Techniques and accuracy of thoracolumbar pedicle screw placement

Table 3 Summary of studies that have evaluated free-hand pedicle screw placement

	Most common pathology	Screw location	Number of patients	Number of screws	Accuracy (%)	Revision rate (%)
Gertzbein et al[5], 1990	Trauma	T8-S1	40	167	71.9	N/A
Liljenqvist et al[9], 1997	Scoliosis	T4-T12	32	120	75.0	N/A
Kim et al[23], 2004	Scoliosis	T1-T12	Unclear	577	93.8	0
Karapinar et al[31], 2007	Trauma	T10-L3	98	640	94.2	0
Schizas et al[32], 2007	Trauma	T1-T6	13	60	88.3	0
Kotil et al[33], 200	Trauma	T1-L5	Unclear	368	93.5	1.5
Modi et al[26], 2009	Scoliosis	T1-T12	43	854	93.0	N/A
Parker et al[27], 2011	Degenerative/Deformity	T1-S1	964	6816	98.3	0.8

N/A: Not applicable.