Comparison of adjacent segment degeneration following one-level mini-open or conventional open posterior lumbar interbody fusion / 中华骨科杂志

ABSTRACT

Objective To compare the difference of adjacent segment degeneration (ASD) following one-level mini-open or conventional open posterior lumbar interbody fusion (PLIF).Methods From October 2005 to September 2008,108 patients underwent one-level instrumented PLIF using two different approaches mini-open approach in 56 patients including 32 males and 23 females,aged from 32 to 68 years (average,53.8 years) and conventional open approach in 52 patients including 24 males and 28 females,aged from 27 to 69 years (average,52.6 years).The follow-up rates of the mini-open and conventional open groups were 91.1％ and 88.5％,respectively.The visual analog scale (VAS),Oswestry disability index (ODI),multifidus muscle injury and ASD were evaluated.Results There were no significant differences in VAS and ODI scores between two groups preoperatively,but the two scores in the mini-open group were significantly lower than those in conventional open group after surgery.Compared with the conventional open approach,less decrease of cross sectional area and less severe fatty degeneration of the multifidus muscle were observed in mini-open group.There were 4 cases of radiographic ASD in the mini-open group including two symptomatic cases,and 11 cases in the conventional open group including 4 symptomatic cases among them 2 required surgical intervention.Both radiographic and symptomatic ASD were correlated with the decrease of cross sectional area and degree of fatty degeneration of the multifidus muscle,but only symptomatic ASD was associated with the clinical results.Conclusion Compared with the conventional open approach,the mini-open PLIF has many advantages,such as better clinical outcomes,lower incidence of multifidus muscle atrophy,and lower incidence of radiographic ASD.