Fusion Assessment in Stand Alone Oblique lumbar interbody fusion in Adult Degenerative Lumbar Scoliosis: A Prospective Study

Background data: The degenerative lumbar diseases form a burden on both the patients and the society. The development of the degenerative process is highly linked to the aging process as discussed by Kirkandly Willis where the degenerative spine passes through 3 phases of process that results in the degenerative diseases. The management of the degenerative spine deformities varies and depends on various factors. Traditional surgical management involves instrumentation, decompression and fusion processes. Oblique Lumbar interbody fusion ‘OLIF’ is a novel technique when used alone as in stand-alone OLIF ‘SA-OLIF’ it could achieve degenerative deformity correction along with neural decompression, however, the final aim of SA OLIF where solid fusion is required still is under evaluation and literature lacks the essential data for this approach. This study aims to assess the fusion of the SA-OLIF in the management of degenerative lumbar scoliosis. Study Design: A Prospective clinical case study. Objective: To assess the fusion rates in patients suffering from degenerative lumbar scoliosis ADS after SA-OLIF. Patients and Methods: Patients with ADS following a specific inclusion criterion underwent SA OLIF. Pre-, and Post-operative clinical data; back and leg pain ‘VAS score’ and ODI, radiological data; for fusion assessment. Intra-operative data: operative time, amount of blood loss, complications ‘intra-operative or post-operative’ and hospital stay were all analyzed and compared statistically. Results: A total of 28 patients and 30 levels were operated by SA OLIF, with mean age 50.54±6.05 included 14 males and 14 females. The mean operative time/min, blood loss/ml and hospital stay/day was 91.29±14.23, 195.54±42.299 and 2.78±0.875 respectively. The mean of Back Pain ‘VAS’, The mean of Leg Pain ’VAS’ and ODI changed from pre-operatively 7.36±0.98, 6.36±0.911and 68.615±8.72 to 4.07±1.01, 2.07±0.9 and 20.23±4.7 in 1-year respectively. In this study we had 92.9% fusion rates after 1-year. Operative complications occurred in 3 cases with segmental artery injury. Post-operative complications were 1 cage dislodgment immediately post-operative and 2 cases of cage subsidence after 1-year. Conclusion: SA OLIF can result in high rates of fusion. There are multiple factors that determine the rate of fusion such as the quality of the vertebrae and endplate preservation during the preparation procedure.