Long-Fusion Surgery for Elderly Patients with ASD

The study protocol was approved by the institutional review board at each site. Informed consent was obtained from all patients. We retrospectively documented the data of ASD patients in two hospitals from January 2018 to December 2019, aiming to have a minimum follow-up of 24 months. All of those patients had undergone the procedure of long-fusion (≥ 5 vertebras) with instrumentations by posterior-only approach.
General inclusion criteria for this study were as follows:

Age ≥ 45 years;

Those radiographic parameters met the criteria at least one of the followings: a, coronal curvature ≥ 20°; b, SVA ≥ 5 cm; c, PT ≥ 25°; d, TK ≥ 60° [16 (link), 17 (link)].

The research data before and after surgery, including demographics, surgical and radiographic parameters, were integrated.

The follow-up duration ≥ 24 months.

Those having 1) prior spinal surgeries, 2) history of spinal tumor, 3) history of spinal infection such as tuberculosis, 4) ankylosing spondylitis, 5) any hip disorders, or 6) the differences between two lower extremities ≥ 2 cm were excluded.
In this current study, proximal junctional failure (PJF) was defined as fractures or subluxations happening in the UIV and/or UIV + 1; pedicle screw loosening, dislodgment, or even pullout from the UIV [18 (link)]. Demographics (age, gender, and BMI) and surgical data involving UIV, lower instrumented vertebra (LIV), and fixed segments (FS) were reviewed and documented. Postoperatively, follow-up time and PJF-free survival time after surgery were documented. Radiographs at the pre-operation, the immediate post-operation, and the final follow-up were collected.