113–E123. Retrospective 2-y follow-up study of 69 consecutive patients treated with transforaminal PELD central disc herniation. 26. Wang YP, Zhang W, et al123 2016 Evaluation of transforaminal endoscopic discectomy in treatment of obese patients with lumbar disc herniation Med Sci Monit. 2016;22:2513–2519. Prospective study of 69 obese patients with LDH (35 men and 34 women; age range, 24–43 y) treated for LDH with PELD. 27. Xu B, Xu H, et al124 2018 Bilateral decompression and intervertebral fusion via unilateral fenestration for complex lumbar spinal stenosis with a mobile microendoscopic technique Medicine (Baltimore). 2018;97:e9715. Retrospective 3-y follow-up study on 61 patients with complex lumbar spinal stenosis (lumbar canal stenosis combined with degenerative spondylolisthesis, instability, and scoliosis) treated with Destandau-type mobile microendoscopic discectomy. 28. Youn MS, Shin JK, et al125 2018 Endoscopic posterior decompression under local anesthesia for degenerative lumbar spinal stenosis J Neurosurg Spine. 2018;29:661–666. Retrospective study of 50 patients (28 women and 22 men) treated for LDH with endoscopic posterior decompression under local anesthesia followed up to 24 mo postoperatively. 29. Zhang B, Kong Q, et al126 2019 Short-term effectiveness of percutaneous endoscopic transforaminal bilateral decompression for severe central lumbar spinal stenosis Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2019;33:1399–1405. Retrospective study on effectiveness and safety of bilateral transforaminal bilateral PELD decompression for severe central lumbar spinal stenosis in 44 patients with average follow-up of 24.8 mo. ALDH, adolescent lumbar disc herniation; FEID, full-endoscopic interlaminar discectomy; LDH, lumbar disc herniation; MED, minimally endoscopic discectomy; PELD, percutaneous endoscopic lumbar discectomy.
- Table 2
List of interspinous process spacer studies included into the meta-analysis with brief summary of study highlights.
# Authors Year Title Reference Study Highlights 1. Abdel Ghany W, Amer A, et al128 2016 Evaluation of interspinous spacer outcomes in degenerative lumbar canal stenosis: clinical study World Neurosurg. 2016;95:556–564 e553. Prospective 12 mo study comparing 28 decompression. In the second group, 25 patients underwent decompressive laminectomy. 2. Errico TJ, Kamerlink JR, et al70 2009 Survivorship of coflex interlaminar-interspinous implant SAS J. 2009;3:59–67. Retrospective study of 127 patients underwent placement of a coflex implant for various stenosis-related indications with a mean follow-up of 6.3 y. 3. Gu H, Chang Y, et al131 2018 Wallis interspinous spacer for treatment of primary lumbar disc herniation: three-year results of a randomized controlled trial World Neurosurg. 2018;120:e1331–e1336. Prospective, single-center, randomized, controlled clinical trial comparing the postoperative results of lumbar discectomy with and without the Wallis implant. A total of 77 patients were included in the randomized study group, with 40 undergoing lumbar discectomy with Wallis implant insertion (Wallis group) and 37 undergoing lumbar discectomy alone (control group). 4. Haley TR, Miller LE, et al129 2013 Midterm outcomes of a prospective randomized controlled trial of interspinous spacer treatment for moderate lumbar spinal stenosis PM&R. 2013:S289. Prospective, randomized, controlled, IDE trial. Setting: 23 hospitals in the United States. Participants: 145 patients with intermittent neurogenic claudication secondary to moderate LSS and unresponsive to conservative care. Interventions: Patients were randomly treated with ISP implant (Superion 75; X-Stop 70) and followed for 18 mo. 5. Korovessis P, Syrimpeis V, et al130 2018 PEEK vs silicon interspinous spacer for reduction of supradjacent segment degeneration following decompression and short-segment instrumentation for degenerative lumbar spinal stenosis Adv Orthop. 2018;2018:1623647. A consecutive retrospective study of 55 patients on incidence of ASD and spinopelvic balance in short lumbosacral instrumentation for degenerative LSS with IPS placement in the supradjacent segment and its interaction with spinopelvic balance: 17 patients received polyetheretherketone (PEEK) IPS; 18 received Silicon IPS and were compared with 20 controls without any ISP. 6. Lønne G, Johnsen LG, et al132 2015 Comparing cost-effectiveness of X-Stop with minimally invasive decompression in lumbar spinal stenosis: a randomized controlled trial Spine (Phila Pa 1976). 2015;40:514–520. Randomized clinical trial of 96 patients with 1-level or 2-level LSS, and 2-y follow-up to compare the cost-effectiveness of X-Stop to minimally invasive decompression in patients with symptomatic LSS. 7. Masala S, Fiori R, et al133 2012 Percutaneous decompression of lumbar spinal stenosis with a new interspinous device Cardiovasc Intervent Radiol. 2012;35:368–374. Retrospective 6-mo follow-up study with the Falena ISP implanted at a single level in 26 patients (17 men; mean age, 69 (range, 54–82 y)) suffering degenerative LSS. 8. Masala S, Marcia S, et al42 2016 Degenerative lumbar spinal stenosis treatment with Aperius PerCLID system and Falena(R) interspinous spacers: 1-year follow-up of clinical outcome and quality of life. Interv Neuroradiol. 2016;22:217–226. Retrospectively 12-mo follow-up study of 24 patients (20 men and 4 women; 61 ± 9 y old), treated with an implantation of the Aperius, PerCLID system, and from 35 patients (29 men and 6 women; 65 ± 9 y old) treated with the Falena interspinous device. 9. Miller LE and Block JE46 2012 Interspinous spacer implant in patients with lumbar spinal stenosis: preliminary results of a multicenter, randomized, controlled trial Pain Res Treat. 2012;2012:823509. A prospective, randomized, controlled trial 6-mo follow-up IDE trial of ISP (Superion) vs those treated with an FDA-approved spacer (X-Stop). A total of 166 patients with moderate LSS unresponsive to conservative care were treated randomly with the Superion (n = 80) or X-Stop (n = 86) ISP. 10. Nunley PD, Patel VV, et al134 2017 Superion interspinous spacer treatment of moderate spinal stenosis: 4-year results World Neurosurg. 2017;104:279–283. Prospective 4-y clinical outcomes study in patients with intermittent neurogenic due to moderate LSS treated with minimally invasive standalone ISP decompression using the Superion device. The data were extracted from a randomized, controlled FDA IDE trial. 11. Patel VV, Whang PG, et al53 2014 Two-year clinical outcomes of a multicenter randomized controlled trial comparing two interspinous spacers for treatment of moderate lumbar spinal stenosis BMC Musculoskelet Disord. 2014;15:221. Prospective, multicenter, randomized, 2-y controlled trial in patients with moderate LSS treated with the Superion (experimental) or the X-Stop, an FDA-approved ISP (control). A total of 250 patients with moderate LSS unresponsive to conservative care were randomly allocated to treatment with the experimental (n = 123) or control (n = 127) ISP. 12. Postacchini R, Ferrari E, et al135 2011 Aperius interspinous implant vs open surgical decompression in lumbar spinal stenosis Spine J. 2011;11:933–939. Prospective comparative cohort 12 mo study of patients with moderate or severe LSS treated with the Aperius or by open decompression. 13. Puzzilli F, Gazzeri R, et al141 2014 Interspinous spacer decompression (X-Stop) for lumbar spinal stenosis and degenerative disk disease: a multicenter study with a minimum 3-year follow-up Clin Neurol Neurosurg. 2014;124:166–174. Prospective 36 mo study comparing clinical outcomes of 422 ISP patients (X-Stop) to 120 control cases were managed conservatively. 14. Richter A, Schutz C, et al136 2010 Does an interspinous device (Coflex) improve the outcome of decompressive surgery in lumbar spinal stenosis? One-year follow up of a prospective case control study of 60 patients Eur Spine J. 2010;19:283–289. Prospective 12 mo study of 60 patients comparing 1-level or 2-level symptomatic LSS decompressive surgery to LSS decompressive surgery (30 patients) and additional implantation of the Coflex ISP (30 patients). 15. Senegas J137 2002 Mechanical supplementation by non-rigid fixation in degenerative intervertebral lumbar segments: the Wallis system Eur Spine J. 2002;11(suppl 2):S164–S169. A 3-y prospective cohort study comparing discectomy alone with discectomy and ISP implantation using Wallis. 16. Sobottke R, Schluter-Brust K, et al142 2009 Interspinous implants (X-Stop, Wallis, Diam) for the treatment of LSS: is there a correlation between radiological parameters and clinical outcome? Eur Spine J. 2009;18:1494–1503. Retrospective comparative study of 129 consecutive patients with LSS treated with X-Stop, Wallis, or Diam. 17. Surace MF, Fagetti A, et al138 2012 Lumbar spinal stenosis treatment with Aperius perclid interspinous system Eur Spine J. 2012;21(suppl 1): S69-S74. Prospective cohort 18 mo study of 37 patients (20 men and 17 women) with mean age of 64.3 y treated with Aperius and PercLID ISP) foraminal stenosis. 18. Stromqvist BH, Berg S, et al139 2013 X-Stop vs decompressive surgery for lumbar neurogenic intermittent claudication: randomized controlled trial with 2-year follow-up. Spine (Phila Pa 1976). 2013;38:1436–1442. Prospective comparative 18 mo cohort study of 100 patients with symptomatic 1-level or 2-level LSS: 50 in the X-Stop group and 50 in the decompression group. 19. Tekmyster G, Sayed D, et al140 2019 Interspinous process decompression with the Superion® spacer for lumbar spinal stenosis: real-world experience from a device registry Med Devices (Auckl). 2019;12:423–427. Retrospective study of clinical outcomes with Superion. Indirect decompression system in 1426 LSS patients with intermittent neurogenic claudication treated by 316 physicians at 86 clinical sites in the United States participated. ASD, adjacent segment degeneration; FDA, Food and Drug Administration; IDE , investigational device exemption; ISP, interspinous spacer; LSS, lumbar spinal stenosis.
- Table 3
Analysis of effect size, heterogeneity, and ANOVA testing of difference by surgery type.
Outcome Measure Type of Surgery Number of Studies Included in This Analysis (Multiple Study Groups Possible) Effect Sizes Lower Limit Upper Limit Higgins I 2 Statistic of Heterogeneity Variance SE N Oswestry Disability Index Endoscopy 29 0.912 0.891 0.943 0% 0.0002 0.0132 4364 Interspinous process spacer 22 0.798 0.713 0.883 0% 0.0019 0.0435 2098 ANOVA Q random effects test with separate estimates of T 2 P = 0.001 Total N patients 6462 VAS-back Endoscopy 14 0.661 0.585 0.734 0% 0.0015 0.0389 1574 Interspinous process spacer 15 0.784 0.644 0.923 0% 0.0050 0.0711 2098 ANOVA Q random effects test with separate estimates of T 2 P = 0.187 Total N patients 3672 VAS-leg Endoscopy 28 0.885 0.852 0.917 0% 0.000 0.017 4292 Interspinous process spacer 24 0.851 0.767 0.935 0% 0.002 0.043 3598 ANOVA Q random effects test with separate estimates of T 2 P = 0.427 Total N patients 7890 ANOVA, analysis of variance; VAS, visual analog scale.
- Table 5
Analysis of effect size, heterogeneity, and ANOVA testing of difference by study type.
Outcome Measure Study Design Number of Studies Included in This Analysis (Multiple Study Groups Possible) Effect Size Lower Limit Upper Limit Higgins I 2 Statistic of Heterogeneity Variance SE N Oswestry Disability Index Prospective study 8 0.890 0.821 0.960 0% 0.0013 0.0354 1774 Randomized prospective study 11 0.843 0.729 0.957 0% 0.0034 0.0581 1374 Retrospective study 32 0.884 0.846 0.922 0% 0.0004 0.0196 3314 ANOVA Q random effects test with separate estimates of T 2 P = 0.742 Total N 6462 VAS-back Prospective study 3 0.425 0.047 0.803 3% 0.0371 0.1926 284 Randomized prospective study 11 0.806 0.653 0.959 0% 0.0061 0.0780 1542 Retrospective study 15 0.715 0.587 0.843 0% 0.0043 0.0653 2560 ANOVA Q random effects test with separate estimates of T 2 P = 0.112 Total N 4386 VAS-leg Prospective study 6 0.912 0.885 0.938 0% 0.0002 0.0136 1632 Randomized prospective study 11 0.860 0.733 0.987 0% 0.0042 0.0650 1542 Retrospective study 35 0.866 0.819 0.912 0% 0.0006 0.0238 4716 ANOVA Q random effects test with separate estimates of T 2 P = 0.175 Total N 7890 ANOVA, analysis of variance; VAS, visual analog scale.
- Table 4
Analysis of effect size, heterogeneity, and ANOVA testing of difference by surgery indication.
Outcome Measure Indication for Surgery Number of Studies Included in This Analysis (Multiple Study Groups Possible) Effect Size Lower Limit Upper Limit Higgins I 2 Statistic of Heterogeneity Variance SE N Oswestry Disability Index HNP radiculopathy 8 0.920 0.862 0.977 0% 0.0009 0.0295 880 Stenosis claudication 21 0.815 0.722 0.907 0% 0.0022 0.0472 2004 ANOVA Q random effects test with separate estimates of T 2 P = 0.076 Total N patients 2884 VAS-back HNP radiculopathy 4 0.532 0.271 0.794 <1% 0.0178 0.1333 506 Stenosis claudication 14 0.694 0.514 0.874 0% 0.0084 0.0919 2780 ANOVA Q random effects test with separate estimates of T 2 P = 0.307 Total N patients 3286 VAS-leg HNP radiculopathy 8 0.868 0.769 0.966 0% 0.0025 0.0503 880 Stenosis claudication 23 0.830 0.736 0.924 0% 0.0023 0.0480 3584 ANOVA Q random effects test with separate estimates of T 2 P = 0.869 Total N patients 4464 ANOVA, analysis of variance; HNP, herniated nucleus pulposus; VAS, visual analog scale.
In this issue
Jump to section
Related Articles
Cited By...
- No citing articles found.