[Logistic regression analysis on the outcome predictive factors of ruptured lumbar disc herniation]

To investigate the outcome predictive factors of ruptured lumbar disc herniation after conservative treatment.

From June 2009 to June 2016, 147 patients with ruptured lumbar intervertebral disc herniation were treated with conservative treatment in the orthopedics department of Suzhou Traditional Chinese Medicine Hospital for clinical efficacy and MRI follow-up. Multivariate Logistic regression analysis(Stepwise regression method)was used to analyze the relationship between the 11 categorical variables and absorptivity of protrusions: sex(X1), age(X2), course of disease(X3) , the rate of protrusion(X4), the Komori type(X5), the MSU type(X6), the Iwabuchi type(X7), the Pfirrmann grade(X8), the Modic change on adjacent vertebrae(X9), spinal canal morphology(X10), the Schizas types of cauda equina sedimentation sign(X11).

A total of 64 cases of prominent reabsorption among all cases followed-up (absorption rate>=30%), accounting for 43.5%. The reabsorption of protrusions is more likely to occur in patients with a duration of less than 1 year(P=0.006), MSU type 3 (P=0.001), Iwabuchi type 1 or 5 (P=0.000), the Schizas type of cauda equina sedimentation sign A or B(P=0.004). Regression equation Y=-10.363+1.916X3+1.446X4-1.445X5+2.070X6+4.679X7+1.125X9+1.023X10+2.223X11. Such factors as age, gender, Pfirrmann classification and spinal canal morphology had no significant effect on reabsorption of protrusions.

Ruptured lumbar disc herniation can be reabsorbed after nonoperative treatment. And the reabsorption of protrusions is more likely to occur in patients with a duration of less than 1 year, MSU type 3, Iwabuchi type 1 or 5, the Schizas type of cauda equina sedimentation sign A or B, which can be used as the key reference factors for predicting the outcome of the projections.