Table 2

Precision of O-arm assisted spinal navigation.

LevelNo. of screwsAxialSagittal
Mean virtual angle (°)Mean actual angle (°)Mean angle difference (°)Axial Percent errorMean virtual angle (°)Mean actual angle (°)Mean angle difference (°)Sagittal Percent error
T1922.421.22.561.25%4.561.783.001.59%
T21117.817.32.731.38%4.004.452.821.52%
T31115.514.83.271.66%2.452.182.091.14%
T4818.115.83.131.57%4.382.632.001.08%
T51516.115.12.531.30%3.472.471.931.04%
T61213.812.12.001.03%3.253.251.000.55%
T71212.812.32.001.04%4.173.331.830.99%
T81413.913.51.710.88%4.004.791.790.97%
T91513.113.31.400.73%3.204.201.670.91%
T101311.110.11.770.93%1.690.771.690.92%
T11169.99.41.941.02%5.695.381.690.91%
T12108.79.01.300.69%2.442.331.440.75%
L11115.114.41.640.84%3.914.181.911.03%
L21420.719.12.571.25%3.713.642.501.35%
L31218.818.72.001.00%4.583.671.750.95%
L41816.916.82.671.33%3.864.142.191.22%
L52214.614.82.551.29%3.054.322.451.34%
S11711.210.71.590.83%3.943.244.352.32%
Total24014.814.22.171.113.673.492.161.17%
P value 0.0016P value = 0.19