Design A New Kind Of Surgical Instrument To Trapezoid Osteotomy On The Adult Anterior Cervical Vertebra

Objective: This study was aimed to design a new kind of surgical instrument for trapezoid osteotomy of the anterior cervical decompression and orthotope bone graft.Method: We selected 80 CT pictures of the Cervical Spondylotic Myelopathy and/or Cervical Spondylotic Radiculopathy adult patients, measured the transverse diameter(a), sagittal diameter(b), height(c) of the vertebra and the height of the intervertebral space(d) on all the affection cervical vertebral segments, and then, designed and produced the trapezoid-osteotomy-instrument based on the imageology measurement. We selected 8 complete wet adult neck specimens, and divided them into two groups randomly.In group I, ordinary bone knife was used to carry out the trapezoid osteotomy on C3-C4 and C5-C6, or C4-C5 and C6-C7 segments separately. In group II, the trapezoid-osteotomy-instrument was used to carry out the trapezoid osteotomy on C3-C4 and C5-C6, or C4-C5 and C6-C7 segments separately. Finally, we compared the time of trapezoid osteotomy operation, the shape of the trapezoid bone-block cutted , the depth and the angle of the trapezoid osteotomy between the two groups.Results: Based on the imageology measurement, We designed and produced the trapezoid-osteotomy-instrument with large, medium and small 3 kinds. We carried out trapezoid osteotomy operation on the complete wet adult neck specimens :In group I ,we used ordinary bone knife to carry out the trapezoid osteotomy on C3-C4 and C5-C6, or C4-C5 and C6-C7 segments twice separately, the time of operation were 3.0 min～7.3min, averaging 5.4 min. We got 8 trapezoidal bone bloces, in them, 3 were integral and with standard shape , osteotomy depth and angle, 1 was incompleted , 1 was cut too shallow, 1 was cut too deep, 2 were with' large angle and irregular shape. In group II,we used the trapezoid-osteotomy-instrument to carry out the trapezoid osteotomy on C3-C4 and C5-C6, or C4-C5 and C6-C7 segments twice separately, the time of operation were 1.5 min～4.0min, averaging 2.6 min. We got 8 trapezoidal bone bloces, in them, 7 were integral and with standard shape ,osteotomy depth and angle. 1 was cut too shallow ,non of them incompleted.Conclusions: The operation of trapezoid osteotomy carried out with trapezoid-osteotomy-instrument is simple, convenience, accuracy, security, and with short operation time and high success rate. It will become a new and usefull instrument for the adult anterior cervical decompression and orthotope bone graft .