腰椎変性すべり症における腰椎骨盤矢状面アライメントと変形性膝関節症合併の関連について

抄録

Objective: The purpose of this study was to investigate the association between sagittal lumbo-pelvic alignment and knee osteoarthritis (OA) in patients with degenerative spondylolisthesis (DS).

Methods: A total of 111 patients with DS (30 men and 81 women) with a mean age of 73±8.2 years (range: 51-93 years) who underwent corrective posterior lumbar interbody fusion (PLIF) were included in the study, and were divided into two groups: 1) the ‘OA group’ (n=31): PLIF combined with knee OA of Kellgren-Lawrence grade 2 or more, and 2) the ‘non-OA group’ (n=80): PLIF without knee OA. Preoperative lateral view radiographs of the lumbar spine in the standing position were evaluated by measuring the following factors: pelvic incidence (PI), lumbar lordosis (LL), PI-LL, sacral slope (SS), and pelvic tilt (PT).

 An unpaired students t-test was used to evaluate the differences between the OA and non-OA groups for univariate analyses. We also performed multivariate logistic regression analysis to evaluate the odds ratio for potential risk factors for the occurrence of knee OA. The threshold for significance was a P value of<0.05.

Results: PI in the OA group (57.6±6.8°) was significantly larger than in the non-OA group (50.7±8.3°) (P<0.001). LLs in the OA group (34.9±11.3°) and the non-OA group (38.8±14.7°) were not significantly different. SS in the OA group (24.6±7.8°) was significantly smaller than in the non-OA group (28.2±8.9°) (P=0.04). PT in the OA group (33.4±7.8°) was significantly larger than in the non-OA group (22.4±8.5°) (P<0.001). PI-LL in the OA group (23.2±10.5°) was significantly larger than in the non-OA group (11.9±13.5°) (P<0.001). Multivariate logistic regression analysis indicated that increases in PI, age and decrease in LL were significantly associated with knee OA (P<0.05).

Conclusions: Larger PI, PT and PI−LL values in patients with DS are thought to be associated with knee OA.