[Effect evaluation of over 5 year follow up of unilateral pedicle screw fixation with transforaminal lumbar interbody fusion for lumbar degenerative diseases].

OBJECTIVE:To evaluate the clinical effects of over 5 year follow up of unilateral pedicle screw fixation with transforaminal lumbar interbody fusion(TLIF) in treating lumbar degenerative diseases. METHODS:The clinical data of 24 patients with lumbar degenerative disease underwent unilateral pedicle screw fixation with transforaminal lumbar interbody fusion from March 2007 to October 2009, were retrospectively analyzed. There were 13 males and 11 females, aged from 34 to 68 years old with an average of 52 years. Postoperative pain and functional results were analyzed by the visual analogue scale(VAS) and Oswestry Disability Index(ODI). Radiological examination was obtained for each patient to assess the height of intervertebral space, postoperative intervertebral fusion conditions and general complications. RESULTS:All patients were followed up from 5 to 8 years with an average of 6.7 years. VAS scores of low back pain and leg pain decreased from preoperative 7.82±0.71, 8.42±1.24 to postoperative 1.87±0.81, 2.23±1.62, respectively(P<0.05). ODI decreased from preoperative(53.42±8.26)% to postoperative(12.45±7.67)%(P<0.05). Postoperative intervertebral space height in different segments were improved than preoperative(P<0.05), but in final follow up it was decreased than 3 months after operation(P<0.05). There was no significant difference in the postoperative intervertebral space height between the operated side and non operated side. But at final follow up, the intervertebral space height of non operated side was obviously loss. At final follow up, the fusion rate was 95.8%. The incidence of adjacent segment degeneration was 45.8%. The paraspinal muscle fibrosis incidence was 8.3%. No complications such as secondary scoliosis, intervertebral height loss, cage slippage, screw loosening and internal fixation breakage were found. CONCLUSIONS:Unilateral pedicle screw fixation with TLIF is a satisfactory method and can obtain good effects in treating lumbar degenerative diseases according to over 5 year follow up, however, its indications should be well considered. But the problems such as intervertebral space height of operated side loss and adjacent segment degeneration after unilateral pedicle screw fixation need further clinical study.