Design and verification of percutaneously puncturing apparatus for the vertebrae

Daochen LIANG; Huilin YANG; Weiming LIAO; Qing LI; Kang LIU; Hongtao ZHANG

ABSTRACT

BACKGROUND:

Vertebroplasty or kyphoplasty is monitored under imaging apparatus. Standard entopic phase and standard lateral phase were obtained via repeatedly adjusting C-arm preoperatively. Puncturing angle was adjusted in experience, and time and X-ray exposure were significantly increased.

OBJECTIVE:

To design percutaneously puncturing apparatus for vertebrae in order to reduce X-ray exposure and shorten the operating time. DESIGN, TIME AND

SETTING:

A designing and verifying study was performed at the Department of Orthopaedics, the First Hospital Affiliated to Soochow University between October 2004 and March 2005. MATERIALS Five samples of thoracic waist and lumbar vertebrae with soft tissues did not have abnormalities or defect.

METHODS:

CT scan and standard lateral image of 5 vertebrae specimen from T11 to L5 were got. Every "e" angle and "f" angle were measured and puncturing approaches were analyzed for kyphoplasty in thoracic and lumbar vertebrae. Percutaneously guiding instrument was only used on the left sides. The effect was analyzed and the exposure times were compared between the left and the right sides. MAIN OUTCOME

MEASURES:

Determination of puncturing approach, and X-ray exposure times between the left and the right sides.

RESULTS:

The entry point was at the superior-lateral 1/4 quadrant of the cross by a line passed the mid-point of two transverse process roots and a line passed the back edge of the superior articular process. In standard anterior posterior image, the entry points were at 2 o'clock on the left pedicle shadow and 10 o'clock on the right pedicle shadow respectively. The exposure times were 12.61±1.69 on the left and 23.19±1.60 on the right (P < 0.05).

CONCLUSION:

Ideal position can be arrived in puncturing according to the exact position, correct entry point and puncturing according to te exact position,correct entry point and puncturing angles.Application of percutaneously guiding instrument can sgnificantly diminish exposure time.