Preliminary Evaluation Of Minimally Invasive Posterior Lumbar Interbody Fusion (PLIF) Assisted By X-Tube System In The Treatment Of Low Back Disorders

Objective To evaluate the clinical outcomes of minimally invasive posterior lumbar interbody fusion (PLIF) assisted by X-Tube system for the management of degenerative lumbar disease.Methods A total of 31 patients, 17 male and 14 female with ages from 38 to 75 (average 54.2 yrs), underwent minimally invasive PLIF assisted by the X-Tube system from May 2005 to February 2006. The index diagnosis was lumbar spondylolisthesis in 14 cases, spinal stenosis in 8 cases, separation of the posterior ring apophysis in 5 cases, interveterbral space stenosis with disk herniation in 4 cases. Nonresponse or inadequate response to conservative management of total patients for 6 months. The operative duration and blood loss were evaluated. The changes of postoperative serum level of Creatinine Kinase was estimated as well, and compared with control group. The clinical functionaloutcomes were evaluated according to Oswestry disability questionnaire.Results Opera tive time was 140～225 min, and mean duration was 176 ± 22 min. Blood loss was 270～750 ml, mean loss was 406 ± 96 ml. The index of postoperative serum level of Creatinine Kinase was lower obviously in minimally invasive PLIF than the open. The position of 2 screws in 2 cases wasn't ideal, but nerve root wasn't disfunction. One case with spinal stenosis felt numb in domain dominated by lefe L₅ nerve root in postoperation, and symptom was disappeared within 2 weeks with conservative management. Total 31 patients were followed up. The time of follow-up was 7～17 months, the mean was 12.2 months. The preoperative back pain and sciatica was disappear. Functional outcomes were quantified using the Oswestry Disability Index. The average Oswestry scores decreased from (40.6 ±5.1) preoperatively to (17.4 ± 6.5) at postoperative first day and (9.5 ± 4.0) at final follow-up. The outcomes was good when the scores difference exceeded 15 according to the FDA's standard. 29 patients' scores changed over 15 (93.5%). The outcomes of operation was satisfied.Conclusion Minimally invasive PLIF assisted by X-Tube system minimize blood loss and tissue trauma, shorten the operative, recovery and bony union time, the short-term outcomes are excellent.