Introduction: Proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) are well-described adverse outcomes following long segment instrumented fusions for spinal deformities. There is a lack of consensus regarding which patients require revision surgery. Recently, the Hart ISSG PJK severity scale was shown to correlate with the need for revision surgery. This study evaluates whether the Hart ISSG PJK severity scale is correlated with quality of life measures in patients with PJK.
Methods: All adult spinal deformity patients with PJK and/or PJF who underwent revision surgery were identified from two academic centers. Patients were retrospectively assigned scores based on the Hart ISSG PJK severity scale. Pre PJK revision health related quality of life (HRQOL) measures were prospectively collected: Oswestry Disability Index, SF-36 components, and SRS30 components. Correlation of Hart ISSG PJK severity scale and HRQOL outcomes was assessed with a Pearson correlation coefficient.
Results: 54 cases were included. 31.5% were male and mean age was 64.9 years. Scores ranged from 4 to 15, with the median being 8. PJK/PJF occurred in the upper thoracic spine in 24.1% of the cases. 54.8% had fractures and 77.8% had instrumentation issues. 55.6% had neurological deficits, with 16.7% having weakness and/or myelopathy. All patients had pain preoperatively (median VAS score was 9 of 10). While statistical significance on linear regression was not seen, there were obvious trends that correlated with the Hart ISSG PJK severity scale. Higher Hart ISSG PJK severity scale scores were associated with higher ODI (p = 0.283, r = 0.350), lower SRS30 function (p=0.821, r = -0.323), and lower SRS mental (p= 0.646, r = -0.592).
Conclusions: The Hart ISSG PJK severity scale is predictive in deciding when patients are considered for revision surgery, and based on the current study it may also correlate with functional outcomes, specifically ODI and SRS30 components.
Patient Care: The Hart ISSG PJK severity scale may act as a reproducible quantitative measure that can guide clinical decision making in patients with PJK and PJF.
Learning Objectives: 1. Recognize the incidence and significance of PJK and PJF follow long-segment instrumentation
2. Describe the correlation of the Hart ISSG PJK severity score with clinical outcomes
3. Apply the Hart ISSG PJK severity scale to patients with PJK and PJF