Objective　To study the characteristics of allogeneic fibula ring fusion cage (AFRFC) used in lumbar vertebral fusion and to compare the clinical outcome of transforlamina lumbar interbody fusion (TLIF) using AFRFC and metacarbon fiber rectangle fusion cage (MFRFC).　Methods　Ninety-one patients with lumbar vertebra retrogression

lumbar intervertebral disc protrusion

palindromia

lumbar spinal stenosis

lumbar vertebra slippage and unsteadiness

and lumbar discogenic pain

who were treated with transforlamina lumbar interbody fusion at Department of Orthopedics

Southwest Hospital

Third Military Medical University (Chongqing

China) from February 2005 to February 2007

were retrospectively analyzed. Of these patients

45 were treated with 3 AFRFC implanted into the vertebra to form a triangle

46 were treated with MFRFC with one MFRFC obliquely implanted into the vertebra. The patients were followed up for 3

6

12

and 24 months after operation

during which lumbar vertebra CR or CT film was checked to measure the height of confusion segment in inter-vertebral space

the offset and angulation of the sagittal centrum

and the back pain JOA was scored. Other indicators

such as nerve root injury

meninx membranous sac damage

or nerve root tension injury

were quantitatively evaluated and control study was undertaken.　Results　The follow-up time was 2-4 years. The average follow-up time was 35 months for the patients treated with AFRFC and 36.8 months for the patients treated with MFRFC. The rate of tension injury at nerve root was 0% for the patients treated with AFRFC and 8.7% for the patients treated with MFRFC (Chi square=2.29，P0.05). No nerve root injury and meninx membranous sac damage occurred in all patients during operation. The fusion rate was 97.8% for the patients treated with AFRFC and 93.5 % for the patients treated with MFRFC three months after operation (Chi square=0.24

P 0.05). The sedimentation rate in inter-vertebral space was 0% for the patients treated with AFRFC and 4.3% for the patients treated with MFRFC three months after operation (P0.05). The low back function recovery rate was 62.6of for the patients treated with AFRFC and 67.4% for the patients treated with MFRFC three months after the operation (P 0.05).　Conclusion　AFRFC is an ideal inter-vertebral fusion cage

which can effectively reduce the incidence of nerve root tension injury and restore the inter-vertebral space height.