A comparison of feasibility and safety of percutaneous fluoroscopic guided thoracic pedicle screws between Europeans and Asians: is there any difference?

PURPOSE: To directly compare the safety of fluoroscopic guided percutaneous thoracic pedicle screw placement between Caucasians and Asians.

METHODS: This was a retrospective computerized tomography (CT) evaluation study of 880 fluoroscopic guided percutaneous pedicle screws. 440 screws were inserted in 73 European patients and 440 screws were inserted in 75 Asian patients. Screw perforations were classified into Grade 0: no violation; Grade 1: <2 mm perforation; Grade 2: 2-4 mm perforation; and Grade 3: >4 mm perforation. For anterior perforations, the pedicle perforations were classified into Grade 0: no violation, Grade 1: <4 mm perforation; Grade 2: 4-6 mm perforation; and Grade 3: >6 mm perforation.

RESULTS: The inter-rater reliability was adequate with a kappa value of 0.83. The mean age of the study group was 58.3 ± 15.6 years. The indications for surgery were tumor (70.3 %), infection (18.2 %), trauma (6.8 %), osteoporotic fracture (2.7 %) and degenerative diseases (2.0 %). The overall screw perforation rate was 9.7 %, in Europeans 9.1 % and in Asians 10.2 % (p > 0.05). Grade 1 perforation rate was 8.4 %, Grade 2 was 1.2 % and Grade 3 was 0.1 % with no difference in the grade of perforations between Europeans and Asians (p > 0.05). The perforation rate was the highest in T1 (33.3 %), followed by T6 (14.5 %) and T4 (14.0 %). Majority of perforations occurred medially (43.5 %), followed by laterally (25.9 %), and anteriorly (23.5 %). There was no statistical significant difference (p > 0.05) in the perforation rates between right-sided pedicle screws and left-sided pedicle screws (R: 10.0 %, L: 9.3 %).

CONCLUSIONS: There were no statistical significant differences in the overall perforation rates, grades of perforations, direction of perforations for implantation of percutaneous thoracic pedicle screws insertion using fluoroscopic guidance between Europeans and Asians. The safety profile for this technique was comparable to the current reported perforation rates for conventional open pedicle screw technique.