Injection of processed cells from a patient’s own fat into the spine for adults with chronic degenerative low back pain: effect on 12-month pain intensity

The intervention is a single administration of autologous stromal vascular fraction (SVF; E2Spine) prepared from the participant’s own adipose tissue. On Day 0, approximately 100–150 mL of adipose tissue is harvested by standardised tumescent mini-liposuction from a suitable donor site, such as the abdomen, flank, back, or thigh. The lipoaspirate is processed on-site under aseptic conditions using a standardised mechanical, non-enzymatic method based on StroMed ultrasonic cavitation to isolate SVF. The prepared SVF is suspended in Plasma-Lyte and administered under fluoroscopic image guidance to the target lumbar functional spinal unit. Administration includes intradiscal injection into the index intervertebral disc, peri-radicular application adjacent to the symptomatic nerve root, and injection into the ipsilateral facet joint(s), as clinically indicated and within protocol-defined anatomical limits. Intradiscal delivery is performed slowly using a pressure-monitored syringe system, with continuous monitoring of injection resistance, intradiscal pressure, and participant symptoms. Injection is paused or discontinued if excessive resistance, marked pressure rise, vascular uptake, radicular symptoms, or significant discomfort occurs. The total injection period for each target site is expected to be brief and should not exceed approximately 5 minutes per site, excluding needle placement, confirmation, and any dwell period. The target SVF dose is 40 × 106 viable nucleated cells for the index disc, 5 × 106 viable nucleated cells for the peri-radicular region at the index level, and 10 × 106 viable nucleated cells per ipsilateral facet joint, up to two facet joints. Approximate injection volumes are 0.8 mL intradiscally, 0.2 mL peri-radicularly, and 0.4 mL per facet joint, with a maximum total facet injection volume of 0.8 mL. Following intradiscal SVF delivery, the needle may be maintained in position for approximately 3–5 minutes to minimise reflux, and TISSEEL fibrin sealant is administered separately through the same tract as a protocol-defined adjunct to reduce egress from the annular puncture or fissure pathway. Rescue medication is permitted according to protocol-defined criteria where pain is inadequately controlled or clinically significant pain flare occurs. Participants are encouraged to maintain stable background analgesic therapy where possible to minimise confounding. Short-term additional analgesia may be used when clinically necessary, and all rescue medication use, including medication type, dose, timing, duration, and indication, will be recorded. High-dose NSAIDs should be avoided during the first 72 hours after the procedure unless clinically required.