Table 3. Summary of studies that performed a comparative analysis of surgical versus non-surgical management .

No.	Article title	Authors	Journal of publication	Year of publication	Main findings
1.	The Maine Lumbar Spine Study, Part III: 1-Year Outcomes of Surgical and Nonsurgical Management of Lumbar Spinal Stenosis [23]	Atlas SJ, Deyo RA, Keller RB, Chapin AM, Patrick DL, Long JM, Singer DE	Spine	1996	This trial involved 148 patients with spinal stenosis: 81 were surgically treated, while the remaining were given conservative therapy. Most patients undergoing surgery had severely intense pain and other symptoms, while the majority of patients treated conservatively experienced mild to moderate symptoms. At one-year follow-up, 55% of the patients treated surgically demonstrated improvement when compared to the 28% managed conservatively. This difference remained statistically significant even after adjustments were made for initial symptom severity.
2.	Surgical and Nonsurgical Management of Lumbar Spinal Stenosis: Four-Year Outcomes From the Maine Lumbar Spine Study [24]	Atlas SJ, Keller RB, Robson D, Deyo RA, Singer DE	Spine	2000	Out of a total of 148 patients with lumbar spinal stenosis, 119 patients were compared for their prognosis after a period of four years. Sixty-seven were surgically intervened, and 52 were treated non-invasively. After a four-year follow-up, the patients that underwent surgical intervention demonstrated significantly improved pain status (70% > 52%). More than 60% of the surgical patients were satisfied with their current health status, while ~40% of patients treated non-surgically felt the same.
3.	A Prospective Randomized Multi-center Study for the Treatment of Lumbar Spinal Stenosis With the X STOP Interspinous Implant: 1-year Results [25]	Zucherman JF, Hsu KY, Hartjen CA, et al.	European Spine Journal	2004	In this study, researchers used an interspinous spacer device (X STOP implant) for 100 spinal stenosis patients, whereas 91 subjects were treated conservatively. The Zurich Claudication Questionnaire (ZCQ) was used as a data collection and analysis tool. X STOP implant therapy showed a high improvement rate of >50%, while the control group showed a 10% success at six weeks post-treatment. Similar results were obtained at six and 12 months' follow-up.
4.	Surgical or Nonoperative Treatment for Lumbar Spinal Stenosis?: A Randomized Controlled Trial [26]	Malmivaara A, Slätis P, Heliövaara M, et al.	Spine	2007	This randomized controlled trial consisted of 94 patients suffering from lumbar spinal stenosis: 53.2% (50 patients) underwent laminectomy and fusion surgery. The remaining 44 were treated conservatively. The Oswestry Disability Index was utilized to compare the post-treatment status of patients. In subsequent follow-up sessions, the patients treated surgically demonstrated decreased disability, lower limb pain, and back pain. However, the walking ability improved equally in both groups.
5.	The Preliminary Results of a Comparative Effectiveness Evaluation of Adhesiolysis and Caudal Epidural Injections in Managing Chronic Low Back Pain Secondary to Spinal Stenosis: A Randomized, Equivalence Controlled Trial [27]	Manchikanti L, Cash KA, McManus CD, Pampati V, Singh V, Benyamin R	Pain Physician	2009	The authors divided patients into two groups with 25 patients each (total = 50). One group was given epidural injections with a mixture of local anesthetic, isotonic NaCl (0.9%) solution, and betamethasone. The other group received hypertonic (10%) saline, betamethasone, and lidocaine injection. This experimental group also underwent adhesiolysis. Follow-up analysis resulted in pain control in approximately 76% cases of the intervention group compared to 4% of the control group population.
6.	Surgical versus Non-Operative Treatment for Lumbar Spinal Stenosis Four-Year Results of the Spine Patient Outcomes Research Trial (SPORT)[28]	Weinstein JN, Tosteson TD, Lurie JD, et al.	Spine	2010	The study performed a comparison of surgical laminectomy versus non-invasive treatment strategies. A total of 289 patients were included in the randomized group, while 365 patients were recruited to the observational cohort. The results of the study showed improved function in surgically treated patients, even at four years postoperatively.
7.	A Double‐blind, Randomized, Prospective Study of Epidural Steroid Injection vs. The MILD ® Procedure in Patients with Symptomatic Lumbar Spinal Stenosis [29]	Brown LL	Pain Practice	2012	In this study, 38 patients underwent intervention for lumbar spinal stenosis. Twenty-one were surgically treated for spinal decompression (MILD procedure), while the other 17 underwent epidural steroid injection therapy. At follow-up, surgically intervened patients demonstrated greater improvement with respect to overall functional status and a decrease in pain intensity.
8.	Effects of Transforaminal Balloon Treatment in Patients With Lumbar Foraminal Stenosis: A Randomized, Controlled, Double-blind Trial [30]	Kim SH, Choi WJ, Suh JH, et al.	Pain Physician	2013	A total of 62 patients were randomized and treated with either steroid injections with transforaminal balloon intervention or with transforaminal injections alone. The first group demonstrated better post-intervention results when compared to the latter. Nearly 20% of cases in the balloon therapy group maintained their pain-free status after one year, as compared to 0% in the other group.
9.	Surgery Versus Nonsurgical Treatment of Lumbar Spinal Stenosis [31]	Delitto A, Piva SR, Moore CG, et al.	Annals of Internal Medicine	2015	In this project, 169 patients with spinal stenosis patients were split into two groups: 87 were treated surgically and 82 were treated with physiotherapeutic interventions. Upon follow-up analysis, patient functional status was improved in a total of 22.4% of patients who underwent surgery, compared to 19.2% patients who underwent physiotherapy. No statistically significant differences were seen between the two groups.