Pedikelschraubenlockerung bei Verwendung von Carbon-Fiber-verstärkten PEEK-Schrauben nach dorsaler Stabilisierung bei Spondylodiszitis

Screw loosening and halo formation around the screws in carbon fibre reinforced PEEK implants is under debate. This study aims to assess the frequency of pedicle screw loosening and safety in the use of Carbon/PEEK implants for treating pyogenic spondylodiscitis across spinal segments in the cases of one hospital.

A retrospective analysis from 2017 to 2023 involved 142 patients after posterior fusion with using Carbon/PEEK implants, including a comprehensive review of medical records, MRI, and CT scans. Statistical analysis used descriptive statistics and Chi-square, with significance set at p < 0.05.

The study group consisted of 92 males (65%) and 50 females (35%), with an average age of 69.54 years (±12.5). Surgeries were conducted at a single level in 108 patients (76%), at two levels in 14 patients (10%), and at 3 to 5 levels in 20 patients (14%). Posterior fusion procedures were conducted across various spinal segments: cervicothoracic junction in 1 patient (0.7%), thoracic spine in 29 patients (20.4%), thoracolumbar junction in 7 patients (4.9%), and lumbar spine in 105 patients (73.9%). Screw loosening was observed in 16 patients (11.3%): in the thoracic spine for 4 patients (2.8%), at the thoracolumbar junction for 3 patients (2.1%), and in the lumbar spine for 9 patients (6.3%). These differences were statistically significant (Chi-Square = 8.06; p = 0.045). Repeat surgical procedures due to screw loosening were performed in only 1 case (0,7%).

Screw loosening was observed in 16 patients (11,3%), and repeat surgical intervention was only necessary in a single patient. Thus, examining a six-year treatment history of spondylodiscitis patients using Carbon/PEEK implants suggests their sufficient safety. No increased risk of screw loosening was observed. However further studies including more patients are required before final conclusions can be drawn.