[Modified transforaminal lumbar interbody fusion for the treatment of lumbar degenerative disease].

OBJECTIVE: To analyze the clinical effects of modified transforaminal lumbar interbody fusion (TLIF) for the treatment of lumbar degenerative disease.

METHODS: From October 2003 to December 2006, 33 patients with lumbar degenerative disease (L3-S1) were treated by modified TLIF. There were 14 males and 19 females with an average age of 52.2 years (33 to 70 years). The median disease course was 1.8 years (4 months to 15 years). A total of 42 levels were fused, including 24 cases of single level and 9 cases of double levels. The results of preoperative diagnosis were lumbar degenerative spondylolisthesis with stenosis (8 cases), isthmic spondylolisthesis (5 cases), degenerative lumbar stenosis (16 cases), huge herniated disc with segmental instability (3 cases) and failed back surgery syndrome (1 case). During the modified TLIF procedure, total inferior facet process and inner half summit of superior facet process of TLIF side were resected to make the posterior wall of foramen opened partly. After the bone graft (3 to 5 mL) was placed into the interbody space, a single rectangle Cage was inserted obliquely from 30 degrees to 40 degrees toward the midline. Combined with pedicle screw instrumentation, TLIF was accomplished. Middle canal and opposite side nerve root decompression were performed simultaneously when necessary.

RESULTS: Intraoperative dura mater rupture, postoperative cerebral spinal fluid leakage, deep wound infection and transient nerve root stimulation occurred in 1 case respectively, and were all recovered after treatment. No patients had permanent neurologic deficit or aggravation. All patients were followed up for 20 to 58 months (mean 27.2 months). At the follow-up after 1 year postoperatively, all the operated segments achieved fusion standard and no broken screw or Cage dislocation occurred. All 13 cases of spondylolisthesis were reduced thoroughly and maintained satisfactorily. Nineteen patients remained slight chronic back pain. There was significant difference (P < 0.05) in JOA score between preoperation (14.9 +/- 5.1) and postoperation (25.9 +/- 3.0). The rate of clinical improvement was 80.5% (excellent in 24 cases, good in 7 cases, and fair in 2 cases).

CONCLUSION: The modified TLIF carries out the less invasive principles in opening operations, simplifies the manipulation and expands the indication of TLIF to some extent, and the clinical results for the treatment of lumbar degenerative disease is satisfactory.