Surgical treatment for special type of lumbar disc herniation by transmultifidus approach and unilateral pedicle screws fixation

[Objective]To investigate the clinical outcomes of surgical treatment for single-level special type of lumbar disc herniation(STLDH) by traditional median approach and bilateral pedicle screw fixation(group A) versus transmultifidus approach and unilateral pedicle screw fixation(group B).[Methods]Seventy-one patients(41 in group A,39 in group B) with single-level STLDH were treated between March 2007 and March 2009 by pedicle screw fixation combined with transforaminal lumbar interbody fusion.The indexes of surgical trauma,systemic inflammatory response,clinical outcomes,fusion rate and paravertebral muscle injury were compared between two groups.[Results]The mean time of following-up was 2.8 years(range,2.2-4.1 years) in group A and 2.7 years(range,2.1-4.2 years) in group B.There were significant differences(P0.05) between the 2 groups regarding to intraoperative blood loss,postoperative drainage,length of incision,peak temperature within 3 days postoperatively,leucocytes and C reactive protein and creatine kinase MM at 24 hours postoperatively and C reactive protein at 6 days postoperatively in peripheral blood,showing superiorities in group B.At the last following-up,the ODI and VAS scores were significantly improved in both groups(P0.05).Group B showed better results regarding to ODI and back pain VAS scores(P0.05),but not significantly(P0.05) to leg pain VAS scores in both groups.Strong fusion rates were 92.7% in group A and 93.8% in group B,showing no difference(P0.05).The average atrophy ratio was(37±13)% versus(15±7)% in group A and B respectively,with statistically significant differences(P0.05).[Conclusion]Both surgical treatments are effective for single-level STLDH.Compared with traditional median approach and bilateral pedicle screw fixation,transmultifidus approach and unilateral pedicle screw fixation has advantages of minimal surgical trauma,slighter postoperative systematic inflammatory response,less paravertebral muscle injury and lighter postoperative back pain.