Trigger point injection (TPI) is commonly administered for myofascial pain syndrome management, but occasionally leads to complications, including bleeding, muscle hematoma, vasovagal syncope, skin infections, and pneumothorax. This report presents a case of TPI-induced iatrogenic spinal cord injury (SCI). A 59-year-old woman received TPI for myofascial pain on both thoracolumbar paraspinal muscles. She experienced an electric shock sensation throughout the lower extremities upon receiving blind TPI in the left thoracolumbar paraspinal muscle, and later complained of weakness (manual muscle test grade: 0-2) and neuropathic pain (numeric rating scale [NRS]: 7) in the lower left extremity. Thoracolumbar magnetic resonance imaging (MRI) 3 days after the TPI revealed a high-intensity T2 signal in the left T12 to L2 spinal cord segments, indicating the presence of edema or inflammation in this region. In concordance with the MRI findings, electrophysiological recordings performed 11 days after the TPI revealed no central motor conduction time response in the left leg. At 7 months post-onset, the patient had partially recovered motor function and neuropathic pain was reduced to NRS 4. Clinicians should be aware of the possibility of needle-induced SCI during paraspinal muscle TPI; imaging guidance may be helpful for accurate needle targeting during the procedure.
Keywords: Trigger point injection; iatrogenic injury; motor weakness; myofascial pain syndrome; paraspinal; spinal cord injury.