Inclusion criteria and types of operation of included studies.
| Authors | Inclusion Criteria | No. of Vertebral Levels | Types of Operation | |
| Decompression Alone | Decompression + Fusion | |||
| Austevoll 20202 | Diagnosed both spinal stenosis and spondylolisthesis, and then operated with decompression or with decompression + fusion | 1–2 | Microdecompression with midline preservation | Instrumented fusion |
| Chan 20194 | Diagnosed grade one spondylolisthesis, and then underwent posterior-only surgery at the index level of lumbar spondylolisthesis (decompression alone or fusion with or without decompression), or underwent single-segment surgery (single-level disc decompression [eg, L4 or L4–five decompressive laminectomy]) or a 2-level vertebral fusion (eg, L4–five posterior spinal fusion) | 1 | Laminectomy | Instrumented fusion |
| Försth 201316 a | Aged >50 y at the time of surgery, diagnosed spinal stenosis on 1–2 adjacent levels between L2 and L5, with or without spondylolisthesis, and then operated with decompression or with decompression + fusion | 1–2 | Decompression | Instrumented or noninstrumented fusion |
| Försth 20166 a | Aged between 50 and 80 y, diagnosed spinal stenosis on 1–2 adjacent levels between L2 and sacrum, with or without spondylolisthesis, symptomatic (pseudoclaudication in one or both legs and back pain [VAS > 30]) for >6 mo, and then operated with decompression or with decompression + fusion | 1–2 | Decompression | Instrumented or noninstrumented fusion |
| Ghogawala 20047 | Aged between 50 and 81 y, diagnosed grade one spondylolisthesis, and then operated with decompression or with decompression + fusion | - | Decompression with aggressive facet-sparing technique | Posterolateral instrumented fusion |
| Ghogawala 20168 | Aged between 50 and 81 y, diagnosed stable grade one spondylolisthesis with spinal stenosis, symptomatic (neurogenic claudication with or without lumbar radiculopathy), and then operated with decompression or with decompression + fusion | 1 | Complete laminectomy with partial removal of medial facet joint | Posterolateral instrumented fusion |
| Inose 20183 | Diagnosed spinal stenosis on one level at the L4-5, with spondylolisthesis, and then operated with decompression or decompression + fusion or decompression + stabilization | 1 | Decompression | Posterolateral instrumented fusion with autogenous iliac bone graft and pedicle screw |
| Kim 20189 | Diagnosed grade one spondylolisthesis at L4-5, symptomatic, and then operated with decompression or with decompression +fusion | - | Decompressive laminectomy, partial facetectomy, <50% of the inferior articular processes in the transverse dimension, foraminotomy according to the extent of radiculopathy, with both facet joints preserved | Circumferential fusion with pedicle screws, posterolateral fusion with autogenous iliac bone graft, and posterior lumbar interbody fusion using a titanium cage filled with a local bone graft |
| Kleinstueck 201110 | Diagnosed spondylolisthesis with a maximum of 3 levels affected, and then operated with decompression or with decompression + fusion | 1–3 | Decompression | Instrumented fusion |
| Matsudaira 200511 | Diagnosed both spinal stenosis and spondylolisthesis on single level at L4/5, and then operated with decompression or with decompression + fusion | 1 | Laminoplasty to preserve the integrity of midline structure | Posterolateral fusion and pedicle screw instrumentation |
| Park 201212 | Diagnosed stable grade one spondylolisthesis, and then operated with decompression or with decompression + fusion | 1 | Laminectomy | Instrumented fusion |
| Sigmundsson 201513 | Diagnosed both spinal stenosis and spondylolisthesis on single level, and then operated with decompression or with decompression + fusion | 1 | Decompression | Posterolateral instrumented fusion |
| Ulrich 201715 | Diagnosed both spinal stenosis and spondylolisthesis, and then operated with decompression or with decompression + fusion | 1–2 | Standard open or microscopic decompression of the lateral recess and the foramina | Implantation of pedicle screws with rods and intersomatic fusion and cage(s) at the affected level(s) |
aOnly patients with spondylolisthesis were included in the analysis.