Proximal Junctional Kyphosis in Adult Spinal Deformity Following Long Instrumented Posterior Spinal Fusion

To determine the incidence of PJK and its effect on patient outcomes and to identify any risk factors associated with developing PJK. SUMMARY OF BACKGROUND DATA: The incidence of PJK and its affect on outcomes in adult deformity patients is unknown. No study has concentrated on outcomes of patients with PJK. Risk factors for developing PJK are unknown.

Radiographic data on 81 consecutive adult deformity patients with minimum 2-year follow-up (average 5.3 years, range 2-16 years) treated with long instrumented segmental posterior spinal fusion was collected. Preoperative diagnosis was adult scoliosis, sagittal imbalance or both. Radiographic measurements analyzed included the sagittal Cobb angle at the proximal junction on preoperative, early postoperative, and final follow-up standing long cassette radiographs. Additional measurements used for analysis included the C7-Sacrum sagittal plumb and the T5-T12 sagittal Cobb. Postoperative SRS-24 scores were available on 73 patients.