Objective To analyze effective methods of surgery for isthmic lumbar spondylolisthesis of grade Ⅱ or above. Methods From January 2006 to June 2011, 42 patients with a mean age of 51 years (range, 24 to70 years) with isthmic lumbar spondylolisthesis of grade Ⅱ or above treated with pedicle screw fixation and interbody fusion, including 13 males and 29 females, were reviewed retrospectively. Isthmic defects were located at L4 in 15 cases, at L5 in 27 cases.28 cases were in grade Ⅱ spondylolisthesis and 14 cases in Ⅲ. The clinical outcome were evaluated according to Oswestry disability index(ODI) and the change of radiographic data. Results All cases had got complete follow-up for 12~48 months (average 28.5 months). In one case, the internal instrument was adjusted because of nerve root injury caused by screw malposition. There was no complication such as incision infection and instrument failure. Post-operatively, the slipping degree was reduced, the height of intervertebral space increased and slipping angle decreased. The radiographic data had no obvious loss in the final follow-ups. Bony fusion was solid in 40 cases, but poor in 2 cases. The objective clinical outcomes of the ODI were in average 33.6±6.5 before operation and 10.8±4.1 after operation. Conclusion There are characteristics in isthmic lumbar spondylolisthesis of grade Ⅱ or above, such as long time medical history, severe patient's conditions and obvious pathological change. It is recommended that Mono-segment fixation, sufficient relaxation, maximal restoration, and interbody cage insertion be adopted for treatment of isthmic lumbar spondylolisthesis of grade Ⅱ or above , which canachieve rigid fixation and fusion.
Just Accepted