gms | German Medical Science

Objective: Spinal cord stimulation (SCS) and intrathecal drug delivery are important methods for treating patients with chronic pain. Both have been established as safe and effective methods leading to remarkable pain easement. Though complications are rare they might lead to serious neurological deficits that may require further surgical interventions.

Method: The case of a 59-year-old female patient with a history of chronic right inguinal pain is reviewed. After several external operations we implanted a spinal cord stimulator and thereafter a drug pump for intrathecal morphine delivery. 15 years after the initial implantation and having underwent multiple surgeries due to complications (i.e. Infections, electrode migration, etc) the patient presented to our clinic with a slow onset of paraparesis and a sensitive deficit below the level of Th-10. MRI imaging revealed an epidural formation causing compression of the spinal cord at the level of T-8 reaching up to T-10 at the tip of the spinal cord stimulation electrode. Neurosurgical intervention was required. Surgically the spinal canal was approached through a left inter-laminar approach at the level of the 8^th, 9^th and 10^th thoracic vertebrae. After removing large quantities of fibrous tissue, the dura mater was visualized and complete resection of the mass was achieved. The mass was solely epidural.

Results: Histological examination demonstrated a granuloma. After neurosurgical intervention, the patient improved neurologically. SCS showed good function and daily morphine dose could be decreased. Follow-up after six months year showed a fully neurological recovery.

Conclusions: Spinal cord stimulation and intrathecal drug delivery systems might provoke the formation of epidural and intrathecal formations (i.e. granuloma) that can lead to spinal cord compression causing neurological deficits. This is a rare but serious complication that should be well known among physicians delivering this treatment.