Considerations for repetitive intrathecal procedures in long-term nusinersen treatment for non-ambulatory spinal muscular atrophy

Spinal muscular atrophy (SMA) is a progressive neuromuscular disorder characterized by progressive motor function loss and skeletal muscular atrophy. Nusinersen, an antisense oligonucleotide, is the first FDA-approved therapy to achieve a significant milestone in SMA management. However, its high molecular weight requires intrathecal administration, posing challenges for clinical implementation. This study aimed to identify factors associated with postprocedural pain following repeated CT-guided transforaminal nusinersen injection in non-ambulatory patients with SMA. This single-center retrospective study evaluated 34 patients who underwent a total of 290 procedures. Postprocedural pain occurred in 49.3% of cases. Factors influencing postprocedural pain included needle angle with vertical and horizontal lines, prophylactic pain control, and number of CT scans (p < 0.05). In patients experiencing postprocedural pain, the needle angle with vertical and horizontal lines emerged as significant variables, with a beta coefficient (standard error) of 0.034 (0.011) (p < 0.05). Needle angle was an important predictor of postprocedural pain.