腰椎后路融合术后腰痛患者椎旁肌电生理的研究

目的：研究腰椎后路融合术后腰痛患者多裂肌自发电位数量情况及其发生腰痛的原因。方法将我院收治的86例腰椎后路融合术后患者按疼痛程度分为腰痛组46例和对照组40例，采用针极肌电图测量其多裂肌中自发电位数量、位置，并比较两组患者在自发电位数量方面的差异，以及自发电位分布和手术区域、内固定区域、椎板开窗的关系。结果（1）腰痛组多裂肌中的异常自发电位分数（12.87±2.34）分明显大于对照组（2.28±2.84）分（ P＜0.01）；（2）所有自发电位均位于手术区域内，手术区域以外的多裂肌中未见自发电位分布；（3）腰痛组内固定区域内多裂肌自发电位分数（8.76±1.95）分显著高于内固定区域外（4.11±1.39）分（ P＜0.01）；（4）开窗侧自发电位分数（2.38±0.70）分和未开窗侧（2.50±0.56）分接近，差异无统计学意义（P＞0.05）。结论（1）腰椎后路融合术后多裂肌中的自发电位，主要是由于手术本身所致。（2）腰椎后路融合术后腰痛患者脊神经背内侧支损伤程度较重，这可能是导致术后腰痛的原因。

A study of electrophysiological changes of the lumbar paraspinal muscle after posterior lumbar interbody fusion

Objective To investigate the differences in the spontaneous potential activity in the multiifdus muscle both in the patients with low back pain after posterior lumbar interbody fusion （ PLIF ） and in the control group.Methods A total of 86 patients who underwent PLIF were divided into the low back pain group and the control group depending on the pain degree. The activity and location of spontaneous potentials in the multifidus muscle were measured by the electromyogrphy （ EMG ）. The differences in the spontaneous potential activity were compared between the 2 groups, and the relationship between the distribution of spontaneous potentials and the operative region, internal ifxation area and fenestration discectomy were explored.Results In the low back pain group, the score of abnormal spontaneous activity in the multiifdus muscle was （ 12.87±2.34 ） points, which was obviously larger than （ 2.28±2.84 ） points in the control group （P〈0.01 ）. All the spontaneous potentials were located in the operative region, and no others were noticed outside. In the low back pain group, the score of spontaneous activity in the multiifdus muscle was （ 8.76±1.95 ） points in the internal ifxation area, which was obviously larger than （ 4.11±1.39 ） points outside （P〈0.01 ）. The spontaneous potential activity in the laminectomy side （ 2.38±0.70 ） did not present signiifcant differences （P=0.45 ） when compared with that in the contralateral side （ 2.50±0.56 ）.Conclusions The spontaneous potential activity in the multiifdus muscle after PLIF is resulted from the operation itself. The score of spontaneous activity in the multiifdus muscle in the low back pain group is signiifcantly larger than that in the control group. It is pointed out that injury of the lumbar medial branch is much severer, which may cause low back pain after the operation.