Standardized translaminar spinal tethering to prevent proximal junctional kyphosis in adult spinal deformity correction surgery.

Abstract

PURPOSE: This study evaluated whether standardized proximal translaminar spinal tethering at the upper instrumented vertebra (UIV) + 1 and UIV + 2 reduces the incidence of proximal junctional kyphosis (PJK) and the need for revision surgery in patients undergoing thoraco-lumbar deformity correction for adult spinal deformity (ASD). METHODS: A retrospective cohort study was conducted on 59 adult patients who underwent thoraco-lumbar deformity correction surgery between October 2019 and August 2023. Patients were categorized into tethered (T) and non-tethered (NT) groups. Radiographic measurements were performed preoperatively, early postoperatively (≤ 3 months), and late postoperatively (> 3 months) to assess PJK, defined as a proximal junctional angle (PJA) ≥ 10° and ≥ 10° greater than the corresponding preoperative measurement. RESULTS: Overall, 18 patients (30.5%) developed PJK, with no significant difference between tethered (12%) and non-tethered (20.5%) patients within the first 3 months (p = 0.384). However, at late follow-up, the PJK rate was significantly higher in non-tethered (41.1%) compared to tethered (16%) patients (p = 0.037), with non-tethered patients being 3.67 times more likely to develop PJK (95% CI = 1.03–13.07). Kaplan–Meier analysis showed a significant reduction in time-dependent PJK development for tethered patients (p = 0.027). Revision surgery was required in 11.8% of non-tethered patients compared to 4% of tethered patients (p = 0.289). CONCLUSION: Proximal translaminar tethering at UIV + 1 and UIV + 2 effectively reduces the incidence of PJK in patients undergoing thoraco-lumbar deformity correction. However, the effect on surgical revision rates due to PJK remains unclear, warranting further long-term prospective studies.