Lumbar Transverse Process Stress Fractures in Adolescent Athletes: A Report of Two Rare Cases.

Low back pain is one of the most frequent musculoskeletal complaints among adolescent athletes. Lumbar transverse process fractures are usually associated with high-energy trauma, such as traffic accidents and falls, and have also been reported in contact and impact sports such as football and skiing. In contrast, stress fractures of the lumbar transverse process without a traumatic episode are rare, with only a few cases described in the literature. We report two rare cases of lumbar transverse process stress fractures in adolescent athletes. A 16-year-old football player developed progressive low back pain without a history of trauma, and an MRI with magnetic resonance (MR) bone imaging revealed a stress fracture of the L3 transverse process. A 15-year-old ballet dancer presented with buttock pain, and an MRI with MR bone imaging demonstrated a fracture at the tip of the L5 transverse process. Both patients were treated conservatively with activity restriction and rehabilitation. Pain improved at around three weeks, CT at four weeks confirmed union, and return to sport was achieved at approximately eight weeks. Diagnosis can be challenging, as plain radiographs often fail to detect these fractures, while MRI and MR bone imaging enable early recognition. MRI bone imaging provides CT-like visualization of cortical bone, allowing fracture assessment while minimizing radiation exposure in adolescents. Because delayed diagnosis may lead to nonunion and chronic low back pain, awareness of this entity is essential. Lumbar transverse process stress fractures should be included in the differential diagnosis of low back pain in adolescent athletes, and prompt imaging evaluation facilitates early management and favorable return-to-sport outcomes.