188. ‘Soft landing’: can hooks at the upper instrumented level prevent proximal junctional kyphosis and proximal junctional failure in adult spinal deformity?

Abstract

BACKGROUND CONTEXT Proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) are a well-recognized, yet incompletely defined, complication of adult spinal deformity surgery. There is no standardized definition for PJK, but most studies describe PJK as an increase in the proximal junctional angle (PJA) of greater than 10°–20°. “Soft landing” is a novel strategy for PJK reduction by creating a gradual transition from a rigid segmental construct to the native spine at the top of the construct while reducing junctional stress at those levels. PURPOSE To determine if the “soft landing strategy, when applied in adult spinal deformity, will decrease the rate of PJF. STUDY DESIGN/SETTING Retrospective consecutive series. PATIENT SAMPLE Thirty-six consecutive series of adult spinal deformity patients at a single institution. OUTCOME MEASURES Rate of proximal junctional failure (PJF). METHODS In this study, “soft landing” was used in a 36 consecutive series of adult spinal deformity patients at a single institution. Patient demographics, including age, sex, indication for surgery, revision surgery, surgical approach and use of osteotomies and vertebroplasty were collected. The PJA, global sagittal alignment (TPA, SVA) and spinopelvic parameters (PI,PT,SS) were measured preoperatively and at last follow-up using 36-inch radiographs. Data on change in PJA and need for revision surgery were collected. Univariate and multivariate analyses were performed to identify factors associated with change in PJA and proximal junctional failure (PJF), defined as PJK requiring surgical correction. RESULTS A total of 36 consecutive patients were included: The mean age of the cohort was 60 years, and 92% of patients were women. Over half of these cases (58%) were revision surgeries, with 67% involving a combined anterior or lateral and posterior approach. The mean change in PJA was 11.4°; 22 patients had a change of less than 10°. Thirteen patients had a change in PJA of 10°–20°, and 1 patient had a change in PJA of greater than 20°. Reoperation was performed in 8 cases (22%); however, only 2 (∼6%) were for PJF. CONCLUSIONS Our study demonstrates the “soft landing strategy decreases the rate of PJF, with only 6% of cases requiring reoperation for a structural failure. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.