Outcomes of Microendoscopic Discectomy and Percutaneous Transforaminal Endoscopic Discectomy for the Treatment of Lumbar Disc Herniation: A Comparative Retrospective Study

Study DesignRetrospective, case control evaluation of 86 patients who underwent microendoscopic discectomy (MED) and percutaneous transforaminal endoscopic discectomy (PTED) for the treatment of lumbar disc herniation (LDH).PurposeTo evaluate the safety and the outcomes of MED and PTED for the treatment of LDH.Overview of LiteratureMED and PTED are minimally invasive surgical techniques for lower back pain. Studies to date have shown that MED and PTED are safe and effective treatment modalities for LDH.MethodsA retrospective study was performed in patients with LDH treated with MED (n=50) and transforaminal endoscopic discectomy (PTED; n=36) in our hospital. All patients were followed-up with self-evaluation questionnaires, Oswestry disability index (ODI), medical outcomes study 36-item short form health survey and MacNab criteria. All the patients in both groups were followed up to 12 months after the operation.ResultsODI questionnaire responses were not statistically different between the MED and PTED groups (53.00 vs. 48.72) before treatment. Average scores and minimal disability after 5 days to 12 months of follow-up were 4.96 in the MED group and 3.61 in the PTED group. According to MacNab criteria, 92.0% of the MED group and 94.4% of the PTED group had excellent or good results with no significant difference.ConclusionsThere was no significant difference between MED and PTED outcomes. Further large-scale, randomized studies with long-term follow-up are needed

Nucleus Pulposus Cell Conditioned Medium Promotes Mesenchymal Stem Cell Differentiation into Nucleus Pulposus-Like Cells under Hypoxic Conditions

Low back pain (LBP) is a major physical and socioeconomic challenge worldwide. Nucleus pulposus (NP) is directly associated with LBP due to intervertebral disc (IVD) degeneration. IVD degeneration is mainly caused by structural and matrix-related changes within the IVD occurring during aging and degeneration. Mesenchymal stem cells (MSCs) can differentiate into multiple mesenchymal lineages under specific stimulatory conditions. This study is aimed at evaluating the effectiveness of the nucleus pulposus cell (NPC) conditioned medium for promoting the expression of MSCs and at confirming the expression of healthy NP phenotypic markers recently recommended by the Spine Research Interest Group. Expression was investigated using quantitative polymerase chain reaction (qPCR) and western blotting under normoxic and hypoxic conditions. qPCR and western blotting demonstrated significant upregulation of NP marker expression in MSCs cultured under hypoxic conditions and treated with the 50% or 100% NPC conditioned medium, compared with those cultured under normoxic conditions. Upregulation was highest in the presence of the 100% NPC conditioned medium compared with the control group (aggrecan, p<0.01; brachyury, p<0.05; collagen II, p<0.001; KRT8, p<0.01; KRT19, p<0.001; and Shh, p<0.01). The expression levels of genes in MSCs treated with the 50% NPC conditioned medium also showed upregulation compared with the control group (collagen II, p<0.05; KRT8, p<0.05; and KRT19, p<0.01). These findings suggested that the NPC conditioned medium stimulated MSC differentiation into an NP-like phenotype with distinct characteristics. The results could inform strategies for IVD regeneration