Intraobserver and interobserver reproducibility of Fujiwara rating of interspinous ligament by magnetic resonance imaging and relationship between lumbar disc degeneration and interspinous ligament degeneration

OBJECTIVE: to assess the clinical applicability of Fujiwara rating by intraobserver and interobserver analysis and to compare it to Pfirrmann rating of disc degeneration. METHODS: eighty-seven interspinous ligaments and lumbar intervertebral discs of 29 patients (13 males and 16 females) with mean age of 49 years (24 to 81 years) were evaluated by magnetic resonance imaging by Fujiwara and Pfirrmann rating system. The assessment of Fujiwara rating was done by three observers in two occasions, with a minimal interval of 15 days. The assessment of Pfirrmann rating was done by three observers at the same time. Statistical analyses were done by Kappa index to compare the intraobserver and interobserver variation. RESULTS: the intraobserver agreement was considered to be good; however, the interobserver agreement was poor, with Kappa index lower than 0,2. CONCLUSION: the Fujiwara rating system showed no reproducibility to assess interspinous ligament. However, a larger disclosure and application of this rating system can turn this rating into a good instrument of comparison between an outcome of different studies.