Comparison of Scheuermann's Kyphosis Correction by Posterior Only Thoracic Pedicle Screw Fixation vs. Combined Anterior/Posterior Fusion

Purpose: To compare the results of posterior only treatment with segmental thoracic pedicle screw constructs (TPS) versus combined anterior/posterior fusion in patients with Scheuermann's kyphosis.

Methods: 18 patients who underwent posterior only fusion (PO) and 21 patients who underwent anterior and posterior fusion (AP) for treatment of Scheuermann's kyphosis were followed for a minimum of 2 years. The two groups were well matched according to average age (PO-17.3, AP-18.0, p=0.60), maximum preoperative kyphosis (PO-84.4º, AP-89.1º, p=0.21), flexibility index (PO-0.407, AP-0.408, p>0.99), and posterior fusion levels (PO-12.2, AP-12.1, p=0.95). 12/18 (67%) patients in the PO group versus 0/21 of the AP group had apical Smith-Petersen osteotomies. Posterior fixation in the PO group was performed using segmental TPS constructs. Fixation in the AP group was achieved with hybrid hook/screw constructs. Both groups had posterior iliac bone autografting. Patient radiographs were evaluated preoperatively, postoperatively, and at final follow up. At final follow up, SRS-30 questionnaire data, and complications were recorded.

Results: The mean residual kyphosis of the PO group averaged 38.2º postoperatively, and 40.4º at final follow up. This was statististically better than the AP group (51.9º and 54.4º, p<0 .001 and p="0.14)." respectively). Even without an anterior release, kyphosis correction in the PO group averaged 54.2% postoperatively 51.8% at final follow up. This was significantly better than AP (41.2% 38.5%, p<0.001 SRS-30 outcome scores up were comparable between 2 groups (PO-120.4, AP-128.0, The had 8/21 (38%) patients with complications including paraplegia (1), proximal junctional hook pull out infection (2). no (p="0.003)."

Conclusion: Posterior only treatment with TPS for Scheuermann's kyphosis achieved and maintained better kyphosis correction than with circumferential fusion with significantly less complications.