INTRA-VERTEBRAL INSTABILITY WITH PARAPARESIS AFTER KYPHOPLASTY FOR A STABLE OSTEOPOROTIC FRACTURE WITH ADJACENT HEALED FRACTURES

Abstract

Introduction: Kyphoplasty, an established low-risk procedure for the management of symptomatic osteoporotic fractures, has been a topic of debate due to doubts regarding its efficacy and its associated complications like adjacent segment fractures and cement leakage. We present a unique case of failure of kyphoplasty due to dynamic instability through the vertebral body in a patient with a recent onset osteoporotic fracture treated by double-balloon kyphoplasty. To the best of our knowledge, there are no reported cases of dynamic instability with paraparesis after kyphoplasty for a fresh stable osteoporotic fracture associated with adjacent multiple healed osteoporotic fractures. Case Presentation: A 78-year-old female with complaints of back pain and imaging suggestive of old osteoporotic fractures of T12 and L1 vertebra with a fresh stable osteoporotic fracture L2 vertebra was treated with kyphoplasty after the failure of conservative treatment. After an initial good response, the patient started complaining of back pain and anterior thigh pain with weakness in both lower limbs. Dynamic X-rays and MRI of the patient revealed intra-vertebral instability at the L2 level. The patient was operated with interbody fusion L1–L2 and posterior stabilization L1–L3, and co-existing L5–S1 spondylolisthesis was dealt with by postero-lateral fusion L5–S1. Discussion: Recurrence of back pain after kyphoplasty can be caused by re-fracture at the same level or adjacent vertebral fracture. Neurological complications are rarely reported after balloon kyphoplasty and are mostly related to cement leakage into the spinal canal. The old adjacent segment fractures altering the biomechanics with resulting undue stress on the augmented stiff vertebra may have resulted in intra-vertebral instability and paraparesis. In balloon kyphoplasty, cement is put in the anterior part of the vertebral body and the posterior body lacks support. This may also have contributed to instability. Conclusion: Dynamic instability at the intra-vertebral level can be a cause of failure of kyphoplasty especially when adjacent osteoporotic fractures are altering the biomechanics of the spine. The treatment of osteoporotic fractures should be individualized and in the presence of such factors, they may be better managed by alternative methods.