29. Complete Healing of Traumatic Multiple Spinal Fractures in a Patient with Ankylosing Spondylitis Who Refused Surgical Intervention with Teriparatide

Abstract

Background: Spinal fractures in patients with AS carry higher rates of morbidity and mortality compared with healthy subjects. Some of the associated risk factors include inflammation of the spine leading to abnormal posture and osteoporosis. Cervical fractures in AS patients, are associated with significant risk of neurological complications, subsequently their management is complex. The usual recommended treatment is prompt surgical fixation to achieve fracture reduction and healing with minimum loss of mobility. Conservative immobilization with halo orthosis carries a very high rate of pseudo-arthrosis. Regardless of the approach, there remains a significant risk of non-union. Methods: We report a case of a 50 year old Caucasian gentleman with an established 20 years diagnosis of AS, currently enrolled in clinical trial of IL 17 inhibition, who sustained undisplaced fractures across the C5 and T2 vertebral bodies, following a traumatic hyperextension injury. An urgent C2-T5 fixation surgery was recommended by spinal surgeons. However, he refused, fearing the possible complications of the procedure; he therefore opted for conservative treatment. A bone densitometry scan showed no evidence of osteoporosis (spinal T score -0.6). Nonetheless, with the view of accelerating bone healing, we commenced him on s.c. teriparatide (PTH 1-34) at a dose of 20mg daily for period of 6 months. Results: His pain gradually subsided and he was pain free 2 months into the treatment. He underwent a further CT scan which confirmed complete healing at 6 months without any complications. Conclusion: Teriparatide, well established as a treatment for severe post-menopausal osteoporosis, is an agent with anabolic effect on bone metabolism through enhancing of osteoblast proliferation. Other reported successful off-label use of Teriparatide include: acceleration of healing in surgical failures of cervical and femoral fractures in subjects without AS, achieving successful healing of sacral insufficiency fractures and reduction of the rate of new-onset adjacent vertebral compression fracture following percutaneous vertebroplasty. The use of Teriparatide in AS patients with cervical fracture following failure of the surgical intervention has been reported recently. However, our case is unique as complete healing of the fracture was achieved without complication and without the assistance of surgical intervention. We, therefore, recommend further study and extension of Teriparatide use in spinal fractures in patients with AS.