Posterior Polyethylene Tethers Reduce Occurrence of Proximal Junctional Kyphosis After Multilevel Spinal Instrumentation for Adult Spinal Deformity: A Retrospective Analysis.

BACKGROUND

Proximal junctional kyphosis (PJK) is a common postoperative complication after adult spinal deformity (ASD) surgery and may manifest with neurological decline, worsening spinal deformity, and spinal instability, which warrant reoperation. Rates of PJK may be as high as 69.4% after ASD surgery.

OBJECTIVE

To evaluate the efficacy of junctional tethers for PJK prophylaxis after multilevel instrumented surgery for ASD with minimum 2-yr follow-up.

METHODS

Single-center retrospective analysis of adult patients (age ≥18 yr) who underwent ASD surgery with index operations performed between November 2010 and June 2016 and achieved minimum 2-yr follow-up. Patients with ASD were subdivided into 3 treatment cohorts based on institutional protocol: no tether (NT), polyethylene tether-only (TO), and tether with crosslink (TC). PJK was defined as a proximal junctional angle (PJA) >10° and 10° greater than the corresponding preoperative measurement. Patient demographics, operative details, standard radiographic scoliosis measurements (including PJA and assessment of PJK), and complications were analyzed.

RESULTS

Of 184 patients, 146 (79.3%) achieved minimum 2-yr follow-up (mean = 45 mo; mean age = 67 yr; 67.8% women). PJK rates reported for the NT, TO, and TC cohorts were 60.7% (37/61), 35.7% (15/42), and 23.3% (10/43), respectively. PJK rates among TC patients were significantly lower than NT (P = .01601).

CONCLUSION

Junctional tethers with crosslink significantly reduced the incidence of PJK and revisions for PJK among ASD patients treated with long-segment posterior instrumented fusions who achieved minimum 2-yr follow-up.