It is a retrospective comparative cohort study. In PJK revision patients, the objective was to determine the incidence, risk factors, and outcomes of recurrent proximal junctional kyphosis (r-PJK). After primary surgery, several studies have established the incidence and risk factors for PJK. However, only a few studies have looked at PJK recurrence after PJK revision. A multicenter database of patients who had PJK revision surgery and were followed for at least two years was studied. Those with r-PJK and patients without recurrence no-Proximal Junctional Kyphosis were compared on demographic, surgical, and radiological outcomes (n-PJK). The Oswestry Disability Index, Short Form-36, and Postoperative Scoliosis Research Society-22r were compared. The preoperative spinopelvic, cervical, and cervicothoracic radiographic values were compared to the most recent spinopelvic, cervical, and cervicothoracic radiographic parameters. To find r-PJK risk factors, researchers utilized both univariate and multivariate analyses. The researcher’s logistic regression technique was used to create a prediction model. With an average follow-up of 21.8 months, 70 patients matched the inclusion criteria. The average age of the patients was 66.3 ± 9.4 years, and 80% of them were female. Patients had a -31.7°± 15.9° proximal junctional angle before revision. Recurrent PJK was found to be 44.3% of the time. Pre-revision thoracic pelvic angle (OR:1.060 95% CI 1.002; 1.121; P=0.042) and pre-revision C2-T3 sagittal vertical axis (SVA; OR:1.040 95% CI [1.007; 1.073] P=0.016) were both found to be independent predictors of r-PJK using logistic regression. With these parameters, classification accuracy was 72.7%, precision was 80.6%, and recall was 73.5%. The researchers discovered that change in SVA (OR: 0.981 95% CI [0.968; 0.994] P=0.005) was the only predictor of r-PJK with an accuracy of 66.7%, precision of 74.2%, and recall of 69.7% when analyzing correction, or change in alignment, following revision surgery. Patients who underwent PJK revision surgery had a 44% recurrence rate. Pre Revision thoracic pelvic angle and pre-revision C2-T3 SVA were found to be independent predictors of r-PJK using logistic regression based on pre-revision factors.

 

Link:journals.lww.com/spinejournal/Abstract/2020/01010/Recurrent_Proximal_Junctional_Kyphosis__Incidence,.10.aspx

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