ABSTRACT

In this study, we aimed to retrospectively evaluate the clinical and radiological findings and the mid to long-term results of aseptic pseudoarthrosis that emerged after posterior thoracolumbar segmental instrumentation surgery for spinal deformities and vertebral fractures, based on surgeries in the Department of Orthopedia and Traumatology, Istanbul Training and Research Hospital, from February 1999 to February 2010.

The 32 patients with spinal pseudoarthrosis that were included in this study were divided into two groups (Group-1 consisted of 11 vertebral fractures and Group-2 of 21 spinal deformities). The mean follow-up period was 36 months (range: 6–110 months). The records of our patients were reviewed retrospectively and the final follow-up results of the patients were taken into account in the data preparation process. The predisposing factors and radiological findings of pseudoarthrosis were assessed in light of the literature. The clinical results of the patients were measured using the Scoliosis Research Society-30 (SRS-30) questionnaire. Categorical data were provided by conducting analyses using Pearson's chi-square and Fisher's Exact Test to assess the relationship with pseudoarthrosis. Numerical values were analyzed with the Mann-Whitney U Test and Pearson-Spearman Correlation Test.

The most common complaint was pain at the pseudoarthrosis site (26 patients, 81.3%). Diabetes mellitus, smoking, osteoporosis and non-steroidal anti-inflammatory drug use were not risk factors for spinal pseudoarthrosis in our patients. Rod or implant failure was recorded as the most common radiological finding of pseudoarthrosis in both groups (Group-1: 10 patients, 90.0%; Group-2: 18 patients, 85.7%). Progression of the deformity was a specific finding for Group-2 patients (14 patients, 66.6%), and middle column damage was only seen for Group-1 patients (3 patients, 27.3%). The number of fused vertebrae, halo signs around the screws, and number of non-fused vertebrae at the fusion level were significantly correlated with pseudoarthrosis (p<0.001; r=0.725). Patients had similar SRS-30 scores at the final follow-up (Group-1 average: 3.30; Group-2 average: 3.39) (p=0.984).

The number of fused vertebrae correlates with pseudoarthrosis. In this study, co-morbidities were not found to be significantly correlated with pseudoarthrosis.