An Ultrasound Image-and-Intervention Paradigm for a Neglected Lumbar Transverse Process Fracture: A Case Report of Diagnosis and Hydrodissection Treatment.

Lumbar transverse process (TP) fractures are often overlooked, leading to chronic pain that is frequently refractory to standard treatments. This case report describes the diagnostic use of musculoskeletal ultrasound (MSK-US) and a novel therapeutic application of ultrasound-guided hydrodissection for a case of neglected TP stress fracture. A 41-year-old male presented with an 18-month history of chronic right groin and thoracolumbar pain, unresponsive to extensive prior treatments, including physical therapy, medications, and multiple nerve blocks. MSK-US confirmed a cortical irregularity and step-off deformity at the left L2 TP, with sonoguided digital palpation precisely localizing the source of his symptoms. An ultrasound-guided hydrodissection procedure was performed using 5% dextrose in water (D5W) to address suspected neurovascular entrapment. The patient reported an immediate 80% reduction in resting pain following the procedure. After two additional weekly sessions, he achieved a sustained 95% pain reduction and complete resolution of physical examination deficits. Follow-up imaging demonstrated evidence of bony healing. This case highlights MSK-US as a pivotal diagnostic tool for elusive chronic TP fractures and introduces ultrasound-guided hydrodissection as a novel, minimally invasive therapeutic strategy. This "image-and-intervene" paradigm effectively provided rapid pain relief, functional restoration, and facilitated a healing environment, offering a promising approach for managing similar refractory chronic pain conditions.