ADIPOSE-DERIVED MESENCHYMAL STEM CELLS TRANSPLANTATION FOR GENERATOR POCKET PAIN IN SPINAL CORD STIMULATION: A CASE REPORT

L. Villagrossi, Al. Martin, P. Vendramin, E. Bonora, A. Patton, G. Poni, L. Occhial, M. Tomasi, N. Pozzobon, E. Polati, V. Schweiger | Department of Anesthesia, Intensive Care and Pain Therapy, Verona University Hospital

BACKGROUND
Generator Pocket Pain (GPP) is defined as a localized pain over the implantable pulse generator (IPG) in patients with spinal cord stimulation (SCS). Despite SCS being effective for chronic pain, GPP is an underestimated complication, with reported incidence ranging from 1% to 64%. Risk factors include female sex, low BMI, smoking, and psychiatric comorbidities. Conservative treatments (medications, local injections, physical therapy) often prove ineffective in persistent cases, leaving surgical options (repositioning or removal) as the only viable alternatives. To date, no standardized guidelines or alternative biological therapies for GPP exist.
CASE PRESENTATION
In January 2021, after our first evaluation, a 62-year-old man with a history of bilateral lumbosciatica following spinal trauma and multiple lumbar surgeries was diagnosed with Post-Surgical Pain Syndrome II (PSPS II). The patient showed a significant impact of pain in his daily life, with a Quality-of-Life score (QoL 0-100) of 20%, a VAS score (Visual Analogue Score 0-100) of 90 and an Oswestry Disability Index (ODI 0-100) of 42. Following inadequate pain control with high-dose medications and invasive procedures (like epidural steroid injections, Pulsed Radiofrequency of the Dorsal Root Ganglion of L4-L5 and epiduroscopy with direct adesiolysis), in august 2021 he underwent SCS implantation with a Boston Scientific WaveWriter AlphaTM device. The system included two octopolar leads at T8 and an IPG placed in the right gluteal pocket. After two months, the patient referred significant improvement in QoL (from 20 to 80%), VAS (from 90 to 30) and ODI (from 42 to 36) and was very satisfied of the analgesic result of SCS. However, in May 2023, the patient developed intense, stabbing pain (NRS 10/10) localized to the IPG site, severely affecting sitting and quality of life. NSAIDs and 5% lidocaine were ineffective. A novel approach was proposed: infiltration of autologous adipose-derived mesenchymal stem cells (AD-MSCs) into the pocket. In June 2025, 60 ml of abdominal fat was harvested, processed with the Lipo-Stem Duo™ system, and 30 ml of MSC-rich material was injected into the gluteal pocket under sterile conditions and local anesthesia.
RESULTS
The procedure was well tolerated, with no adverse events. The patient reported a marked improvement in pain intensity and frequency immediately after the injection (NRS 2/10). Follow-up is ongoing to monitor long-term efficacy.
CONCLUSIONS
This is, to our knowledge, the first report describing the use of autologous AD-MSCs for treating GPP. Given the absence of established treatment algorithms and the failure of conventional therapies, MSC-based interventions may offer a safe and effective alternative. Their known anti-inflammatory and tissue-modulating properties suggest a rationale for use in mechanically induced, localized neuropathic pain. Further research is needed to validate these findings and explore broader clinical applications.