Ultrasound-guided cooled radiofrequency ablation for sacroiliac joint pain in a patient with PsAPASH syndrome: A case report.

PsAPASH syndrome is a rare autoinflammatory disorder comprising psoriatic arthritis, pyoderma gangrenosum, acne, and hidradenitis suppurativa, characterized by severe cutaneous and musculoskeletal manifestations that are often refractory to systemic therapies. Sacroiliitis is a recognized feature of PsAPASH, contributing significantly to functional disability. While cooled radiofrequency ablation has emerged as an effective treatment for chronic sacroiliac joint pain, performing interventional procedures in patients with extensive active hidradenitis suppurativa poses unique challenges due to infection risk from cutaneous lesions near needle insertion sites. We report the first case of ultrasound-guided cooled radiofrequency ablation for sacroiliac joint pain in a patient with PsAPASH syndrome and extensive active hidradenitis suppurativa. A 22-year-old female with PsAPASH syndrome presented with bilateral sacroiliitis confirmed by MRI and positive provocative maneuvers, refractory to systemic biologic therapy, NSAIDs, and physiotherapy. Diagnostic intra-articular corticosteroid injections provided greater than 50% pain relief, establishing indication for definitive treatment. Due to extensive active hidradenitis suppurativa lesions near planned needle insertion sites, a multidisciplinary approach was employed involving Physical and Rehabilitation Medicine, Dermatology, and Interventional Pain specialists. Ultrasound-guided cooled radiofrequency ablation targeting the L5 dorsal ramus and S1-S2-S3 lateral branches was successfully performed with real-time mapping to avoid affected skin areas, supplemented by prophylactic antibiotic coverage. The procedure was uneventful, with no infectious or other complications. At 9-month follow-up, the patient maintained excellent pain control (mean NPRS 0, peak NPRS 2) with restoration of functional capacity. This case demonstrates that ultrasound-guided cooled radiofrequency ablation can be safely and effectively performed for sacroiliac joint pain in patients with PsAPASH syndrome, even in the presence of extensive active cutaneous disease, when appropriate multidisciplinary coordination and infection prevention strategies are employed.