E1204. Radiologic Predictors of Spinal Proximal Junction Failure/Kyphosis: What the Surgeon Wants to Know
  1. Kurren Desai; Baylor Scott & White Health
  2. Ricardo Garza-Gongora; Baylor Scott & White Health
  3. Mark Rahm; Baylor Scott & White Health
  4. Connie So; Baylor Scott & White Health
  5. Harold Sonnier; Baylor Scott & White Health
  6. Barrett Luce; Baylor Scott & White Health
  7. Krista Birkemeier; Baylor Scott & White Health
With an aging population resulting in an increase in need for elective spinal surgery, the need to reduce postoperative complications is of utmost importance. Reduction in postoperative complications results in better patient satisfaction and reduces the financial burden on the already strained healthcare system. This educational exhibit aims to discuss, define and detail radiologic predictors associated with spinal deformity surgery complications; specifically, proximal junctional kyphosis (PJK) and proximal junction failure (PJF).

Educational Goals / Teaching Points
The goal of this exhibit is to discuss the criteria and classification types of PJK/PJF. We will also highlight the risk factors radiographic parameters associated with PJK/PJF, as well as discuss the use of opportunistic CT for determining future junctional fracture or fixation loosening risk.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
We will define proximal junctional kyphosis and describe different classification systems to include those developed by Boachie-Adjei et al. and the Hart-International Spine Study Group (ISSG). Additionally, we will describe the radiographic risk factors to include the spinopelvic parameters consisting of sagittal spinal imbalance, lumbar lordosis, pelvic incidence and proximal junction angulation. Low bone mineral density is an additional risk factor; therefore, the use of opportunistic CT in assessing bone mineral density with “on-the-fly” Hounsfield unit (HU) values, and the lower cutoff HU values which correlate with poorer outcomes, will be discussed. Finally, we will provide a guideline for preoperative radiographic assessment and postoperative radiographic goals for prevention of PJK/PJF.

Although PJK is often asymptomatic, PJF is a serious complication associated with adult spinal deformity surgery. By understanding the pathophysiology of PJF and defining the radiographic assessment for surgical prophylactic prevention, we can reduce the need for revision surgery to ultimately improve patient outcomes and ease the financial burden on the healthcare system.