Ai-Min Wu, Wen-Fei Ni, Zhen-Xuan Shao, Xiang-Jie Kong, Nai-Feng Tian, Yi-Xing Huang, Zhong-Ke Lin, Hua-Zi Xu, Yong-Long Chi


April 2015, Volume 24, Issue 4, pp 852 - 858 Ideas and Technical Innovations Read Full Article 10.1007/s00586-014-3663-6

First Online: 13 November 2014

Purpose

To design and investigate a novel technique of percutaneous posterior transdiscal oblique screw fixation with lateral interbody fusion.

Methods

CT scans of 45 patients were collected and imported into Mimics software for three-dimensional (3D) reconstruction. Cylinders were drawn to simulate the trajectory of the oblique screw. Six measurements were obtained for each unit to design a right size cage: a the distance between the intersection of the simulated trajectory of the screw with the inferior border of the upper vertebra and its anteroinferior corner; b the distance between the intersection of the simulated trajectory of the screw with the superior border of the inferior vertebra and its anterosuperior corner; h the height of the intervertebral space; θ the angle between simulated trajectory of screw and the upper endplate of inferior vertebra; uw: the width of the inferior endplate of upper vertebra; iw: the width of upper endplate of inferior vertebra. Three intact adult fresh-frozen cadaveric specimens were obtained, percutaneous posterior transdiscal oblique screw fixation was performed under X-ray apparatus, and interbody cage was implanted by assistance with special self-retaining retractor system and endoscope.

Results

According to the results of data measured from 3D images, trapezoid shape interbody cages with suitable size were designed. Percutaneous posterior oblique screw fixation with lateral interbody fusion was performed on three cadaveric specimens successfully.

Conclusion

Using specially designed trapezoid shape interbody cages, assisted by intra-operative image intensification and endoscope, it is feasible to perform percutaneous posterior transdiscal oblique screw fixation with lateral interbody fusion technique.


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