The influence of intramedullary hyperintensity on T2-weighted MRI on the outcome of cervical arthroplasty for cervical spondylotic myelopathy / 中华骨科杂志

ABSTRACT

Objective To investigate whether the hyperintensity on T2?weighted MRI affects the outcome of cervical ar?throplasty (CA) for cervical spondylotic myelopathy (CSM). Methods 69 patients with CSM who had undergone CA between June 2005 and December 2007 were retrospectively reviewed. They were divided into three groups according to the intensity of T2?weighted imagesGroup A, whose intensity of T2?weighted images in spinal cord compression spot was equisignal;Group B, hyper?intensity with obscure border; Group C, hyperintensity with clear border. There were 22 males and 19 females in group A aged from 27 to 63 years old, whose duration of disease was between 3 to 72 months, and there were 34 single?segment cases, 5 double?segment and 2 triple?segment cases. There were 9 males and 9 females in group B aged from 30 to 61 years old whose duration of disease was between 3 to 24 months, and there were 12 single?segment and 6 double?segment cases. There were 4 males and 6 fe?males in group C aged from 28 to 56 years old whose duration of disease was between 1 to 24 months, and there were 8 single?seg?ment and 2 double?segment cases. Two types of artificial cervical disc were usedBryan Disc in 42 cases and Prodisc?C in 44 cas?es. The duration of Group A (24.7 ± 27.9 months) was significantly longer than that in Group B (6.6 ± 7.4 months) and Group C (11.1±9.5 months). The follow?up period was from 48 to 86 months with an average time of 61 months. The preoperative X?ray and MR as well as postoperative X?ray were collected. The history, compress ratio of MRI, the ROM of cervical segments pre and post?operatively were recorded and Japanese Orthopaedic Association (JOA) was used to evaluate the neurological function. Results Preoperative compress ratio of MRI were 43.3%± 15.2%, 42.4%± 10.7%and 41.9%± 14.8%respectively;preoperative segmental ROM were 9.6°±2.5°, 9.0°±1.7° and 9.1°±1.9° respectively. Preoperative JOA score were 13.6±1.2, 13.1±1.3 and 12.9±1.8, re?spectively. Postoperative JOA score at the latest follow?up were 16.2±1.0, 15.8±1.2 and 15.7±1.6 respectively. There was no statis?tic difference among these groups. Preoperative increased signal intensify on T2?weighted MRI in patients with cervical spondylot?ic myelopathy may not affect the outcome of cervical arthroplasty.