Comparison of Lumbar Paraspinal Muscle Injury and Early Degeneration Between Endoscopic Lumbar Interbody Fusion Versus Transforaminal Lumbar Interbody Fusion: A Retrospective Study

Objective The clinical efficacy and minimal invasiveness of endoscopic lumbar interbody fusion (Endo-LIF) for lumbar degenerative diseases (LDD) was frequently reported in previous studies. However, there is no existing literature regarding quantitative measurement of lumbar paraspinal injury following the surgery. The study was to quantitatively investigate early outcomes of lumbar paravertebral muscle between Endo-LIF and transforaminal lumbar interbody fusion (TLIF) for single level lumbar spinal stenosis (LSS). Methods In this retrospective cohort study, 90 patients with severe LSS, who received one-level lumbar decompression and fusion were enrolled to two groups: group 1 (n = 48) underwent Endo-LIF procedure and group 2 (n = 42) received TLIF procedure. The surgery-related parameters, functional status including Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS), laboratory indicators including serum creatine kinase (CK), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were collected as indicators for muscle trauma. Paraspinal muscle measurements were performed at the instrumented intervertebral lacunae on magnetic resonance imaging (MRI). Results Fluoroscopy times and duration of operation were significantly higher in Endo-LIF group than those of TLIF group (P < 0.01). Endo-LIF group showed better ODI and VAS for back score improvement 3 days post-surgery (P < 0.01). There was no significant difference in ODI and VAS between two groups at early follow-up (P = 0.95, P = 0.08, P = 0.38 respectively). CK and CRP increased higher in TLIF group postoperatively compared to Endo-LIF group (P < 0.01). ESR showed no statistical significance between two groups regarding ESR before and one-day post-operation (P = 0.06). The MRIs at early follow-up revealed a statistically significantly less paraspinal muscle atrophy in Endo-LIF group than that in TLIF group. Conclusions The study revealed lumbar paraspinal muscle in patients of Endo-LIF group showing less damage postoperatively and lighter amyotrophy at early follow-up based on the laboratory and radiological results. Trial registration Registered at Chinese Clinical Trial Register on February 2nd 2021.