膝关节骨关节炎的屈伸膝肌存在脊髓水平的选择性抑制

目的 了解膝关节骨关节炎屈伸膝肌抑制的特性。方法 对36例单侧膝骨关节炎患者进行股神经和坐骨神经的最大电刺激、定量的髌腱反射和股二头股健反射诱发曜闰的肌电图检查，比较健患侧的差异。结果 36例单侧膝骨关节炎健患侧的股神经最大电刺激的诱发电位峰－峰值和潜伏期无显著差别，但患侧的髌腱反射诱发电位峰－峰值要显著低于健侧（P＜0.001）。健患侧坐骨神经最大电刺激的诱发电位的潜伏期、峰－峰值和股二头肌腱反射诱发电位峰－峰值判别没有显著性意义（P＞0.05）。结论 从脊髓水平的反射角度看，膝骨关节炎的伸膝肌存在抑制而屈膝肌无明显抑制，膝骨关节炎对屈伸膝肌运动神经元的抑制有选择性。

Existence of selective inhibition of spinal level in the extersors and flexors of osteoarthritic knee

Objective To study the speciality of extensors and flexors on knee osteoarthritic patients. Methods Maximal electrical twitch of femoral nerve and ischiatic nerve, electromyographically tested quantitative patella tendon reflex and biceps femoris tendon reflex were done on 36 unilateral knee osteoarthritic patients. The differences of electrophysiological parameters between the involved and uninvolved limbs were compared. Results There were no statistical differences of peak peak values and latencies at maximally stimulating the femoral nerve between the involved and uninvolved limbs, but the peak peak values of patellar reflex at involved sides were statistically lower than those of uninvolved sides. There were no statistic differences of peak peak values and latencies at maximally stimulating the ischiatic nerve, and of biceps femoris tendon reflex between involved and uninvolved limbs. Conclusion Viewing at the point of spinal level reflexes,inhibition exists the extensors but not the flexors of knee osteoarthritis. There exists a selective inhibition between knee extensors and flexors motoneurons.