Application Of Oblique Lateral Interbody Fusion In Lumbar Degenerative Diseases And Design Of The New Interbody Fusion Cage For OLIF Approach

ObjectiveTo evaluate the effect and security of treatment of lumbar degenerative diseases via oblique lateral interbody fusion and design an intervertebral fusion cage for OLIF.Methods1.A retrospective of 32 cases(male 13 cases,female 19 cases)with lumbar degenerative diseases from December 2016 to March 2018 who were treated by oblique lateral interbody fusion,whose mean age was 58.2±12.4 years(range 45-71 years).The index diagnosis was discogenic back pain in 7 cases,lumbar spinal stenosis in 18 cases,spondylolisthesis in 7 cases,and adjacent vertebral disease in 3 cases.Clinical outcomes were evaluated by Visual analogue scale(VAS),Oswestry disability index(ODI),and radiographic measurements.2.The shape and size of fusion cage were designed according to the Chinese lumbar anatomical measurement data.Then we made the fusion cage model by CAD drawing and 3D printing,the model was studied and tested repeatedly until the design was finalized.Results1.The operation of single level OLIF lasted for 23-40 min,with a mean duration of(28±9)min.Blood loss of single level OLIF was 10-55 ml,with a mean of(25±18)ml.The VAS score decreased from(8.4±2.7)preoperatively to(1.5±0.6)in 6 months after surgery,ODI score decreased from(65.8±18.4)preoperatively to(11.3±2.9)in 6 months after surgery.The height and area of intervertebral foramen,height of intervertebral space,diameter and area of vertebral canal after surgery were significantly improved compared with those before surgery.I grade fusion in 30 cases,II grade fusion in 2 cases.The ipsilateral hip flexor weakness in 1,contralateral numbness of the thigh in 1,these were released in 1 week.Peritoneal injury in lcase,subsidence in 3 cases.2.A new lumbar interbody fusion cage was designed successfully which can be used in OLIF surgery.The cage was in line with the Chinese lumbar anatomy and composed of PEEK fusion cage,titanium alloy and screws.Conclusion1.Oblique lateral interbody fusion can be used in lumbar degenerative diseases.There are several advantages associated with OLIF surgery such as short operation time,less trauma,less bleeding,etc.follow-up showed good short-term efficacy,and good safety.The follow-up results showed good short-term efficacy and good safety.2.Preoperative and postoperative imaging indexes of oblique lateral interbody fusion showed good indirect decompression effect and high rate of bone graft fusion.3.A new cage of OLIF was designed successfully which can be placed as a whole and is low notch,but its clinical efficacy and safety still need to be further studied and verified.