Targeted Iliolumbar Ligament Cryoanalgesia Relieves Bertolotti Syndrome Pain: Recent Clinical Report Finds
A recent case report reveals that targeting the bony attachments of the iliolumbar ligament with cryoanalgesia delivers powerful, lasting relief for Bertolotti syndrome. By freezing these specific nerve-rich connection points, clinicians achieved sustained pain control where conventional therapies failed.
The report was published in June 2026 in the Indian Journal of Pain by Dr. Ken-Yi Lui and colleagues at the University Health Network in Toronto.
Clinical Case Presentation
A 36-year-old woman presented with persistent, intractable left-sided low back pain secondary to type IIa Bertolotti syndrome, characterized by partial sacralization of the left L5 transverse process. Prior conservative and interventional modalities—including multimodal oral analgesics, physical therapy, sacroiliac joint infiltrations, interlaminar epidural corticosteroids, peripheral nerve blocks, and lumbar facet radiofrequency neurotomy—had failed to provide sustained clinical relief.
Diagnostic local anesthetic infiltration confirmed the iliolumbar ligament as the primary pain driver by providing complete relief for three days. Although multi-tined radiofrequency ablation of the ligament body yielded only brief analgesia returning to baseline within five weeks, switching to cryoanalgesia produced 30% to 50% pain reduction lasting four months. The interventionalists then refined their technique by applying circumferential cryolesions directly above and below the ligament’s bony attachments at the L5 transverse process and the ilium rather than on the ligament midsection. This enthesial approach eliminated pain within one week without an initial procedural flare, maintaining 75% relief at six weeks and 50% at five months while allowing progressive physical rehabilitation. Subsequent repeat treatments sustained these gains, ultimately providing 80% pain relief and preserved functional capacity through the 12-month follow-up.
Mechanistic Insights
Transitional lumbosacral vertebrae impose abnormal biomechanical stresses across adjacent intervertebral discs and the underdeveloped iliolumbar ligament on the affected side. Histological investigations demonstrate that while the dense fibrous mid-substance of the ligament is completely aneural, high concentrations of free nociceptive nerve endings and mechanoreceptors populate its osseous insertions and adjacent fibrofatty tissue.
Conventional ablation targeting the ligament body therefore misses critical sensory inputs. By concentrating ice ball formation at both enthesial interfaces, cryoanalgesia disrupts peripheral pain transmission while maintaining connective tissue architecture. This preservation avoids post-procedural neuritis and soft-tissue necrosis seen with thermal techniques.
Implications for Clinicians
Clinicians evaluating refractory low back pain associated with lumbosacral transitional anomalies should recognize the iliolumbar enthesis as an underappreciated, viable therapeutic target. Rather than applying indiscriminate thermal ablation along the ligament midsection, interventionalists should focus on bilateral osseous attachment denervation. Cryoanalgesia provides extended pain relief while preventing tissue destruction, establishing an invaluable therapeutic window for patients to engage in progressive core reconditioning.
Reference
Lui, K.-Y., Assavanop, S., Alomari, A., & Peng, P. W. (2026). Treatment of Bertolotti Syndrome: From concept to denervation. Indian Journal of Pain, 40(2), 118–121.
